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1  //===--- Sema.h - Semantic Analysis & AST Building --------------*- C++ -*-===//
2  //
3  //                     The LLVM Compiler Infrastructure
4  //
5  // This file is distributed under the University of Illinois Open Source
6  // License. See LICENSE.TXT for details.
7  //
8  //===----------------------------------------------------------------------===//
9  //
10  // This file defines the Sema class, which performs semantic analysis and
11  // builds ASTs.
12  //
13  //===----------------------------------------------------------------------===//
14  
15  #ifndef LLVM_CLANG_SEMA_SEMA_H
16  #define LLVM_CLANG_SEMA_SEMA_H
17  
18  #include "clang/AST/Attr.h"
19  #include "clang/AST/DeclarationName.h"
20  #include "clang/AST/Expr.h"
21  #include "clang/AST/ExprObjC.h"
22  #include "clang/AST/ExternalASTSource.h"
23  #include "clang/AST/MangleNumberingContext.h"
24  #include "clang/AST/NSAPI.h"
25  #include "clang/AST/PrettyPrinter.h"
26  #include "clang/AST/TypeLoc.h"
27  #include "clang/Basic/ExpressionTraits.h"
28  #include "clang/Basic/LangOptions.h"
29  #include "clang/Basic/Module.h"
30  #include "clang/Basic/OpenMPKinds.h"
31  #include "clang/Basic/Specifiers.h"
32  #include "clang/Basic/TemplateKinds.h"
33  #include "clang/Basic/TypeTraits.h"
34  #include "clang/Sema/AnalysisBasedWarnings.h"
35  #include "clang/Sema/DeclSpec.h"
36  #include "clang/Sema/ExternalSemaSource.h"
37  #include "clang/Sema/IdentifierResolver.h"
38  #include "clang/Sema/LocInfoType.h"
39  #include "clang/Sema/ObjCMethodList.h"
40  #include "clang/Sema/Ownership.h"
41  #include "clang/Sema/Scope.h"
42  #include "clang/Sema/ScopeInfo.h"
43  #include "clang/Sema/TypoCorrection.h"
44  #include "clang/Sema/Weak.h"
45  #include "llvm/ADT/ArrayRef.h"
46  #include "llvm/ADT/Optional.h"
47  #include "llvm/ADT/SetVector.h"
48  #include "llvm/ADT/SmallPtrSet.h"
49  #include "llvm/ADT/SmallVector.h"
50  #include "llvm/ADT/TinyPtrVector.h"
51  #include <deque>
52  #include <memory>
53  #include <string>
54  #include <vector>
55  
56  namespace llvm {
57    class APSInt;
58    template <typename ValueT> struct DenseMapInfo;
59    template <typename ValueT, typename ValueInfoT> class DenseSet;
60    class SmallBitVector;
61    class InlineAsmIdentifierInfo;
62  }
63  
64  namespace clang {
65    class ADLResult;
66    class ASTConsumer;
67    class ASTContext;
68    class ASTMutationListener;
69    class ASTReader;
70    class ASTWriter;
71    class ArrayType;
72    class AttributeList;
73    class BlockDecl;
74    class CapturedDecl;
75    class CXXBasePath;
76    class CXXBasePaths;
77    class CXXBindTemporaryExpr;
78    typedef SmallVector<CXXBaseSpecifier*, 4> CXXCastPath;
79    class CXXConstructorDecl;
80    class CXXConversionDecl;
81    class CXXDeleteExpr;
82    class CXXDestructorDecl;
83    class CXXFieldCollector;
84    class CXXMemberCallExpr;
85    class CXXMethodDecl;
86    class CXXScopeSpec;
87    class CXXTemporary;
88    class CXXTryStmt;
89    class CallExpr;
90    class ClassTemplateDecl;
91    class ClassTemplatePartialSpecializationDecl;
92    class ClassTemplateSpecializationDecl;
93    class VarTemplatePartialSpecializationDecl;
94    class CodeCompleteConsumer;
95    class CodeCompletionAllocator;
96    class CodeCompletionTUInfo;
97    class CodeCompletionResult;
98    class Decl;
99    class DeclAccessPair;
100    class DeclContext;
101    class DeclRefExpr;
102    class DeclaratorDecl;
103    class DeducedTemplateArgument;
104    class DependentDiagnostic;
105    class DesignatedInitExpr;
106    class Designation;
107    class EnableIfAttr;
108    class EnumConstantDecl;
109    class Expr;
110    class ExtVectorType;
111    class ExternalSemaSource;
112    class FormatAttr;
113    class FriendDecl;
114    class FunctionDecl;
115    class FunctionProtoType;
116    class FunctionTemplateDecl;
117    class ImplicitConversionSequence;
118    class InitListExpr;
119    class InitializationKind;
120    class InitializationSequence;
121    class InitializedEntity;
122    class IntegerLiteral;
123    class LabelStmt;
124    class LambdaExpr;
125    class LangOptions;
126    class LocalInstantiationScope;
127    class LookupResult;
128    class MacroInfo;
129    typedef ArrayRef<std::pair<IdentifierInfo *, SourceLocation>> ModuleIdPath;
130    class ModuleLoader;
131    class MultiLevelTemplateArgumentList;
132    class NamedDecl;
133    class ObjCCategoryDecl;
134    class ObjCCategoryImplDecl;
135    class ObjCCompatibleAliasDecl;
136    class ObjCContainerDecl;
137    class ObjCImplDecl;
138    class ObjCImplementationDecl;
139    class ObjCInterfaceDecl;
140    class ObjCIvarDecl;
141    template <class T> class ObjCList;
142    class ObjCMessageExpr;
143    class ObjCMethodDecl;
144    class ObjCPropertyDecl;
145    class ObjCProtocolDecl;
146    class OMPThreadPrivateDecl;
147    class OMPClause;
148    struct OverloadCandidate;
149    class OverloadCandidateSet;
150    class OverloadExpr;
151    class ParenListExpr;
152    class ParmVarDecl;
153    class Preprocessor;
154    class PseudoDestructorTypeStorage;
155    class PseudoObjectExpr;
156    class QualType;
157    class StandardConversionSequence;
158    class Stmt;
159    class StringLiteral;
160    class SwitchStmt;
161    class TemplateArgument;
162    class TemplateArgumentList;
163    class TemplateArgumentLoc;
164    class TemplateDecl;
165    class TemplateParameterList;
166    class TemplatePartialOrderingContext;
167    class TemplateTemplateParmDecl;
168    class Token;
169    class TypeAliasDecl;
170    class TypedefDecl;
171    class TypedefNameDecl;
172    class TypeLoc;
173    class TypoCorrectionConsumer;
174    class UnqualifiedId;
175    class UnresolvedLookupExpr;
176    class UnresolvedMemberExpr;
177    class UnresolvedSetImpl;
178    class UnresolvedSetIterator;
179    class UsingDecl;
180    class UsingShadowDecl;
181    class ValueDecl;
182    class VarDecl;
183    class VarTemplateSpecializationDecl;
184    class VisibilityAttr;
185    class VisibleDeclConsumer;
186    class IndirectFieldDecl;
187    struct DeductionFailureInfo;
188    class TemplateSpecCandidateSet;
189  
190  namespace sema {
191    class AccessedEntity;
192    class BlockScopeInfo;
193    class CapturedRegionScopeInfo;
194    class CapturingScopeInfo;
195    class CompoundScopeInfo;
196    class DelayedDiagnostic;
197    class DelayedDiagnosticPool;
198    class FunctionScopeInfo;
199    class LambdaScopeInfo;
200    class PossiblyUnreachableDiag;
201    class TemplateDeductionInfo;
202  }
203  
204  namespace threadSafety {
205    class BeforeSet;
206    void threadSafetyCleanup(BeforeSet* Cache);
207  }
208  
209  // FIXME: No way to easily map from TemplateTypeParmTypes to
210  // TemplateTypeParmDecls, so we have this horrible PointerUnion.
211  typedef std::pair<llvm::PointerUnion<const TemplateTypeParmType*, NamedDecl*>,
212                    SourceLocation> UnexpandedParameterPack;
213  
214  /// Describes whether we've seen any nullability information for the given
215  /// file.
216  struct FileNullability {
217    /// The first pointer declarator (of any pointer kind) in the file that does
218    /// not have a corresponding nullability annotation.
219    SourceLocation PointerLoc;
220  
221    /// Which kind of pointer declarator we saw.
222    uint8_t PointerKind;
223  
224    /// Whether we saw any type nullability annotations in the given file.
225    bool SawTypeNullability = false;
226  };
227  
228  /// A mapping from file IDs to a record of whether we've seen nullability
229  /// information in that file.
230  class FileNullabilityMap {
231    /// A mapping from file IDs to the nullability information for each file ID.
232    llvm::DenseMap<FileID, FileNullability> Map;
233  
234    /// A single-element cache based on the file ID.
235    struct {
236      FileID File;
237      FileNullability Nullability;
238    } Cache;
239  
240  public:
241    FileNullability &operator[](FileID file) {
242      // Check the single-element cache.
243      if (file == Cache.File)
244        return Cache.Nullability;
245  
246      // It's not in the single-element cache; flush the cache if we have one.
247      if (!Cache.File.isInvalid()) {
248        Map[Cache.File] = Cache.Nullability;
249      }
250  
251      // Pull this entry into the cache.
252      Cache.File = file;
253      Cache.Nullability = Map[file];
254      return Cache.Nullability;
255    }
256  };
257  
258  /// Sema - This implements semantic analysis and AST building for C.
259  class Sema {
260    Sema(const Sema &) = delete;
261    void operator=(const Sema &) = delete;
262  
263    ///\brief Source of additional semantic information.
264    ExternalSemaSource *ExternalSource;
265  
266    ///\brief Whether Sema has generated a multiplexer and has to delete it.
267    bool isMultiplexExternalSource;
268  
269    static bool mightHaveNonExternalLinkage(const DeclaratorDecl *FD);
270  
271    bool isVisibleSlow(const NamedDecl *D);
272  
shouldLinkPossiblyHiddenDecl(const NamedDecl * Old,const NamedDecl * New)273    bool shouldLinkPossiblyHiddenDecl(const NamedDecl *Old,
274                                      const NamedDecl *New) {
275      // We are about to link these. It is now safe to compute the linkage of
276      // the new decl. If the new decl has external linkage, we will
277      // link it with the hidden decl (which also has external linkage) and
278      // it will keep having external linkage. If it has internal linkage, we
279      // will not link it. Since it has no previous decls, it will remain
280      // with internal linkage.
281      return isVisible(Old) || New->isExternallyVisible();
282    }
283    bool shouldLinkPossiblyHiddenDecl(LookupResult &Old, const NamedDecl *New);
284  
285  public:
286    typedef OpaquePtr<DeclGroupRef> DeclGroupPtrTy;
287    typedef OpaquePtr<TemplateName> TemplateTy;
288    typedef OpaquePtr<QualType> TypeTy;
289  
290    OpenCLOptions OpenCLFeatures;
291    FPOptions FPFeatures;
292  
293    const LangOptions &LangOpts;
294    Preprocessor &PP;
295    ASTContext &Context;
296    ASTConsumer &Consumer;
297    DiagnosticsEngine &Diags;
298    SourceManager &SourceMgr;
299  
300    /// \brief Flag indicating whether or not to collect detailed statistics.
301    bool CollectStats;
302  
303    /// \brief Code-completion consumer.
304    CodeCompleteConsumer *CodeCompleter;
305  
306    /// CurContext - This is the current declaration context of parsing.
307    DeclContext *CurContext;
308  
309    /// \brief Generally null except when we temporarily switch decl contexts,
310    /// like in \see ActOnObjCTemporaryExitContainerContext.
311    DeclContext *OriginalLexicalContext;
312  
313    /// VAListTagName - The declaration name corresponding to __va_list_tag.
314    /// This is used as part of a hack to omit that class from ADL results.
315    DeclarationName VAListTagName;
316  
317    /// PackContext - Manages the stack for \#pragma pack. An alignment
318    /// of 0 indicates default alignment.
319    void *PackContext; // Really a "PragmaPackStack*"
320  
321    bool MSStructPragmaOn; // True when \#pragma ms_struct on
322  
323    /// \brief Controls member pointer representation format under the MS ABI.
324    LangOptions::PragmaMSPointersToMembersKind
325        MSPointerToMemberRepresentationMethod;
326  
327    enum PragmaVtorDispKind {
328      PVDK_Push,          ///< #pragma vtordisp(push, mode)
329      PVDK_Set,           ///< #pragma vtordisp(mode)
330      PVDK_Pop,           ///< #pragma vtordisp(pop)
331      PVDK_Reset          ///< #pragma vtordisp()
332    };
333  
334    enum PragmaMsStackAction {
335      PSK_Reset,    // #pragma ()
336      PSK_Set,      // #pragma ("name")
337      PSK_Push,     // #pragma (push[, id])
338      PSK_Push_Set, // #pragma (push[, id], "name")
339      PSK_Pop,      // #pragma (pop[, id])
340      PSK_Pop_Set,  // #pragma (pop[, id], "name")
341    };
342  
343    /// \brief Whether to insert vtordisps prior to virtual bases in the Microsoft
344    /// C++ ABI.  Possible values are 0, 1, and 2, which mean:
345    ///
346    /// 0: Suppress all vtordisps
347    /// 1: Insert vtordisps in the presence of vbase overrides and non-trivial
348    ///    structors
349    /// 2: Always insert vtordisps to support RTTI on partially constructed
350    ///    objects
351    ///
352    /// The stack always has at least one element in it.
353    SmallVector<MSVtorDispAttr::Mode, 2> VtorDispModeStack;
354  
355    /// Stack of active SEH __finally scopes.  Can be empty.
356    SmallVector<Scope*, 2> CurrentSEHFinally;
357  
358    /// \brief Source location for newly created implicit MSInheritanceAttrs
359    SourceLocation ImplicitMSInheritanceAttrLoc;
360  
361    template<typename ValueType>
362    struct PragmaStack {
363      struct Slot {
364        llvm::StringRef StackSlotLabel;
365        ValueType Value;
366        SourceLocation PragmaLocation;
SlotPragmaStack::Slot367        Slot(llvm::StringRef StackSlotLabel,
368             ValueType Value,
369             SourceLocation PragmaLocation)
370          : StackSlotLabel(StackSlotLabel), Value(Value),
371            PragmaLocation(PragmaLocation) {}
372      };
373      void Act(SourceLocation PragmaLocation,
374               PragmaMsStackAction Action,
375               llvm::StringRef StackSlotLabel,
376               ValueType Value);
PragmaStackPragmaStack377      explicit PragmaStack(const ValueType &Value)
378        : CurrentValue(Value) {}
379      SmallVector<Slot, 2> Stack;
380      ValueType CurrentValue;
381      SourceLocation CurrentPragmaLocation;
382    };
383    // FIXME: We should serialize / deserialize these if they occur in a PCH (but
384    // we shouldn't do so if they're in a module).
385    PragmaStack<StringLiteral *> DataSegStack;
386    PragmaStack<StringLiteral *> BSSSegStack;
387    PragmaStack<StringLiteral *> ConstSegStack;
388    PragmaStack<StringLiteral *> CodeSegStack;
389  
390    /// A mapping that describes the nullability we've seen in each header file.
391    FileNullabilityMap NullabilityMap;
392  
393    /// Last section used with #pragma init_seg.
394    StringLiteral *CurInitSeg;
395    SourceLocation CurInitSegLoc;
396  
397    /// VisContext - Manages the stack for \#pragma GCC visibility.
398    void *VisContext; // Really a "PragmaVisStack*"
399  
400    /// \brief This represents the last location of a "#pragma clang optimize off"
401    /// directive if such a directive has not been closed by an "on" yet. If
402    /// optimizations are currently "on", this is set to an invalid location.
403    SourceLocation OptimizeOffPragmaLocation;
404  
405    /// \brief Flag indicating if Sema is building a recovery call expression.
406    ///
407    /// This flag is used to avoid building recovery call expressions
408    /// if Sema is already doing so, which would cause infinite recursions.
409    bool IsBuildingRecoveryCallExpr;
410  
411    /// ExprNeedsCleanups - True if the current evaluation context
412    /// requires cleanups to be run at its conclusion.
413    bool ExprNeedsCleanups;
414  
415    /// ExprCleanupObjects - This is the stack of objects requiring
416    /// cleanup that are created by the current full expression.  The
417    /// element type here is ExprWithCleanups::Object.
418    SmallVector<BlockDecl*, 8> ExprCleanupObjects;
419  
420    /// \brief Store a list of either DeclRefExprs or MemberExprs
421    ///  that contain a reference to a variable (constant) that may or may not
422    ///  be odr-used in this Expr, and we won't know until all lvalue-to-rvalue
423    ///  and discarded value conversions have been applied to all subexpressions
424    ///  of the enclosing full expression.  This is cleared at the end of each
425    ///  full expression.
426    llvm::SmallPtrSet<Expr*, 2> MaybeODRUseExprs;
427  
428    /// \brief Stack containing information about each of the nested
429    /// function, block, and method scopes that are currently active.
430    ///
431    /// This array is never empty.  Clients should ignore the first
432    /// element, which is used to cache a single FunctionScopeInfo
433    /// that's used to parse every top-level function.
434    SmallVector<sema::FunctionScopeInfo *, 4> FunctionScopes;
435  
436    typedef LazyVector<TypedefNameDecl *, ExternalSemaSource,
437                       &ExternalSemaSource::ReadExtVectorDecls, 2, 2>
438      ExtVectorDeclsType;
439  
440    /// ExtVectorDecls - This is a list all the extended vector types. This allows
441    /// us to associate a raw vector type with one of the ext_vector type names.
442    /// This is only necessary for issuing pretty diagnostics.
443    ExtVectorDeclsType ExtVectorDecls;
444  
445    /// FieldCollector - Collects CXXFieldDecls during parsing of C++ classes.
446    std::unique_ptr<CXXFieldCollector> FieldCollector;
447  
448    typedef llvm::SmallSetVector<const NamedDecl*, 16> NamedDeclSetType;
449  
450    /// \brief Set containing all declared private fields that are not used.
451    NamedDeclSetType UnusedPrivateFields;
452  
453    /// \brief Set containing all typedefs that are likely unused.
454    llvm::SmallSetVector<const TypedefNameDecl *, 4>
455        UnusedLocalTypedefNameCandidates;
456  
457    /// \brief Delete-expressions to be analyzed at the end of translation unit
458    ///
459    /// This list contains class members, and locations of delete-expressions
460    /// that could not be proven as to whether they mismatch with new-expression
461    /// used in initializer of the field.
462    typedef std::pair<SourceLocation, bool> DeleteExprLoc;
463    typedef llvm::SmallVector<DeleteExprLoc, 4> DeleteLocs;
464    llvm::MapVector<FieldDecl *, DeleteLocs> DeleteExprs;
465  
466    typedef llvm::SmallPtrSet<const CXXRecordDecl*, 8> RecordDeclSetTy;
467  
468    /// PureVirtualClassDiagSet - a set of class declarations which we have
469    /// emitted a list of pure virtual functions. Used to prevent emitting the
470    /// same list more than once.
471    std::unique_ptr<RecordDeclSetTy> PureVirtualClassDiagSet;
472  
473    /// ParsingInitForAutoVars - a set of declarations with auto types for which
474    /// we are currently parsing the initializer.
475    llvm::SmallPtrSet<const Decl*, 4> ParsingInitForAutoVars;
476  
477    /// \brief Look for a locally scoped extern "C" declaration by the given name.
478    NamedDecl *findLocallyScopedExternCDecl(DeclarationName Name);
479  
480    typedef LazyVector<VarDecl *, ExternalSemaSource,
481                       &ExternalSemaSource::ReadTentativeDefinitions, 2, 2>
482      TentativeDefinitionsType;
483  
484    /// \brief All the tentative definitions encountered in the TU.
485    TentativeDefinitionsType TentativeDefinitions;
486  
487    typedef LazyVector<const DeclaratorDecl *, ExternalSemaSource,
488                       &ExternalSemaSource::ReadUnusedFileScopedDecls, 2, 2>
489      UnusedFileScopedDeclsType;
490  
491    /// \brief The set of file scoped decls seen so far that have not been used
492    /// and must warn if not used. Only contains the first declaration.
493    UnusedFileScopedDeclsType UnusedFileScopedDecls;
494  
495    typedef LazyVector<CXXConstructorDecl *, ExternalSemaSource,
496                       &ExternalSemaSource::ReadDelegatingConstructors, 2, 2>
497      DelegatingCtorDeclsType;
498  
499    /// \brief All the delegating constructors seen so far in the file, used for
500    /// cycle detection at the end of the TU.
501    DelegatingCtorDeclsType DelegatingCtorDecls;
502  
503    /// \brief All the overriding functions seen during a class definition
504    /// that had their exception spec checks delayed, plus the overridden
505    /// function.
506    SmallVector<std::pair<const CXXMethodDecl*, const CXXMethodDecl*>, 2>
507      DelayedExceptionSpecChecks;
508  
509    /// \brief All the members seen during a class definition which were both
510    /// explicitly defaulted and had explicitly-specified exception
511    /// specifications, along with the function type containing their
512    /// user-specified exception specification. Those exception specifications
513    /// were overridden with the default specifications, but we still need to
514    /// check whether they are compatible with the default specification, and
515    /// we can't do that until the nesting set of class definitions is complete.
516    SmallVector<std::pair<CXXMethodDecl*, const FunctionProtoType*>, 2>
517      DelayedDefaultedMemberExceptionSpecs;
518  
519    typedef llvm::MapVector<const FunctionDecl *, LateParsedTemplate *>
520        LateParsedTemplateMapT;
521    LateParsedTemplateMapT LateParsedTemplateMap;
522  
523    /// \brief Callback to the parser to parse templated functions when needed.
524    typedef void LateTemplateParserCB(void *P, LateParsedTemplate &LPT);
525    typedef void LateTemplateParserCleanupCB(void *P);
526    LateTemplateParserCB *LateTemplateParser;
527    LateTemplateParserCleanupCB *LateTemplateParserCleanup;
528    void *OpaqueParser;
529  
SetLateTemplateParser(LateTemplateParserCB * LTP,LateTemplateParserCleanupCB * LTPCleanup,void * P)530    void SetLateTemplateParser(LateTemplateParserCB *LTP,
531                               LateTemplateParserCleanupCB *LTPCleanup,
532                               void *P) {
533      LateTemplateParser = LTP;
534      LateTemplateParserCleanup = LTPCleanup;
535      OpaqueParser = P;
536    }
537  
538    class DelayedDiagnostics;
539  
540    class DelayedDiagnosticsState {
541      sema::DelayedDiagnosticPool *SavedPool;
542      friend class Sema::DelayedDiagnostics;
543    };
544    typedef DelayedDiagnosticsState ParsingDeclState;
545    typedef DelayedDiagnosticsState ProcessingContextState;
546  
547    /// A class which encapsulates the logic for delaying diagnostics
548    /// during parsing and other processing.
549    class DelayedDiagnostics {
550      /// \brief The current pool of diagnostics into which delayed
551      /// diagnostics should go.
552      sema::DelayedDiagnosticPool *CurPool;
553  
554    public:
DelayedDiagnostics()555      DelayedDiagnostics() : CurPool(nullptr) {}
556  
557      /// Adds a delayed diagnostic.
558      void add(const sema::DelayedDiagnostic &diag); // in DelayedDiagnostic.h
559  
560      /// Determines whether diagnostics should be delayed.
shouldDelayDiagnostics()561      bool shouldDelayDiagnostics() { return CurPool != nullptr; }
562  
563      /// Returns the current delayed-diagnostics pool.
getCurrentPool()564      sema::DelayedDiagnosticPool *getCurrentPool() const {
565        return CurPool;
566      }
567  
568      /// Enter a new scope.  Access and deprecation diagnostics will be
569      /// collected in this pool.
push(sema::DelayedDiagnosticPool & pool)570      DelayedDiagnosticsState push(sema::DelayedDiagnosticPool &pool) {
571        DelayedDiagnosticsState state;
572        state.SavedPool = CurPool;
573        CurPool = &pool;
574        return state;
575      }
576  
577      /// Leave a delayed-diagnostic state that was previously pushed.
578      /// Do not emit any of the diagnostics.  This is performed as part
579      /// of the bookkeeping of popping a pool "properly".
popWithoutEmitting(DelayedDiagnosticsState state)580      void popWithoutEmitting(DelayedDiagnosticsState state) {
581        CurPool = state.SavedPool;
582      }
583  
584      /// Enter a new scope where access and deprecation diagnostics are
585      /// not delayed.
pushUndelayed()586      DelayedDiagnosticsState pushUndelayed() {
587        DelayedDiagnosticsState state;
588        state.SavedPool = CurPool;
589        CurPool = nullptr;
590        return state;
591      }
592  
593      /// Undo a previous pushUndelayed().
popUndelayed(DelayedDiagnosticsState state)594      void popUndelayed(DelayedDiagnosticsState state) {
595        assert(CurPool == nullptr);
596        CurPool = state.SavedPool;
597      }
598    } DelayedDiagnostics;
599  
600    /// A RAII object to temporarily push a declaration context.
601    class ContextRAII {
602    private:
603      Sema &S;
604      DeclContext *SavedContext;
605      ProcessingContextState SavedContextState;
606      QualType SavedCXXThisTypeOverride;
607  
608    public:
609      ContextRAII(Sema &S, DeclContext *ContextToPush, bool NewThisContext = true)
S(S)610        : S(S), SavedContext(S.CurContext),
611          SavedContextState(S.DelayedDiagnostics.pushUndelayed()),
612          SavedCXXThisTypeOverride(S.CXXThisTypeOverride)
613      {
614        assert(ContextToPush && "pushing null context");
615        S.CurContext = ContextToPush;
616        if (NewThisContext)
617          S.CXXThisTypeOverride = QualType();
618      }
619  
pop()620      void pop() {
621        if (!SavedContext) return;
622        S.CurContext = SavedContext;
623        S.DelayedDiagnostics.popUndelayed(SavedContextState);
624        S.CXXThisTypeOverride = SavedCXXThisTypeOverride;
625        SavedContext = nullptr;
626      }
627  
~ContextRAII()628      ~ContextRAII() {
629        pop();
630      }
631    };
632  
633    /// \brief RAII object to handle the state changes required to synthesize
634    /// a function body.
635    class SynthesizedFunctionScope {
636      Sema &S;
637      Sema::ContextRAII SavedContext;
638  
639    public:
SynthesizedFunctionScope(Sema & S,DeclContext * DC)640      SynthesizedFunctionScope(Sema &S, DeclContext *DC)
641        : S(S), SavedContext(S, DC)
642      {
643        S.PushFunctionScope();
644        S.PushExpressionEvaluationContext(Sema::PotentiallyEvaluated);
645      }
646  
~SynthesizedFunctionScope()647      ~SynthesizedFunctionScope() {
648        S.PopExpressionEvaluationContext();
649        S.PopFunctionScopeInfo();
650      }
651    };
652  
653    /// WeakUndeclaredIdentifiers - Identifiers contained in
654    /// \#pragma weak before declared. rare. may alias another
655    /// identifier, declared or undeclared
656    llvm::MapVector<IdentifierInfo *, WeakInfo> WeakUndeclaredIdentifiers;
657  
658    /// ExtnameUndeclaredIdentifiers - Identifiers contained in
659    /// \#pragma redefine_extname before declared.  Used in Solaris system headers
660    /// to define functions that occur in multiple standards to call the version
661    /// in the currently selected standard.
662    llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*> ExtnameUndeclaredIdentifiers;
663  
664  
665    /// \brief Load weak undeclared identifiers from the external source.
666    void LoadExternalWeakUndeclaredIdentifiers();
667  
668    /// WeakTopLevelDecl - Translation-unit scoped declarations generated by
669    /// \#pragma weak during processing of other Decls.
670    /// I couldn't figure out a clean way to generate these in-line, so
671    /// we store them here and handle separately -- which is a hack.
672    /// It would be best to refactor this.
673    SmallVector<Decl*,2> WeakTopLevelDecl;
674  
675    IdentifierResolver IdResolver;
676  
677    /// Translation Unit Scope - useful to Objective-C actions that need
678    /// to lookup file scope declarations in the "ordinary" C decl namespace.
679    /// For example, user-defined classes, built-in "id" type, etc.
680    Scope *TUScope;
681  
682    /// \brief The C++ "std" namespace, where the standard library resides.
683    LazyDeclPtr StdNamespace;
684  
685    /// \brief The C++ "std::bad_alloc" class, which is defined by the C++
686    /// standard library.
687    LazyDeclPtr StdBadAlloc;
688  
689    /// \brief The C++ "std::initializer_list" template, which is defined in
690    /// \<initializer_list>.
691    ClassTemplateDecl *StdInitializerList;
692  
693    /// \brief The C++ "type_info" declaration, which is defined in \<typeinfo>.
694    RecordDecl *CXXTypeInfoDecl;
695  
696    /// \brief The MSVC "_GUID" struct, which is defined in MSVC header files.
697    RecordDecl *MSVCGuidDecl;
698  
699    /// \brief Caches identifiers/selectors for NSFoundation APIs.
700    std::unique_ptr<NSAPI> NSAPIObj;
701  
702    /// \brief The declaration of the Objective-C NSNumber class.
703    ObjCInterfaceDecl *NSNumberDecl;
704  
705    /// \brief The declaration of the Objective-C NSValue class.
706    ObjCInterfaceDecl *NSValueDecl;
707  
708    /// \brief Pointer to NSNumber type (NSNumber *).
709    QualType NSNumberPointer;
710  
711    /// \brief Pointer to NSValue type (NSValue *).
712    QualType NSValuePointer;
713  
714    /// \brief The Objective-C NSNumber methods used to create NSNumber literals.
715    ObjCMethodDecl *NSNumberLiteralMethods[NSAPI::NumNSNumberLiteralMethods];
716  
717    /// \brief The declaration of the Objective-C NSString class.
718    ObjCInterfaceDecl *NSStringDecl;
719  
720    /// \brief Pointer to NSString type (NSString *).
721    QualType NSStringPointer;
722  
723    /// \brief The declaration of the stringWithUTF8String: method.
724    ObjCMethodDecl *StringWithUTF8StringMethod;
725  
726    /// \brief The declaration of the valueWithBytes:objCType: method.
727    ObjCMethodDecl *ValueWithBytesObjCTypeMethod;
728  
729    /// \brief The declaration of the Objective-C NSArray class.
730    ObjCInterfaceDecl *NSArrayDecl;
731  
732    /// \brief The declaration of the arrayWithObjects:count: method.
733    ObjCMethodDecl *ArrayWithObjectsMethod;
734  
735    /// \brief The declaration of the Objective-C NSDictionary class.
736    ObjCInterfaceDecl *NSDictionaryDecl;
737  
738    /// \brief The declaration of the dictionaryWithObjects:forKeys:count: method.
739    ObjCMethodDecl *DictionaryWithObjectsMethod;
740  
741    /// \brief id<NSCopying> type.
742    QualType QIDNSCopying;
743  
744    /// \brief will hold 'respondsToSelector:'
745    Selector RespondsToSelectorSel;
746  
747    /// \brief counter for internal MS Asm label names.
748    unsigned MSAsmLabelNameCounter;
749  
750    /// A flag to remember whether the implicit forms of operator new and delete
751    /// have been declared.
752    bool GlobalNewDeleteDeclared;
753  
754    /// A flag to indicate that we're in a context that permits abstract
755    /// references to fields.  This is really a
756    bool AllowAbstractFieldReference;
757  
758    /// \brief Describes how the expressions currently being parsed are
759    /// evaluated at run-time, if at all.
760    enum ExpressionEvaluationContext {
761      /// \brief The current expression and its subexpressions occur within an
762      /// unevaluated operand (C++11 [expr]p7), such as the subexpression of
763      /// \c sizeof, where the type of the expression may be significant but
764      /// no code will be generated to evaluate the value of the expression at
765      /// run time.
766      Unevaluated,
767  
768      /// \brief The current expression occurs within an unevaluated
769      /// operand that unconditionally permits abstract references to
770      /// fields, such as a SIZE operator in MS-style inline assembly.
771      UnevaluatedAbstract,
772  
773      /// \brief The current context is "potentially evaluated" in C++11 terms,
774      /// but the expression is evaluated at compile-time (like the values of
775      /// cases in a switch statement).
776      ConstantEvaluated,
777  
778      /// \brief The current expression is potentially evaluated at run time,
779      /// which means that code may be generated to evaluate the value of the
780      /// expression at run time.
781      PotentiallyEvaluated,
782  
783      /// \brief The current expression is potentially evaluated, but any
784      /// declarations referenced inside that expression are only used if
785      /// in fact the current expression is used.
786      ///
787      /// This value is used when parsing default function arguments, for which
788      /// we would like to provide diagnostics (e.g., passing non-POD arguments
789      /// through varargs) but do not want to mark declarations as "referenced"
790      /// until the default argument is used.
791      PotentiallyEvaluatedIfUsed
792    };
793  
794    /// \brief Data structure used to record current or nested
795    /// expression evaluation contexts.
796    struct ExpressionEvaluationContextRecord {
797      /// \brief The expression evaluation context.
798      ExpressionEvaluationContext Context;
799  
800      /// \brief Whether the enclosing context needed a cleanup.
801      bool ParentNeedsCleanups;
802  
803      /// \brief Whether we are in a decltype expression.
804      bool IsDecltype;
805  
806      /// \brief The number of active cleanup objects when we entered
807      /// this expression evaluation context.
808      unsigned NumCleanupObjects;
809  
810      /// \brief The number of typos encountered during this expression evaluation
811      /// context (i.e. the number of TypoExprs created).
812      unsigned NumTypos;
813  
814      llvm::SmallPtrSet<Expr*, 2> SavedMaybeODRUseExprs;
815  
816      /// \brief The lambdas that are present within this context, if it
817      /// is indeed an unevaluated context.
818      SmallVector<LambdaExpr *, 2> Lambdas;
819  
820      /// \brief The declaration that provides context for lambda expressions
821      /// and block literals if the normal declaration context does not
822      /// suffice, e.g., in a default function argument.
823      Decl *ManglingContextDecl;
824  
825      /// \brief The context information used to mangle lambda expressions
826      /// and block literals within this context.
827      ///
828      /// This mangling information is allocated lazily, since most contexts
829      /// do not have lambda expressions or block literals.
830      IntrusiveRefCntPtr<MangleNumberingContext> MangleNumbering;
831  
832      /// \brief If we are processing a decltype type, a set of call expressions
833      /// for which we have deferred checking the completeness of the return type.
834      SmallVector<CallExpr *, 8> DelayedDecltypeCalls;
835  
836      /// \brief If we are processing a decltype type, a set of temporary binding
837      /// expressions for which we have deferred checking the destructor.
838      SmallVector<CXXBindTemporaryExpr *, 8> DelayedDecltypeBinds;
839  
ExpressionEvaluationContextRecordExpressionEvaluationContextRecord840      ExpressionEvaluationContextRecord(ExpressionEvaluationContext Context,
841                                        unsigned NumCleanupObjects,
842                                        bool ParentNeedsCleanups,
843                                        Decl *ManglingContextDecl,
844                                        bool IsDecltype)
845        : Context(Context), ParentNeedsCleanups(ParentNeedsCleanups),
846          IsDecltype(IsDecltype), NumCleanupObjects(NumCleanupObjects),
847          NumTypos(0),
848          ManglingContextDecl(ManglingContextDecl), MangleNumbering() { }
849  
850      /// \brief Retrieve the mangling numbering context, used to consistently
851      /// number constructs like lambdas for mangling.
852      MangleNumberingContext &getMangleNumberingContext(ASTContext &Ctx);
853  
isUnevaluatedExpressionEvaluationContextRecord854      bool isUnevaluated() const {
855        return Context == Unevaluated || Context == UnevaluatedAbstract;
856      }
857    };
858  
859    /// A stack of expression evaluation contexts.
860    SmallVector<ExpressionEvaluationContextRecord, 8> ExprEvalContexts;
861  
862    /// \brief Compute the mangling number context for a lambda expression or
863    /// block literal.
864    ///
865    /// \param DC - The DeclContext containing the lambda expression or
866    /// block literal.
867    /// \param[out] ManglingContextDecl - Returns the ManglingContextDecl
868    /// associated with the context, if relevant.
869    MangleNumberingContext *getCurrentMangleNumberContext(
870      const DeclContext *DC,
871      Decl *&ManglingContextDecl);
872  
873  
874    /// SpecialMemberOverloadResult - The overloading result for a special member
875    /// function.
876    ///
877    /// This is basically a wrapper around PointerIntPair. The lowest bits of the
878    /// integer are used to determine whether overload resolution succeeded.
879    class SpecialMemberOverloadResult : public llvm::FastFoldingSetNode {
880    public:
881      enum Kind {
882        NoMemberOrDeleted,
883        Ambiguous,
884        Success
885      };
886  
887    private:
888      llvm::PointerIntPair<CXXMethodDecl*, 2> Pair;
889  
890    public:
SpecialMemberOverloadResult(const llvm::FoldingSetNodeID & ID)891      SpecialMemberOverloadResult(const llvm::FoldingSetNodeID &ID)
892        : FastFoldingSetNode(ID)
893      {}
894  
getMethod()895      CXXMethodDecl *getMethod() const { return Pair.getPointer(); }
setMethod(CXXMethodDecl * MD)896      void setMethod(CXXMethodDecl *MD) { Pair.setPointer(MD); }
897  
getKind()898      Kind getKind() const { return static_cast<Kind>(Pair.getInt()); }
setKind(Kind K)899      void setKind(Kind K) { Pair.setInt(K); }
900    };
901  
902    /// \brief A cache of special member function overload resolution results
903    /// for C++ records.
904    llvm::FoldingSet<SpecialMemberOverloadResult> SpecialMemberCache;
905  
906    /// \brief A cache of the flags available in enumerations with the flag_bits
907    /// attribute.
908    mutable llvm::DenseMap<const EnumDecl*, llvm::APInt> FlagBitsCache;
909  
910    /// \brief The kind of translation unit we are processing.
911    ///
912    /// When we're processing a complete translation unit, Sema will perform
913    /// end-of-translation-unit semantic tasks (such as creating
914    /// initializers for tentative definitions in C) once parsing has
915    /// completed. Modules and precompiled headers perform different kinds of
916    /// checks.
917    TranslationUnitKind TUKind;
918  
919    llvm::BumpPtrAllocator BumpAlloc;
920  
921    /// \brief The number of SFINAE diagnostics that have been trapped.
922    unsigned NumSFINAEErrors;
923  
924    typedef llvm::DenseMap<ParmVarDecl *, llvm::TinyPtrVector<ParmVarDecl *>>
925      UnparsedDefaultArgInstantiationsMap;
926  
927    /// \brief A mapping from parameters with unparsed default arguments to the
928    /// set of instantiations of each parameter.
929    ///
930    /// This mapping is a temporary data structure used when parsing
931    /// nested class templates or nested classes of class templates,
932    /// where we might end up instantiating an inner class before the
933    /// default arguments of its methods have been parsed.
934    UnparsedDefaultArgInstantiationsMap UnparsedDefaultArgInstantiations;
935  
936    // Contains the locations of the beginning of unparsed default
937    // argument locations.
938    llvm::DenseMap<ParmVarDecl *, SourceLocation> UnparsedDefaultArgLocs;
939  
940    /// UndefinedInternals - all the used, undefined objects which require a
941    /// definition in this translation unit.
942    llvm::DenseMap<NamedDecl *, SourceLocation> UndefinedButUsed;
943  
944    /// Obtain a sorted list of functions that are undefined but ODR-used.
945    void getUndefinedButUsed(
946        SmallVectorImpl<std::pair<NamedDecl *, SourceLocation> > &Undefined);
947  
948    /// Retrieves list of suspicious delete-expressions that will be checked at
949    /// the end of translation unit.
950    const llvm::MapVector<FieldDecl *, DeleteLocs> &
951    getMismatchingDeleteExpressions() const;
952  
953    typedef std::pair<ObjCMethodList, ObjCMethodList> GlobalMethods;
954    typedef llvm::DenseMap<Selector, GlobalMethods> GlobalMethodPool;
955  
956    /// Method Pool - allows efficient lookup when typechecking messages to "id".
957    /// We need to maintain a list, since selectors can have differing signatures
958    /// across classes. In Cocoa, this happens to be extremely uncommon (only 1%
959    /// of selectors are "overloaded").
960    /// At the head of the list it is recorded whether there were 0, 1, or >= 2
961    /// methods inside categories with a particular selector.
962    GlobalMethodPool MethodPool;
963  
964    /// Method selectors used in a \@selector expression. Used for implementation
965    /// of -Wselector.
966    llvm::MapVector<Selector, SourceLocation> ReferencedSelectors;
967  
968    /// Kinds of C++ special members.
969    enum CXXSpecialMember {
970      CXXDefaultConstructor,
971      CXXCopyConstructor,
972      CXXMoveConstructor,
973      CXXCopyAssignment,
974      CXXMoveAssignment,
975      CXXDestructor,
976      CXXInvalid
977    };
978  
979    typedef std::pair<CXXRecordDecl*, CXXSpecialMember> SpecialMemberDecl;
980  
981    /// The C++ special members which we are currently in the process of
982    /// declaring. If this process recursively triggers the declaration of the
983    /// same special member, we should act as if it is not yet declared.
984    llvm::SmallSet<SpecialMemberDecl, 4> SpecialMembersBeingDeclared;
985  
986    void ReadMethodPool(Selector Sel);
987  
988    /// Private Helper predicate to check for 'self'.
989    bool isSelfExpr(Expr *RExpr);
990    bool isSelfExpr(Expr *RExpr, const ObjCMethodDecl *Method);
991  
992    /// \brief Cause the active diagnostic on the DiagosticsEngine to be
993    /// emitted. This is closely coupled to the SemaDiagnosticBuilder class and
994    /// should not be used elsewhere.
995    void EmitCurrentDiagnostic(unsigned DiagID);
996  
997    /// Records and restores the FP_CONTRACT state on entry/exit of compound
998    /// statements.
999    class FPContractStateRAII {
1000    public:
FPContractStateRAII(Sema & S)1001      FPContractStateRAII(Sema& S)
1002        : S(S), OldFPContractState(S.FPFeatures.fp_contract) {}
~FPContractStateRAII()1003      ~FPContractStateRAII() {
1004        S.FPFeatures.fp_contract = OldFPContractState;
1005      }
1006    private:
1007      Sema& S;
1008      bool OldFPContractState : 1;
1009    };
1010  
1011    /// Records and restores the vtordisp state on entry/exit of C++ method body.
1012    class VtorDispStackRAII {
1013    public:
VtorDispStackRAII(Sema & S,bool ShouldSaveAndRestore)1014      VtorDispStackRAII(Sema &S, bool ShouldSaveAndRestore)
1015        : S(S), ShouldSaveAndRestore(ShouldSaveAndRestore), OldVtorDispStack() {
1016        if (ShouldSaveAndRestore)
1017          OldVtorDispStack = S.VtorDispModeStack;
1018      }
~VtorDispStackRAII()1019      ~VtorDispStackRAII() {
1020        if (ShouldSaveAndRestore)
1021          S.VtorDispModeStack = OldVtorDispStack;
1022      }
1023    private:
1024      Sema &S;
1025      bool ShouldSaveAndRestore;
1026      SmallVector<MSVtorDispAttr::Mode, 2> OldVtorDispStack;
1027    };
1028  
1029    void addImplicitTypedef(StringRef Name, QualType T);
1030  
1031  public:
1032    Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
1033         TranslationUnitKind TUKind = TU_Complete,
1034         CodeCompleteConsumer *CompletionConsumer = nullptr);
1035    ~Sema();
1036  
1037    /// \brief Perform initialization that occurs after the parser has been
1038    /// initialized but before it parses anything.
1039    void Initialize();
1040  
getLangOpts()1041    const LangOptions &getLangOpts() const { return LangOpts; }
getOpenCLOptions()1042    OpenCLOptions &getOpenCLOptions() { return OpenCLFeatures; }
getFPOptions()1043    FPOptions     &getFPOptions() { return FPFeatures; }
1044  
getDiagnostics()1045    DiagnosticsEngine &getDiagnostics() const { return Diags; }
getSourceManager()1046    SourceManager &getSourceManager() const { return SourceMgr; }
getPreprocessor()1047    Preprocessor &getPreprocessor() const { return PP; }
getASTContext()1048    ASTContext &getASTContext() const { return Context; }
getASTConsumer()1049    ASTConsumer &getASTConsumer() const { return Consumer; }
1050    ASTMutationListener *getASTMutationListener() const;
getExternalSource()1051    ExternalSemaSource* getExternalSource() const { return ExternalSource; }
1052  
1053    ///\brief Registers an external source. If an external source already exists,
1054    /// creates a multiplex external source and appends to it.
1055    ///
1056    ///\param[in] E - A non-null external sema source.
1057    ///
1058    void addExternalSource(ExternalSemaSource *E);
1059  
1060    void PrintStats() const;
1061  
1062    /// \brief Helper class that creates diagnostics with optional
1063    /// template instantiation stacks.
1064    ///
1065    /// This class provides a wrapper around the basic DiagnosticBuilder
1066    /// class that emits diagnostics. SemaDiagnosticBuilder is
1067    /// responsible for emitting the diagnostic (as DiagnosticBuilder
1068    /// does) and, if the diagnostic comes from inside a template
1069    /// instantiation, printing the template instantiation stack as
1070    /// well.
1071    class SemaDiagnosticBuilder : public DiagnosticBuilder {
1072      Sema &SemaRef;
1073      unsigned DiagID;
1074  
1075    public:
SemaDiagnosticBuilder(DiagnosticBuilder & DB,Sema & SemaRef,unsigned DiagID)1076      SemaDiagnosticBuilder(DiagnosticBuilder &DB, Sema &SemaRef, unsigned DiagID)
1077        : DiagnosticBuilder(DB), SemaRef(SemaRef), DiagID(DiagID) { }
1078  
1079      // This is a cunning lie. DiagnosticBuilder actually performs move
1080      // construction in its copy constructor (but due to varied uses, it's not
1081      // possible to conveniently express this as actual move construction). So
1082      // the default copy ctor here is fine, because the base class disables the
1083      // source anyway, so the user-defined ~SemaDiagnosticBuilder is a safe no-op
1084      // in that case anwyay.
1085      SemaDiagnosticBuilder(const SemaDiagnosticBuilder&) = default;
1086  
~SemaDiagnosticBuilder()1087      ~SemaDiagnosticBuilder() {
1088        // If we aren't active, there is nothing to do.
1089        if (!isActive()) return;
1090  
1091        // Otherwise, we need to emit the diagnostic. First flush the underlying
1092        // DiagnosticBuilder data, and clear the diagnostic builder itself so it
1093        // won't emit the diagnostic in its own destructor.
1094        //
1095        // This seems wasteful, in that as written the DiagnosticBuilder dtor will
1096        // do its own needless checks to see if the diagnostic needs to be
1097        // emitted. However, because we take care to ensure that the builder
1098        // objects never escape, a sufficiently smart compiler will be able to
1099        // eliminate that code.
1100        FlushCounts();
1101        Clear();
1102  
1103        // Dispatch to Sema to emit the diagnostic.
1104        SemaRef.EmitCurrentDiagnostic(DiagID);
1105      }
1106  
1107      /// Teach operator<< to produce an object of the correct type.
1108      template<typename T>
1109      friend const SemaDiagnosticBuilder &operator<<(
1110          const SemaDiagnosticBuilder &Diag, const T &Value) {
1111        const DiagnosticBuilder &BaseDiag = Diag;
1112        BaseDiag << Value;
1113        return Diag;
1114      }
1115    };
1116  
1117    /// \brief Emit a diagnostic.
Diag(SourceLocation Loc,unsigned DiagID)1118    SemaDiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID) {
1119      DiagnosticBuilder DB = Diags.Report(Loc, DiagID);
1120      return SemaDiagnosticBuilder(DB, *this, DiagID);
1121    }
1122  
1123    /// \brief Emit a partial diagnostic.
1124    SemaDiagnosticBuilder Diag(SourceLocation Loc, const PartialDiagnostic& PD);
1125  
1126    /// \brief Build a partial diagnostic.
1127    PartialDiagnostic PDiag(unsigned DiagID = 0); // in SemaInternal.h
1128  
1129    bool findMacroSpelling(SourceLocation &loc, StringRef name);
1130  
1131    /// \brief Get a string to suggest for zero-initialization of a type.
1132    std::string
1133    getFixItZeroInitializerForType(QualType T, SourceLocation Loc) const;
1134    std::string getFixItZeroLiteralForType(QualType T, SourceLocation Loc) const;
1135  
1136    /// \brief Calls \c Lexer::getLocForEndOfToken()
1137    SourceLocation getLocForEndOfToken(SourceLocation Loc, unsigned Offset = 0);
1138  
1139    /// \brief Retrieve the module loader associated with the preprocessor.
1140    ModuleLoader &getModuleLoader() const;
1141  
1142    void emitAndClearUnusedLocalTypedefWarnings();
1143  
1144    void ActOnEndOfTranslationUnit();
1145  
1146    void CheckDelegatingCtorCycles();
1147  
1148    Scope *getScopeForContext(DeclContext *Ctx);
1149  
1150    void PushFunctionScope();
1151    void PushBlockScope(Scope *BlockScope, BlockDecl *Block);
1152    sema::LambdaScopeInfo *PushLambdaScope();
1153  
1154    /// \brief This is used to inform Sema what the current TemplateParameterDepth
1155    /// is during Parsing.  Currently it is used to pass on the depth
1156    /// when parsing generic lambda 'auto' parameters.
1157    void RecordParsingTemplateParameterDepth(unsigned Depth);
1158  
1159    void PushCapturedRegionScope(Scope *RegionScope, CapturedDecl *CD,
1160                                 RecordDecl *RD,
1161                                 CapturedRegionKind K);
1162    void
1163    PopFunctionScopeInfo(const sema::AnalysisBasedWarnings::Policy *WP = nullptr,
1164                         const Decl *D = nullptr,
1165                         const BlockExpr *blkExpr = nullptr);
1166  
getCurFunction()1167    sema::FunctionScopeInfo *getCurFunction() const {
1168      return FunctionScopes.back();
1169    }
1170  
getEnclosingFunction()1171    sema::FunctionScopeInfo *getEnclosingFunction() const {
1172      if (FunctionScopes.empty())
1173        return nullptr;
1174  
1175      for (int e = FunctionScopes.size()-1; e >= 0; --e) {
1176        if (isa<sema::BlockScopeInfo>(FunctionScopes[e]))
1177          continue;
1178        return FunctionScopes[e];
1179      }
1180      return nullptr;
1181    }
1182  
1183    template <typename ExprT>
1184    void recordUseOfEvaluatedWeak(const ExprT *E, bool IsRead=true) {
1185      if (!isUnevaluatedContext())
1186        getCurFunction()->recordUseOfWeak(E, IsRead);
1187    }
1188  
1189    void PushCompoundScope();
1190    void PopCompoundScope();
1191  
1192    sema::CompoundScopeInfo &getCurCompoundScope() const;
1193  
1194    bool hasAnyUnrecoverableErrorsInThisFunction() const;
1195  
1196    /// \brief Retrieve the current block, if any.
1197    sema::BlockScopeInfo *getCurBlock();
1198  
1199    /// \brief Retrieve the current lambda scope info, if any.
1200    sema::LambdaScopeInfo *getCurLambda();
1201  
1202    /// \brief Retrieve the current generic lambda info, if any.
1203    sema::LambdaScopeInfo *getCurGenericLambda();
1204  
1205    /// \brief Retrieve the current captured region, if any.
1206    sema::CapturedRegionScopeInfo *getCurCapturedRegion();
1207  
1208    /// WeakTopLevelDeclDecls - access to \#pragma weak-generated Decls
WeakTopLevelDecls()1209    SmallVectorImpl<Decl *> &WeakTopLevelDecls() { return WeakTopLevelDecl; }
1210  
1211    void ActOnComment(SourceRange Comment);
1212  
1213    //===--------------------------------------------------------------------===//
1214    // Type Analysis / Processing: SemaType.cpp.
1215    //
1216  
1217    QualType BuildQualifiedType(QualType T, SourceLocation Loc, Qualifiers Qs,
1218                                const DeclSpec *DS = nullptr);
1219    QualType BuildQualifiedType(QualType T, SourceLocation Loc, unsigned CVRA,
1220                                const DeclSpec *DS = nullptr);
1221    QualType BuildPointerType(QualType T,
1222                              SourceLocation Loc, DeclarationName Entity);
1223    QualType BuildReferenceType(QualType T, bool LValueRef,
1224                                SourceLocation Loc, DeclarationName Entity);
1225    QualType BuildArrayType(QualType T, ArrayType::ArraySizeModifier ASM,
1226                            Expr *ArraySize, unsigned Quals,
1227                            SourceRange Brackets, DeclarationName Entity);
1228    QualType BuildExtVectorType(QualType T, Expr *ArraySize,
1229                                SourceLocation AttrLoc);
1230  
1231    bool CheckFunctionReturnType(QualType T, SourceLocation Loc);
1232  
1233    /// \brief Build a function type.
1234    ///
1235    /// This routine checks the function type according to C++ rules and
1236    /// under the assumption that the result type and parameter types have
1237    /// just been instantiated from a template. It therefore duplicates
1238    /// some of the behavior of GetTypeForDeclarator, but in a much
1239    /// simpler form that is only suitable for this narrow use case.
1240    ///
1241    /// \param T The return type of the function.
1242    ///
1243    /// \param ParamTypes The parameter types of the function. This array
1244    /// will be modified to account for adjustments to the types of the
1245    /// function parameters.
1246    ///
1247    /// \param Loc The location of the entity whose type involves this
1248    /// function type or, if there is no such entity, the location of the
1249    /// type that will have function type.
1250    ///
1251    /// \param Entity The name of the entity that involves the function
1252    /// type, if known.
1253    ///
1254    /// \param EPI Extra information about the function type. Usually this will
1255    /// be taken from an existing function with the same prototype.
1256    ///
1257    /// \returns A suitable function type, if there are no errors. The
1258    /// unqualified type will always be a FunctionProtoType.
1259    /// Otherwise, returns a NULL type.
1260    QualType BuildFunctionType(QualType T,
1261                               MutableArrayRef<QualType> ParamTypes,
1262                               SourceLocation Loc, DeclarationName Entity,
1263                               const FunctionProtoType::ExtProtoInfo &EPI);
1264  
1265    QualType BuildMemberPointerType(QualType T, QualType Class,
1266                                    SourceLocation Loc,
1267                                    DeclarationName Entity);
1268    QualType BuildBlockPointerType(QualType T,
1269                                   SourceLocation Loc, DeclarationName Entity);
1270    QualType BuildParenType(QualType T);
1271    QualType BuildAtomicType(QualType T, SourceLocation Loc);
1272  
1273    TypeSourceInfo *GetTypeForDeclarator(Declarator &D, Scope *S);
1274    TypeSourceInfo *GetTypeForDeclaratorCast(Declarator &D, QualType FromTy);
1275    TypeSourceInfo *GetTypeSourceInfoForDeclarator(Declarator &D, QualType T,
1276                                                 TypeSourceInfo *ReturnTypeInfo);
1277  
1278    /// \brief Package the given type and TSI into a ParsedType.
1279    ParsedType CreateParsedType(QualType T, TypeSourceInfo *TInfo);
1280    DeclarationNameInfo GetNameForDeclarator(Declarator &D);
1281    DeclarationNameInfo GetNameFromUnqualifiedId(const UnqualifiedId &Name);
1282    static QualType GetTypeFromParser(ParsedType Ty,
1283                                      TypeSourceInfo **TInfo = nullptr);
1284    CanThrowResult canThrow(const Expr *E);
1285    const FunctionProtoType *ResolveExceptionSpec(SourceLocation Loc,
1286                                                  const FunctionProtoType *FPT);
1287    void UpdateExceptionSpec(FunctionDecl *FD,
1288                             const FunctionProtoType::ExceptionSpecInfo &ESI);
1289    bool CheckSpecifiedExceptionType(QualType &T, SourceRange Range);
1290    bool CheckDistantExceptionSpec(QualType T);
1291    bool CheckEquivalentExceptionSpec(FunctionDecl *Old, FunctionDecl *New);
1292    bool CheckEquivalentExceptionSpec(
1293        const FunctionProtoType *Old, SourceLocation OldLoc,
1294        const FunctionProtoType *New, SourceLocation NewLoc);
1295    bool CheckEquivalentExceptionSpec(
1296        const PartialDiagnostic &DiagID, const PartialDiagnostic & NoteID,
1297        const FunctionProtoType *Old, SourceLocation OldLoc,
1298        const FunctionProtoType *New, SourceLocation NewLoc,
1299        bool *MissingExceptionSpecification = nullptr,
1300        bool *MissingEmptyExceptionSpecification = nullptr,
1301        bool AllowNoexceptAllMatchWithNoSpec = false,
1302        bool IsOperatorNew = false);
1303    bool CheckExceptionSpecSubset(
1304        const PartialDiagnostic &DiagID, const PartialDiagnostic & NoteID,
1305        const FunctionProtoType *Superset, SourceLocation SuperLoc,
1306        const FunctionProtoType *Subset, SourceLocation SubLoc);
1307    bool CheckParamExceptionSpec(const PartialDiagnostic & NoteID,
1308        const FunctionProtoType *Target, SourceLocation TargetLoc,
1309        const FunctionProtoType *Source, SourceLocation SourceLoc);
1310  
1311    TypeResult ActOnTypeName(Scope *S, Declarator &D);
1312  
1313    /// \brief The parser has parsed the context-sensitive type 'instancetype'
1314    /// in an Objective-C message declaration. Return the appropriate type.
1315    ParsedType ActOnObjCInstanceType(SourceLocation Loc);
1316  
1317    /// \brief Abstract class used to diagnose incomplete types.
1318    struct TypeDiagnoser {
TypeDiagnoserTypeDiagnoser1319      TypeDiagnoser() {}
1320  
1321      virtual void diagnose(Sema &S, SourceLocation Loc, QualType T) = 0;
~TypeDiagnoserTypeDiagnoser1322      virtual ~TypeDiagnoser() {}
1323    };
1324  
getPrintable(int I)1325    static int getPrintable(int I) { return I; }
getPrintable(unsigned I)1326    static unsigned getPrintable(unsigned I) { return I; }
getPrintable(bool B)1327    static bool getPrintable(bool B) { return B; }
getPrintable(const char * S)1328    static const char * getPrintable(const char *S) { return S; }
getPrintable(StringRef S)1329    static StringRef getPrintable(StringRef S) { return S; }
getPrintable(const std::string & S)1330    static const std::string &getPrintable(const std::string &S) { return S; }
getPrintable(const IdentifierInfo * II)1331    static const IdentifierInfo *getPrintable(const IdentifierInfo *II) {
1332      return II;
1333    }
getPrintable(DeclarationName N)1334    static DeclarationName getPrintable(DeclarationName N) { return N; }
getPrintable(QualType T)1335    static QualType getPrintable(QualType T) { return T; }
getPrintable(SourceRange R)1336    static SourceRange getPrintable(SourceRange R) { return R; }
getPrintable(SourceLocation L)1337    static SourceRange getPrintable(SourceLocation L) { return L; }
getPrintable(const Expr * E)1338    static SourceRange getPrintable(const Expr *E) { return E->getSourceRange(); }
getPrintable(TypeLoc TL)1339    static SourceRange getPrintable(TypeLoc TL) { return TL.getSourceRange();}
1340  
1341    template <typename... Ts> class BoundTypeDiagnoser : public TypeDiagnoser {
1342      unsigned DiagID;
1343      std::tuple<const Ts &...> Args;
1344  
1345      template <std::size_t... Is>
emit(const SemaDiagnosticBuilder & DB,llvm::index_sequence<Is...>)1346      void emit(const SemaDiagnosticBuilder &DB,
1347                llvm::index_sequence<Is...>) const {
1348        // Apply all tuple elements to the builder in order.
1349        bool Dummy[] = {false, (DB << getPrintable(std::get<Is>(Args)))...};
1350        (void)Dummy;
1351      }
1352  
1353    public:
BoundTypeDiagnoser(unsigned DiagID,const Ts &...Args)1354      BoundTypeDiagnoser(unsigned DiagID, const Ts &...Args)
1355          : TypeDiagnoser(), DiagID(DiagID), Args(Args...) {
1356        assert(DiagID != 0 && "no diagnostic for type diagnoser");
1357      }
1358  
diagnose(Sema & S,SourceLocation Loc,QualType T)1359      void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
1360        const SemaDiagnosticBuilder &DB = S.Diag(Loc, DiagID);
1361        emit(DB, llvm::index_sequence_for<Ts...>());
1362        DB << T;
1363      }
1364    };
1365  
1366  private:
1367    bool RequireCompleteTypeImpl(SourceLocation Loc, QualType T,
1368                                 TypeDiagnoser *Diagnoser);
1369  
1370    VisibleModuleSet VisibleModules;
1371    llvm::SmallVector<VisibleModuleSet, 16> VisibleModulesStack;
1372  
1373    Module *CachedFakeTopLevelModule;
1374  
1375  public:
1376    /// \brief Get the module owning an entity.
1377    Module *getOwningModule(Decl *Entity);
1378  
1379    /// \brief Make a merged definition of an existing hidden definition \p ND
1380    /// visible at the specified location.
1381    void makeMergedDefinitionVisible(NamedDecl *ND, SourceLocation Loc);
1382  
isModuleVisible(Module * M)1383    bool isModuleVisible(Module *M) { return VisibleModules.isVisible(M); }
1384  
1385    /// Determine whether a declaration is visible to name lookup.
isVisible(const NamedDecl * D)1386    bool isVisible(const NamedDecl *D) {
1387      return !D->isHidden() || isVisibleSlow(D);
1388    }
1389    bool hasVisibleMergedDefinition(NamedDecl *Def);
1390  
1391    /// Determine if \p D has a visible definition. If not, suggest a declaration
1392    /// that should be made visible to expose the definition.
1393    bool hasVisibleDefinition(NamedDecl *D, NamedDecl **Suggested,
1394                              bool OnlyNeedComplete = false);
hasVisibleDefinition(const NamedDecl * D)1395    bool hasVisibleDefinition(const NamedDecl *D) {
1396      NamedDecl *Hidden;
1397      return hasVisibleDefinition(const_cast<NamedDecl*>(D), &Hidden);
1398    }
1399  
1400    /// Determine if the template parameter \p D has a visible default argument.
1401    bool
1402    hasVisibleDefaultArgument(const NamedDecl *D,
1403                              llvm::SmallVectorImpl<Module *> *Modules = nullptr);
1404  
1405    /// Determine if \p A and \p B are equivalent internal linkage declarations
1406    /// from different modules, and thus an ambiguity error can be downgraded to
1407    /// an extension warning.
1408    bool isEquivalentInternalLinkageDeclaration(const NamedDecl *A,
1409                                                const NamedDecl *B);
1410    void diagnoseEquivalentInternalLinkageDeclarations(
1411        SourceLocation Loc, const NamedDecl *D,
1412        ArrayRef<const NamedDecl *> Equiv);
1413  
isCompleteType(SourceLocation Loc,QualType T)1414    bool isCompleteType(SourceLocation Loc, QualType T) {
1415      return !RequireCompleteTypeImpl(Loc, T, nullptr);
1416    }
1417    bool RequireCompleteType(SourceLocation Loc, QualType T,
1418                             TypeDiagnoser &Diagnoser);
1419    bool RequireCompleteType(SourceLocation Loc, QualType T,
1420                             unsigned DiagID);
1421  
1422    template <typename... Ts>
RequireCompleteType(SourceLocation Loc,QualType T,unsigned DiagID,const Ts &...Args)1423    bool RequireCompleteType(SourceLocation Loc, QualType T, unsigned DiagID,
1424                             const Ts &...Args) {
1425      BoundTypeDiagnoser<Ts...> Diagnoser(DiagID, Args...);
1426      return RequireCompleteType(Loc, T, Diagnoser);
1427    }
1428  
1429    void completeExprArrayBound(Expr *E);
1430    bool RequireCompleteExprType(Expr *E, TypeDiagnoser &Diagnoser);
1431    bool RequireCompleteExprType(Expr *E, unsigned DiagID);
1432  
1433    template <typename... Ts>
RequireCompleteExprType(Expr * E,unsigned DiagID,const Ts &...Args)1434    bool RequireCompleteExprType(Expr *E, unsigned DiagID, const Ts &...Args) {
1435      BoundTypeDiagnoser<Ts...> Diagnoser(DiagID, Args...);
1436      return RequireCompleteExprType(E, Diagnoser);
1437    }
1438  
1439    bool RequireLiteralType(SourceLocation Loc, QualType T,
1440                            TypeDiagnoser &Diagnoser);
1441    bool RequireLiteralType(SourceLocation Loc, QualType T, unsigned DiagID);
1442  
1443    template <typename... Ts>
RequireLiteralType(SourceLocation Loc,QualType T,unsigned DiagID,const Ts &...Args)1444    bool RequireLiteralType(SourceLocation Loc, QualType T, unsigned DiagID,
1445                            const Ts &...Args) {
1446      BoundTypeDiagnoser<Ts...> Diagnoser(DiagID, Args...);
1447      return RequireLiteralType(Loc, T, Diagnoser);
1448    }
1449  
1450    QualType getElaboratedType(ElaboratedTypeKeyword Keyword,
1451                               const CXXScopeSpec &SS, QualType T);
1452  
1453    QualType BuildTypeofExprType(Expr *E, SourceLocation Loc);
1454    /// If AsUnevaluated is false, E is treated as though it were an evaluated
1455    /// context, such as when building a type for decltype(auto).
1456    QualType BuildDecltypeType(Expr *E, SourceLocation Loc,
1457                               bool AsUnevaluated = true);
1458    QualType BuildUnaryTransformType(QualType BaseType,
1459                                     UnaryTransformType::UTTKind UKind,
1460                                     SourceLocation Loc);
1461  
1462    //===--------------------------------------------------------------------===//
1463    // Symbol table / Decl tracking callbacks: SemaDecl.cpp.
1464    //
1465  
1466    struct SkipBodyInfo {
SkipBodyInfoSkipBodyInfo1467      SkipBodyInfo() : ShouldSkip(false), Previous(nullptr) {}
1468      bool ShouldSkip;
1469      NamedDecl *Previous;
1470    };
1471  
1472    /// List of decls defined in a function prototype. This contains EnumConstants
1473    /// that incorrectly end up in translation unit scope because there is no
1474    /// function to pin them on. ActOnFunctionDeclarator reads this list and patches
1475    /// them into the FunctionDecl.
1476    std::vector<NamedDecl*> DeclsInPrototypeScope;
1477  
1478    DeclGroupPtrTy ConvertDeclToDeclGroup(Decl *Ptr, Decl *OwnedType = nullptr);
1479  
1480    void DiagnoseUseOfUnimplementedSelectors();
1481  
1482    bool isSimpleTypeSpecifier(tok::TokenKind Kind) const;
1483  
1484    ParsedType getTypeName(const IdentifierInfo &II, SourceLocation NameLoc,
1485                           Scope *S, CXXScopeSpec *SS = nullptr,
1486                           bool isClassName = false,
1487                           bool HasTrailingDot = false,
1488                           ParsedType ObjectType = ParsedType(),
1489                           bool IsCtorOrDtorName = false,
1490                           bool WantNontrivialTypeSourceInfo = false,
1491                           IdentifierInfo **CorrectedII = nullptr);
1492    TypeSpecifierType isTagName(IdentifierInfo &II, Scope *S);
1493    bool isMicrosoftMissingTypename(const CXXScopeSpec *SS, Scope *S);
1494    void DiagnoseUnknownTypeName(IdentifierInfo *&II,
1495                                 SourceLocation IILoc,
1496                                 Scope *S,
1497                                 CXXScopeSpec *SS,
1498                                 ParsedType &SuggestedType,
1499                                 bool AllowClassTemplates = false);
1500  
1501    /// \brief For compatibility with MSVC, we delay parsing of some default
1502    /// template type arguments until instantiation time.  Emits a warning and
1503    /// returns a synthesized DependentNameType that isn't really dependent on any
1504    /// other template arguments.
1505    ParsedType ActOnDelayedDefaultTemplateArg(const IdentifierInfo &II,
1506                                              SourceLocation NameLoc);
1507  
1508    /// \brief Describes the result of the name lookup and resolution performed
1509    /// by \c ClassifyName().
1510    enum NameClassificationKind {
1511      NC_Unknown,
1512      NC_Error,
1513      NC_Keyword,
1514      NC_Type,
1515      NC_Expression,
1516      NC_NestedNameSpecifier,
1517      NC_TypeTemplate,
1518      NC_VarTemplate,
1519      NC_FunctionTemplate
1520    };
1521  
1522    class NameClassification {
1523      NameClassificationKind Kind;
1524      ExprResult Expr;
1525      TemplateName Template;
1526      ParsedType Type;
1527      const IdentifierInfo *Keyword;
1528  
NameClassification(NameClassificationKind Kind)1529      explicit NameClassification(NameClassificationKind Kind) : Kind(Kind) {}
1530  
1531    public:
NameClassification(ExprResult Expr)1532      NameClassification(ExprResult Expr) : Kind(NC_Expression), Expr(Expr) {}
1533  
NameClassification(ParsedType Type)1534      NameClassification(ParsedType Type) : Kind(NC_Type), Type(Type) {}
1535  
NameClassification(const IdentifierInfo * Keyword)1536      NameClassification(const IdentifierInfo *Keyword)
1537        : Kind(NC_Keyword), Keyword(Keyword) { }
1538  
Error()1539      static NameClassification Error() {
1540        return NameClassification(NC_Error);
1541      }
1542  
Unknown()1543      static NameClassification Unknown() {
1544        return NameClassification(NC_Unknown);
1545      }
1546  
NestedNameSpecifier()1547      static NameClassification NestedNameSpecifier() {
1548        return NameClassification(NC_NestedNameSpecifier);
1549      }
1550  
TypeTemplate(TemplateName Name)1551      static NameClassification TypeTemplate(TemplateName Name) {
1552        NameClassification Result(NC_TypeTemplate);
1553        Result.Template = Name;
1554        return Result;
1555      }
1556  
VarTemplate(TemplateName Name)1557      static NameClassification VarTemplate(TemplateName Name) {
1558        NameClassification Result(NC_VarTemplate);
1559        Result.Template = Name;
1560        return Result;
1561      }
1562  
FunctionTemplate(TemplateName Name)1563      static NameClassification FunctionTemplate(TemplateName Name) {
1564        NameClassification Result(NC_FunctionTemplate);
1565        Result.Template = Name;
1566        return Result;
1567      }
1568  
getKind()1569      NameClassificationKind getKind() const { return Kind; }
1570  
getType()1571      ParsedType getType() const {
1572        assert(Kind == NC_Type);
1573        return Type;
1574      }
1575  
getExpression()1576      ExprResult getExpression() const {
1577        assert(Kind == NC_Expression);
1578        return Expr;
1579      }
1580  
getTemplateName()1581      TemplateName getTemplateName() const {
1582        assert(Kind == NC_TypeTemplate || Kind == NC_FunctionTemplate ||
1583               Kind == NC_VarTemplate);
1584        return Template;
1585      }
1586  
getTemplateNameKind()1587      TemplateNameKind getTemplateNameKind() const {
1588        switch (Kind) {
1589        case NC_TypeTemplate:
1590          return TNK_Type_template;
1591        case NC_FunctionTemplate:
1592          return TNK_Function_template;
1593        case NC_VarTemplate:
1594          return TNK_Var_template;
1595        default:
1596          llvm_unreachable("unsupported name classification.");
1597        }
1598      }
1599    };
1600  
1601    /// \brief Perform name lookup on the given name, classifying it based on
1602    /// the results of name lookup and the following token.
1603    ///
1604    /// This routine is used by the parser to resolve identifiers and help direct
1605    /// parsing. When the identifier cannot be found, this routine will attempt
1606    /// to correct the typo and classify based on the resulting name.
1607    ///
1608    /// \param S The scope in which we're performing name lookup.
1609    ///
1610    /// \param SS The nested-name-specifier that precedes the name.
1611    ///
1612    /// \param Name The identifier. If typo correction finds an alternative name,
1613    /// this pointer parameter will be updated accordingly.
1614    ///
1615    /// \param NameLoc The location of the identifier.
1616    ///
1617    /// \param NextToken The token following the identifier. Used to help
1618    /// disambiguate the name.
1619    ///
1620    /// \param IsAddressOfOperand True if this name is the operand of a unary
1621    ///        address of ('&') expression, assuming it is classified as an
1622    ///        expression.
1623    ///
1624    /// \param CCC The correction callback, if typo correction is desired.
1625    NameClassification
1626    ClassifyName(Scope *S, CXXScopeSpec &SS, IdentifierInfo *&Name,
1627                 SourceLocation NameLoc, const Token &NextToken,
1628                 bool IsAddressOfOperand,
1629                 std::unique_ptr<CorrectionCandidateCallback> CCC = nullptr);
1630  
1631    Decl *ActOnDeclarator(Scope *S, Declarator &D);
1632  
1633    NamedDecl *HandleDeclarator(Scope *S, Declarator &D,
1634                                MultiTemplateParamsArg TemplateParameterLists);
1635    void RegisterLocallyScopedExternCDecl(NamedDecl *ND, Scope *S);
1636    bool DiagnoseClassNameShadow(DeclContext *DC, DeclarationNameInfo Info);
1637    bool diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC,
1638                                      DeclarationName Name,
1639                                      SourceLocation Loc);
1640    void
1641    diagnoseIgnoredQualifiers(unsigned DiagID, unsigned Quals,
1642                              SourceLocation FallbackLoc,
1643                              SourceLocation ConstQualLoc = SourceLocation(),
1644                              SourceLocation VolatileQualLoc = SourceLocation(),
1645                              SourceLocation RestrictQualLoc = SourceLocation(),
1646                              SourceLocation AtomicQualLoc = SourceLocation());
1647  
1648    static bool adjustContextForLocalExternDecl(DeclContext *&DC);
1649    void DiagnoseFunctionSpecifiers(const DeclSpec &DS);
1650    void CheckShadow(Scope *S, VarDecl *D, const LookupResult& R);
1651    void CheckShadow(Scope *S, VarDecl *D);
1652    void CheckCastAlign(Expr *Op, QualType T, SourceRange TRange);
1653    void handleTagNumbering(const TagDecl *Tag, Scope *TagScope);
1654    void setTagNameForLinkagePurposes(TagDecl *TagFromDeclSpec,
1655                                      TypedefNameDecl *NewTD);
1656    void CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *D);
1657    NamedDecl* ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
1658                                      TypeSourceInfo *TInfo,
1659                                      LookupResult &Previous);
1660    NamedDecl* ActOnTypedefNameDecl(Scope* S, DeclContext* DC, TypedefNameDecl *D,
1661                                    LookupResult &Previous, bool &Redeclaration);
1662    NamedDecl *ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC,
1663                                       TypeSourceInfo *TInfo,
1664                                       LookupResult &Previous,
1665                                       MultiTemplateParamsArg TemplateParamLists,
1666                                       bool &AddToScope);
1667    // Returns true if the variable declaration is a redeclaration
1668    bool CheckVariableDeclaration(VarDecl *NewVD, LookupResult &Previous);
1669    void CheckVariableDeclarationType(VarDecl *NewVD);
1670    void CheckCompleteVariableDeclaration(VarDecl *var);
1671    void MaybeSuggestAddingStaticToDecl(const FunctionDecl *D);
1672  
1673    NamedDecl* ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC,
1674                                       TypeSourceInfo *TInfo,
1675                                       LookupResult &Previous,
1676                                       MultiTemplateParamsArg TemplateParamLists,
1677                                       bool &AddToScope);
1678    bool AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD);
1679  
1680    bool CheckConstexprFunctionDecl(const FunctionDecl *FD);
1681    bool CheckConstexprFunctionBody(const FunctionDecl *FD, Stmt *Body);
1682  
1683    void DiagnoseHiddenVirtualMethods(CXXMethodDecl *MD);
1684    void FindHiddenVirtualMethods(CXXMethodDecl *MD,
1685                            SmallVectorImpl<CXXMethodDecl*> &OverloadedMethods);
1686    void NoteHiddenVirtualMethods(CXXMethodDecl *MD,
1687                            SmallVectorImpl<CXXMethodDecl*> &OverloadedMethods);
1688    // Returns true if the function declaration is a redeclaration
1689    bool CheckFunctionDeclaration(Scope *S,
1690                                  FunctionDecl *NewFD, LookupResult &Previous,
1691                                  bool IsExplicitSpecialization);
1692    void CheckMain(FunctionDecl *FD, const DeclSpec &D);
1693    void CheckMSVCRTEntryPoint(FunctionDecl *FD);
1694    Decl *ActOnParamDeclarator(Scope *S, Declarator &D);
1695    ParmVarDecl *BuildParmVarDeclForTypedef(DeclContext *DC,
1696                                            SourceLocation Loc,
1697                                            QualType T);
1698    ParmVarDecl *CheckParameter(DeclContext *DC, SourceLocation StartLoc,
1699                                SourceLocation NameLoc, IdentifierInfo *Name,
1700                                QualType T, TypeSourceInfo *TSInfo,
1701                                StorageClass SC);
1702    void ActOnParamDefaultArgument(Decl *param,
1703                                   SourceLocation EqualLoc,
1704                                   Expr *defarg);
1705    void ActOnParamUnparsedDefaultArgument(Decl *param,
1706                                           SourceLocation EqualLoc,
1707                                           SourceLocation ArgLoc);
1708    void ActOnParamDefaultArgumentError(Decl *param, SourceLocation EqualLoc);
1709    bool SetParamDefaultArgument(ParmVarDecl *Param, Expr *DefaultArg,
1710                                 SourceLocation EqualLoc);
1711  
1712    void AddInitializerToDecl(Decl *dcl, Expr *init, bool DirectInit,
1713                              bool TypeMayContainAuto);
1714    void ActOnUninitializedDecl(Decl *dcl, bool TypeMayContainAuto);
1715    void ActOnInitializerError(Decl *Dcl);
1716    void ActOnPureSpecifier(Decl *D, SourceLocation PureSpecLoc);
1717    void ActOnCXXForRangeDecl(Decl *D);
1718    StmtResult ActOnCXXForRangeIdentifier(Scope *S, SourceLocation IdentLoc,
1719                                          IdentifierInfo *Ident,
1720                                          ParsedAttributes &Attrs,
1721                                          SourceLocation AttrEnd);
1722    void SetDeclDeleted(Decl *dcl, SourceLocation DelLoc);
1723    void SetDeclDefaulted(Decl *dcl, SourceLocation DefaultLoc);
1724    void FinalizeDeclaration(Decl *D);
1725    DeclGroupPtrTy FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS,
1726                                           ArrayRef<Decl *> Group);
1727    DeclGroupPtrTy BuildDeclaratorGroup(MutableArrayRef<Decl *> Group,
1728                                        bool TypeMayContainAuto = true);
1729  
1730    /// Should be called on all declarations that might have attached
1731    /// documentation comments.
1732    void ActOnDocumentableDecl(Decl *D);
1733    void ActOnDocumentableDecls(ArrayRef<Decl *> Group);
1734  
1735    void ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D,
1736                                         SourceLocation LocAfterDecls);
1737    void CheckForFunctionRedefinition(
1738        FunctionDecl *FD, const FunctionDecl *EffectiveDefinition = nullptr,
1739        SkipBodyInfo *SkipBody = nullptr);
1740    Decl *ActOnStartOfFunctionDef(Scope *S, Declarator &D,
1741                                  MultiTemplateParamsArg TemplateParamLists,
1742                                  SkipBodyInfo *SkipBody = nullptr);
1743    Decl *ActOnStartOfFunctionDef(Scope *S, Decl *D,
1744                                  SkipBodyInfo *SkipBody = nullptr);
1745    void ActOnStartOfObjCMethodDef(Scope *S, Decl *D);
isObjCMethodDecl(Decl * D)1746    bool isObjCMethodDecl(Decl *D) {
1747      return D && isa<ObjCMethodDecl>(D);
1748    }
1749  
1750    /// \brief Determine whether we can delay parsing the body of a function or
1751    /// function template until it is used, assuming we don't care about emitting
1752    /// code for that function.
1753    ///
1754    /// This will be \c false if we may need the body of the function in the
1755    /// middle of parsing an expression (where it's impractical to switch to
1756    /// parsing a different function), for instance, if it's constexpr in C++11
1757    /// or has an 'auto' return type in C++14. These cases are essentially bugs.
1758    bool canDelayFunctionBody(const Declarator &D);
1759  
1760    /// \brief Determine whether we can skip parsing the body of a function
1761    /// definition, assuming we don't care about analyzing its body or emitting
1762    /// code for that function.
1763    ///
1764    /// This will be \c false only if we may need the body of the function in
1765    /// order to parse the rest of the program (for instance, if it is
1766    /// \c constexpr in C++11 or has an 'auto' return type in C++14).
1767    bool canSkipFunctionBody(Decl *D);
1768  
1769    void computeNRVO(Stmt *Body, sema::FunctionScopeInfo *Scope);
1770    Decl *ActOnFinishFunctionBody(Decl *Decl, Stmt *Body);
1771    Decl *ActOnFinishFunctionBody(Decl *Decl, Stmt *Body, bool IsInstantiation);
1772    Decl *ActOnSkippedFunctionBody(Decl *Decl);
1773    void ActOnFinishInlineMethodDef(CXXMethodDecl *D);
1774  
1775    /// ActOnFinishDelayedAttribute - Invoked when we have finished parsing an
1776    /// attribute for which parsing is delayed.
1777    void ActOnFinishDelayedAttribute(Scope *S, Decl *D, ParsedAttributes &Attrs);
1778  
1779    /// \brief Diagnose any unused parameters in the given sequence of
1780    /// ParmVarDecl pointers.
1781    void DiagnoseUnusedParameters(ParmVarDecl * const *Begin,
1782                                  ParmVarDecl * const *End);
1783  
1784    /// \brief Diagnose whether the size of parameters or return value of a
1785    /// function or obj-c method definition is pass-by-value and larger than a
1786    /// specified threshold.
1787    void DiagnoseSizeOfParametersAndReturnValue(ParmVarDecl * const *Begin,
1788                                                ParmVarDecl * const *End,
1789                                                QualType ReturnTy,
1790                                                NamedDecl *D);
1791  
1792    void DiagnoseInvalidJumps(Stmt *Body);
1793    Decl *ActOnFileScopeAsmDecl(Expr *expr,
1794                                SourceLocation AsmLoc,
1795                                SourceLocation RParenLoc);
1796  
1797    /// \brief Handle a C++11 empty-declaration and attribute-declaration.
1798    Decl *ActOnEmptyDeclaration(Scope *S,
1799                                AttributeList *AttrList,
1800                                SourceLocation SemiLoc);
1801  
1802    /// \brief The parser has processed a module import declaration.
1803    ///
1804    /// \param AtLoc The location of the '@' symbol, if any.
1805    ///
1806    /// \param ImportLoc The location of the 'import' keyword.
1807    ///
1808    /// \param Path The module access path.
1809    DeclResult ActOnModuleImport(SourceLocation AtLoc, SourceLocation ImportLoc,
1810                                 ModuleIdPath Path);
1811  
1812    /// \brief The parser has processed a module import translated from a
1813    /// #include or similar preprocessing directive.
1814    void ActOnModuleInclude(SourceLocation DirectiveLoc, Module *Mod);
1815  
1816    /// \brief The parsed has entered a submodule.
1817    void ActOnModuleBegin(SourceLocation DirectiveLoc, Module *Mod);
1818    /// \brief The parser has left a submodule.
1819    void ActOnModuleEnd(SourceLocation DirectiveLoc, Module *Mod);
1820  
1821    /// \brief Check if module import may be found in the current context,
1822    /// emit error if not.
1823    void diagnoseMisplacedModuleImport(Module *M, SourceLocation ImportLoc);
1824  
1825    /// \brief Create an implicit import of the given module at the given
1826    /// source location, for error recovery, if possible.
1827    ///
1828    /// This routine is typically used when an entity found by name lookup
1829    /// is actually hidden within a module that we know about but the user
1830    /// has forgotten to import.
1831    void createImplicitModuleImportForErrorRecovery(SourceLocation Loc,
1832                                                    Module *Mod);
1833  
1834    /// Kinds of missing import. Note, the values of these enumerators correspond
1835    /// to %select values in diagnostics.
1836    enum class MissingImportKind {
1837      Declaration,
1838      Definition,
1839      DefaultArgument
1840    };
1841  
1842    /// \brief Diagnose that the specified declaration needs to be visible but
1843    /// isn't, and suggest a module import that would resolve the problem.
1844    void diagnoseMissingImport(SourceLocation Loc, NamedDecl *Decl,
1845                               bool NeedDefinition, bool Recover = true);
1846    void diagnoseMissingImport(SourceLocation Loc, NamedDecl *Decl,
1847                               SourceLocation DeclLoc, ArrayRef<Module *> Modules,
1848                               MissingImportKind MIK, bool Recover);
1849  
1850    /// \brief Retrieve a suitable printing policy.
getPrintingPolicy()1851    PrintingPolicy getPrintingPolicy() const {
1852      return getPrintingPolicy(Context, PP);
1853    }
1854  
1855    /// \brief Retrieve a suitable printing policy.
1856    static PrintingPolicy getPrintingPolicy(const ASTContext &Ctx,
1857                                            const Preprocessor &PP);
1858  
1859    /// Scope actions.
1860    void ActOnPopScope(SourceLocation Loc, Scope *S);
1861    void ActOnTranslationUnitScope(Scope *S);
1862  
1863    Decl *ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS,
1864                                     DeclSpec &DS);
1865    Decl *ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS,
1866                                     DeclSpec &DS,
1867                                     MultiTemplateParamsArg TemplateParams,
1868                                     bool IsExplicitInstantiation = false);
1869  
1870    Decl *BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
1871                                      AccessSpecifier AS,
1872                                      RecordDecl *Record,
1873                                      const PrintingPolicy &Policy);
1874  
1875    Decl *BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS,
1876                                         RecordDecl *Record);
1877  
1878    bool isAcceptableTagRedeclaration(const TagDecl *Previous,
1879                                      TagTypeKind NewTag, bool isDefinition,
1880                                      SourceLocation NewTagLoc,
1881                                      const IdentifierInfo *Name);
1882  
1883    enum TagUseKind {
1884      TUK_Reference,   // Reference to a tag:  'struct foo *X;'
1885      TUK_Declaration, // Fwd decl of a tag:   'struct foo;'
1886      TUK_Definition,  // Definition of a tag: 'struct foo { int X; } Y;'
1887      TUK_Friend       // Friend declaration:  'friend struct foo;'
1888    };
1889  
1890    Decl *ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
1891                   SourceLocation KWLoc, CXXScopeSpec &SS,
1892                   IdentifierInfo *Name, SourceLocation NameLoc,
1893                   AttributeList *Attr, AccessSpecifier AS,
1894                   SourceLocation ModulePrivateLoc,
1895                   MultiTemplateParamsArg TemplateParameterLists,
1896                   bool &OwnedDecl, bool &IsDependent,
1897                   SourceLocation ScopedEnumKWLoc,
1898                   bool ScopedEnumUsesClassTag, TypeResult UnderlyingType,
1899                   bool IsTypeSpecifier, SkipBodyInfo *SkipBody = nullptr);
1900  
1901    Decl *ActOnTemplatedFriendTag(Scope *S, SourceLocation FriendLoc,
1902                                  unsigned TagSpec, SourceLocation TagLoc,
1903                                  CXXScopeSpec &SS,
1904                                  IdentifierInfo *Name, SourceLocation NameLoc,
1905                                  AttributeList *Attr,
1906                                  MultiTemplateParamsArg TempParamLists);
1907  
1908    TypeResult ActOnDependentTag(Scope *S,
1909                                 unsigned TagSpec,
1910                                 TagUseKind TUK,
1911                                 const CXXScopeSpec &SS,
1912                                 IdentifierInfo *Name,
1913                                 SourceLocation TagLoc,
1914                                 SourceLocation NameLoc);
1915  
1916    void ActOnDefs(Scope *S, Decl *TagD, SourceLocation DeclStart,
1917                   IdentifierInfo *ClassName,
1918                   SmallVectorImpl<Decl *> &Decls);
1919    Decl *ActOnField(Scope *S, Decl *TagD, SourceLocation DeclStart,
1920                     Declarator &D, Expr *BitfieldWidth);
1921  
1922    FieldDecl *HandleField(Scope *S, RecordDecl *TagD, SourceLocation DeclStart,
1923                           Declarator &D, Expr *BitfieldWidth,
1924                           InClassInitStyle InitStyle,
1925                           AccessSpecifier AS);
1926    MSPropertyDecl *HandleMSProperty(Scope *S, RecordDecl *TagD,
1927                                     SourceLocation DeclStart,
1928                                     Declarator &D, Expr *BitfieldWidth,
1929                                     InClassInitStyle InitStyle,
1930                                     AccessSpecifier AS,
1931                                     AttributeList *MSPropertyAttr);
1932  
1933    FieldDecl *CheckFieldDecl(DeclarationName Name, QualType T,
1934                              TypeSourceInfo *TInfo,
1935                              RecordDecl *Record, SourceLocation Loc,
1936                              bool Mutable, Expr *BitfieldWidth,
1937                              InClassInitStyle InitStyle,
1938                              SourceLocation TSSL,
1939                              AccessSpecifier AS, NamedDecl *PrevDecl,
1940                              Declarator *D = nullptr);
1941  
1942    bool CheckNontrivialField(FieldDecl *FD);
1943    void DiagnoseNontrivial(const CXXRecordDecl *Record, CXXSpecialMember CSM);
1944    bool SpecialMemberIsTrivial(CXXMethodDecl *MD, CXXSpecialMember CSM,
1945                                bool Diagnose = false);
1946    CXXSpecialMember getSpecialMember(const CXXMethodDecl *MD);
1947    void ActOnLastBitfield(SourceLocation DeclStart,
1948                           SmallVectorImpl<Decl *> &AllIvarDecls);
1949    Decl *ActOnIvar(Scope *S, SourceLocation DeclStart,
1950                    Declarator &D, Expr *BitfieldWidth,
1951                    tok::ObjCKeywordKind visibility);
1952  
1953    // This is used for both record definitions and ObjC interface declarations.
1954    void ActOnFields(Scope* S, SourceLocation RecLoc, Decl *TagDecl,
1955                     ArrayRef<Decl *> Fields,
1956                     SourceLocation LBrac, SourceLocation RBrac,
1957                     AttributeList *AttrList);
1958  
1959    /// ActOnTagStartDefinition - Invoked when we have entered the
1960    /// scope of a tag's definition (e.g., for an enumeration, class,
1961    /// struct, or union).
1962    void ActOnTagStartDefinition(Scope *S, Decl *TagDecl);
1963  
1964    typedef void *SkippedDefinitionContext;
1965  
1966    /// \brief Invoked when we enter a tag definition that we're skipping.
1967    SkippedDefinitionContext ActOnTagStartSkippedDefinition(Scope *S, Decl *TD);
1968  
1969    Decl *ActOnObjCContainerStartDefinition(Decl *IDecl);
1970  
1971    /// ActOnStartCXXMemberDeclarations - Invoked when we have parsed a
1972    /// C++ record definition's base-specifiers clause and are starting its
1973    /// member declarations.
1974    void ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagDecl,
1975                                         SourceLocation FinalLoc,
1976                                         bool IsFinalSpelledSealed,
1977                                         SourceLocation LBraceLoc);
1978  
1979    /// ActOnTagFinishDefinition - Invoked once we have finished parsing
1980    /// the definition of a tag (enumeration, class, struct, or union).
1981    void ActOnTagFinishDefinition(Scope *S, Decl *TagDecl,
1982                                  SourceLocation RBraceLoc);
1983  
1984    void ActOnTagFinishSkippedDefinition(SkippedDefinitionContext Context);
1985  
1986    void ActOnObjCContainerFinishDefinition();
1987  
1988    /// \brief Invoked when we must temporarily exit the objective-c container
1989    /// scope for parsing/looking-up C constructs.
1990    ///
1991    /// Must be followed by a call to \see ActOnObjCReenterContainerContext
1992    void ActOnObjCTemporaryExitContainerContext(DeclContext *DC);
1993    void ActOnObjCReenterContainerContext(DeclContext *DC);
1994  
1995    /// ActOnTagDefinitionError - Invoked when there was an unrecoverable
1996    /// error parsing the definition of a tag.
1997    void ActOnTagDefinitionError(Scope *S, Decl *TagDecl);
1998  
1999    EnumConstantDecl *CheckEnumConstant(EnumDecl *Enum,
2000                                        EnumConstantDecl *LastEnumConst,
2001                                        SourceLocation IdLoc,
2002                                        IdentifierInfo *Id,
2003                                        Expr *val);
2004    bool CheckEnumUnderlyingType(TypeSourceInfo *TI);
2005    bool CheckEnumRedeclaration(SourceLocation EnumLoc, bool IsScoped,
2006                                QualType EnumUnderlyingTy,
2007                                bool EnumUnderlyingIsImplicit,
2008                                const EnumDecl *Prev);
2009  
2010    /// Determine whether the body of an anonymous enumeration should be skipped.
2011    /// \param II The name of the first enumerator.
2012    SkipBodyInfo shouldSkipAnonEnumBody(Scope *S, IdentifierInfo *II,
2013                                        SourceLocation IILoc);
2014  
2015    Decl *ActOnEnumConstant(Scope *S, Decl *EnumDecl, Decl *LastEnumConstant,
2016                            SourceLocation IdLoc, IdentifierInfo *Id,
2017                            AttributeList *Attrs,
2018                            SourceLocation EqualLoc, Expr *Val);
2019    void ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc,
2020                       SourceLocation RBraceLoc, Decl *EnumDecl,
2021                       ArrayRef<Decl *> Elements,
2022                       Scope *S, AttributeList *Attr);
2023  
2024    DeclContext *getContainingDC(DeclContext *DC);
2025  
2026    /// Set the current declaration context until it gets popped.
2027    void PushDeclContext(Scope *S, DeclContext *DC);
2028    void PopDeclContext();
2029  
2030    /// EnterDeclaratorContext - Used when we must lookup names in the context
2031    /// of a declarator's nested name specifier.
2032    void EnterDeclaratorContext(Scope *S, DeclContext *DC);
2033    void ExitDeclaratorContext(Scope *S);
2034  
2035    /// Push the parameters of D, which must be a function, into scope.
2036    void ActOnReenterFunctionContext(Scope* S, Decl* D);
2037    void ActOnExitFunctionContext();
2038  
2039    DeclContext *getFunctionLevelDeclContext();
2040  
2041    /// getCurFunctionDecl - If inside of a function body, this returns a pointer
2042    /// to the function decl for the function being parsed.  If we're currently
2043    /// in a 'block', this returns the containing context.
2044    FunctionDecl *getCurFunctionDecl();
2045  
2046    /// getCurMethodDecl - If inside of a method body, this returns a pointer to
2047    /// the method decl for the method being parsed.  If we're currently
2048    /// in a 'block', this returns the containing context.
2049    ObjCMethodDecl *getCurMethodDecl();
2050  
2051    /// getCurFunctionOrMethodDecl - Return the Decl for the current ObjC method
2052    /// or C function we're in, otherwise return null.  If we're currently
2053    /// in a 'block', this returns the containing context.
2054    NamedDecl *getCurFunctionOrMethodDecl();
2055  
2056    /// Add this decl to the scope shadowed decl chains.
2057    void PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext = true);
2058  
2059    /// \brief Make the given externally-produced declaration visible at the
2060    /// top level scope.
2061    ///
2062    /// \param D The externally-produced declaration to push.
2063    ///
2064    /// \param Name The name of the externally-produced declaration.
2065    void pushExternalDeclIntoScope(NamedDecl *D, DeclarationName Name);
2066  
2067    /// isDeclInScope - If 'Ctx' is a function/method, isDeclInScope returns true
2068    /// if 'D' is in Scope 'S', otherwise 'S' is ignored and isDeclInScope returns
2069    /// true if 'D' belongs to the given declaration context.
2070    ///
2071    /// \param AllowInlineNamespace If \c true, allow the declaration to be in the
2072    ///        enclosing namespace set of the context, rather than contained
2073    ///        directly within it.
2074    bool isDeclInScope(NamedDecl *D, DeclContext *Ctx, Scope *S = nullptr,
2075                       bool AllowInlineNamespace = false);
2076  
2077    /// Finds the scope corresponding to the given decl context, if it
2078    /// happens to be an enclosing scope.  Otherwise return NULL.
2079    static Scope *getScopeForDeclContext(Scope *S, DeclContext *DC);
2080  
2081    /// Subroutines of ActOnDeclarator().
2082    TypedefDecl *ParseTypedefDecl(Scope *S, Declarator &D, QualType T,
2083                                  TypeSourceInfo *TInfo);
2084    bool isIncompatibleTypedef(TypeDecl *Old, TypedefNameDecl *New);
2085  
2086    /// \brief Describes the kind of merge to perform for availability
2087    /// attributes (including "deprecated", "unavailable", and "availability").
2088    enum AvailabilityMergeKind {
2089      /// \brief Don't merge availability attributes at all.
2090      AMK_None,
2091      /// \brief Merge availability attributes for a redeclaration, which requires
2092      /// an exact match.
2093      AMK_Redeclaration,
2094      /// \brief Merge availability attributes for an override, which requires
2095      /// an exact match or a weakening of constraints.
2096      AMK_Override,
2097      /// \brief Merge availability attributes for an implementation of
2098      /// a protocol requirement.
2099      AMK_ProtocolImplementation,
2100    };
2101  
2102    /// Attribute merging methods. Return true if a new attribute was added.
2103    AvailabilityAttr *mergeAvailabilityAttr(NamedDecl *D, SourceRange Range,
2104                                            IdentifierInfo *Platform,
2105                                            VersionTuple Introduced,
2106                                            VersionTuple Deprecated,
2107                                            VersionTuple Obsoleted,
2108                                            bool IsUnavailable,
2109                                            StringRef Message,
2110                                            AvailabilityMergeKind AMK,
2111                                            unsigned AttrSpellingListIndex);
2112    TypeVisibilityAttr *mergeTypeVisibilityAttr(Decl *D, SourceRange Range,
2113                                         TypeVisibilityAttr::VisibilityType Vis,
2114                                                unsigned AttrSpellingListIndex);
2115    VisibilityAttr *mergeVisibilityAttr(Decl *D, SourceRange Range,
2116                                        VisibilityAttr::VisibilityType Vis,
2117                                        unsigned AttrSpellingListIndex);
2118    DLLImportAttr *mergeDLLImportAttr(Decl *D, SourceRange Range,
2119                                      unsigned AttrSpellingListIndex);
2120    DLLExportAttr *mergeDLLExportAttr(Decl *D, SourceRange Range,
2121                                      unsigned AttrSpellingListIndex);
2122    MSInheritanceAttr *
2123    mergeMSInheritanceAttr(Decl *D, SourceRange Range, bool BestCase,
2124                           unsigned AttrSpellingListIndex,
2125                           MSInheritanceAttr::Spelling SemanticSpelling);
2126    FormatAttr *mergeFormatAttr(Decl *D, SourceRange Range,
2127                                IdentifierInfo *Format, int FormatIdx,
2128                                int FirstArg, unsigned AttrSpellingListIndex);
2129    SectionAttr *mergeSectionAttr(Decl *D, SourceRange Range, StringRef Name,
2130                                  unsigned AttrSpellingListIndex);
2131    AlwaysInlineAttr *mergeAlwaysInlineAttr(Decl *D, SourceRange Range,
2132                                            IdentifierInfo *Ident,
2133                                            unsigned AttrSpellingListIndex);
2134    MinSizeAttr *mergeMinSizeAttr(Decl *D, SourceRange Range,
2135                                  unsigned AttrSpellingListIndex);
2136    OptimizeNoneAttr *mergeOptimizeNoneAttr(Decl *D, SourceRange Range,
2137                                            unsigned AttrSpellingListIndex);
2138    InternalLinkageAttr *mergeInternalLinkageAttr(Decl *D, SourceRange Range,
2139                                                  IdentifierInfo *Ident,
2140                                                  unsigned AttrSpellingListIndex);
2141    CommonAttr *mergeCommonAttr(Decl *D, SourceRange Range, IdentifierInfo *Ident,
2142                                unsigned AttrSpellingListIndex);
2143  
2144    void mergeDeclAttributes(NamedDecl *New, Decl *Old,
2145                             AvailabilityMergeKind AMK = AMK_Redeclaration);
2146    void MergeTypedefNameDecl(Scope *S, TypedefNameDecl *New,
2147                              LookupResult &OldDecls);
2148    bool MergeFunctionDecl(FunctionDecl *New, NamedDecl *&Old, Scope *S,
2149                           bool MergeTypeWithOld);
2150    bool MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old,
2151                                      Scope *S, bool MergeTypeWithOld);
2152    void mergeObjCMethodDecls(ObjCMethodDecl *New, ObjCMethodDecl *Old);
2153    void MergeVarDecl(VarDecl *New, LookupResult &Previous);
2154    void MergeVarDeclTypes(VarDecl *New, VarDecl *Old, bool MergeTypeWithOld);
2155    void MergeVarDeclExceptionSpecs(VarDecl *New, VarDecl *Old);
2156    bool MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old, Scope *S);
2157  
2158    // AssignmentAction - This is used by all the assignment diagnostic functions
2159    // to represent what is actually causing the operation
2160    enum AssignmentAction {
2161      AA_Assigning,
2162      AA_Passing,
2163      AA_Returning,
2164      AA_Converting,
2165      AA_Initializing,
2166      AA_Sending,
2167      AA_Casting,
2168      AA_Passing_CFAudited
2169    };
2170  
2171    /// C++ Overloading.
2172    enum OverloadKind {
2173      /// This is a legitimate overload: the existing declarations are
2174      /// functions or function templates with different signatures.
2175      Ovl_Overload,
2176  
2177      /// This is not an overload because the signature exactly matches
2178      /// an existing declaration.
2179      Ovl_Match,
2180  
2181      /// This is not an overload because the lookup results contain a
2182      /// non-function.
2183      Ovl_NonFunction
2184    };
2185    OverloadKind CheckOverload(Scope *S,
2186                               FunctionDecl *New,
2187                               const LookupResult &OldDecls,
2188                               NamedDecl *&OldDecl,
2189                               bool IsForUsingDecl);
2190    bool IsOverload(FunctionDecl *New, FunctionDecl *Old, bool IsForUsingDecl);
2191  
2192    /// \brief Checks availability of the function depending on the current
2193    /// function context.Inside an unavailable function,unavailability is ignored.
2194    ///
2195    /// \returns true if \p FD is unavailable and current context is inside
2196    /// an available function, false otherwise.
2197    bool isFunctionConsideredUnavailable(FunctionDecl *FD);
2198  
2199    ImplicitConversionSequence
2200    TryImplicitConversion(Expr *From, QualType ToType,
2201                          bool SuppressUserConversions,
2202                          bool AllowExplicit,
2203                          bool InOverloadResolution,
2204                          bool CStyle,
2205                          bool AllowObjCWritebackConversion);
2206  
2207    bool IsIntegralPromotion(Expr *From, QualType FromType, QualType ToType);
2208    bool IsFloatingPointPromotion(QualType FromType, QualType ToType);
2209    bool IsComplexPromotion(QualType FromType, QualType ToType);
2210    bool IsPointerConversion(Expr *From, QualType FromType, QualType ToType,
2211                             bool InOverloadResolution,
2212                             QualType& ConvertedType, bool &IncompatibleObjC);
2213    bool isObjCPointerConversion(QualType FromType, QualType ToType,
2214                                 QualType& ConvertedType, bool &IncompatibleObjC);
2215    bool isObjCWritebackConversion(QualType FromType, QualType ToType,
2216                                   QualType &ConvertedType);
2217    bool IsBlockPointerConversion(QualType FromType, QualType ToType,
2218                                  QualType& ConvertedType);
2219    bool FunctionParamTypesAreEqual(const FunctionProtoType *OldType,
2220                                    const FunctionProtoType *NewType,
2221                                    unsigned *ArgPos = nullptr);
2222    void HandleFunctionTypeMismatch(PartialDiagnostic &PDiag,
2223                                    QualType FromType, QualType ToType);
2224  
2225    void maybeExtendBlockObject(ExprResult &E);
2226    CastKind PrepareCastToObjCObjectPointer(ExprResult &E);
2227    bool CheckPointerConversion(Expr *From, QualType ToType,
2228                                CastKind &Kind,
2229                                CXXCastPath& BasePath,
2230                                bool IgnoreBaseAccess);
2231    bool IsMemberPointerConversion(Expr *From, QualType FromType, QualType ToType,
2232                                   bool InOverloadResolution,
2233                                   QualType &ConvertedType);
2234    bool CheckMemberPointerConversion(Expr *From, QualType ToType,
2235                                      CastKind &Kind,
2236                                      CXXCastPath &BasePath,
2237                                      bool IgnoreBaseAccess);
2238    bool IsQualificationConversion(QualType FromType, QualType ToType,
2239                                   bool CStyle, bool &ObjCLifetimeConversion);
2240    bool IsNoReturnConversion(QualType FromType, QualType ToType,
2241                              QualType &ResultTy);
2242    bool DiagnoseMultipleUserDefinedConversion(Expr *From, QualType ToType);
2243    bool isSameOrCompatibleFunctionType(CanQualType Param, CanQualType Arg);
2244  
2245    ExprResult PerformMoveOrCopyInitialization(const InitializedEntity &Entity,
2246                                               const VarDecl *NRVOCandidate,
2247                                               QualType ResultType,
2248                                               Expr *Value,
2249                                               bool AllowNRVO = true);
2250  
2251    bool CanPerformCopyInitialization(const InitializedEntity &Entity,
2252                                      ExprResult Init);
2253    ExprResult PerformCopyInitialization(const InitializedEntity &Entity,
2254                                         SourceLocation EqualLoc,
2255                                         ExprResult Init,
2256                                         bool TopLevelOfInitList = false,
2257                                         bool AllowExplicit = false);
2258    ExprResult PerformObjectArgumentInitialization(Expr *From,
2259                                                   NestedNameSpecifier *Qualifier,
2260                                                   NamedDecl *FoundDecl,
2261                                                   CXXMethodDecl *Method);
2262  
2263    ExprResult PerformContextuallyConvertToBool(Expr *From);
2264    ExprResult PerformContextuallyConvertToObjCPointer(Expr *From);
2265  
2266    /// Contexts in which a converted constant expression is required.
2267    enum CCEKind {
2268      CCEK_CaseValue,   ///< Expression in a case label.
2269      CCEK_Enumerator,  ///< Enumerator value with fixed underlying type.
2270      CCEK_TemplateArg, ///< Value of a non-type template parameter.
2271      CCEK_NewExpr      ///< Constant expression in a noptr-new-declarator.
2272    };
2273    ExprResult CheckConvertedConstantExpression(Expr *From, QualType T,
2274                                                llvm::APSInt &Value, CCEKind CCE);
2275    ExprResult CheckConvertedConstantExpression(Expr *From, QualType T,
2276                                                APValue &Value, CCEKind CCE);
2277  
2278    /// \brief Abstract base class used to perform a contextual implicit
2279    /// conversion from an expression to any type passing a filter.
2280    class ContextualImplicitConverter {
2281    public:
2282      bool Suppress;
2283      bool SuppressConversion;
2284  
2285      ContextualImplicitConverter(bool Suppress = false,
2286                                  bool SuppressConversion = false)
Suppress(Suppress)2287          : Suppress(Suppress), SuppressConversion(SuppressConversion) {}
2288  
2289      /// \brief Determine whether the specified type is a valid destination type
2290      /// for this conversion.
2291      virtual bool match(QualType T) = 0;
2292  
2293      /// \brief Emits a diagnostic complaining that the expression does not have
2294      /// integral or enumeration type.
2295      virtual SemaDiagnosticBuilder
2296      diagnoseNoMatch(Sema &S, SourceLocation Loc, QualType T) = 0;
2297  
2298      /// \brief Emits a diagnostic when the expression has incomplete class type.
2299      virtual SemaDiagnosticBuilder
2300      diagnoseIncomplete(Sema &S, SourceLocation Loc, QualType T) = 0;
2301  
2302      /// \brief Emits a diagnostic when the only matching conversion function
2303      /// is explicit.
2304      virtual SemaDiagnosticBuilder diagnoseExplicitConv(
2305          Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) = 0;
2306  
2307      /// \brief Emits a note for the explicit conversion function.
2308      virtual SemaDiagnosticBuilder
2309      noteExplicitConv(Sema &S, CXXConversionDecl *Conv, QualType ConvTy) = 0;
2310  
2311      /// \brief Emits a diagnostic when there are multiple possible conversion
2312      /// functions.
2313      virtual SemaDiagnosticBuilder
2314      diagnoseAmbiguous(Sema &S, SourceLocation Loc, QualType T) = 0;
2315  
2316      /// \brief Emits a note for one of the candidate conversions.
2317      virtual SemaDiagnosticBuilder
2318      noteAmbiguous(Sema &S, CXXConversionDecl *Conv, QualType ConvTy) = 0;
2319  
2320      /// \brief Emits a diagnostic when we picked a conversion function
2321      /// (for cases when we are not allowed to pick a conversion function).
2322      virtual SemaDiagnosticBuilder diagnoseConversion(
2323          Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) = 0;
2324  
~ContextualImplicitConverter()2325      virtual ~ContextualImplicitConverter() {}
2326    };
2327  
2328    class ICEConvertDiagnoser : public ContextualImplicitConverter {
2329      bool AllowScopedEnumerations;
2330  
2331    public:
ICEConvertDiagnoser(bool AllowScopedEnumerations,bool Suppress,bool SuppressConversion)2332      ICEConvertDiagnoser(bool AllowScopedEnumerations,
2333                          bool Suppress, bool SuppressConversion)
2334          : ContextualImplicitConverter(Suppress, SuppressConversion),
2335            AllowScopedEnumerations(AllowScopedEnumerations) {}
2336  
2337      /// Match an integral or (possibly scoped) enumeration type.
2338      bool match(QualType T) override;
2339  
2340      SemaDiagnosticBuilder
diagnoseNoMatch(Sema & S,SourceLocation Loc,QualType T)2341      diagnoseNoMatch(Sema &S, SourceLocation Loc, QualType T) override {
2342        return diagnoseNotInt(S, Loc, T);
2343      }
2344  
2345      /// \brief Emits a diagnostic complaining that the expression does not have
2346      /// integral or enumeration type.
2347      virtual SemaDiagnosticBuilder
2348      diagnoseNotInt(Sema &S, SourceLocation Loc, QualType T) = 0;
2349    };
2350  
2351    /// Perform a contextual implicit conversion.
2352    ExprResult PerformContextualImplicitConversion(
2353        SourceLocation Loc, Expr *FromE, ContextualImplicitConverter &Converter);
2354  
2355  
2356    enum ObjCSubscriptKind {
2357      OS_Array,
2358      OS_Dictionary,
2359      OS_Error
2360    };
2361    ObjCSubscriptKind CheckSubscriptingKind(Expr *FromE);
2362  
2363    // Note that LK_String is intentionally after the other literals, as
2364    // this is used for diagnostics logic.
2365    enum ObjCLiteralKind {
2366      LK_Array,
2367      LK_Dictionary,
2368      LK_Numeric,
2369      LK_Boxed,
2370      LK_String,
2371      LK_Block,
2372      LK_None
2373    };
2374    ObjCLiteralKind CheckLiteralKind(Expr *FromE);
2375  
2376    ExprResult PerformObjectMemberConversion(Expr *From,
2377                                             NestedNameSpecifier *Qualifier,
2378                                             NamedDecl *FoundDecl,
2379                                             NamedDecl *Member);
2380  
2381    // Members have to be NamespaceDecl* or TranslationUnitDecl*.
2382    // TODO: make this is a typesafe union.
2383    typedef llvm::SmallPtrSet<DeclContext   *, 16> AssociatedNamespaceSet;
2384    typedef llvm::SmallPtrSet<CXXRecordDecl *, 16> AssociatedClassSet;
2385  
2386    void AddOverloadCandidate(FunctionDecl *Function,
2387                              DeclAccessPair FoundDecl,
2388                              ArrayRef<Expr *> Args,
2389                              OverloadCandidateSet& CandidateSet,
2390                              bool SuppressUserConversions = false,
2391                              bool PartialOverloading = false,
2392                              bool AllowExplicit = false);
2393    void AddFunctionCandidates(const UnresolvedSetImpl &Functions,
2394                        ArrayRef<Expr *> Args,
2395                        OverloadCandidateSet &CandidateSet,
2396                        TemplateArgumentListInfo *ExplicitTemplateArgs = nullptr,
2397                        bool SuppressUserConversions = false,
2398                        bool PartialOverloading = false);
2399    void AddMethodCandidate(DeclAccessPair FoundDecl,
2400                            QualType ObjectType,
2401                            Expr::Classification ObjectClassification,
2402                            ArrayRef<Expr *> Args,
2403                            OverloadCandidateSet& CandidateSet,
2404                            bool SuppressUserConversion = false);
2405    void AddMethodCandidate(CXXMethodDecl *Method,
2406                            DeclAccessPair FoundDecl,
2407                            CXXRecordDecl *ActingContext, QualType ObjectType,
2408                            Expr::Classification ObjectClassification,
2409                            ArrayRef<Expr *> Args,
2410                            OverloadCandidateSet& CandidateSet,
2411                            bool SuppressUserConversions = false,
2412                            bool PartialOverloading = false);
2413    void AddMethodTemplateCandidate(FunctionTemplateDecl *MethodTmpl,
2414                                    DeclAccessPair FoundDecl,
2415                                    CXXRecordDecl *ActingContext,
2416                                   TemplateArgumentListInfo *ExplicitTemplateArgs,
2417                                    QualType ObjectType,
2418                                    Expr::Classification ObjectClassification,
2419                                    ArrayRef<Expr *> Args,
2420                                    OverloadCandidateSet& CandidateSet,
2421                                    bool SuppressUserConversions = false,
2422                                    bool PartialOverloading = false);
2423    void AddTemplateOverloadCandidate(FunctionTemplateDecl *FunctionTemplate,
2424                                      DeclAccessPair FoundDecl,
2425                                   TemplateArgumentListInfo *ExplicitTemplateArgs,
2426                                      ArrayRef<Expr *> Args,
2427                                      OverloadCandidateSet& CandidateSet,
2428                                      bool SuppressUserConversions = false,
2429                                      bool PartialOverloading = false);
2430    void AddConversionCandidate(CXXConversionDecl *Conversion,
2431                                DeclAccessPair FoundDecl,
2432                                CXXRecordDecl *ActingContext,
2433                                Expr *From, QualType ToType,
2434                                OverloadCandidateSet& CandidateSet,
2435                                bool AllowObjCConversionOnExplicit);
2436    void AddTemplateConversionCandidate(FunctionTemplateDecl *FunctionTemplate,
2437                                        DeclAccessPair FoundDecl,
2438                                        CXXRecordDecl *ActingContext,
2439                                        Expr *From, QualType ToType,
2440                                        OverloadCandidateSet &CandidateSet,
2441                                        bool AllowObjCConversionOnExplicit);
2442    void AddSurrogateCandidate(CXXConversionDecl *Conversion,
2443                               DeclAccessPair FoundDecl,
2444                               CXXRecordDecl *ActingContext,
2445                               const FunctionProtoType *Proto,
2446                               Expr *Object, ArrayRef<Expr *> Args,
2447                               OverloadCandidateSet& CandidateSet);
2448    void AddMemberOperatorCandidates(OverloadedOperatorKind Op,
2449                                     SourceLocation OpLoc, ArrayRef<Expr *> Args,
2450                                     OverloadCandidateSet& CandidateSet,
2451                                     SourceRange OpRange = SourceRange());
2452    void AddBuiltinCandidate(QualType ResultTy, QualType *ParamTys,
2453                             ArrayRef<Expr *> Args,
2454                             OverloadCandidateSet& CandidateSet,
2455                             bool IsAssignmentOperator = false,
2456                             unsigned NumContextualBoolArguments = 0);
2457    void AddBuiltinOperatorCandidates(OverloadedOperatorKind Op,
2458                                      SourceLocation OpLoc, ArrayRef<Expr *> Args,
2459                                      OverloadCandidateSet& CandidateSet);
2460    void AddArgumentDependentLookupCandidates(DeclarationName Name,
2461                                              SourceLocation Loc,
2462                                              ArrayRef<Expr *> Args,
2463                                  TemplateArgumentListInfo *ExplicitTemplateArgs,
2464                                              OverloadCandidateSet& CandidateSet,
2465                                              bool PartialOverloading = false);
2466  
2467    // Emit as a 'note' the specific overload candidate
2468    void NoteOverloadCandidate(FunctionDecl *Fn, QualType DestType = QualType(),
2469                               bool TakingAddress = false);
2470  
2471    // Emit as a series of 'note's all template and non-templates identified by
2472    // the expression Expr
2473    void NoteAllOverloadCandidates(Expr *E, QualType DestType = QualType(),
2474                                   bool TakingAddress = false);
2475  
2476    /// Check the enable_if expressions on the given function. Returns the first
2477    /// failing attribute, or NULL if they were all successful.
2478    EnableIfAttr *CheckEnableIf(FunctionDecl *Function, ArrayRef<Expr *> Args,
2479                                bool MissingImplicitThis = false);
2480  
2481    /// Returns whether the given function's address can be taken or not,
2482    /// optionally emitting a diagnostic if the address can't be taken.
2483    ///
2484    /// Returns false if taking the address of the function is illegal.
2485    bool checkAddressOfFunctionIsAvailable(const FunctionDecl *Function,
2486                                           bool Complain = false,
2487                                           SourceLocation Loc = SourceLocation());
2488  
2489    // [PossiblyAFunctionType]  -->   [Return]
2490    // NonFunctionType --> NonFunctionType
2491    // R (A) --> R(A)
2492    // R (*)(A) --> R (A)
2493    // R (&)(A) --> R (A)
2494    // R (S::*)(A) --> R (A)
2495    QualType ExtractUnqualifiedFunctionType(QualType PossiblyAFunctionType);
2496  
2497    FunctionDecl *
2498    ResolveAddressOfOverloadedFunction(Expr *AddressOfExpr,
2499                                       QualType TargetType,
2500                                       bool Complain,
2501                                       DeclAccessPair &Found,
2502                                       bool *pHadMultipleCandidates = nullptr);
2503  
2504    FunctionDecl *
2505    ResolveSingleFunctionTemplateSpecialization(OverloadExpr *ovl,
2506                                                bool Complain = false,
2507                                                DeclAccessPair *Found = nullptr);
2508  
2509    bool ResolveAndFixSingleFunctionTemplateSpecialization(
2510                        ExprResult &SrcExpr,
2511                        bool DoFunctionPointerConverion = false,
2512                        bool Complain = false,
2513                        SourceRange OpRangeForComplaining = SourceRange(),
2514                        QualType DestTypeForComplaining = QualType(),
2515                        unsigned DiagIDForComplaining = 0);
2516  
2517  
2518    Expr *FixOverloadedFunctionReference(Expr *E,
2519                                         DeclAccessPair FoundDecl,
2520                                         FunctionDecl *Fn);
2521    ExprResult FixOverloadedFunctionReference(ExprResult,
2522                                              DeclAccessPair FoundDecl,
2523                                              FunctionDecl *Fn);
2524  
2525    void AddOverloadedCallCandidates(UnresolvedLookupExpr *ULE,
2526                                     ArrayRef<Expr *> Args,
2527                                     OverloadCandidateSet &CandidateSet,
2528                                     bool PartialOverloading = false);
2529  
2530    // An enum used to represent the different possible results of building a
2531    // range-based for loop.
2532    enum ForRangeStatus {
2533      FRS_Success,
2534      FRS_NoViableFunction,
2535      FRS_DiagnosticIssued
2536    };
2537  
2538    ForRangeStatus BuildForRangeBeginEndCall(SourceLocation Loc,
2539                                             SourceLocation RangeLoc,
2540                                             const DeclarationNameInfo &NameInfo,
2541                                             LookupResult &MemberLookup,
2542                                             OverloadCandidateSet *CandidateSet,
2543                                             Expr *Range, ExprResult *CallExpr);
2544  
2545    ExprResult BuildOverloadedCallExpr(Scope *S, Expr *Fn,
2546                                       UnresolvedLookupExpr *ULE,
2547                                       SourceLocation LParenLoc,
2548                                       MultiExprArg Args,
2549                                       SourceLocation RParenLoc,
2550                                       Expr *ExecConfig,
2551                                       bool AllowTypoCorrection=true);
2552  
2553    bool buildOverloadedCallSet(Scope *S, Expr *Fn, UnresolvedLookupExpr *ULE,
2554                                MultiExprArg Args, SourceLocation RParenLoc,
2555                                OverloadCandidateSet *CandidateSet,
2556                                ExprResult *Result);
2557  
2558    ExprResult CreateOverloadedUnaryOp(SourceLocation OpLoc,
2559                                       UnaryOperatorKind Opc,
2560                                       const UnresolvedSetImpl &Fns,
2561                                       Expr *input);
2562  
2563    ExprResult CreateOverloadedBinOp(SourceLocation OpLoc,
2564                                     BinaryOperatorKind Opc,
2565                                     const UnresolvedSetImpl &Fns,
2566                                     Expr *LHS, Expr *RHS);
2567  
2568    ExprResult CreateOverloadedArraySubscriptExpr(SourceLocation LLoc,
2569                                                  SourceLocation RLoc,
2570                                                  Expr *Base,Expr *Idx);
2571  
2572    ExprResult
2573    BuildCallToMemberFunction(Scope *S, Expr *MemExpr,
2574                              SourceLocation LParenLoc,
2575                              MultiExprArg Args,
2576                              SourceLocation RParenLoc);
2577    ExprResult
2578    BuildCallToObjectOfClassType(Scope *S, Expr *Object, SourceLocation LParenLoc,
2579                                 MultiExprArg Args,
2580                                 SourceLocation RParenLoc);
2581  
2582    ExprResult BuildOverloadedArrowExpr(Scope *S, Expr *Base,
2583                                        SourceLocation OpLoc,
2584                                        bool *NoArrowOperatorFound = nullptr);
2585  
2586    /// CheckCallReturnType - Checks that a call expression's return type is
2587    /// complete. Returns true on failure. The location passed in is the location
2588    /// that best represents the call.
2589    bool CheckCallReturnType(QualType ReturnType, SourceLocation Loc,
2590                             CallExpr *CE, FunctionDecl *FD);
2591  
2592    /// Helpers for dealing with blocks and functions.
2593    bool CheckParmsForFunctionDef(ParmVarDecl *const *Param,
2594                                  ParmVarDecl *const *ParamEnd,
2595                                  bool CheckParameterNames);
2596    void CheckCXXDefaultArguments(FunctionDecl *FD);
2597    void CheckExtraCXXDefaultArguments(Declarator &D);
2598    Scope *getNonFieldDeclScope(Scope *S);
2599  
2600    /// \name Name lookup
2601    ///
2602    /// These routines provide name lookup that is used during semantic
2603    /// analysis to resolve the various kinds of names (identifiers,
2604    /// overloaded operator names, constructor names, etc.) into zero or
2605    /// more declarations within a particular scope. The major entry
2606    /// points are LookupName, which performs unqualified name lookup,
2607    /// and LookupQualifiedName, which performs qualified name lookup.
2608    ///
2609    /// All name lookup is performed based on some specific criteria,
2610    /// which specify what names will be visible to name lookup and how
2611    /// far name lookup should work. These criteria are important both
2612    /// for capturing language semantics (certain lookups will ignore
2613    /// certain names, for example) and for performance, since name
2614    /// lookup is often a bottleneck in the compilation of C++. Name
2615    /// lookup criteria is specified via the LookupCriteria enumeration.
2616    ///
2617    /// The results of name lookup can vary based on the kind of name
2618    /// lookup performed, the current language, and the translation
2619    /// unit. In C, for example, name lookup will either return nothing
2620    /// (no entity found) or a single declaration. In C++, name lookup
2621    /// can additionally refer to a set of overloaded functions or
2622    /// result in an ambiguity. All of the possible results of name
2623    /// lookup are captured by the LookupResult class, which provides
2624    /// the ability to distinguish among them.
2625    //@{
2626  
2627    /// @brief Describes the kind of name lookup to perform.
2628    enum LookupNameKind {
2629      /// Ordinary name lookup, which finds ordinary names (functions,
2630      /// variables, typedefs, etc.) in C and most kinds of names
2631      /// (functions, variables, members, types, etc.) in C++.
2632      LookupOrdinaryName = 0,
2633      /// Tag name lookup, which finds the names of enums, classes,
2634      /// structs, and unions.
2635      LookupTagName,
2636      /// Label name lookup.
2637      LookupLabel,
2638      /// Member name lookup, which finds the names of
2639      /// class/struct/union members.
2640      LookupMemberName,
2641      /// Look up of an operator name (e.g., operator+) for use with
2642      /// operator overloading. This lookup is similar to ordinary name
2643      /// lookup, but will ignore any declarations that are class members.
2644      LookupOperatorName,
2645      /// Look up of a name that precedes the '::' scope resolution
2646      /// operator in C++. This lookup completely ignores operator, object,
2647      /// function, and enumerator names (C++ [basic.lookup.qual]p1).
2648      LookupNestedNameSpecifierName,
2649      /// Look up a namespace name within a C++ using directive or
2650      /// namespace alias definition, ignoring non-namespace names (C++
2651      /// [basic.lookup.udir]p1).
2652      LookupNamespaceName,
2653      /// Look up all declarations in a scope with the given name,
2654      /// including resolved using declarations.  This is appropriate
2655      /// for checking redeclarations for a using declaration.
2656      LookupUsingDeclName,
2657      /// Look up an ordinary name that is going to be redeclared as a
2658      /// name with linkage. This lookup ignores any declarations that
2659      /// are outside of the current scope unless they have linkage. See
2660      /// C99 6.2.2p4-5 and C++ [basic.link]p6.
2661      LookupRedeclarationWithLinkage,
2662      /// Look up a friend of a local class. This lookup does not look
2663      /// outside the innermost non-class scope. See C++11 [class.friend]p11.
2664      LookupLocalFriendName,
2665      /// Look up the name of an Objective-C protocol.
2666      LookupObjCProtocolName,
2667      /// Look up implicit 'self' parameter of an objective-c method.
2668      LookupObjCImplicitSelfParam,
2669      /// \brief Look up any declaration with any name.
2670      LookupAnyName
2671    };
2672  
2673    /// \brief Specifies whether (or how) name lookup is being performed for a
2674    /// redeclaration (vs. a reference).
2675    enum RedeclarationKind {
2676      /// \brief The lookup is a reference to this name that is not for the
2677      /// purpose of redeclaring the name.
2678      NotForRedeclaration = 0,
2679      /// \brief The lookup results will be used for redeclaration of a name,
2680      /// if an entity by that name already exists.
2681      ForRedeclaration
2682    };
2683  
2684    /// \brief The possible outcomes of name lookup for a literal operator.
2685    enum LiteralOperatorLookupResult {
2686      /// \brief The lookup resulted in an error.
2687      LOLR_Error,
2688      /// \brief The lookup found a single 'cooked' literal operator, which
2689      /// expects a normal literal to be built and passed to it.
2690      LOLR_Cooked,
2691      /// \brief The lookup found a single 'raw' literal operator, which expects
2692      /// a string literal containing the spelling of the literal token.
2693      LOLR_Raw,
2694      /// \brief The lookup found an overload set of literal operator templates,
2695      /// which expect the characters of the spelling of the literal token to be
2696      /// passed as a non-type template argument pack.
2697      LOLR_Template,
2698      /// \brief The lookup found an overload set of literal operator templates,
2699      /// which expect the character type and characters of the spelling of the
2700      /// string literal token to be passed as template arguments.
2701      LOLR_StringTemplate
2702    };
2703  
2704    SpecialMemberOverloadResult *LookupSpecialMember(CXXRecordDecl *D,
2705                                                     CXXSpecialMember SM,
2706                                                     bool ConstArg,
2707                                                     bool VolatileArg,
2708                                                     bool RValueThis,
2709                                                     bool ConstThis,
2710                                                     bool VolatileThis);
2711  
2712    typedef std::function<void(const TypoCorrection &)> TypoDiagnosticGenerator;
2713    typedef std::function<ExprResult(Sema &, TypoExpr *, TypoCorrection)>
2714        TypoRecoveryCallback;
2715  
2716  private:
2717    bool CppLookupName(LookupResult &R, Scope *S);
2718  
2719    struct TypoExprState {
2720      std::unique_ptr<TypoCorrectionConsumer> Consumer;
2721      TypoDiagnosticGenerator DiagHandler;
2722      TypoRecoveryCallback RecoveryHandler;
2723      TypoExprState();
2724      TypoExprState(TypoExprState&& other) LLVM_NOEXCEPT;
2725      TypoExprState& operator=(TypoExprState&& other) LLVM_NOEXCEPT;
2726    };
2727  
2728    /// \brief The set of unhandled TypoExprs and their associated state.
2729    llvm::MapVector<TypoExpr *, TypoExprState> DelayedTypos;
2730  
2731    /// \brief Creates a new TypoExpr AST node.
2732    TypoExpr *createDelayedTypo(std::unique_ptr<TypoCorrectionConsumer> TCC,
2733                                TypoDiagnosticGenerator TDG,
2734                                TypoRecoveryCallback TRC);
2735  
2736    // \brief The set of known/encountered (unique, canonicalized) NamespaceDecls.
2737    //
2738    // The boolean value will be true to indicate that the namespace was loaded
2739    // from an AST/PCH file, or false otherwise.
2740    llvm::MapVector<NamespaceDecl*, bool> KnownNamespaces;
2741  
2742    /// \brief Whether we have already loaded known namespaces from an extenal
2743    /// source.
2744    bool LoadedExternalKnownNamespaces;
2745  
2746    /// \brief Helper for CorrectTypo and CorrectTypoDelayed used to create and
2747    /// populate a new TypoCorrectionConsumer. Returns nullptr if typo correction
2748    /// should be skipped entirely.
2749    std::unique_ptr<TypoCorrectionConsumer>
2750    makeTypoCorrectionConsumer(const DeclarationNameInfo &Typo,
2751                               Sema::LookupNameKind LookupKind, Scope *S,
2752                               CXXScopeSpec *SS,
2753                               std::unique_ptr<CorrectionCandidateCallback> CCC,
2754                               DeclContext *MemberContext, bool EnteringContext,
2755                               const ObjCObjectPointerType *OPT,
2756                               bool ErrorRecovery);
2757  
2758  public:
2759    const TypoExprState &getTypoExprState(TypoExpr *TE) const;
2760  
2761    /// \brief Clears the state of the given TypoExpr.
2762    void clearDelayedTypo(TypoExpr *TE);
2763  
2764    /// \brief Look up a name, looking for a single declaration.  Return
2765    /// null if the results were absent, ambiguous, or overloaded.
2766    ///
2767    /// It is preferable to use the elaborated form and explicitly handle
2768    /// ambiguity and overloaded.
2769    NamedDecl *LookupSingleName(Scope *S, DeclarationName Name,
2770                                SourceLocation Loc,
2771                                LookupNameKind NameKind,
2772                                RedeclarationKind Redecl
2773                                  = NotForRedeclaration);
2774    bool LookupName(LookupResult &R, Scope *S,
2775                    bool AllowBuiltinCreation = false);
2776    bool LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx,
2777                             bool InUnqualifiedLookup = false);
2778    bool LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx,
2779                             CXXScopeSpec &SS);
2780    bool LookupParsedName(LookupResult &R, Scope *S, CXXScopeSpec *SS,
2781                          bool AllowBuiltinCreation = false,
2782                          bool EnteringContext = false);
2783    ObjCProtocolDecl *LookupProtocol(IdentifierInfo *II, SourceLocation IdLoc,
2784                                     RedeclarationKind Redecl
2785                                       = NotForRedeclaration);
2786    bool LookupInSuper(LookupResult &R, CXXRecordDecl *Class);
2787  
2788    void LookupOverloadedOperatorName(OverloadedOperatorKind Op, Scope *S,
2789                                      QualType T1, QualType T2,
2790                                      UnresolvedSetImpl &Functions);
2791    void addOverloadedOperatorToUnresolvedSet(UnresolvedSetImpl &Functions,
2792                                              DeclAccessPair Operator,
2793                                              QualType T1, QualType T2);
2794  
2795    LabelDecl *LookupOrCreateLabel(IdentifierInfo *II, SourceLocation IdentLoc,
2796                                   SourceLocation GnuLabelLoc = SourceLocation());
2797  
2798    DeclContextLookupResult LookupConstructors(CXXRecordDecl *Class);
2799    CXXConstructorDecl *LookupDefaultConstructor(CXXRecordDecl *Class);
2800    CXXConstructorDecl *LookupCopyingConstructor(CXXRecordDecl *Class,
2801                                                 unsigned Quals);
2802    CXXMethodDecl *LookupCopyingAssignment(CXXRecordDecl *Class, unsigned Quals,
2803                                           bool RValueThis, unsigned ThisQuals);
2804    CXXConstructorDecl *LookupMovingConstructor(CXXRecordDecl *Class,
2805                                                unsigned Quals);
2806    CXXMethodDecl *LookupMovingAssignment(CXXRecordDecl *Class, unsigned Quals,
2807                                          bool RValueThis, unsigned ThisQuals);
2808    CXXDestructorDecl *LookupDestructor(CXXRecordDecl *Class);
2809  
2810    bool checkLiteralOperatorId(const CXXScopeSpec &SS, const UnqualifiedId &Id);
2811    LiteralOperatorLookupResult LookupLiteralOperator(Scope *S, LookupResult &R,
2812                                                      ArrayRef<QualType> ArgTys,
2813                                                      bool AllowRaw,
2814                                                      bool AllowTemplate,
2815                                                      bool AllowStringTemplate);
2816    bool isKnownName(StringRef name);
2817  
2818    void ArgumentDependentLookup(DeclarationName Name, SourceLocation Loc,
2819                                 ArrayRef<Expr *> Args, ADLResult &Functions);
2820  
2821    void LookupVisibleDecls(Scope *S, LookupNameKind Kind,
2822                            VisibleDeclConsumer &Consumer,
2823                            bool IncludeGlobalScope = true);
2824    void LookupVisibleDecls(DeclContext *Ctx, LookupNameKind Kind,
2825                            VisibleDeclConsumer &Consumer,
2826                            bool IncludeGlobalScope = true);
2827  
2828    enum CorrectTypoKind {
2829      CTK_NonError,     // CorrectTypo used in a non error recovery situation.
2830      CTK_ErrorRecovery // CorrectTypo used in normal error recovery.
2831    };
2832  
2833    TypoCorrection CorrectTypo(const DeclarationNameInfo &Typo,
2834                               Sema::LookupNameKind LookupKind,
2835                               Scope *S, CXXScopeSpec *SS,
2836                               std::unique_ptr<CorrectionCandidateCallback> CCC,
2837                               CorrectTypoKind Mode,
2838                               DeclContext *MemberContext = nullptr,
2839                               bool EnteringContext = false,
2840                               const ObjCObjectPointerType *OPT = nullptr,
2841                               bool RecordFailure = true);
2842  
2843    TypoExpr *CorrectTypoDelayed(const DeclarationNameInfo &Typo,
2844                                 Sema::LookupNameKind LookupKind, Scope *S,
2845                                 CXXScopeSpec *SS,
2846                                 std::unique_ptr<CorrectionCandidateCallback> CCC,
2847                                 TypoDiagnosticGenerator TDG,
2848                                 TypoRecoveryCallback TRC, CorrectTypoKind Mode,
2849                                 DeclContext *MemberContext = nullptr,
2850                                 bool EnteringContext = false,
2851                                 const ObjCObjectPointerType *OPT = nullptr);
2852  
2853    /// \brief Process any TypoExprs in the given Expr and its children,
2854    /// generating diagnostics as appropriate and returning a new Expr if there
2855    /// were typos that were all successfully corrected and ExprError if one or
2856    /// more typos could not be corrected.
2857    ///
2858    /// \param E The Expr to check for TypoExprs.
2859    ///
2860    /// \param InitDecl A VarDecl to avoid because the Expr being corrected is its
2861    /// initializer.
2862    ///
2863    /// \param Filter A function applied to a newly rebuilt Expr to determine if
2864    /// it is an acceptable/usable result from a single combination of typo
2865    /// corrections. As long as the filter returns ExprError, different
2866    /// combinations of corrections will be tried until all are exhausted.
2867    ExprResult
2868    CorrectDelayedTyposInExpr(Expr *E, VarDecl *InitDecl = nullptr,
2869                              llvm::function_ref<ExprResult(Expr *)> Filter =
2870                                  [](Expr *E) -> ExprResult { return E; });
2871  
2872    ExprResult
CorrectDelayedTyposInExpr(Expr * E,llvm::function_ref<ExprResult (Expr *)> Filter)2873    CorrectDelayedTyposInExpr(Expr *E,
2874                              llvm::function_ref<ExprResult(Expr *)> Filter) {
2875      return CorrectDelayedTyposInExpr(E, nullptr, Filter);
2876    }
2877  
2878    ExprResult
2879    CorrectDelayedTyposInExpr(ExprResult ER, VarDecl *InitDecl = nullptr,
2880                              llvm::function_ref<ExprResult(Expr *)> Filter =
2881                                  [](Expr *E) -> ExprResult { return E; }) {
2882      return ER.isInvalid() ? ER : CorrectDelayedTyposInExpr(ER.get(), Filter);
2883    }
2884  
2885    ExprResult
CorrectDelayedTyposInExpr(ExprResult ER,llvm::function_ref<ExprResult (Expr *)> Filter)2886    CorrectDelayedTyposInExpr(ExprResult ER,
2887                              llvm::function_ref<ExprResult(Expr *)> Filter) {
2888      return CorrectDelayedTyposInExpr(ER, nullptr, Filter);
2889    }
2890  
2891    void diagnoseTypo(const TypoCorrection &Correction,
2892                      const PartialDiagnostic &TypoDiag,
2893                      bool ErrorRecovery = true);
2894  
2895    void diagnoseTypo(const TypoCorrection &Correction,
2896                      const PartialDiagnostic &TypoDiag,
2897                      const PartialDiagnostic &PrevNote,
2898                      bool ErrorRecovery = true);
2899  
2900    void FindAssociatedClassesAndNamespaces(SourceLocation InstantiationLoc,
2901                                            ArrayRef<Expr *> Args,
2902                                     AssociatedNamespaceSet &AssociatedNamespaces,
2903                                     AssociatedClassSet &AssociatedClasses);
2904  
2905    void FilterLookupForScope(LookupResult &R, DeclContext *Ctx, Scope *S,
2906                              bool ConsiderLinkage, bool AllowInlineNamespace);
2907  
2908    void DiagnoseAmbiguousLookup(LookupResult &Result);
2909    //@}
2910  
2911    ObjCInterfaceDecl *getObjCInterfaceDecl(IdentifierInfo *&Id,
2912                                            SourceLocation IdLoc,
2913                                            bool TypoCorrection = false);
2914    NamedDecl *LazilyCreateBuiltin(IdentifierInfo *II, unsigned ID,
2915                                   Scope *S, bool ForRedeclaration,
2916                                   SourceLocation Loc);
2917    NamedDecl *ImplicitlyDefineFunction(SourceLocation Loc, IdentifierInfo &II,
2918                                        Scope *S);
2919    void AddKnownFunctionAttributes(FunctionDecl *FD);
2920  
2921    // More parsing and symbol table subroutines.
2922  
2923    void ProcessPragmaWeak(Scope *S, Decl *D);
2924    // Decl attributes - this routine is the top level dispatcher.
2925    void ProcessDeclAttributes(Scope *S, Decl *D, const Declarator &PD);
2926    void ProcessDeclAttributeList(Scope *S, Decl *D, const AttributeList *AL,
2927                                  bool IncludeCXX11Attributes = true);
2928    bool ProcessAccessDeclAttributeList(AccessSpecDecl *ASDecl,
2929                                        const AttributeList *AttrList);
2930  
2931    void checkUnusedDeclAttributes(Declarator &D);
2932  
2933    /// Determine if type T is a valid subject for a nonnull and similar
2934    /// attributes. By default, we look through references (the behavior used by
2935    /// nonnull), but if the second parameter is true, then we treat a reference
2936    /// type as valid.
2937    bool isValidPointerAttrType(QualType T, bool RefOkay = false);
2938  
2939    bool CheckRegparmAttr(const AttributeList &attr, unsigned &value);
2940    bool CheckCallingConvAttr(const AttributeList &attr, CallingConv &CC,
2941                              const FunctionDecl *FD = nullptr);
2942    bool CheckNoReturnAttr(const AttributeList &attr);
2943    bool checkStringLiteralArgumentAttr(const AttributeList &Attr,
2944                                        unsigned ArgNum, StringRef &Str,
2945                                        SourceLocation *ArgLocation = nullptr);
2946    bool checkSectionName(SourceLocation LiteralLoc, StringRef Str);
2947    void checkTargetAttr(SourceLocation LiteralLoc, StringRef Str);
2948    bool checkMSInheritanceAttrOnDefinition(
2949        CXXRecordDecl *RD, SourceRange Range, bool BestCase,
2950        MSInheritanceAttr::Spelling SemanticSpelling);
2951  
2952    void CheckAlignasUnderalignment(Decl *D);
2953  
2954    /// Adjust the calling convention of a method to be the ABI default if it
2955    /// wasn't specified explicitly.  This handles method types formed from
2956    /// function type typedefs and typename template arguments.
2957    void adjustMemberFunctionCC(QualType &T, bool IsStatic, bool IsCtorOrDtor,
2958                                SourceLocation Loc);
2959  
2960    // Check if there is an explicit attribute, but only look through parens.
2961    // The intent is to look for an attribute on the current declarator, but not
2962    // one that came from a typedef.
2963    bool hasExplicitCallingConv(QualType &T);
2964  
2965    /// Get the outermost AttributedType node that sets a calling convention.
2966    /// Valid types should not have multiple attributes with different CCs.
2967    const AttributedType *getCallingConvAttributedType(QualType T) const;
2968  
2969    /// Check whether a nullability type specifier can be added to the given
2970    /// type.
2971    ///
2972    /// \param type The type to which the nullability specifier will be
2973    /// added. On success, this type will be updated appropriately.
2974    ///
2975    /// \param nullability The nullability specifier to add.
2976    ///
2977    /// \param nullabilityLoc The location of the nullability specifier.
2978    ///
2979    /// \param isContextSensitive Whether this nullability specifier was
2980    /// written as a context-sensitive keyword (in an Objective-C
2981    /// method) or an Objective-C property attribute, rather than as an
2982    /// underscored type specifier.
2983    ///
2984    /// \returns true if nullability cannot be applied, false otherwise.
2985    bool checkNullabilityTypeSpecifier(QualType &type, NullabilityKind nullability,
2986                                       SourceLocation nullabilityLoc,
2987                                       bool isContextSensitive);
2988  
2989    /// \brief Stmt attributes - this routine is the top level dispatcher.
2990    StmtResult ProcessStmtAttributes(Stmt *Stmt, AttributeList *Attrs,
2991                                     SourceRange Range);
2992  
2993    void WarnConflictingTypedMethods(ObjCMethodDecl *Method,
2994                                     ObjCMethodDecl *MethodDecl,
2995                                     bool IsProtocolMethodDecl);
2996  
2997    void CheckConflictingOverridingMethod(ObjCMethodDecl *Method,
2998                                     ObjCMethodDecl *Overridden,
2999                                     bool IsProtocolMethodDecl);
3000  
3001    /// WarnExactTypedMethods - This routine issues a warning if method
3002    /// implementation declaration matches exactly that of its declaration.
3003    void WarnExactTypedMethods(ObjCMethodDecl *Method,
3004                               ObjCMethodDecl *MethodDecl,
3005                               bool IsProtocolMethodDecl);
3006  
3007    typedef llvm::SmallPtrSet<Selector, 8> SelectorSet;
3008    typedef llvm::DenseMap<Selector, ObjCMethodDecl*> ProtocolsMethodsMap;
3009  
3010    /// CheckImplementationIvars - This routine checks if the instance variables
3011    /// listed in the implelementation match those listed in the interface.
3012    void CheckImplementationIvars(ObjCImplementationDecl *ImpDecl,
3013                                  ObjCIvarDecl **Fields, unsigned nIvars,
3014                                  SourceLocation Loc);
3015  
3016    /// ImplMethodsVsClassMethods - This is main routine to warn if any method
3017    /// remains unimplemented in the class or category \@implementation.
3018    void ImplMethodsVsClassMethods(Scope *S, ObjCImplDecl* IMPDecl,
3019                                   ObjCContainerDecl* IDecl,
3020                                   bool IncompleteImpl = false);
3021  
3022    /// DiagnoseUnimplementedProperties - This routine warns on those properties
3023    /// which must be implemented by this implementation.
3024    void DiagnoseUnimplementedProperties(Scope *S, ObjCImplDecl* IMPDecl,
3025                                         ObjCContainerDecl *CDecl,
3026                                         bool SynthesizeProperties);
3027  
3028    /// Diagnose any null-resettable synthesized setters.
3029    void diagnoseNullResettableSynthesizedSetters(const ObjCImplDecl *impDecl);
3030  
3031    /// DefaultSynthesizeProperties - This routine default synthesizes all
3032    /// properties which must be synthesized in the class's \@implementation.
3033    void DefaultSynthesizeProperties (Scope *S, ObjCImplDecl* IMPDecl,
3034                                      ObjCInterfaceDecl *IDecl);
3035    void DefaultSynthesizeProperties(Scope *S, Decl *D);
3036  
3037    /// IvarBacksCurrentMethodAccessor - This routine returns 'true' if 'IV' is
3038    /// an ivar synthesized for 'Method' and 'Method' is a property accessor
3039    /// declared in class 'IFace'.
3040    bool IvarBacksCurrentMethodAccessor(ObjCInterfaceDecl *IFace,
3041                                        ObjCMethodDecl *Method, ObjCIvarDecl *IV);
3042  
3043    /// DiagnoseUnusedBackingIvarInAccessor - Issue an 'unused' warning if ivar which
3044    /// backs the property is not used in the property's accessor.
3045    void DiagnoseUnusedBackingIvarInAccessor(Scope *S,
3046                                             const ObjCImplementationDecl *ImplD);
3047  
3048    /// GetIvarBackingPropertyAccessor - If method is a property setter/getter and
3049    /// it property has a backing ivar, returns this ivar; otherwise, returns NULL.
3050    /// It also returns ivar's property on success.
3051    ObjCIvarDecl *GetIvarBackingPropertyAccessor(const ObjCMethodDecl *Method,
3052                                                 const ObjCPropertyDecl *&PDecl) const;
3053  
3054    /// Called by ActOnProperty to handle \@property declarations in
3055    /// class extensions.
3056    ObjCPropertyDecl *HandlePropertyInClassExtension(Scope *S,
3057                        SourceLocation AtLoc,
3058                        SourceLocation LParenLoc,
3059                        FieldDeclarator &FD,
3060                        Selector GetterSel,
3061                        Selector SetterSel,
3062                        const bool isReadWrite,
3063                        unsigned &Attributes,
3064                        const unsigned AttributesAsWritten,
3065                        QualType T,
3066                        TypeSourceInfo *TSI,
3067                        tok::ObjCKeywordKind MethodImplKind);
3068  
3069    /// Called by ActOnProperty and HandlePropertyInClassExtension to
3070    /// handle creating the ObjcPropertyDecl for a category or \@interface.
3071    ObjCPropertyDecl *CreatePropertyDecl(Scope *S,
3072                                         ObjCContainerDecl *CDecl,
3073                                         SourceLocation AtLoc,
3074                                         SourceLocation LParenLoc,
3075                                         FieldDeclarator &FD,
3076                                         Selector GetterSel,
3077                                         Selector SetterSel,
3078                                         const bool isReadWrite,
3079                                         const unsigned Attributes,
3080                                         const unsigned AttributesAsWritten,
3081                                         QualType T,
3082                                         TypeSourceInfo *TSI,
3083                                         tok::ObjCKeywordKind MethodImplKind,
3084                                         DeclContext *lexicalDC = nullptr);
3085  
3086    /// AtomicPropertySetterGetterRules - This routine enforces the rule (via
3087    /// warning) when atomic property has one but not the other user-declared
3088    /// setter or getter.
3089    void AtomicPropertySetterGetterRules(ObjCImplDecl* IMPDecl,
3090                                         ObjCInterfaceDecl* IDecl);
3091  
3092    void DiagnoseOwningPropertyGetterSynthesis(const ObjCImplementationDecl *D);
3093  
3094    void DiagnoseMissingDesignatedInitOverrides(
3095                                            const ObjCImplementationDecl *ImplD,
3096                                            const ObjCInterfaceDecl *IFD);
3097  
3098    void DiagnoseDuplicateIvars(ObjCInterfaceDecl *ID, ObjCInterfaceDecl *SID);
3099  
3100    enum MethodMatchStrategy {
3101      MMS_loose,
3102      MMS_strict
3103    };
3104  
3105    /// MatchTwoMethodDeclarations - Checks if two methods' type match and returns
3106    /// true, or false, accordingly.
3107    bool MatchTwoMethodDeclarations(const ObjCMethodDecl *Method,
3108                                    const ObjCMethodDecl *PrevMethod,
3109                                    MethodMatchStrategy strategy = MMS_strict);
3110  
3111    /// MatchAllMethodDeclarations - Check methods declaraed in interface or
3112    /// or protocol against those declared in their implementations.
3113    void MatchAllMethodDeclarations(const SelectorSet &InsMap,
3114                                    const SelectorSet &ClsMap,
3115                                    SelectorSet &InsMapSeen,
3116                                    SelectorSet &ClsMapSeen,
3117                                    ObjCImplDecl* IMPDecl,
3118                                    ObjCContainerDecl* IDecl,
3119                                    bool &IncompleteImpl,
3120                                    bool ImmediateClass,
3121                                    bool WarnCategoryMethodImpl=false);
3122  
3123    /// CheckCategoryVsClassMethodMatches - Checks that methods implemented in
3124    /// category matches with those implemented in its primary class and
3125    /// warns each time an exact match is found.
3126    void CheckCategoryVsClassMethodMatches(ObjCCategoryImplDecl *CatIMP);
3127  
3128    /// \brief Add the given method to the list of globally-known methods.
3129    void addMethodToGlobalList(ObjCMethodList *List, ObjCMethodDecl *Method);
3130  
3131  private:
3132    /// AddMethodToGlobalPool - Add an instance or factory method to the global
3133    /// pool. See descriptoin of AddInstanceMethodToGlobalPool.
3134    void AddMethodToGlobalPool(ObjCMethodDecl *Method, bool impl, bool instance);
3135  
3136    /// LookupMethodInGlobalPool - Returns the instance or factory method and
3137    /// optionally warns if there are multiple signatures.
3138    ObjCMethodDecl *LookupMethodInGlobalPool(Selector Sel, SourceRange R,
3139                                             bool receiverIdOrClass,
3140                                             bool instance);
3141  
3142  public:
3143    /// \brief - Returns instance or factory methods in global method pool for
3144    /// given selector. If no such method or only one method found, function returns
3145    /// false; otherwise, it returns true
3146    bool CollectMultipleMethodsInGlobalPool(Selector Sel,
3147                                            SmallVectorImpl<ObjCMethodDecl*>& Methods,
3148                                            bool instance);
3149  
3150    bool AreMultipleMethodsInGlobalPool(Selector Sel, ObjCMethodDecl *BestMethod,
3151                                        SourceRange R,
3152                                        bool receiverIdOrClass);
3153  
3154    void DiagnoseMultipleMethodInGlobalPool(SmallVectorImpl<ObjCMethodDecl*> &Methods,
3155                                            Selector Sel, SourceRange R,
3156                                            bool receiverIdOrClass);
3157  
3158  private:
3159    /// \brief - Returns a selector which best matches given argument list or
3160    /// nullptr if none could be found
3161    ObjCMethodDecl *SelectBestMethod(Selector Sel, MultiExprArg Args,
3162                                     bool IsInstance);
3163  
3164  
3165    /// \brief Record the typo correction failure and return an empty correction.
3166    TypoCorrection FailedCorrection(IdentifierInfo *Typo, SourceLocation TypoLoc,
3167                                    bool RecordFailure = true) {
3168      if (RecordFailure)
3169        TypoCorrectionFailures[Typo].insert(TypoLoc);
3170      return TypoCorrection();
3171    }
3172  
3173  public:
3174    /// AddInstanceMethodToGlobalPool - All instance methods in a translation
3175    /// unit are added to a global pool. This allows us to efficiently associate
3176    /// a selector with a method declaraation for purposes of typechecking
3177    /// messages sent to "id" (where the class of the object is unknown).
3178    void AddInstanceMethodToGlobalPool(ObjCMethodDecl *Method, bool impl=false) {
3179      AddMethodToGlobalPool(Method, impl, /*instance*/true);
3180    }
3181  
3182    /// AddFactoryMethodToGlobalPool - Same as above, but for factory methods.
3183    void AddFactoryMethodToGlobalPool(ObjCMethodDecl *Method, bool impl=false) {
3184      AddMethodToGlobalPool(Method, impl, /*instance*/false);
3185    }
3186  
3187    /// AddAnyMethodToGlobalPool - Add any method, instance or factory to global
3188    /// pool.
3189    void AddAnyMethodToGlobalPool(Decl *D);
3190  
3191    /// LookupInstanceMethodInGlobalPool - Returns the method and warns if
3192    /// there are multiple signatures.
3193    ObjCMethodDecl *LookupInstanceMethodInGlobalPool(Selector Sel, SourceRange R,
3194                                                     bool receiverIdOrClass=false) {
3195      return LookupMethodInGlobalPool(Sel, R, receiverIdOrClass,
3196                                      /*instance*/true);
3197    }
3198  
3199    /// LookupFactoryMethodInGlobalPool - Returns the method and warns if
3200    /// there are multiple signatures.
3201    ObjCMethodDecl *LookupFactoryMethodInGlobalPool(Selector Sel, SourceRange R,
3202                                                    bool receiverIdOrClass=false) {
3203      return LookupMethodInGlobalPool(Sel, R, receiverIdOrClass,
3204                                      /*instance*/false);
3205    }
3206  
3207    const ObjCMethodDecl *SelectorsForTypoCorrection(Selector Sel,
3208                                QualType ObjectType=QualType());
3209    /// LookupImplementedMethodInGlobalPool - Returns the method which has an
3210    /// implementation.
3211    ObjCMethodDecl *LookupImplementedMethodInGlobalPool(Selector Sel);
3212  
3213    /// CollectIvarsToConstructOrDestruct - Collect those ivars which require
3214    /// initialization.
3215    void CollectIvarsToConstructOrDestruct(ObjCInterfaceDecl *OI,
3216                                    SmallVectorImpl<ObjCIvarDecl*> &Ivars);
3217  
3218    //===--------------------------------------------------------------------===//
3219    // Statement Parsing Callbacks: SemaStmt.cpp.
3220  public:
3221    class FullExprArg {
3222    public:
FullExprArg(Sema & actions)3223      FullExprArg(Sema &actions) : E(nullptr) { }
3224  
release()3225      ExprResult release() {
3226        return E;
3227      }
3228  
get()3229      Expr *get() const { return E; }
3230  
3231      Expr *operator->() {
3232        return E;
3233      }
3234  
3235    private:
3236      // FIXME: No need to make the entire Sema class a friend when it's just
3237      // Sema::MakeFullExpr that needs access to the constructor below.
3238      friend class Sema;
3239  
FullExprArg(Expr * expr)3240      explicit FullExprArg(Expr *expr) : E(expr) {}
3241  
3242      Expr *E;
3243    };
3244  
MakeFullExpr(Expr * Arg)3245    FullExprArg MakeFullExpr(Expr *Arg) {
3246      return MakeFullExpr(Arg, Arg ? Arg->getExprLoc() : SourceLocation());
3247    }
MakeFullExpr(Expr * Arg,SourceLocation CC)3248    FullExprArg MakeFullExpr(Expr *Arg, SourceLocation CC) {
3249      return FullExprArg(ActOnFinishFullExpr(Arg, CC).get());
3250    }
MakeFullDiscardedValueExpr(Expr * Arg)3251    FullExprArg MakeFullDiscardedValueExpr(Expr *Arg) {
3252      ExprResult FE =
3253        ActOnFinishFullExpr(Arg, Arg ? Arg->getExprLoc() : SourceLocation(),
3254                            /*DiscardedValue*/ true);
3255      return FullExprArg(FE.get());
3256    }
3257  
3258    StmtResult ActOnExprStmt(ExprResult Arg);
3259    StmtResult ActOnExprStmtError();
3260  
3261    StmtResult ActOnNullStmt(SourceLocation SemiLoc,
3262                             bool HasLeadingEmptyMacro = false);
3263  
3264    void ActOnStartOfCompoundStmt();
3265    void ActOnFinishOfCompoundStmt();
3266    StmtResult ActOnCompoundStmt(SourceLocation L, SourceLocation R,
3267                                 ArrayRef<Stmt *> Elts, bool isStmtExpr);
3268  
3269    /// \brief A RAII object to enter scope of a compound statement.
3270    class CompoundScopeRAII {
3271    public:
CompoundScopeRAII(Sema & S)3272      CompoundScopeRAII(Sema &S): S(S) {
3273        S.ActOnStartOfCompoundStmt();
3274      }
3275  
~CompoundScopeRAII()3276      ~CompoundScopeRAII() {
3277        S.ActOnFinishOfCompoundStmt();
3278      }
3279  
3280    private:
3281      Sema &S;
3282    };
3283  
3284    /// An RAII helper that pops function a function scope on exit.
3285    struct FunctionScopeRAII {
3286      Sema &S;
3287      bool Active;
FunctionScopeRAIIFunctionScopeRAII3288      FunctionScopeRAII(Sema &S) : S(S), Active(true) {}
~FunctionScopeRAIIFunctionScopeRAII3289      ~FunctionScopeRAII() {
3290        if (Active)
3291          S.PopFunctionScopeInfo();
3292      }
disableFunctionScopeRAII3293      void disable() { Active = false; }
3294    };
3295  
3296    StmtResult ActOnDeclStmt(DeclGroupPtrTy Decl,
3297                                     SourceLocation StartLoc,
3298                                     SourceLocation EndLoc);
3299    void ActOnForEachDeclStmt(DeclGroupPtrTy Decl);
3300    StmtResult ActOnForEachLValueExpr(Expr *E);
3301    StmtResult ActOnCaseStmt(SourceLocation CaseLoc, Expr *LHSVal,
3302                                     SourceLocation DotDotDotLoc, Expr *RHSVal,
3303                                     SourceLocation ColonLoc);
3304    void ActOnCaseStmtBody(Stmt *CaseStmt, Stmt *SubStmt);
3305  
3306    StmtResult ActOnDefaultStmt(SourceLocation DefaultLoc,
3307                                        SourceLocation ColonLoc,
3308                                        Stmt *SubStmt, Scope *CurScope);
3309    StmtResult ActOnLabelStmt(SourceLocation IdentLoc, LabelDecl *TheDecl,
3310                              SourceLocation ColonLoc, Stmt *SubStmt);
3311  
3312    StmtResult ActOnAttributedStmt(SourceLocation AttrLoc,
3313                                   ArrayRef<const Attr*> Attrs,
3314                                   Stmt *SubStmt);
3315  
3316    StmtResult ActOnIfStmt(SourceLocation IfLoc,
3317                           FullExprArg CondVal, Decl *CondVar,
3318                           Stmt *ThenVal,
3319                           SourceLocation ElseLoc, Stmt *ElseVal);
3320    StmtResult ActOnStartOfSwitchStmt(SourceLocation SwitchLoc,
3321                                              Expr *Cond,
3322                                              Decl *CondVar);
3323    StmtResult ActOnFinishSwitchStmt(SourceLocation SwitchLoc,
3324                                             Stmt *Switch, Stmt *Body);
3325    StmtResult ActOnWhileStmt(SourceLocation WhileLoc,
3326                              FullExprArg Cond,
3327                              Decl *CondVar, Stmt *Body);
3328    StmtResult ActOnDoStmt(SourceLocation DoLoc, Stmt *Body,
3329                                   SourceLocation WhileLoc,
3330                                   SourceLocation CondLParen, Expr *Cond,
3331                                   SourceLocation CondRParen);
3332  
3333    StmtResult ActOnForStmt(SourceLocation ForLoc,
3334                            SourceLocation LParenLoc,
3335                            Stmt *First, FullExprArg Second,
3336                            Decl *SecondVar,
3337                            FullExprArg Third,
3338                            SourceLocation RParenLoc,
3339                            Stmt *Body);
3340    ExprResult CheckObjCForCollectionOperand(SourceLocation forLoc,
3341                                             Expr *collection);
3342    StmtResult ActOnObjCForCollectionStmt(SourceLocation ForColLoc,
3343                                          Stmt *First, Expr *collection,
3344                                          SourceLocation RParenLoc);
3345    StmtResult FinishObjCForCollectionStmt(Stmt *ForCollection, Stmt *Body);
3346  
3347    enum BuildForRangeKind {
3348      /// Initial building of a for-range statement.
3349      BFRK_Build,
3350      /// Instantiation or recovery rebuild of a for-range statement. Don't
3351      /// attempt any typo-correction.
3352      BFRK_Rebuild,
3353      /// Determining whether a for-range statement could be built. Avoid any
3354      /// unnecessary or irreversible actions.
3355      BFRK_Check
3356    };
3357  
3358    StmtResult ActOnCXXForRangeStmt(Scope *S, SourceLocation ForLoc,
3359                                    SourceLocation CoawaitLoc,
3360                                    Stmt *LoopVar,
3361                                    SourceLocation ColonLoc, Expr *Collection,
3362                                    SourceLocation RParenLoc,
3363                                    BuildForRangeKind Kind);
3364    StmtResult BuildCXXForRangeStmt(SourceLocation ForLoc,
3365                                    SourceLocation CoawaitLoc,
3366                                    SourceLocation ColonLoc,
3367                                    Stmt *RangeDecl, Stmt *BeginEndDecl,
3368                                    Expr *Cond, Expr *Inc,
3369                                    Stmt *LoopVarDecl,
3370                                    SourceLocation RParenLoc,
3371                                    BuildForRangeKind Kind);
3372    StmtResult FinishCXXForRangeStmt(Stmt *ForRange, Stmt *Body);
3373  
3374    StmtResult ActOnGotoStmt(SourceLocation GotoLoc,
3375                             SourceLocation LabelLoc,
3376                             LabelDecl *TheDecl);
3377    StmtResult ActOnIndirectGotoStmt(SourceLocation GotoLoc,
3378                                     SourceLocation StarLoc,
3379                                     Expr *DestExp);
3380    StmtResult ActOnContinueStmt(SourceLocation ContinueLoc, Scope *CurScope);
3381    StmtResult ActOnBreakStmt(SourceLocation BreakLoc, Scope *CurScope);
3382  
3383    void ActOnCapturedRegionStart(SourceLocation Loc, Scope *CurScope,
3384                                  CapturedRegionKind Kind, unsigned NumParams);
3385    typedef std::pair<StringRef, QualType> CapturedParamNameType;
3386    void ActOnCapturedRegionStart(SourceLocation Loc, Scope *CurScope,
3387                                  CapturedRegionKind Kind,
3388                                  ArrayRef<CapturedParamNameType> Params);
3389    StmtResult ActOnCapturedRegionEnd(Stmt *S);
3390    void ActOnCapturedRegionError();
3391    RecordDecl *CreateCapturedStmtRecordDecl(CapturedDecl *&CD,
3392                                             SourceLocation Loc,
3393                                             unsigned NumParams);
3394    VarDecl *getCopyElisionCandidate(QualType ReturnType, Expr *E,
3395                                     bool AllowFunctionParameters);
3396    bool isCopyElisionCandidate(QualType ReturnType, const VarDecl *VD,
3397                                bool AllowFunctionParameters);
3398  
3399    StmtResult ActOnReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp,
3400                               Scope *CurScope);
3401    StmtResult BuildReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp);
3402    StmtResult ActOnCapScopeReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp);
3403  
3404    StmtResult ActOnGCCAsmStmt(SourceLocation AsmLoc, bool IsSimple,
3405                               bool IsVolatile, unsigned NumOutputs,
3406                               unsigned NumInputs, IdentifierInfo **Names,
3407                               MultiExprArg Constraints, MultiExprArg Exprs,
3408                               Expr *AsmString, MultiExprArg Clobbers,
3409                               SourceLocation RParenLoc);
3410  
3411    ExprResult LookupInlineAsmIdentifier(CXXScopeSpec &SS,
3412                                         SourceLocation TemplateKWLoc,
3413                                         UnqualifiedId &Id,
3414                                         llvm::InlineAsmIdentifierInfo &Info,
3415                                         bool IsUnevaluatedContext);
3416    bool LookupInlineAsmField(StringRef Base, StringRef Member,
3417                              unsigned &Offset, SourceLocation AsmLoc);
3418    ExprResult LookupInlineAsmVarDeclField(Expr *RefExpr, StringRef Member,
3419                                           unsigned &Offset,
3420                                           llvm::InlineAsmIdentifierInfo &Info,
3421                                           SourceLocation AsmLoc);
3422    StmtResult ActOnMSAsmStmt(SourceLocation AsmLoc, SourceLocation LBraceLoc,
3423                              ArrayRef<Token> AsmToks,
3424                              StringRef AsmString,
3425                              unsigned NumOutputs, unsigned NumInputs,
3426                              ArrayRef<StringRef> Constraints,
3427                              ArrayRef<StringRef> Clobbers,
3428                              ArrayRef<Expr*> Exprs,
3429                              SourceLocation EndLoc);
3430    LabelDecl *GetOrCreateMSAsmLabel(StringRef ExternalLabelName,
3431                                     SourceLocation Location,
3432                                     bool AlwaysCreate);
3433  
3434    VarDecl *BuildObjCExceptionDecl(TypeSourceInfo *TInfo, QualType ExceptionType,
3435                                    SourceLocation StartLoc,
3436                                    SourceLocation IdLoc, IdentifierInfo *Id,
3437                                    bool Invalid = false);
3438  
3439    Decl *ActOnObjCExceptionDecl(Scope *S, Declarator &D);
3440  
3441    StmtResult ActOnObjCAtCatchStmt(SourceLocation AtLoc, SourceLocation RParen,
3442                                    Decl *Parm, Stmt *Body);
3443  
3444    StmtResult ActOnObjCAtFinallyStmt(SourceLocation AtLoc, Stmt *Body);
3445  
3446    StmtResult ActOnObjCAtTryStmt(SourceLocation AtLoc, Stmt *Try,
3447                                  MultiStmtArg Catch, Stmt *Finally);
3448  
3449    StmtResult BuildObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw);
3450    StmtResult ActOnObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw,
3451                                    Scope *CurScope);
3452    ExprResult ActOnObjCAtSynchronizedOperand(SourceLocation atLoc,
3453                                              Expr *operand);
3454    StmtResult ActOnObjCAtSynchronizedStmt(SourceLocation AtLoc,
3455                                           Expr *SynchExpr,
3456                                           Stmt *SynchBody);
3457  
3458    StmtResult ActOnObjCAutoreleasePoolStmt(SourceLocation AtLoc, Stmt *Body);
3459  
3460    VarDecl *BuildExceptionDeclaration(Scope *S, TypeSourceInfo *TInfo,
3461                                       SourceLocation StartLoc,
3462                                       SourceLocation IdLoc,
3463                                       IdentifierInfo *Id);
3464  
3465    Decl *ActOnExceptionDeclarator(Scope *S, Declarator &D);
3466  
3467    StmtResult ActOnCXXCatchBlock(SourceLocation CatchLoc,
3468                                  Decl *ExDecl, Stmt *HandlerBlock);
3469    StmtResult ActOnCXXTryBlock(SourceLocation TryLoc, Stmt *TryBlock,
3470                                ArrayRef<Stmt *> Handlers);
3471  
3472    StmtResult ActOnSEHTryBlock(bool IsCXXTry, // try (true) or __try (false) ?
3473                                SourceLocation TryLoc, Stmt *TryBlock,
3474                                Stmt *Handler);
3475    StmtResult ActOnSEHExceptBlock(SourceLocation Loc,
3476                                   Expr *FilterExpr,
3477                                   Stmt *Block);
3478    void ActOnStartSEHFinallyBlock();
3479    void ActOnAbortSEHFinallyBlock();
3480    StmtResult ActOnFinishSEHFinallyBlock(SourceLocation Loc, Stmt *Block);
3481    StmtResult ActOnSEHLeaveStmt(SourceLocation Loc, Scope *CurScope);
3482  
3483    void DiagnoseReturnInConstructorExceptionHandler(CXXTryStmt *TryBlock);
3484  
3485    bool ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const;
3486  
3487    /// \brief If it's a file scoped decl that must warn if not used, keep track
3488    /// of it.
3489    void MarkUnusedFileScopedDecl(const DeclaratorDecl *D);
3490  
3491    /// DiagnoseUnusedExprResult - If the statement passed in is an expression
3492    /// whose result is unused, warn.
3493    void DiagnoseUnusedExprResult(const Stmt *S);
3494    void DiagnoseUnusedNestedTypedefs(const RecordDecl *D);
3495    void DiagnoseUnusedDecl(const NamedDecl *ND);
3496  
3497    /// Emit \p DiagID if statement located on \p StmtLoc has a suspicious null
3498    /// statement as a \p Body, and it is located on the same line.
3499    ///
3500    /// This helps prevent bugs due to typos, such as:
3501    ///     if (condition);
3502    ///       do_stuff();
3503    void DiagnoseEmptyStmtBody(SourceLocation StmtLoc,
3504                               const Stmt *Body,
3505                               unsigned DiagID);
3506  
3507    /// Warn if a for/while loop statement \p S, which is followed by
3508    /// \p PossibleBody, has a suspicious null statement as a body.
3509    void DiagnoseEmptyLoopBody(const Stmt *S,
3510                               const Stmt *PossibleBody);
3511  
3512    /// Warn if a value is moved to itself.
3513    void DiagnoseSelfMove(const Expr *LHSExpr, const Expr *RHSExpr,
3514                          SourceLocation OpLoc);
3515  
3516    /// \brief Warn if we're implicitly casting from a _Nullable pointer type to a
3517    /// _Nonnull one.
3518    void diagnoseNullableToNonnullConversion(QualType DstType, QualType SrcType,
3519                                             SourceLocation Loc);
3520  
PushParsingDeclaration(sema::DelayedDiagnosticPool & pool)3521    ParsingDeclState PushParsingDeclaration(sema::DelayedDiagnosticPool &pool) {
3522      return DelayedDiagnostics.push(pool);
3523    }
3524    void PopParsingDeclaration(ParsingDeclState state, Decl *decl);
3525  
3526    typedef ProcessingContextState ParsingClassState;
PushParsingClass()3527    ParsingClassState PushParsingClass() {
3528      return DelayedDiagnostics.pushUndelayed();
3529    }
PopParsingClass(ParsingClassState state)3530    void PopParsingClass(ParsingClassState state) {
3531      DelayedDiagnostics.popUndelayed(state);
3532    }
3533  
3534    void redelayDiagnostics(sema::DelayedDiagnosticPool &pool);
3535  
3536    enum AvailabilityDiagnostic { AD_Deprecation, AD_Unavailable, AD_Partial };
3537  
3538    void EmitAvailabilityWarning(AvailabilityDiagnostic AD,
3539                                 NamedDecl *D, StringRef Message,
3540                                 SourceLocation Loc,
3541                                 const ObjCInterfaceDecl *UnknownObjCClass,
3542                                 const ObjCPropertyDecl  *ObjCProperty,
3543                                 bool ObjCPropertyAccess);
3544  
3545    bool makeUnavailableInSystemHeader(SourceLocation loc,
3546                                       UnavailableAttr::ImplicitReason reason);
3547  
3548    //===--------------------------------------------------------------------===//
3549    // Expression Parsing Callbacks: SemaExpr.cpp.
3550  
3551    bool CanUseDecl(NamedDecl *D);
3552    bool DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc,
3553                           const ObjCInterfaceDecl *UnknownObjCClass=nullptr,
3554                           bool ObjCPropertyAccess=false);
3555    void NoteDeletedFunction(FunctionDecl *FD);
3556    std::string getDeletedOrUnavailableSuffix(const FunctionDecl *FD);
3557    bool DiagnosePropertyAccessorMismatch(ObjCPropertyDecl *PD,
3558                                          ObjCMethodDecl *Getter,
3559                                          SourceLocation Loc);
3560    void DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc,
3561                               ArrayRef<Expr *> Args);
3562  
3563    void PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext,
3564                                         Decl *LambdaContextDecl = nullptr,
3565                                         bool IsDecltype = false);
3566    enum ReuseLambdaContextDecl_t { ReuseLambdaContextDecl };
3567    void PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext,
3568                                         ReuseLambdaContextDecl_t,
3569                                         bool IsDecltype = false);
3570    void PopExpressionEvaluationContext();
3571  
3572    void DiscardCleanupsInEvaluationContext();
3573  
3574    ExprResult TransformToPotentiallyEvaluated(Expr *E);
3575    ExprResult HandleExprEvaluationContextForTypeof(Expr *E);
3576  
3577    ExprResult ActOnConstantExpression(ExprResult Res);
3578  
3579    // Functions for marking a declaration referenced.  These functions also
3580    // contain the relevant logic for marking if a reference to a function or
3581    // variable is an odr-use (in the C++11 sense).  There are separate variants
3582    // for expressions referring to a decl; these exist because odr-use marking
3583    // needs to be delayed for some constant variables when we build one of the
3584    // named expressions.
3585    void MarkAnyDeclReferenced(SourceLocation Loc, Decl *D, bool OdrUse);
3586    void MarkFunctionReferenced(SourceLocation Loc, FunctionDecl *Func,
3587                                bool OdrUse = true);
3588    void MarkVariableReferenced(SourceLocation Loc, VarDecl *Var);
3589    void MarkDeclRefReferenced(DeclRefExpr *E);
3590    void MarkMemberReferenced(MemberExpr *E);
3591  
3592    void UpdateMarkingForLValueToRValue(Expr *E);
3593    void CleanupVarDeclMarking();
3594  
3595    enum TryCaptureKind {
3596      TryCapture_Implicit, TryCapture_ExplicitByVal, TryCapture_ExplicitByRef
3597    };
3598  
3599    /// \brief Try to capture the given variable.
3600    ///
3601    /// \param Var The variable to capture.
3602    ///
3603    /// \param Loc The location at which the capture occurs.
3604    ///
3605    /// \param Kind The kind of capture, which may be implicit (for either a
3606    /// block or a lambda), or explicit by-value or by-reference (for a lambda).
3607    ///
3608    /// \param EllipsisLoc The location of the ellipsis, if one is provided in
3609    /// an explicit lambda capture.
3610    ///
3611    /// \param BuildAndDiagnose Whether we are actually supposed to add the
3612    /// captures or diagnose errors. If false, this routine merely check whether
3613    /// the capture can occur without performing the capture itself or complaining
3614    /// if the variable cannot be captured.
3615    ///
3616    /// \param CaptureType Will be set to the type of the field used to capture
3617    /// this variable in the innermost block or lambda. Only valid when the
3618    /// variable can be captured.
3619    ///
3620    /// \param DeclRefType Will be set to the type of a reference to the capture
3621    /// from within the current scope. Only valid when the variable can be
3622    /// captured.
3623    ///
3624    /// \param FunctionScopeIndexToStopAt If non-null, it points to the index
3625    /// of the FunctionScopeInfo stack beyond which we do not attempt to capture.
3626    /// This is useful when enclosing lambdas must speculatively capture
3627    /// variables that may or may not be used in certain specializations of
3628    /// a nested generic lambda.
3629    ///
3630    /// \returns true if an error occurred (i.e., the variable cannot be
3631    /// captured) and false if the capture succeeded.
3632    bool tryCaptureVariable(VarDecl *Var, SourceLocation Loc, TryCaptureKind Kind,
3633                            SourceLocation EllipsisLoc, bool BuildAndDiagnose,
3634                            QualType &CaptureType,
3635                            QualType &DeclRefType,
3636                            const unsigned *const FunctionScopeIndexToStopAt);
3637  
3638    /// \brief Try to capture the given variable.
3639    bool tryCaptureVariable(VarDecl *Var, SourceLocation Loc,
3640                            TryCaptureKind Kind = TryCapture_Implicit,
3641                            SourceLocation EllipsisLoc = SourceLocation());
3642  
3643    /// \brief Checks if the variable must be captured.
3644    bool NeedToCaptureVariable(VarDecl *Var, SourceLocation Loc);
3645  
3646    /// \brief Given a variable, determine the type that a reference to that
3647    /// variable will have in the given scope.
3648    QualType getCapturedDeclRefType(VarDecl *Var, SourceLocation Loc);
3649  
3650    void MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T);
3651    void MarkDeclarationsReferencedInExpr(Expr *E,
3652                                          bool SkipLocalVariables = false);
3653  
3654    /// \brief Try to recover by turning the given expression into a
3655    /// call.  Returns true if recovery was attempted or an error was
3656    /// emitted; this may also leave the ExprResult invalid.
3657    bool tryToRecoverWithCall(ExprResult &E, const PartialDiagnostic &PD,
3658                              bool ForceComplain = false,
3659                              bool (*IsPlausibleResult)(QualType) = nullptr);
3660  
3661    /// \brief Figure out if an expression could be turned into a call.
3662    bool tryExprAsCall(Expr &E, QualType &ZeroArgCallReturnTy,
3663                       UnresolvedSetImpl &NonTemplateOverloads);
3664  
3665    /// \brief Conditionally issue a diagnostic based on the current
3666    /// evaluation context.
3667    ///
3668    /// \param Statement If Statement is non-null, delay reporting the
3669    /// diagnostic until the function body is parsed, and then do a basic
3670    /// reachability analysis to determine if the statement is reachable.
3671    /// If it is unreachable, the diagnostic will not be emitted.
3672    bool DiagRuntimeBehavior(SourceLocation Loc, const Stmt *Statement,
3673                             const PartialDiagnostic &PD);
3674  
3675    // Primary Expressions.
3676    SourceRange getExprRange(Expr *E) const;
3677  
3678    ExprResult ActOnIdExpression(
3679        Scope *S, CXXScopeSpec &SS, SourceLocation TemplateKWLoc,
3680        UnqualifiedId &Id, bool HasTrailingLParen, bool IsAddressOfOperand,
3681        std::unique_ptr<CorrectionCandidateCallback> CCC = nullptr,
3682        bool IsInlineAsmIdentifier = false, Token *KeywordReplacement = nullptr);
3683  
3684    void DecomposeUnqualifiedId(const UnqualifiedId &Id,
3685                                TemplateArgumentListInfo &Buffer,
3686                                DeclarationNameInfo &NameInfo,
3687                                const TemplateArgumentListInfo *&TemplateArgs);
3688  
3689    bool
3690    DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R,
3691                        std::unique_ptr<CorrectionCandidateCallback> CCC,
3692                        TemplateArgumentListInfo *ExplicitTemplateArgs = nullptr,
3693                        ArrayRef<Expr *> Args = None, TypoExpr **Out = nullptr);
3694  
3695    ExprResult LookupInObjCMethod(LookupResult &LookUp, Scope *S,
3696                                  IdentifierInfo *II,
3697                                  bool AllowBuiltinCreation=false);
3698  
3699    ExprResult ActOnDependentIdExpression(const CXXScopeSpec &SS,
3700                                          SourceLocation TemplateKWLoc,
3701                                          const DeclarationNameInfo &NameInfo,
3702                                          bool isAddressOfOperand,
3703                                  const TemplateArgumentListInfo *TemplateArgs);
3704  
3705    ExprResult BuildDeclRefExpr(ValueDecl *D, QualType Ty,
3706                                ExprValueKind VK,
3707                                SourceLocation Loc,
3708                                const CXXScopeSpec *SS = nullptr);
3709    ExprResult
3710    BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
3711                     const DeclarationNameInfo &NameInfo,
3712                     const CXXScopeSpec *SS = nullptr,
3713                     NamedDecl *FoundD = nullptr,
3714                     const TemplateArgumentListInfo *TemplateArgs = nullptr);
3715    ExprResult
3716    BuildAnonymousStructUnionMemberReference(
3717        const CXXScopeSpec &SS,
3718        SourceLocation nameLoc,
3719        IndirectFieldDecl *indirectField,
3720        DeclAccessPair FoundDecl = DeclAccessPair::make(nullptr, AS_none),
3721        Expr *baseObjectExpr = nullptr,
3722        SourceLocation opLoc = SourceLocation());
3723  
3724    ExprResult BuildPossibleImplicitMemberExpr(const CXXScopeSpec &SS,
3725                                               SourceLocation TemplateKWLoc,
3726                                               LookupResult &R,
3727                                  const TemplateArgumentListInfo *TemplateArgs,
3728                                               const Scope *S);
3729    ExprResult BuildImplicitMemberExpr(const CXXScopeSpec &SS,
3730                                       SourceLocation TemplateKWLoc,
3731                                       LookupResult &R,
3732                                  const TemplateArgumentListInfo *TemplateArgs,
3733                                       bool IsDefiniteInstance,
3734                                       const Scope *S);
3735    bool UseArgumentDependentLookup(const CXXScopeSpec &SS,
3736                                    const LookupResult &R,
3737                                    bool HasTrailingLParen);
3738  
3739    ExprResult
3740    BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS,
3741                                      const DeclarationNameInfo &NameInfo,
3742                                      bool IsAddressOfOperand, const Scope *S,
3743                                      TypeSourceInfo **RecoveryTSI = nullptr);
3744  
3745    ExprResult BuildDependentDeclRefExpr(const CXXScopeSpec &SS,
3746                                         SourceLocation TemplateKWLoc,
3747                                  const DeclarationNameInfo &NameInfo,
3748                                  const TemplateArgumentListInfo *TemplateArgs);
3749  
3750    ExprResult BuildDeclarationNameExpr(const CXXScopeSpec &SS,
3751                                        LookupResult &R,
3752                                        bool NeedsADL,
3753                                        bool AcceptInvalidDecl = false);
3754    ExprResult BuildDeclarationNameExpr(
3755        const CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo, NamedDecl *D,
3756        NamedDecl *FoundD = nullptr,
3757        const TemplateArgumentListInfo *TemplateArgs = nullptr,
3758        bool AcceptInvalidDecl = false);
3759  
3760    ExprResult BuildLiteralOperatorCall(LookupResult &R,
3761                        DeclarationNameInfo &SuffixInfo,
3762                        ArrayRef<Expr *> Args,
3763                        SourceLocation LitEndLoc,
3764                        TemplateArgumentListInfo *ExplicitTemplateArgs = nullptr);
3765  
3766    ExprResult BuildPredefinedExpr(SourceLocation Loc,
3767                                   PredefinedExpr::IdentType IT);
3768    ExprResult ActOnPredefinedExpr(SourceLocation Loc, tok::TokenKind Kind);
3769    ExprResult ActOnIntegerConstant(SourceLocation Loc, uint64_t Val);
3770  
3771    bool CheckLoopHintExpr(Expr *E, SourceLocation Loc);
3772  
3773    ExprResult ActOnNumericConstant(const Token &Tok, Scope *UDLScope = nullptr);
3774    ExprResult ActOnCharacterConstant(const Token &Tok,
3775                                      Scope *UDLScope = nullptr);
3776    ExprResult ActOnParenExpr(SourceLocation L, SourceLocation R, Expr *E);
3777    ExprResult ActOnParenListExpr(SourceLocation L,
3778                                  SourceLocation R,
3779                                  MultiExprArg Val);
3780  
3781    /// ActOnStringLiteral - The specified tokens were lexed as pasted string
3782    /// fragments (e.g. "foo" "bar" L"baz").
3783    ExprResult ActOnStringLiteral(ArrayRef<Token> StringToks,
3784                                  Scope *UDLScope = nullptr);
3785  
3786    ExprResult ActOnGenericSelectionExpr(SourceLocation KeyLoc,
3787                                         SourceLocation DefaultLoc,
3788                                         SourceLocation RParenLoc,
3789                                         Expr *ControllingExpr,
3790                                         ArrayRef<ParsedType> ArgTypes,
3791                                         ArrayRef<Expr *> ArgExprs);
3792    ExprResult CreateGenericSelectionExpr(SourceLocation KeyLoc,
3793                                          SourceLocation DefaultLoc,
3794                                          SourceLocation RParenLoc,
3795                                          Expr *ControllingExpr,
3796                                          ArrayRef<TypeSourceInfo *> Types,
3797                                          ArrayRef<Expr *> Exprs);
3798  
3799    // Binary/Unary Operators.  'Tok' is the token for the operator.
3800    ExprResult CreateBuiltinUnaryOp(SourceLocation OpLoc, UnaryOperatorKind Opc,
3801                                    Expr *InputExpr);
3802    ExprResult BuildUnaryOp(Scope *S, SourceLocation OpLoc,
3803                            UnaryOperatorKind Opc, Expr *Input);
3804    ExprResult ActOnUnaryOp(Scope *S, SourceLocation OpLoc,
3805                            tok::TokenKind Op, Expr *Input);
3806  
3807    QualType CheckAddressOfOperand(ExprResult &Operand, SourceLocation OpLoc);
3808  
3809    ExprResult CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo *TInfo,
3810                                              SourceLocation OpLoc,
3811                                              UnaryExprOrTypeTrait ExprKind,
3812                                              SourceRange R);
3813    ExprResult CreateUnaryExprOrTypeTraitExpr(Expr *E, SourceLocation OpLoc,
3814                                              UnaryExprOrTypeTrait ExprKind);
3815    ExprResult
3816      ActOnUnaryExprOrTypeTraitExpr(SourceLocation OpLoc,
3817                                    UnaryExprOrTypeTrait ExprKind,
3818                                    bool IsType, void *TyOrEx,
3819                                    SourceRange ArgRange);
3820  
3821    ExprResult CheckPlaceholderExpr(Expr *E);
3822    bool CheckVecStepExpr(Expr *E);
3823  
3824    bool CheckUnaryExprOrTypeTraitOperand(Expr *E, UnaryExprOrTypeTrait ExprKind);
3825    bool CheckUnaryExprOrTypeTraitOperand(QualType ExprType, SourceLocation OpLoc,
3826                                          SourceRange ExprRange,
3827                                          UnaryExprOrTypeTrait ExprKind);
3828    ExprResult ActOnSizeofParameterPackExpr(Scope *S,
3829                                            SourceLocation OpLoc,
3830                                            IdentifierInfo &Name,
3831                                            SourceLocation NameLoc,
3832                                            SourceLocation RParenLoc);
3833    ExprResult ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc,
3834                                   tok::TokenKind Kind, Expr *Input);
3835  
3836    ExprResult ActOnArraySubscriptExpr(Scope *S, Expr *Base, SourceLocation LLoc,
3837                                       Expr *Idx, SourceLocation RLoc);
3838    ExprResult CreateBuiltinArraySubscriptExpr(Expr *Base, SourceLocation LLoc,
3839                                               Expr *Idx, SourceLocation RLoc);
3840    ExprResult ActOnOMPArraySectionExpr(Expr *Base, SourceLocation LBLoc,
3841                                        Expr *LowerBound, SourceLocation ColonLoc,
3842                                        Expr *Length, SourceLocation RBLoc);
3843  
3844    // This struct is for use by ActOnMemberAccess to allow
3845    // BuildMemberReferenceExpr to be able to reinvoke ActOnMemberAccess after
3846    // changing the access operator from a '.' to a '->' (to see if that is the
3847    // change needed to fix an error about an unknown member, e.g. when the class
3848    // defines a custom operator->).
3849    struct ActOnMemberAccessExtraArgs {
3850      Scope *S;
3851      UnqualifiedId &Id;
3852      Decl *ObjCImpDecl;
3853    };
3854  
3855    ExprResult BuildMemberReferenceExpr(
3856        Expr *Base, QualType BaseType, SourceLocation OpLoc, bool IsArrow,
3857        CXXScopeSpec &SS, SourceLocation TemplateKWLoc,
3858        NamedDecl *FirstQualifierInScope, const DeclarationNameInfo &NameInfo,
3859        const TemplateArgumentListInfo *TemplateArgs,
3860        const Scope *S,
3861        ActOnMemberAccessExtraArgs *ExtraArgs = nullptr);
3862  
3863    ExprResult
3864    BuildMemberReferenceExpr(Expr *Base, QualType BaseType, SourceLocation OpLoc,
3865                             bool IsArrow, const CXXScopeSpec &SS,
3866                             SourceLocation TemplateKWLoc,
3867                             NamedDecl *FirstQualifierInScope, LookupResult &R,
3868                             const TemplateArgumentListInfo *TemplateArgs,
3869                             const Scope *S,
3870                             bool SuppressQualifierCheck = false,
3871                             ActOnMemberAccessExtraArgs *ExtraArgs = nullptr);
3872  
3873    ExprResult PerformMemberExprBaseConversion(Expr *Base, bool IsArrow);
3874  
3875    bool CheckQualifiedMemberReference(Expr *BaseExpr, QualType BaseType,
3876                                       const CXXScopeSpec &SS,
3877                                       const LookupResult &R);
3878  
3879    ExprResult ActOnDependentMemberExpr(Expr *Base, QualType BaseType,
3880                                        bool IsArrow, SourceLocation OpLoc,
3881                                        const CXXScopeSpec &SS,
3882                                        SourceLocation TemplateKWLoc,
3883                                        NamedDecl *FirstQualifierInScope,
3884                                 const DeclarationNameInfo &NameInfo,
3885                                 const TemplateArgumentListInfo *TemplateArgs);
3886  
3887    ExprResult ActOnMemberAccessExpr(Scope *S, Expr *Base,
3888                                     SourceLocation OpLoc,
3889                                     tok::TokenKind OpKind,
3890                                     CXXScopeSpec &SS,
3891                                     SourceLocation TemplateKWLoc,
3892                                     UnqualifiedId &Member,
3893                                     Decl *ObjCImpDecl);
3894  
3895    void ActOnDefaultCtorInitializers(Decl *CDtorDecl);
3896    bool ConvertArgumentsForCall(CallExpr *Call, Expr *Fn,
3897                                 FunctionDecl *FDecl,
3898                                 const FunctionProtoType *Proto,
3899                                 ArrayRef<Expr *> Args,
3900                                 SourceLocation RParenLoc,
3901                                 bool ExecConfig = false);
3902    void CheckStaticArrayArgument(SourceLocation CallLoc,
3903                                  ParmVarDecl *Param,
3904                                  const Expr *ArgExpr);
3905  
3906    /// ActOnCallExpr - Handle a call to Fn with the specified array of arguments.
3907    /// This provides the location of the left/right parens and a list of comma
3908    /// locations.
3909    ExprResult ActOnCallExpr(Scope *S, Expr *Fn, SourceLocation LParenLoc,
3910                             MultiExprArg ArgExprs, SourceLocation RParenLoc,
3911                             Expr *ExecConfig = nullptr,
3912                             bool IsExecConfig = false);
3913    ExprResult BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl,
3914                                     SourceLocation LParenLoc,
3915                                     ArrayRef<Expr *> Arg,
3916                                     SourceLocation RParenLoc,
3917                                     Expr *Config = nullptr,
3918                                     bool IsExecConfig = false);
3919  
3920    ExprResult ActOnCUDAExecConfigExpr(Scope *S, SourceLocation LLLLoc,
3921                                       MultiExprArg ExecConfig,
3922                                       SourceLocation GGGLoc);
3923  
3924    ExprResult ActOnCastExpr(Scope *S, SourceLocation LParenLoc,
3925                             Declarator &D, ParsedType &Ty,
3926                             SourceLocation RParenLoc, Expr *CastExpr);
3927    ExprResult BuildCStyleCastExpr(SourceLocation LParenLoc,
3928                                   TypeSourceInfo *Ty,
3929                                   SourceLocation RParenLoc,
3930                                   Expr *Op);
3931    CastKind PrepareScalarCast(ExprResult &src, QualType destType);
3932  
3933    /// \brief Build an altivec or OpenCL literal.
3934    ExprResult BuildVectorLiteral(SourceLocation LParenLoc,
3935                                  SourceLocation RParenLoc, Expr *E,
3936                                  TypeSourceInfo *TInfo);
3937  
3938    ExprResult MaybeConvertParenListExprToParenExpr(Scope *S, Expr *ME);
3939  
3940    ExprResult ActOnCompoundLiteral(SourceLocation LParenLoc,
3941                                    ParsedType Ty,
3942                                    SourceLocation RParenLoc,
3943                                    Expr *InitExpr);
3944  
3945    ExprResult BuildCompoundLiteralExpr(SourceLocation LParenLoc,
3946                                        TypeSourceInfo *TInfo,
3947                                        SourceLocation RParenLoc,
3948                                        Expr *LiteralExpr);
3949  
3950    ExprResult ActOnInitList(SourceLocation LBraceLoc,
3951                             MultiExprArg InitArgList,
3952                             SourceLocation RBraceLoc);
3953  
3954    ExprResult ActOnDesignatedInitializer(Designation &Desig,
3955                                          SourceLocation Loc,
3956                                          bool GNUSyntax,
3957                                          ExprResult Init);
3958  
3959  private:
3960    static BinaryOperatorKind ConvertTokenKindToBinaryOpcode(tok::TokenKind Kind);
3961  
3962  public:
3963    ExprResult ActOnBinOp(Scope *S, SourceLocation TokLoc,
3964                          tok::TokenKind Kind, Expr *LHSExpr, Expr *RHSExpr);
3965    ExprResult BuildBinOp(Scope *S, SourceLocation OpLoc,
3966                          BinaryOperatorKind Opc, Expr *LHSExpr, Expr *RHSExpr);
3967    ExprResult CreateBuiltinBinOp(SourceLocation OpLoc, BinaryOperatorKind Opc,
3968                                  Expr *LHSExpr, Expr *RHSExpr);
3969  
3970    /// ActOnConditionalOp - Parse a ?: operation.  Note that 'LHS' may be null
3971    /// in the case of a the GNU conditional expr extension.
3972    ExprResult ActOnConditionalOp(SourceLocation QuestionLoc,
3973                                  SourceLocation ColonLoc,
3974                                  Expr *CondExpr, Expr *LHSExpr, Expr *RHSExpr);
3975  
3976    /// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo".
3977    ExprResult ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc,
3978                              LabelDecl *TheDecl);
3979  
3980    void ActOnStartStmtExpr();
3981    ExprResult ActOnStmtExpr(SourceLocation LPLoc, Stmt *SubStmt,
3982                             SourceLocation RPLoc); // "({..})"
3983    void ActOnStmtExprError();
3984  
3985    // __builtin_offsetof(type, identifier(.identifier|[expr])*)
3986    struct OffsetOfComponent {
3987      SourceLocation LocStart, LocEnd;
3988      bool isBrackets;  // true if [expr], false if .ident
3989      union {
3990        IdentifierInfo *IdentInfo;
3991        Expr *E;
3992      } U;
3993    };
3994  
3995    /// __builtin_offsetof(type, a.b[123][456].c)
3996    ExprResult BuildBuiltinOffsetOf(SourceLocation BuiltinLoc,
3997                                    TypeSourceInfo *TInfo,
3998                                    ArrayRef<OffsetOfComponent> Components,
3999                                    SourceLocation RParenLoc);
4000    ExprResult ActOnBuiltinOffsetOf(Scope *S,
4001                                    SourceLocation BuiltinLoc,
4002                                    SourceLocation TypeLoc,
4003                                    ParsedType ParsedArgTy,
4004                                    ArrayRef<OffsetOfComponent> Components,
4005                                    SourceLocation RParenLoc);
4006  
4007    // __builtin_choose_expr(constExpr, expr1, expr2)
4008    ExprResult ActOnChooseExpr(SourceLocation BuiltinLoc,
4009                               Expr *CondExpr, Expr *LHSExpr,
4010                               Expr *RHSExpr, SourceLocation RPLoc);
4011  
4012    // __builtin_va_arg(expr, type)
4013    ExprResult ActOnVAArg(SourceLocation BuiltinLoc, Expr *E, ParsedType Ty,
4014                          SourceLocation RPLoc);
4015    ExprResult BuildVAArgExpr(SourceLocation BuiltinLoc, Expr *E,
4016                              TypeSourceInfo *TInfo, SourceLocation RPLoc);
4017  
4018    // __null
4019    ExprResult ActOnGNUNullExpr(SourceLocation TokenLoc);
4020  
4021    bool CheckCaseExpression(Expr *E);
4022  
4023    /// \brief Describes the result of an "if-exists" condition check.
4024    enum IfExistsResult {
4025      /// \brief The symbol exists.
4026      IER_Exists,
4027  
4028      /// \brief The symbol does not exist.
4029      IER_DoesNotExist,
4030  
4031      /// \brief The name is a dependent name, so the results will differ
4032      /// from one instantiation to the next.
4033      IER_Dependent,
4034  
4035      /// \brief An error occurred.
4036      IER_Error
4037    };
4038  
4039    IfExistsResult
4040    CheckMicrosoftIfExistsSymbol(Scope *S, CXXScopeSpec &SS,
4041                                 const DeclarationNameInfo &TargetNameInfo);
4042  
4043    IfExistsResult
4044    CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc,
4045                                 bool IsIfExists, CXXScopeSpec &SS,
4046                                 UnqualifiedId &Name);
4047  
4048    StmtResult BuildMSDependentExistsStmt(SourceLocation KeywordLoc,
4049                                          bool IsIfExists,
4050                                          NestedNameSpecifierLoc QualifierLoc,
4051                                          DeclarationNameInfo NameInfo,
4052                                          Stmt *Nested);
4053    StmtResult ActOnMSDependentExistsStmt(SourceLocation KeywordLoc,
4054                                          bool IsIfExists,
4055                                          CXXScopeSpec &SS, UnqualifiedId &Name,
4056                                          Stmt *Nested);
4057  
4058    //===------------------------- "Block" Extension ------------------------===//
4059  
4060    /// ActOnBlockStart - This callback is invoked when a block literal is
4061    /// started.
4062    void ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope);
4063  
4064    /// ActOnBlockArguments - This callback allows processing of block arguments.
4065    /// If there are no arguments, this is still invoked.
4066    void ActOnBlockArguments(SourceLocation CaretLoc, Declarator &ParamInfo,
4067                             Scope *CurScope);
4068  
4069    /// ActOnBlockError - If there is an error parsing a block, this callback
4070    /// is invoked to pop the information about the block from the action impl.
4071    void ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope);
4072  
4073    /// ActOnBlockStmtExpr - This is called when the body of a block statement
4074    /// literal was successfully completed.  ^(int x){...}
4075    ExprResult ActOnBlockStmtExpr(SourceLocation CaretLoc, Stmt *Body,
4076                                  Scope *CurScope);
4077  
4078    //===---------------------------- Clang Extensions ----------------------===//
4079  
4080    /// __builtin_convertvector(...)
4081    ExprResult ActOnConvertVectorExpr(Expr *E, ParsedType ParsedDestTy,
4082                                      SourceLocation BuiltinLoc,
4083                                      SourceLocation RParenLoc);
4084  
4085    //===---------------------------- OpenCL Features -----------------------===//
4086  
4087    /// __builtin_astype(...)
4088    ExprResult ActOnAsTypeExpr(Expr *E, ParsedType ParsedDestTy,
4089                               SourceLocation BuiltinLoc,
4090                               SourceLocation RParenLoc);
4091  
4092    //===---------------------------- C++ Features --------------------------===//
4093  
4094    // Act on C++ namespaces
4095    Decl *ActOnStartNamespaceDef(Scope *S, SourceLocation InlineLoc,
4096                                 SourceLocation NamespaceLoc,
4097                                 SourceLocation IdentLoc,
4098                                 IdentifierInfo *Ident,
4099                                 SourceLocation LBrace,
4100                                 AttributeList *AttrList,
4101                                 UsingDirectiveDecl * &UsingDecl);
4102    void ActOnFinishNamespaceDef(Decl *Dcl, SourceLocation RBrace);
4103  
4104    NamespaceDecl *getStdNamespace() const;
4105    NamespaceDecl *getOrCreateStdNamespace();
4106  
4107    CXXRecordDecl *getStdBadAlloc() const;
4108  
4109    /// \brief Tests whether Ty is an instance of std::initializer_list and, if
4110    /// it is and Element is not NULL, assigns the element type to Element.
4111    bool isStdInitializerList(QualType Ty, QualType *Element);
4112  
4113    /// \brief Looks for the std::initializer_list template and instantiates it
4114    /// with Element, or emits an error if it's not found.
4115    ///
4116    /// \returns The instantiated template, or null on error.
4117    QualType BuildStdInitializerList(QualType Element, SourceLocation Loc);
4118  
4119    /// \brief Determine whether Ctor is an initializer-list constructor, as
4120    /// defined in [dcl.init.list]p2.
4121    bool isInitListConstructor(const CXXConstructorDecl *Ctor);
4122  
4123    Decl *ActOnUsingDirective(Scope *CurScope,
4124                              SourceLocation UsingLoc,
4125                              SourceLocation NamespcLoc,
4126                              CXXScopeSpec &SS,
4127                              SourceLocation IdentLoc,
4128                              IdentifierInfo *NamespcName,
4129                              AttributeList *AttrList);
4130  
4131    void PushUsingDirective(Scope *S, UsingDirectiveDecl *UDir);
4132  
4133    Decl *ActOnNamespaceAliasDef(Scope *CurScope,
4134                                 SourceLocation NamespaceLoc,
4135                                 SourceLocation AliasLoc,
4136                                 IdentifierInfo *Alias,
4137                                 CXXScopeSpec &SS,
4138                                 SourceLocation IdentLoc,
4139                                 IdentifierInfo *Ident);
4140  
4141    void HideUsingShadowDecl(Scope *S, UsingShadowDecl *Shadow);
4142    bool CheckUsingShadowDecl(UsingDecl *UD, NamedDecl *Target,
4143                              const LookupResult &PreviousDecls,
4144                              UsingShadowDecl *&PrevShadow);
4145    UsingShadowDecl *BuildUsingShadowDecl(Scope *S, UsingDecl *UD,
4146                                          NamedDecl *Target,
4147                                          UsingShadowDecl *PrevDecl);
4148  
4149    bool CheckUsingDeclRedeclaration(SourceLocation UsingLoc,
4150                                     bool HasTypenameKeyword,
4151                                     const CXXScopeSpec &SS,
4152                                     SourceLocation NameLoc,
4153                                     const LookupResult &Previous);
4154    bool CheckUsingDeclQualifier(SourceLocation UsingLoc,
4155                                 const CXXScopeSpec &SS,
4156                                 const DeclarationNameInfo &NameInfo,
4157                                 SourceLocation NameLoc);
4158  
4159    NamedDecl *BuildUsingDeclaration(Scope *S, AccessSpecifier AS,
4160                                     SourceLocation UsingLoc,
4161                                     CXXScopeSpec &SS,
4162                                     DeclarationNameInfo NameInfo,
4163                                     AttributeList *AttrList,
4164                                     bool IsInstantiation,
4165                                     bool HasTypenameKeyword,
4166                                     SourceLocation TypenameLoc);
4167  
4168    bool CheckInheritingConstructorUsingDecl(UsingDecl *UD);
4169  
4170    Decl *ActOnUsingDeclaration(Scope *CurScope,
4171                                AccessSpecifier AS,
4172                                bool HasUsingKeyword,
4173                                SourceLocation UsingLoc,
4174                                CXXScopeSpec &SS,
4175                                UnqualifiedId &Name,
4176                                AttributeList *AttrList,
4177                                bool HasTypenameKeyword,
4178                                SourceLocation TypenameLoc);
4179    Decl *ActOnAliasDeclaration(Scope *CurScope,
4180                                AccessSpecifier AS,
4181                                MultiTemplateParamsArg TemplateParams,
4182                                SourceLocation UsingLoc,
4183                                UnqualifiedId &Name,
4184                                AttributeList *AttrList,
4185                                TypeResult Type,
4186                                Decl *DeclFromDeclSpec);
4187  
4188    /// BuildCXXConstructExpr - Creates a complete call to a constructor,
4189    /// including handling of its default argument expressions.
4190    ///
4191    /// \param ConstructKind - a CXXConstructExpr::ConstructionKind
4192    ExprResult
4193    BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
4194                          CXXConstructorDecl *Constructor, MultiExprArg Exprs,
4195                          bool HadMultipleCandidates, bool IsListInitialization,
4196                          bool IsStdInitListInitialization,
4197                          bool RequiresZeroInit, unsigned ConstructKind,
4198                          SourceRange ParenRange);
4199  
4200    // FIXME: Can we remove this and have the above BuildCXXConstructExpr check if
4201    // the constructor can be elidable?
4202    ExprResult
4203    BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
4204                          CXXConstructorDecl *Constructor, bool Elidable,
4205                          MultiExprArg Exprs, bool HadMultipleCandidates,
4206                          bool IsListInitialization,
4207                          bool IsStdInitListInitialization, bool RequiresZeroInit,
4208                          unsigned ConstructKind, SourceRange ParenRange);
4209  
4210    ExprResult BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field);
4211  
4212    /// BuildCXXDefaultArgExpr - Creates a CXXDefaultArgExpr, instantiating
4213    /// the default expr if needed.
4214    ExprResult BuildCXXDefaultArgExpr(SourceLocation CallLoc,
4215                                      FunctionDecl *FD,
4216                                      ParmVarDecl *Param);
4217  
4218    /// FinalizeVarWithDestructor - Prepare for calling destructor on the
4219    /// constructed variable.
4220    void FinalizeVarWithDestructor(VarDecl *VD, const RecordType *DeclInitType);
4221  
4222    /// \brief Helper class that collects exception specifications for
4223    /// implicitly-declared special member functions.
4224    class ImplicitExceptionSpecification {
4225      // Pointer to allow copying
4226      Sema *Self;
4227      // We order exception specifications thus:
4228      // noexcept is the most restrictive, but is only used in C++11.
4229      // throw() comes next.
4230      // Then a throw(collected exceptions)
4231      // Finally no specification, which is expressed as noexcept(false).
4232      // throw(...) is used instead if any called function uses it.
4233      ExceptionSpecificationType ComputedEST;
4234      llvm::SmallPtrSet<CanQualType, 4> ExceptionsSeen;
4235      SmallVector<QualType, 4> Exceptions;
4236  
ClearExceptions()4237      void ClearExceptions() {
4238        ExceptionsSeen.clear();
4239        Exceptions.clear();
4240      }
4241  
4242    public:
ImplicitExceptionSpecification(Sema & Self)4243      explicit ImplicitExceptionSpecification(Sema &Self)
4244        : Self(&Self), ComputedEST(EST_BasicNoexcept) {
4245        if (!Self.getLangOpts().CPlusPlus11)
4246          ComputedEST = EST_DynamicNone;
4247      }
4248  
4249      /// \brief Get the computed exception specification type.
getExceptionSpecType()4250      ExceptionSpecificationType getExceptionSpecType() const {
4251        assert(ComputedEST != EST_ComputedNoexcept &&
4252               "noexcept(expr) should not be a possible result");
4253        return ComputedEST;
4254      }
4255  
4256      /// \brief The number of exceptions in the exception specification.
size()4257      unsigned size() const { return Exceptions.size(); }
4258  
4259      /// \brief The set of exceptions in the exception specification.
data()4260      const QualType *data() const { return Exceptions.data(); }
4261  
4262      /// \brief Integrate another called method into the collected data.
4263      void CalledDecl(SourceLocation CallLoc, const CXXMethodDecl *Method);
4264  
4265      /// \brief Integrate an invoked expression into the collected data.
4266      void CalledExpr(Expr *E);
4267  
4268      /// \brief Overwrite an EPI's exception specification with this
4269      /// computed exception specification.
getExceptionSpec()4270      FunctionProtoType::ExceptionSpecInfo getExceptionSpec() const {
4271        FunctionProtoType::ExceptionSpecInfo ESI;
4272        ESI.Type = getExceptionSpecType();
4273        if (ESI.Type == EST_Dynamic) {
4274          ESI.Exceptions = Exceptions;
4275        } else if (ESI.Type == EST_None) {
4276          /// C++11 [except.spec]p14:
4277          ///   The exception-specification is noexcept(false) if the set of
4278          ///   potential exceptions of the special member function contains "any"
4279          ESI.Type = EST_ComputedNoexcept;
4280          ESI.NoexceptExpr = Self->ActOnCXXBoolLiteral(SourceLocation(),
4281                                                       tok::kw_false).get();
4282        }
4283        return ESI;
4284      }
4285    };
4286  
4287    /// \brief Determine what sort of exception specification a defaulted
4288    /// copy constructor of a class will have.
4289    ImplicitExceptionSpecification
4290    ComputeDefaultedDefaultCtorExceptionSpec(SourceLocation Loc,
4291                                             CXXMethodDecl *MD);
4292  
4293    /// \brief Determine what sort of exception specification a defaulted
4294    /// default constructor of a class will have, and whether the parameter
4295    /// will be const.
4296    ImplicitExceptionSpecification
4297    ComputeDefaultedCopyCtorExceptionSpec(CXXMethodDecl *MD);
4298  
4299    /// \brief Determine what sort of exception specification a defautled
4300    /// copy assignment operator of a class will have, and whether the
4301    /// parameter will be const.
4302    ImplicitExceptionSpecification
4303    ComputeDefaultedCopyAssignmentExceptionSpec(CXXMethodDecl *MD);
4304  
4305    /// \brief Determine what sort of exception specification a defaulted move
4306    /// constructor of a class will have.
4307    ImplicitExceptionSpecification
4308    ComputeDefaultedMoveCtorExceptionSpec(CXXMethodDecl *MD);
4309  
4310    /// \brief Determine what sort of exception specification a defaulted move
4311    /// assignment operator of a class will have.
4312    ImplicitExceptionSpecification
4313    ComputeDefaultedMoveAssignmentExceptionSpec(CXXMethodDecl *MD);
4314  
4315    /// \brief Determine what sort of exception specification a defaulted
4316    /// destructor of a class will have.
4317    ImplicitExceptionSpecification
4318    ComputeDefaultedDtorExceptionSpec(CXXMethodDecl *MD);
4319  
4320    /// \brief Determine what sort of exception specification an inheriting
4321    /// constructor of a class will have.
4322    ImplicitExceptionSpecification
4323    ComputeInheritingCtorExceptionSpec(CXXConstructorDecl *CD);
4324  
4325    /// \brief Evaluate the implicit exception specification for a defaulted
4326    /// special member function.
4327    void EvaluateImplicitExceptionSpec(SourceLocation Loc, CXXMethodDecl *MD);
4328  
4329    /// \brief Check the given exception-specification and update the
4330    /// exception specification information with the results.
4331    void checkExceptionSpecification(bool IsTopLevel,
4332                                     ExceptionSpecificationType EST,
4333                                     ArrayRef<ParsedType> DynamicExceptions,
4334                                     ArrayRef<SourceRange> DynamicExceptionRanges,
4335                                     Expr *NoexceptExpr,
4336                                     SmallVectorImpl<QualType> &Exceptions,
4337                                     FunctionProtoType::ExceptionSpecInfo &ESI);
4338  
4339    /// \brief Determine if we're in a case where we need to (incorrectly) eagerly
4340    /// parse an exception specification to work around a libstdc++ bug.
4341    bool isLibstdcxxEagerExceptionSpecHack(const Declarator &D);
4342  
4343    /// \brief Add an exception-specification to the given member function
4344    /// (or member function template). The exception-specification was parsed
4345    /// after the method itself was declared.
4346    void actOnDelayedExceptionSpecification(Decl *Method,
4347           ExceptionSpecificationType EST,
4348           SourceRange SpecificationRange,
4349           ArrayRef<ParsedType> DynamicExceptions,
4350           ArrayRef<SourceRange> DynamicExceptionRanges,
4351           Expr *NoexceptExpr);
4352  
4353    /// \brief Determine if a special member function should have a deleted
4354    /// definition when it is defaulted.
4355    bool ShouldDeleteSpecialMember(CXXMethodDecl *MD, CXXSpecialMember CSM,
4356                                   bool Diagnose = false);
4357  
4358    /// \brief Declare the implicit default constructor for the given class.
4359    ///
4360    /// \param ClassDecl The class declaration into which the implicit
4361    /// default constructor will be added.
4362    ///
4363    /// \returns The implicitly-declared default constructor.
4364    CXXConstructorDecl *DeclareImplicitDefaultConstructor(
4365                                                       CXXRecordDecl *ClassDecl);
4366  
4367    /// DefineImplicitDefaultConstructor - Checks for feasibility of
4368    /// defining this constructor as the default constructor.
4369    void DefineImplicitDefaultConstructor(SourceLocation CurrentLocation,
4370                                          CXXConstructorDecl *Constructor);
4371  
4372    /// \brief Declare the implicit destructor for the given class.
4373    ///
4374    /// \param ClassDecl The class declaration into which the implicit
4375    /// destructor will be added.
4376    ///
4377    /// \returns The implicitly-declared destructor.
4378    CXXDestructorDecl *DeclareImplicitDestructor(CXXRecordDecl *ClassDecl);
4379  
4380    /// DefineImplicitDestructor - Checks for feasibility of
4381    /// defining this destructor as the default destructor.
4382    void DefineImplicitDestructor(SourceLocation CurrentLocation,
4383                                  CXXDestructorDecl *Destructor);
4384  
4385    /// \brief Build an exception spec for destructors that don't have one.
4386    ///
4387    /// C++11 says that user-defined destructors with no exception spec get one
4388    /// that looks as if the destructor was implicitly declared.
4389    void AdjustDestructorExceptionSpec(CXXRecordDecl *ClassDecl,
4390                                       CXXDestructorDecl *Destructor);
4391  
4392    /// \brief Declare all inheriting constructors for the given class.
4393    ///
4394    /// \param ClassDecl The class declaration into which the inheriting
4395    /// constructors will be added.
4396    void DeclareInheritingConstructors(CXXRecordDecl *ClassDecl);
4397  
4398    /// \brief Define the specified inheriting constructor.
4399    void DefineInheritingConstructor(SourceLocation UseLoc,
4400                                     CXXConstructorDecl *Constructor);
4401  
4402    /// \brief Declare the implicit copy constructor for the given class.
4403    ///
4404    /// \param ClassDecl The class declaration into which the implicit
4405    /// copy constructor will be added.
4406    ///
4407    /// \returns The implicitly-declared copy constructor.
4408    CXXConstructorDecl *DeclareImplicitCopyConstructor(CXXRecordDecl *ClassDecl);
4409  
4410    /// DefineImplicitCopyConstructor - Checks for feasibility of
4411    /// defining this constructor as the copy constructor.
4412    void DefineImplicitCopyConstructor(SourceLocation CurrentLocation,
4413                                       CXXConstructorDecl *Constructor);
4414  
4415    /// \brief Declare the implicit move constructor for the given class.
4416    ///
4417    /// \param ClassDecl The Class declaration into which the implicit
4418    /// move constructor will be added.
4419    ///
4420    /// \returns The implicitly-declared move constructor, or NULL if it wasn't
4421    /// declared.
4422    CXXConstructorDecl *DeclareImplicitMoveConstructor(CXXRecordDecl *ClassDecl);
4423  
4424    /// DefineImplicitMoveConstructor - Checks for feasibility of
4425    /// defining this constructor as the move constructor.
4426    void DefineImplicitMoveConstructor(SourceLocation CurrentLocation,
4427                                       CXXConstructorDecl *Constructor);
4428  
4429    /// \brief Declare the implicit copy assignment operator for the given class.
4430    ///
4431    /// \param ClassDecl The class declaration into which the implicit
4432    /// copy assignment operator will be added.
4433    ///
4434    /// \returns The implicitly-declared copy assignment operator.
4435    CXXMethodDecl *DeclareImplicitCopyAssignment(CXXRecordDecl *ClassDecl);
4436  
4437    /// \brief Defines an implicitly-declared copy assignment operator.
4438    void DefineImplicitCopyAssignment(SourceLocation CurrentLocation,
4439                                      CXXMethodDecl *MethodDecl);
4440  
4441    /// \brief Declare the implicit move assignment operator for the given class.
4442    ///
4443    /// \param ClassDecl The Class declaration into which the implicit
4444    /// move assignment operator will be added.
4445    ///
4446    /// \returns The implicitly-declared move assignment operator, or NULL if it
4447    /// wasn't declared.
4448    CXXMethodDecl *DeclareImplicitMoveAssignment(CXXRecordDecl *ClassDecl);
4449  
4450    /// \brief Defines an implicitly-declared move assignment operator.
4451    void DefineImplicitMoveAssignment(SourceLocation CurrentLocation,
4452                                      CXXMethodDecl *MethodDecl);
4453  
4454    /// \brief Force the declaration of any implicitly-declared members of this
4455    /// class.
4456    void ForceDeclarationOfImplicitMembers(CXXRecordDecl *Class);
4457  
4458    /// \brief Determine whether the given function is an implicitly-deleted
4459    /// special member function.
4460    bool isImplicitlyDeleted(FunctionDecl *FD);
4461  
4462    /// \brief Check whether 'this' shows up in the type of a static member
4463    /// function after the (naturally empty) cv-qualifier-seq would be.
4464    ///
4465    /// \returns true if an error occurred.
4466    bool checkThisInStaticMemberFunctionType(CXXMethodDecl *Method);
4467  
4468    /// \brief Whether this' shows up in the exception specification of a static
4469    /// member function.
4470    bool checkThisInStaticMemberFunctionExceptionSpec(CXXMethodDecl *Method);
4471  
4472    /// \brief Check whether 'this' shows up in the attributes of the given
4473    /// static member function.
4474    ///
4475    /// \returns true if an error occurred.
4476    bool checkThisInStaticMemberFunctionAttributes(CXXMethodDecl *Method);
4477  
4478    /// MaybeBindToTemporary - If the passed in expression has a record type with
4479    /// a non-trivial destructor, this will return CXXBindTemporaryExpr. Otherwise
4480    /// it simply returns the passed in expression.
4481    ExprResult MaybeBindToTemporary(Expr *E);
4482  
4483    bool CompleteConstructorCall(CXXConstructorDecl *Constructor,
4484                                 MultiExprArg ArgsPtr,
4485                                 SourceLocation Loc,
4486                                 SmallVectorImpl<Expr*> &ConvertedArgs,
4487                                 bool AllowExplicit = false,
4488                                 bool IsListInitialization = false);
4489  
4490    ParsedType getInheritingConstructorName(CXXScopeSpec &SS,
4491                                            SourceLocation NameLoc,
4492                                            IdentifierInfo &Name);
4493  
4494    ParsedType getDestructorName(SourceLocation TildeLoc,
4495                                 IdentifierInfo &II, SourceLocation NameLoc,
4496                                 Scope *S, CXXScopeSpec &SS,
4497                                 ParsedType ObjectType,
4498                                 bool EnteringContext);
4499  
4500    ParsedType getDestructorType(const DeclSpec& DS, ParsedType ObjectType);
4501  
4502    // Checks that reinterpret casts don't have undefined behavior.
4503    void CheckCompatibleReinterpretCast(QualType SrcType, QualType DestType,
4504                                        bool IsDereference, SourceRange Range);
4505  
4506    /// ActOnCXXNamedCast - Parse {dynamic,static,reinterpret,const}_cast's.
4507    ExprResult ActOnCXXNamedCast(SourceLocation OpLoc,
4508                                 tok::TokenKind Kind,
4509                                 SourceLocation LAngleBracketLoc,
4510                                 Declarator &D,
4511                                 SourceLocation RAngleBracketLoc,
4512                                 SourceLocation LParenLoc,
4513                                 Expr *E,
4514                                 SourceLocation RParenLoc);
4515  
4516    ExprResult BuildCXXNamedCast(SourceLocation OpLoc,
4517                                 tok::TokenKind Kind,
4518                                 TypeSourceInfo *Ty,
4519                                 Expr *E,
4520                                 SourceRange AngleBrackets,
4521                                 SourceRange Parens);
4522  
4523    ExprResult BuildCXXTypeId(QualType TypeInfoType,
4524                              SourceLocation TypeidLoc,
4525                              TypeSourceInfo *Operand,
4526                              SourceLocation RParenLoc);
4527    ExprResult BuildCXXTypeId(QualType TypeInfoType,
4528                              SourceLocation TypeidLoc,
4529                              Expr *Operand,
4530                              SourceLocation RParenLoc);
4531  
4532    /// ActOnCXXTypeid - Parse typeid( something ).
4533    ExprResult ActOnCXXTypeid(SourceLocation OpLoc,
4534                              SourceLocation LParenLoc, bool isType,
4535                              void *TyOrExpr,
4536                              SourceLocation RParenLoc);
4537  
4538    ExprResult BuildCXXUuidof(QualType TypeInfoType,
4539                              SourceLocation TypeidLoc,
4540                              TypeSourceInfo *Operand,
4541                              SourceLocation RParenLoc);
4542    ExprResult BuildCXXUuidof(QualType TypeInfoType,
4543                              SourceLocation TypeidLoc,
4544                              Expr *Operand,
4545                              SourceLocation RParenLoc);
4546  
4547    /// ActOnCXXUuidof - Parse __uuidof( something ).
4548    ExprResult ActOnCXXUuidof(SourceLocation OpLoc,
4549                              SourceLocation LParenLoc, bool isType,
4550                              void *TyOrExpr,
4551                              SourceLocation RParenLoc);
4552  
4553    /// \brief Handle a C++1z fold-expression: ( expr op ... op expr ).
4554    ExprResult ActOnCXXFoldExpr(SourceLocation LParenLoc, Expr *LHS,
4555                                tok::TokenKind Operator,
4556                                SourceLocation EllipsisLoc, Expr *RHS,
4557                                SourceLocation RParenLoc);
4558    ExprResult BuildCXXFoldExpr(SourceLocation LParenLoc, Expr *LHS,
4559                                BinaryOperatorKind Operator,
4560                                SourceLocation EllipsisLoc, Expr *RHS,
4561                                SourceLocation RParenLoc);
4562    ExprResult BuildEmptyCXXFoldExpr(SourceLocation EllipsisLoc,
4563                                     BinaryOperatorKind Operator);
4564  
4565    //// ActOnCXXThis -  Parse 'this' pointer.
4566    ExprResult ActOnCXXThis(SourceLocation loc);
4567  
4568    /// \brief Try to retrieve the type of the 'this' pointer.
4569    ///
4570    /// \returns The type of 'this', if possible. Otherwise, returns a NULL type.
4571    QualType getCurrentThisType();
4572  
4573    /// \brief When non-NULL, the C++ 'this' expression is allowed despite the
4574    /// current context not being a non-static member function. In such cases,
4575    /// this provides the type used for 'this'.
4576    QualType CXXThisTypeOverride;
4577  
4578    /// \brief RAII object used to temporarily allow the C++ 'this' expression
4579    /// to be used, with the given qualifiers on the current class type.
4580    class CXXThisScopeRAII {
4581      Sema &S;
4582      QualType OldCXXThisTypeOverride;
4583      bool Enabled;
4584  
4585    public:
4586      /// \brief Introduce a new scope where 'this' may be allowed (when enabled),
4587      /// using the given declaration (which is either a class template or a
4588      /// class) along with the given qualifiers.
4589      /// along with the qualifiers placed on '*this'.
4590      CXXThisScopeRAII(Sema &S, Decl *ContextDecl, unsigned CXXThisTypeQuals,
4591                       bool Enabled = true);
4592  
4593      ~CXXThisScopeRAII();
4594    };
4595  
4596    /// \brief Make sure the value of 'this' is actually available in the current
4597    /// context, if it is a potentially evaluated context.
4598    ///
4599    /// \param Loc The location at which the capture of 'this' occurs.
4600    ///
4601    /// \param Explicit Whether 'this' is explicitly captured in a lambda
4602    /// capture list.
4603    ///
4604    /// \param FunctionScopeIndexToStopAt If non-null, it points to the index
4605    /// of the FunctionScopeInfo stack beyond which we do not attempt to capture.
4606    /// This is useful when enclosing lambdas must speculatively capture
4607    /// 'this' that may or may not be used in certain specializations of
4608    /// a nested generic lambda (depending on whether the name resolves to
4609    /// a non-static member function or a static function).
4610    /// \return returns 'true' if failed, 'false' if success.
4611    bool CheckCXXThisCapture(SourceLocation Loc, bool Explicit = false,
4612        bool BuildAndDiagnose = true,
4613        const unsigned *const FunctionScopeIndexToStopAt = nullptr);
4614  
4615    /// \brief Determine whether the given type is the type of *this that is used
4616    /// outside of the body of a member function for a type that is currently
4617    /// being defined.
4618    bool isThisOutsideMemberFunctionBody(QualType BaseType);
4619  
4620    /// ActOnCXXBoolLiteral - Parse {true,false} literals.
4621    ExprResult ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind);
4622  
4623  
4624    /// ActOnObjCBoolLiteral - Parse {__objc_yes,__objc_no} literals.
4625    ExprResult ActOnObjCBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind);
4626  
4627    /// ActOnCXXNullPtrLiteral - Parse 'nullptr'.
4628    ExprResult ActOnCXXNullPtrLiteral(SourceLocation Loc);
4629  
4630    //// ActOnCXXThrow -  Parse throw expressions.
4631    ExprResult ActOnCXXThrow(Scope *S, SourceLocation OpLoc, Expr *expr);
4632    ExprResult BuildCXXThrow(SourceLocation OpLoc, Expr *Ex,
4633                             bool IsThrownVarInScope);
4634    bool CheckCXXThrowOperand(SourceLocation ThrowLoc, QualType ThrowTy, Expr *E);
4635  
4636    /// ActOnCXXTypeConstructExpr - Parse construction of a specified type.
4637    /// Can be interpreted either as function-style casting ("int(x)")
4638    /// or class type construction ("ClassType(x,y,z)")
4639    /// or creation of a value-initialized type ("int()").
4640    ExprResult ActOnCXXTypeConstructExpr(ParsedType TypeRep,
4641                                         SourceLocation LParenLoc,
4642                                         MultiExprArg Exprs,
4643                                         SourceLocation RParenLoc);
4644  
4645    ExprResult BuildCXXTypeConstructExpr(TypeSourceInfo *Type,
4646                                         SourceLocation LParenLoc,
4647                                         MultiExprArg Exprs,
4648                                         SourceLocation RParenLoc);
4649  
4650    /// ActOnCXXNew - Parsed a C++ 'new' expression.
4651    ExprResult ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
4652                           SourceLocation PlacementLParen,
4653                           MultiExprArg PlacementArgs,
4654                           SourceLocation PlacementRParen,
4655                           SourceRange TypeIdParens, Declarator &D,
4656                           Expr *Initializer);
4657    ExprResult BuildCXXNew(SourceRange Range, bool UseGlobal,
4658                           SourceLocation PlacementLParen,
4659                           MultiExprArg PlacementArgs,
4660                           SourceLocation PlacementRParen,
4661                           SourceRange TypeIdParens,
4662                           QualType AllocType,
4663                           TypeSourceInfo *AllocTypeInfo,
4664                           Expr *ArraySize,
4665                           SourceRange DirectInitRange,
4666                           Expr *Initializer,
4667                           bool TypeMayContainAuto = true);
4668  
4669    bool CheckAllocatedType(QualType AllocType, SourceLocation Loc,
4670                            SourceRange R);
4671    bool FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range,
4672                                 bool UseGlobal, QualType AllocType, bool IsArray,
4673                                 MultiExprArg PlaceArgs,
4674                                 FunctionDecl *&OperatorNew,
4675                                 FunctionDecl *&OperatorDelete);
4676    bool FindAllocationOverload(SourceLocation StartLoc, SourceRange Range,
4677                                DeclarationName Name, MultiExprArg Args,
4678                                DeclContext *Ctx,
4679                                bool AllowMissing, FunctionDecl *&Operator,
4680                                bool Diagnose = true);
4681    void DeclareGlobalNewDelete();
4682    void DeclareGlobalAllocationFunction(DeclarationName Name, QualType Return,
4683                                         QualType Param1,
4684                                         QualType Param2 = QualType(),
4685                                         bool addRestrictAttr = false);
4686  
4687    bool FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD,
4688                                  DeclarationName Name, FunctionDecl* &Operator,
4689                                  bool Diagnose = true);
4690    FunctionDecl *FindUsualDeallocationFunction(SourceLocation StartLoc,
4691                                                bool CanProvideSize,
4692                                                DeclarationName Name);
4693  
4694    /// ActOnCXXDelete - Parsed a C++ 'delete' expression
4695    ExprResult ActOnCXXDelete(SourceLocation StartLoc,
4696                              bool UseGlobal, bool ArrayForm,
4697                              Expr *Operand);
4698  
4699    DeclResult ActOnCXXConditionDeclaration(Scope *S, Declarator &D);
4700    ExprResult CheckConditionVariable(VarDecl *ConditionVar,
4701                                      SourceLocation StmtLoc,
4702                                      bool ConvertToBoolean);
4703  
4704    ExprResult ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation LParen,
4705                                 Expr *Operand, SourceLocation RParen);
4706    ExprResult BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand,
4707                                    SourceLocation RParen);
4708  
4709    /// \brief Parsed one of the type trait support pseudo-functions.
4710    ExprResult ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
4711                              ArrayRef<ParsedType> Args,
4712                              SourceLocation RParenLoc);
4713    ExprResult BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
4714                              ArrayRef<TypeSourceInfo *> Args,
4715                              SourceLocation RParenLoc);
4716  
4717    /// ActOnArrayTypeTrait - Parsed one of the bianry type trait support
4718    /// pseudo-functions.
4719    ExprResult ActOnArrayTypeTrait(ArrayTypeTrait ATT,
4720                                   SourceLocation KWLoc,
4721                                   ParsedType LhsTy,
4722                                   Expr *DimExpr,
4723                                   SourceLocation RParen);
4724  
4725    ExprResult BuildArrayTypeTrait(ArrayTypeTrait ATT,
4726                                   SourceLocation KWLoc,
4727                                   TypeSourceInfo *TSInfo,
4728                                   Expr *DimExpr,
4729                                   SourceLocation RParen);
4730  
4731    /// ActOnExpressionTrait - Parsed one of the unary type trait support
4732    /// pseudo-functions.
4733    ExprResult ActOnExpressionTrait(ExpressionTrait OET,
4734                                    SourceLocation KWLoc,
4735                                    Expr *Queried,
4736                                    SourceLocation RParen);
4737  
4738    ExprResult BuildExpressionTrait(ExpressionTrait OET,
4739                                    SourceLocation KWLoc,
4740                                    Expr *Queried,
4741                                    SourceLocation RParen);
4742  
4743    ExprResult ActOnStartCXXMemberReference(Scope *S,
4744                                            Expr *Base,
4745                                            SourceLocation OpLoc,
4746                                            tok::TokenKind OpKind,
4747                                            ParsedType &ObjectType,
4748                                            bool &MayBePseudoDestructor);
4749  
4750    ExprResult BuildPseudoDestructorExpr(Expr *Base,
4751                                         SourceLocation OpLoc,
4752                                         tok::TokenKind OpKind,
4753                                         const CXXScopeSpec &SS,
4754                                         TypeSourceInfo *ScopeType,
4755                                         SourceLocation CCLoc,
4756                                         SourceLocation TildeLoc,
4757                                       PseudoDestructorTypeStorage DestroyedType);
4758  
4759    ExprResult ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
4760                                         SourceLocation OpLoc,
4761                                         tok::TokenKind OpKind,
4762                                         CXXScopeSpec &SS,
4763                                         UnqualifiedId &FirstTypeName,
4764                                         SourceLocation CCLoc,
4765                                         SourceLocation TildeLoc,
4766                                         UnqualifiedId &SecondTypeName);
4767  
4768    ExprResult ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
4769                                         SourceLocation OpLoc,
4770                                         tok::TokenKind OpKind,
4771                                         SourceLocation TildeLoc,
4772                                         const DeclSpec& DS);
4773  
4774    /// MaybeCreateExprWithCleanups - If the current full-expression
4775    /// requires any cleanups, surround it with a ExprWithCleanups node.
4776    /// Otherwise, just returns the passed-in expression.
4777    Expr *MaybeCreateExprWithCleanups(Expr *SubExpr);
4778    Stmt *MaybeCreateStmtWithCleanups(Stmt *SubStmt);
4779    ExprResult MaybeCreateExprWithCleanups(ExprResult SubExpr);
4780  
ActOnFinishFullExpr(Expr * Expr)4781    ExprResult ActOnFinishFullExpr(Expr *Expr) {
4782      return ActOnFinishFullExpr(Expr, Expr ? Expr->getExprLoc()
4783                                            : SourceLocation());
4784    }
4785    ExprResult ActOnFinishFullExpr(Expr *Expr, SourceLocation CC,
4786                                   bool DiscardedValue = false,
4787                                   bool IsConstexpr = false,
4788                                   bool IsLambdaInitCaptureInitializer = false);
4789    StmtResult ActOnFinishFullStmt(Stmt *Stmt);
4790  
4791    // Marks SS invalid if it represents an incomplete type.
4792    bool RequireCompleteDeclContext(CXXScopeSpec &SS, DeclContext *DC);
4793  
4794    DeclContext *computeDeclContext(QualType T);
4795    DeclContext *computeDeclContext(const CXXScopeSpec &SS,
4796                                    bool EnteringContext = false);
4797    bool isDependentScopeSpecifier(const CXXScopeSpec &SS);
4798    CXXRecordDecl *getCurrentInstantiationOf(NestedNameSpecifier *NNS);
4799  
4800    /// \brief The parser has parsed a global nested-name-specifier '::'.
4801    ///
4802    /// \param CCLoc The location of the '::'.
4803    ///
4804    /// \param SS The nested-name-specifier, which will be updated in-place
4805    /// to reflect the parsed nested-name-specifier.
4806    ///
4807    /// \returns true if an error occurred, false otherwise.
4808    bool ActOnCXXGlobalScopeSpecifier(SourceLocation CCLoc, CXXScopeSpec &SS);
4809  
4810    /// \brief The parser has parsed a '__super' nested-name-specifier.
4811    ///
4812    /// \param SuperLoc The location of the '__super' keyword.
4813    ///
4814    /// \param ColonColonLoc The location of the '::'.
4815    ///
4816    /// \param SS The nested-name-specifier, which will be updated in-place
4817    /// to reflect the parsed nested-name-specifier.
4818    ///
4819    /// \returns true if an error occurred, false otherwise.
4820    bool ActOnSuperScopeSpecifier(SourceLocation SuperLoc,
4821                                  SourceLocation ColonColonLoc, CXXScopeSpec &SS);
4822  
4823    bool isAcceptableNestedNameSpecifier(const NamedDecl *SD,
4824                                         bool *CanCorrect = nullptr);
4825    NamedDecl *FindFirstQualifierInScope(Scope *S, NestedNameSpecifier *NNS);
4826  
4827    bool isNonTypeNestedNameSpecifier(Scope *S, CXXScopeSpec &SS,
4828                                      SourceLocation IdLoc,
4829                                      IdentifierInfo &II,
4830                                      ParsedType ObjectType);
4831  
4832    bool BuildCXXNestedNameSpecifier(Scope *S,
4833                                     IdentifierInfo &Identifier,
4834                                     SourceLocation IdentifierLoc,
4835                                     SourceLocation CCLoc,
4836                                     QualType ObjectType,
4837                                     bool EnteringContext,
4838                                     CXXScopeSpec &SS,
4839                                     NamedDecl *ScopeLookupResult,
4840                                     bool ErrorRecoveryLookup,
4841                                     bool *IsCorrectedToColon = nullptr);
4842  
4843    /// \brief The parser has parsed a nested-name-specifier 'identifier::'.
4844    ///
4845    /// \param S The scope in which this nested-name-specifier occurs.
4846    ///
4847    /// \param Identifier The identifier preceding the '::'.
4848    ///
4849    /// \param IdentifierLoc The location of the identifier.
4850    ///
4851    /// \param CCLoc The location of the '::'.
4852    ///
4853    /// \param ObjectType The type of the object, if we're parsing
4854    /// nested-name-specifier in a member access expression.
4855    ///
4856    /// \param EnteringContext Whether we're entering the context nominated by
4857    /// this nested-name-specifier.
4858    ///
4859    /// \param SS The nested-name-specifier, which is both an input
4860    /// parameter (the nested-name-specifier before this type) and an
4861    /// output parameter (containing the full nested-name-specifier,
4862    /// including this new type).
4863    ///
4864    /// \param ErrorRecoveryLookup If true, then this method is called to improve
4865    /// error recovery. In this case do not emit error message.
4866    ///
4867    /// \param IsCorrectedToColon If not null, suggestions to replace '::' -> ':'
4868    /// are allowed.  The bool value pointed by this parameter is set to 'true'
4869    /// if the identifier is treated as if it was followed by ':', not '::'.
4870    ///
4871    /// \returns true if an error occurred, false otherwise.
4872    bool ActOnCXXNestedNameSpecifier(Scope *S,
4873                                     IdentifierInfo &Identifier,
4874                                     SourceLocation IdentifierLoc,
4875                                     SourceLocation CCLoc,
4876                                     ParsedType ObjectType,
4877                                     bool EnteringContext,
4878                                     CXXScopeSpec &SS,
4879                                     bool ErrorRecoveryLookup = false,
4880                                     bool *IsCorrectedToColon = nullptr);
4881  
4882    ExprResult ActOnDecltypeExpression(Expr *E);
4883  
4884    bool ActOnCXXNestedNameSpecifierDecltype(CXXScopeSpec &SS,
4885                                             const DeclSpec &DS,
4886                                             SourceLocation ColonColonLoc);
4887  
4888    bool IsInvalidUnlessNestedName(Scope *S, CXXScopeSpec &SS,
4889                                   IdentifierInfo &Identifier,
4890                                   SourceLocation IdentifierLoc,
4891                                   SourceLocation ColonLoc,
4892                                   ParsedType ObjectType,
4893                                   bool EnteringContext);
4894  
4895    /// \brief The parser has parsed a nested-name-specifier
4896    /// 'template[opt] template-name < template-args >::'.
4897    ///
4898    /// \param S The scope in which this nested-name-specifier occurs.
4899    ///
4900    /// \param SS The nested-name-specifier, which is both an input
4901    /// parameter (the nested-name-specifier before this type) and an
4902    /// output parameter (containing the full nested-name-specifier,
4903    /// including this new type).
4904    ///
4905    /// \param TemplateKWLoc the location of the 'template' keyword, if any.
4906    /// \param TemplateName the template name.
4907    /// \param TemplateNameLoc The location of the template name.
4908    /// \param LAngleLoc The location of the opening angle bracket  ('<').
4909    /// \param TemplateArgs The template arguments.
4910    /// \param RAngleLoc The location of the closing angle bracket  ('>').
4911    /// \param CCLoc The location of the '::'.
4912    ///
4913    /// \param EnteringContext Whether we're entering the context of the
4914    /// nested-name-specifier.
4915    ///
4916    ///
4917    /// \returns true if an error occurred, false otherwise.
4918    bool ActOnCXXNestedNameSpecifier(Scope *S,
4919                                     CXXScopeSpec &SS,
4920                                     SourceLocation TemplateKWLoc,
4921                                     TemplateTy TemplateName,
4922                                     SourceLocation TemplateNameLoc,
4923                                     SourceLocation LAngleLoc,
4924                                     ASTTemplateArgsPtr TemplateArgs,
4925                                     SourceLocation RAngleLoc,
4926                                     SourceLocation CCLoc,
4927                                     bool EnteringContext);
4928  
4929    /// \brief Given a C++ nested-name-specifier, produce an annotation value
4930    /// that the parser can use later to reconstruct the given
4931    /// nested-name-specifier.
4932    ///
4933    /// \param SS A nested-name-specifier.
4934    ///
4935    /// \returns A pointer containing all of the information in the
4936    /// nested-name-specifier \p SS.
4937    void *SaveNestedNameSpecifierAnnotation(CXXScopeSpec &SS);
4938  
4939    /// \brief Given an annotation pointer for a nested-name-specifier, restore
4940    /// the nested-name-specifier structure.
4941    ///
4942    /// \param Annotation The annotation pointer, produced by
4943    /// \c SaveNestedNameSpecifierAnnotation().
4944    ///
4945    /// \param AnnotationRange The source range corresponding to the annotation.
4946    ///
4947    /// \param SS The nested-name-specifier that will be updated with the contents
4948    /// of the annotation pointer.
4949    void RestoreNestedNameSpecifierAnnotation(void *Annotation,
4950                                              SourceRange AnnotationRange,
4951                                              CXXScopeSpec &SS);
4952  
4953    bool ShouldEnterDeclaratorScope(Scope *S, const CXXScopeSpec &SS);
4954  
4955    /// ActOnCXXEnterDeclaratorScope - Called when a C++ scope specifier (global
4956    /// scope or nested-name-specifier) is parsed, part of a declarator-id.
4957    /// After this method is called, according to [C++ 3.4.3p3], names should be
4958    /// looked up in the declarator-id's scope, until the declarator is parsed and
4959    /// ActOnCXXExitDeclaratorScope is called.
4960    /// The 'SS' should be a non-empty valid CXXScopeSpec.
4961    bool ActOnCXXEnterDeclaratorScope(Scope *S, CXXScopeSpec &SS);
4962  
4963    /// ActOnCXXExitDeclaratorScope - Called when a declarator that previously
4964    /// invoked ActOnCXXEnterDeclaratorScope(), is finished. 'SS' is the same
4965    /// CXXScopeSpec that was passed to ActOnCXXEnterDeclaratorScope as well.
4966    /// Used to indicate that names should revert to being looked up in the
4967    /// defining scope.
4968    void ActOnCXXExitDeclaratorScope(Scope *S, const CXXScopeSpec &SS);
4969  
4970    /// ActOnCXXEnterDeclInitializer - Invoked when we are about to parse an
4971    /// initializer for the declaration 'Dcl'.
4972    /// After this method is called, according to [C++ 3.4.1p13], if 'Dcl' is a
4973    /// static data member of class X, names should be looked up in the scope of
4974    /// class X.
4975    void ActOnCXXEnterDeclInitializer(Scope *S, Decl *Dcl);
4976  
4977    /// ActOnCXXExitDeclInitializer - Invoked after we are finished parsing an
4978    /// initializer for the declaration 'Dcl'.
4979    void ActOnCXXExitDeclInitializer(Scope *S, Decl *Dcl);
4980  
4981    /// \brief Create a new lambda closure type.
4982    CXXRecordDecl *createLambdaClosureType(SourceRange IntroducerRange,
4983                                           TypeSourceInfo *Info,
4984                                           bool KnownDependent,
4985                                           LambdaCaptureDefault CaptureDefault);
4986  
4987    /// \brief Start the definition of a lambda expression.
4988    CXXMethodDecl *startLambdaDefinition(CXXRecordDecl *Class,
4989                                         SourceRange IntroducerRange,
4990                                         TypeSourceInfo *MethodType,
4991                                         SourceLocation EndLoc,
4992                                         ArrayRef<ParmVarDecl *> Params);
4993  
4994    /// \brief Endow the lambda scope info with the relevant properties.
4995    void buildLambdaScope(sema::LambdaScopeInfo *LSI,
4996                          CXXMethodDecl *CallOperator,
4997                          SourceRange IntroducerRange,
4998                          LambdaCaptureDefault CaptureDefault,
4999                          SourceLocation CaptureDefaultLoc,
5000                          bool ExplicitParams,
5001                          bool ExplicitResultType,
5002                          bool Mutable);
5003  
5004    /// \brief Perform initialization analysis of the init-capture and perform
5005    /// any implicit conversions such as an lvalue-to-rvalue conversion if
5006    /// not being used to initialize a reference.
actOnLambdaInitCaptureInitialization(SourceLocation Loc,bool ByRef,IdentifierInfo * Id,LambdaCaptureInitKind InitKind,Expr * & Init)5007    ParsedType actOnLambdaInitCaptureInitialization(
5008        SourceLocation Loc, bool ByRef, IdentifierInfo *Id,
5009        LambdaCaptureInitKind InitKind, Expr *&Init) {
5010      return ParsedType::make(buildLambdaInitCaptureInitialization(
5011          Loc, ByRef, Id, InitKind != LambdaCaptureInitKind::CopyInit, Init));
5012    }
5013    QualType buildLambdaInitCaptureInitialization(SourceLocation Loc, bool ByRef,
5014                                                  IdentifierInfo *Id,
5015                                                  bool DirectInit, Expr *&Init);
5016  
5017    /// \brief Create a dummy variable within the declcontext of the lambda's
5018    ///  call operator, for name lookup purposes for a lambda init capture.
5019    ///
5020    ///  CodeGen handles emission of lambda captures, ignoring these dummy
5021    ///  variables appropriately.
5022    VarDecl *createLambdaInitCaptureVarDecl(SourceLocation Loc,
5023                                            QualType InitCaptureType,
5024                                            IdentifierInfo *Id,
5025                                            unsigned InitStyle, Expr *Init);
5026  
5027    /// \brief Build the implicit field for an init-capture.
5028    FieldDecl *buildInitCaptureField(sema::LambdaScopeInfo *LSI, VarDecl *Var);
5029  
5030    /// \brief Note that we have finished the explicit captures for the
5031    /// given lambda.
5032    void finishLambdaExplicitCaptures(sema::LambdaScopeInfo *LSI);
5033  
5034    /// \brief Introduce the lambda parameters into scope.
5035    void addLambdaParameters(CXXMethodDecl *CallOperator, Scope *CurScope);
5036  
5037    /// \brief Deduce a block or lambda's return type based on the return
5038    /// statements present in the body.
5039    void deduceClosureReturnType(sema::CapturingScopeInfo &CSI);
5040  
5041    /// ActOnStartOfLambdaDefinition - This is called just before we start
5042    /// parsing the body of a lambda; it analyzes the explicit captures and
5043    /// arguments, and sets up various data-structures for the body of the
5044    /// lambda.
5045    void ActOnStartOfLambdaDefinition(LambdaIntroducer &Intro,
5046                                      Declarator &ParamInfo, Scope *CurScope);
5047  
5048    /// ActOnLambdaError - If there is an error parsing a lambda, this callback
5049    /// is invoked to pop the information about the lambda.
5050    void ActOnLambdaError(SourceLocation StartLoc, Scope *CurScope,
5051                          bool IsInstantiation = false);
5052  
5053    /// ActOnLambdaExpr - This is called when the body of a lambda expression
5054    /// was successfully completed.
5055    ExprResult ActOnLambdaExpr(SourceLocation StartLoc, Stmt *Body,
5056                               Scope *CurScope);
5057  
5058    /// \brief Complete a lambda-expression having processed and attached the
5059    /// lambda body.
5060    ExprResult BuildLambdaExpr(SourceLocation StartLoc, SourceLocation EndLoc,
5061                               sema::LambdaScopeInfo *LSI);
5062  
5063    /// \brief Define the "body" of the conversion from a lambda object to a
5064    /// function pointer.
5065    ///
5066    /// This routine doesn't actually define a sensible body; rather, it fills
5067    /// in the initialization expression needed to copy the lambda object into
5068    /// the block, and IR generation actually generates the real body of the
5069    /// block pointer conversion.
5070    void DefineImplicitLambdaToFunctionPointerConversion(
5071           SourceLocation CurrentLoc, CXXConversionDecl *Conv);
5072  
5073    /// \brief Define the "body" of the conversion from a lambda object to a
5074    /// block pointer.
5075    ///
5076    /// This routine doesn't actually define a sensible body; rather, it fills
5077    /// in the initialization expression needed to copy the lambda object into
5078    /// the block, and IR generation actually generates the real body of the
5079    /// block pointer conversion.
5080    void DefineImplicitLambdaToBlockPointerConversion(SourceLocation CurrentLoc,
5081                                                      CXXConversionDecl *Conv);
5082  
5083    ExprResult BuildBlockForLambdaConversion(SourceLocation CurrentLocation,
5084                                             SourceLocation ConvLocation,
5085                                             CXXConversionDecl *Conv,
5086                                             Expr *Src);
5087  
5088    // ParseObjCStringLiteral - Parse Objective-C string literals.
5089    ExprResult ParseObjCStringLiteral(SourceLocation *AtLocs,
5090                                      Expr **Strings,
5091                                      unsigned NumStrings);
5092  
5093    ExprResult BuildObjCStringLiteral(SourceLocation AtLoc, StringLiteral *S);
5094  
5095    /// BuildObjCNumericLiteral - builds an ObjCBoxedExpr AST node for the
5096    /// numeric literal expression. Type of the expression will be "NSNumber *"
5097    /// or "id" if NSNumber is unavailable.
5098    ExprResult BuildObjCNumericLiteral(SourceLocation AtLoc, Expr *Number);
5099    ExprResult ActOnObjCBoolLiteral(SourceLocation AtLoc, SourceLocation ValueLoc,
5100                                    bool Value);
5101    ExprResult BuildObjCArrayLiteral(SourceRange SR, MultiExprArg Elements);
5102  
5103    /// BuildObjCBoxedExpr - builds an ObjCBoxedExpr AST node for the
5104    /// '@' prefixed parenthesized expression. The type of the expression will
5105    /// either be "NSNumber *", "NSString *" or "NSValue *" depending on the type
5106    /// of ValueType, which is allowed to be a built-in numeric type, "char *",
5107    /// "const char *" or C structure with attribute 'objc_boxable'.
5108    ExprResult BuildObjCBoxedExpr(SourceRange SR, Expr *ValueExpr);
5109  
5110    ExprResult BuildObjCSubscriptExpression(SourceLocation RB, Expr *BaseExpr,
5111                                            Expr *IndexExpr,
5112                                            ObjCMethodDecl *getterMethod,
5113                                            ObjCMethodDecl *setterMethod);
5114  
5115    ExprResult BuildObjCDictionaryLiteral(SourceRange SR,
5116                                          ObjCDictionaryElement *Elements,
5117                                          unsigned NumElements);
5118  
5119    ExprResult BuildObjCEncodeExpression(SourceLocation AtLoc,
5120                                    TypeSourceInfo *EncodedTypeInfo,
5121                                    SourceLocation RParenLoc);
5122    ExprResult BuildCXXMemberCallExpr(Expr *Exp, NamedDecl *FoundDecl,
5123                                      CXXConversionDecl *Method,
5124                                      bool HadMultipleCandidates);
5125  
5126    ExprResult ParseObjCEncodeExpression(SourceLocation AtLoc,
5127                                         SourceLocation EncodeLoc,
5128                                         SourceLocation LParenLoc,
5129                                         ParsedType Ty,
5130                                         SourceLocation RParenLoc);
5131  
5132    /// ParseObjCSelectorExpression - Build selector expression for \@selector
5133    ExprResult ParseObjCSelectorExpression(Selector Sel,
5134                                           SourceLocation AtLoc,
5135                                           SourceLocation SelLoc,
5136                                           SourceLocation LParenLoc,
5137                                           SourceLocation RParenLoc,
5138                                           bool WarnMultipleSelectors);
5139  
5140    /// ParseObjCProtocolExpression - Build protocol expression for \@protocol
5141    ExprResult ParseObjCProtocolExpression(IdentifierInfo * ProtocolName,
5142                                           SourceLocation AtLoc,
5143                                           SourceLocation ProtoLoc,
5144                                           SourceLocation LParenLoc,
5145                                           SourceLocation ProtoIdLoc,
5146                                           SourceLocation RParenLoc);
5147  
5148    //===--------------------------------------------------------------------===//
5149    // C++ Declarations
5150    //
5151    Decl *ActOnStartLinkageSpecification(Scope *S,
5152                                         SourceLocation ExternLoc,
5153                                         Expr *LangStr,
5154                                         SourceLocation LBraceLoc);
5155    Decl *ActOnFinishLinkageSpecification(Scope *S,
5156                                          Decl *LinkageSpec,
5157                                          SourceLocation RBraceLoc);
5158  
5159  
5160    //===--------------------------------------------------------------------===//
5161    // C++ Classes
5162    //
5163    bool isCurrentClassName(const IdentifierInfo &II, Scope *S,
5164                            const CXXScopeSpec *SS = nullptr);
5165    bool isCurrentClassNameTypo(IdentifierInfo *&II, const CXXScopeSpec *SS);
5166  
5167    bool ActOnAccessSpecifier(AccessSpecifier Access,
5168                              SourceLocation ASLoc,
5169                              SourceLocation ColonLoc,
5170                              AttributeList *Attrs = nullptr);
5171  
5172    NamedDecl *ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS,
5173                                   Declarator &D,
5174                                   MultiTemplateParamsArg TemplateParameterLists,
5175                                   Expr *BitfieldWidth, const VirtSpecifiers &VS,
5176                                   InClassInitStyle InitStyle);
5177  
5178    void ActOnStartCXXInClassMemberInitializer();
5179    void ActOnFinishCXXInClassMemberInitializer(Decl *VarDecl,
5180                                                SourceLocation EqualLoc,
5181                                                Expr *Init);
5182  
5183    MemInitResult ActOnMemInitializer(Decl *ConstructorD,
5184                                      Scope *S,
5185                                      CXXScopeSpec &SS,
5186                                      IdentifierInfo *MemberOrBase,
5187                                      ParsedType TemplateTypeTy,
5188                                      const DeclSpec &DS,
5189                                      SourceLocation IdLoc,
5190                                      SourceLocation LParenLoc,
5191                                      ArrayRef<Expr *> Args,
5192                                      SourceLocation RParenLoc,
5193                                      SourceLocation EllipsisLoc);
5194  
5195    MemInitResult ActOnMemInitializer(Decl *ConstructorD,
5196                                      Scope *S,
5197                                      CXXScopeSpec &SS,
5198                                      IdentifierInfo *MemberOrBase,
5199                                      ParsedType TemplateTypeTy,
5200                                      const DeclSpec &DS,
5201                                      SourceLocation IdLoc,
5202                                      Expr *InitList,
5203                                      SourceLocation EllipsisLoc);
5204  
5205    MemInitResult BuildMemInitializer(Decl *ConstructorD,
5206                                      Scope *S,
5207                                      CXXScopeSpec &SS,
5208                                      IdentifierInfo *MemberOrBase,
5209                                      ParsedType TemplateTypeTy,
5210                                      const DeclSpec &DS,
5211                                      SourceLocation IdLoc,
5212                                      Expr *Init,
5213                                      SourceLocation EllipsisLoc);
5214  
5215    MemInitResult BuildMemberInitializer(ValueDecl *Member,
5216                                         Expr *Init,
5217                                         SourceLocation IdLoc);
5218  
5219    MemInitResult BuildBaseInitializer(QualType BaseType,
5220                                       TypeSourceInfo *BaseTInfo,
5221                                       Expr *Init,
5222                                       CXXRecordDecl *ClassDecl,
5223                                       SourceLocation EllipsisLoc);
5224  
5225    MemInitResult BuildDelegatingInitializer(TypeSourceInfo *TInfo,
5226                                             Expr *Init,
5227                                             CXXRecordDecl *ClassDecl);
5228  
5229    bool SetDelegatingInitializer(CXXConstructorDecl *Constructor,
5230                                  CXXCtorInitializer *Initializer);
5231  
5232    bool SetCtorInitializers(CXXConstructorDecl *Constructor, bool AnyErrors,
5233                             ArrayRef<CXXCtorInitializer *> Initializers = None);
5234  
5235    void SetIvarInitializers(ObjCImplementationDecl *ObjCImplementation);
5236  
5237  
5238    /// MarkBaseAndMemberDestructorsReferenced - Given a record decl,
5239    /// mark all the non-trivial destructors of its members and bases as
5240    /// referenced.
5241    void MarkBaseAndMemberDestructorsReferenced(SourceLocation Loc,
5242                                                CXXRecordDecl *Record);
5243  
5244    /// \brief The list of classes whose vtables have been used within
5245    /// this translation unit, and the source locations at which the
5246    /// first use occurred.
5247    typedef std::pair<CXXRecordDecl*, SourceLocation> VTableUse;
5248  
5249    /// \brief The list of vtables that are required but have not yet been
5250    /// materialized.
5251    SmallVector<VTableUse, 16> VTableUses;
5252  
5253    /// \brief The set of classes whose vtables have been used within
5254    /// this translation unit, and a bit that will be true if the vtable is
5255    /// required to be emitted (otherwise, it should be emitted only if needed
5256    /// by code generation).
5257    llvm::DenseMap<CXXRecordDecl *, bool> VTablesUsed;
5258  
5259    /// \brief Load any externally-stored vtable uses.
5260    void LoadExternalVTableUses();
5261  
5262    /// \brief Note that the vtable for the given class was used at the
5263    /// given location.
5264    void MarkVTableUsed(SourceLocation Loc, CXXRecordDecl *Class,
5265                        bool DefinitionRequired = false);
5266  
5267    /// \brief Mark the exception specifications of all virtual member functions
5268    /// in the given class as needed.
5269    void MarkVirtualMemberExceptionSpecsNeeded(SourceLocation Loc,
5270                                               const CXXRecordDecl *RD);
5271  
5272    /// MarkVirtualMembersReferenced - Will mark all members of the given
5273    /// CXXRecordDecl referenced.
5274    void MarkVirtualMembersReferenced(SourceLocation Loc,
5275                                      const CXXRecordDecl *RD);
5276  
5277    /// \brief Define all of the vtables that have been used in this
5278    /// translation unit and reference any virtual members used by those
5279    /// vtables.
5280    ///
5281    /// \returns true if any work was done, false otherwise.
5282    bool DefineUsedVTables();
5283  
5284    void AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl);
5285  
5286    void ActOnMemInitializers(Decl *ConstructorDecl,
5287                              SourceLocation ColonLoc,
5288                              ArrayRef<CXXCtorInitializer*> MemInits,
5289                              bool AnyErrors);
5290  
5291    void checkClassLevelDLLAttribute(CXXRecordDecl *Class);
5292    void propagateDLLAttrToBaseClassTemplate(
5293        CXXRecordDecl *Class, Attr *ClassAttr,
5294        ClassTemplateSpecializationDecl *BaseTemplateSpec,
5295        SourceLocation BaseLoc);
5296    void CheckCompletedCXXClass(CXXRecordDecl *Record);
5297    void ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc,
5298                                           Decl *TagDecl,
5299                                           SourceLocation LBrac,
5300                                           SourceLocation RBrac,
5301                                           AttributeList *AttrList);
5302    void ActOnFinishCXXMemberDecls();
5303    void ActOnFinishCXXNonNestedClass(Decl *D);
5304  
5305    void ActOnReenterCXXMethodParameter(Scope *S, ParmVarDecl *Param);
5306    unsigned ActOnReenterTemplateScope(Scope *S, Decl *Template);
5307    void ActOnStartDelayedMemberDeclarations(Scope *S, Decl *Record);
5308    void ActOnStartDelayedCXXMethodDeclaration(Scope *S, Decl *Method);
5309    void ActOnDelayedCXXMethodParameter(Scope *S, Decl *Param);
5310    void ActOnFinishDelayedMemberDeclarations(Scope *S, Decl *Record);
5311    void ActOnFinishDelayedCXXMethodDeclaration(Scope *S, Decl *Method);
5312    void ActOnFinishDelayedMemberInitializers(Decl *Record);
5313    void MarkAsLateParsedTemplate(FunctionDecl *FD, Decl *FnD,
5314                                  CachedTokens &Toks);
5315    void UnmarkAsLateParsedTemplate(FunctionDecl *FD);
5316    bool IsInsideALocalClassWithinATemplateFunction();
5317  
5318    Decl *ActOnStaticAssertDeclaration(SourceLocation StaticAssertLoc,
5319                                       Expr *AssertExpr,
5320                                       Expr *AssertMessageExpr,
5321                                       SourceLocation RParenLoc);
5322    Decl *BuildStaticAssertDeclaration(SourceLocation StaticAssertLoc,
5323                                       Expr *AssertExpr,
5324                                       StringLiteral *AssertMessageExpr,
5325                                       SourceLocation RParenLoc,
5326                                       bool Failed);
5327  
5328    FriendDecl *CheckFriendTypeDecl(SourceLocation LocStart,
5329                                    SourceLocation FriendLoc,
5330                                    TypeSourceInfo *TSInfo);
5331    Decl *ActOnFriendTypeDecl(Scope *S, const DeclSpec &DS,
5332                              MultiTemplateParamsArg TemplateParams);
5333    NamedDecl *ActOnFriendFunctionDecl(Scope *S, Declarator &D,
5334                                       MultiTemplateParamsArg TemplateParams);
5335  
5336    QualType CheckConstructorDeclarator(Declarator &D, QualType R,
5337                                        StorageClass& SC);
5338    void CheckConstructor(CXXConstructorDecl *Constructor);
5339    QualType CheckDestructorDeclarator(Declarator &D, QualType R,
5340                                       StorageClass& SC);
5341    bool CheckDestructor(CXXDestructorDecl *Destructor);
5342    void CheckConversionDeclarator(Declarator &D, QualType &R,
5343                                   StorageClass& SC);
5344    Decl *ActOnConversionDeclarator(CXXConversionDecl *Conversion);
5345  
5346    void CheckExplicitlyDefaultedSpecialMember(CXXMethodDecl *MD);
5347    void CheckExplicitlyDefaultedMemberExceptionSpec(CXXMethodDecl *MD,
5348                                                     const FunctionProtoType *T);
5349    void CheckDelayedMemberExceptionSpecs();
5350  
5351    //===--------------------------------------------------------------------===//
5352    // C++ Derived Classes
5353    //
5354  
5355    /// ActOnBaseSpecifier - Parsed a base specifier
5356    CXXBaseSpecifier *CheckBaseSpecifier(CXXRecordDecl *Class,
5357                                         SourceRange SpecifierRange,
5358                                         bool Virtual, AccessSpecifier Access,
5359                                         TypeSourceInfo *TInfo,
5360                                         SourceLocation EllipsisLoc);
5361  
5362    BaseResult ActOnBaseSpecifier(Decl *classdecl,
5363                                  SourceRange SpecifierRange,
5364                                  ParsedAttributes &Attrs,
5365                                  bool Virtual, AccessSpecifier Access,
5366                                  ParsedType basetype,
5367                                  SourceLocation BaseLoc,
5368                                  SourceLocation EllipsisLoc);
5369  
5370    bool AttachBaseSpecifiers(CXXRecordDecl *Class, CXXBaseSpecifier **Bases,
5371                              unsigned NumBases);
5372    void ActOnBaseSpecifiers(Decl *ClassDecl, CXXBaseSpecifier **Bases,
5373                             unsigned NumBases);
5374  
5375    bool IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base);
5376    bool IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base,
5377                       CXXBasePaths &Paths);
5378  
5379    // FIXME: I don't like this name.
5380    void BuildBasePathArray(const CXXBasePaths &Paths, CXXCastPath &BasePath);
5381  
5382    bool CheckDerivedToBaseConversion(QualType Derived, QualType Base,
5383                                      SourceLocation Loc, SourceRange Range,
5384                                      CXXCastPath *BasePath = nullptr,
5385                                      bool IgnoreAccess = false);
5386    bool CheckDerivedToBaseConversion(QualType Derived, QualType Base,
5387                                      unsigned InaccessibleBaseID,
5388                                      unsigned AmbigiousBaseConvID,
5389                                      SourceLocation Loc, SourceRange Range,
5390                                      DeclarationName Name,
5391                                      CXXCastPath *BasePath);
5392  
5393    std::string getAmbiguousPathsDisplayString(CXXBasePaths &Paths);
5394  
5395    bool CheckOverridingFunctionAttributes(const CXXMethodDecl *New,
5396                                           const CXXMethodDecl *Old);
5397  
5398    /// CheckOverridingFunctionReturnType - Checks whether the return types are
5399    /// covariant, according to C++ [class.virtual]p5.
5400    bool CheckOverridingFunctionReturnType(const CXXMethodDecl *New,
5401                                           const CXXMethodDecl *Old);
5402  
5403    /// CheckOverridingFunctionExceptionSpec - Checks whether the exception
5404    /// spec is a subset of base spec.
5405    bool CheckOverridingFunctionExceptionSpec(const CXXMethodDecl *New,
5406                                              const CXXMethodDecl *Old);
5407  
5408    bool CheckPureMethod(CXXMethodDecl *Method, SourceRange InitRange);
5409  
5410    /// CheckOverrideControl - Check C++11 override control semantics.
5411    void CheckOverrideControl(NamedDecl *D);
5412  
5413    /// DiagnoseAbsenceOfOverrideControl - Diagnose if 'override' keyword was
5414    /// not used in the declaration of an overriding method.
5415    void DiagnoseAbsenceOfOverrideControl(NamedDecl *D);
5416  
5417    /// CheckForFunctionMarkedFinal - Checks whether a virtual member function
5418    /// overrides a virtual member function marked 'final', according to
5419    /// C++11 [class.virtual]p4.
5420    bool CheckIfOverriddenFunctionIsMarkedFinal(const CXXMethodDecl *New,
5421                                                const CXXMethodDecl *Old);
5422  
5423  
5424    //===--------------------------------------------------------------------===//
5425    // C++ Access Control
5426    //
5427  
5428    enum AccessResult {
5429      AR_accessible,
5430      AR_inaccessible,
5431      AR_dependent,
5432      AR_delayed
5433    };
5434  
5435    bool SetMemberAccessSpecifier(NamedDecl *MemberDecl,
5436                                  NamedDecl *PrevMemberDecl,
5437                                  AccessSpecifier LexicalAS);
5438  
5439    AccessResult CheckUnresolvedMemberAccess(UnresolvedMemberExpr *E,
5440                                             DeclAccessPair FoundDecl);
5441    AccessResult CheckUnresolvedLookupAccess(UnresolvedLookupExpr *E,
5442                                             DeclAccessPair FoundDecl);
5443    AccessResult CheckAllocationAccess(SourceLocation OperatorLoc,
5444                                       SourceRange PlacementRange,
5445                                       CXXRecordDecl *NamingClass,
5446                                       DeclAccessPair FoundDecl,
5447                                       bool Diagnose = true);
5448    AccessResult CheckConstructorAccess(SourceLocation Loc,
5449                                        CXXConstructorDecl *D,
5450                                        const InitializedEntity &Entity,
5451                                        AccessSpecifier Access,
5452                                        bool IsCopyBindingRefToTemp = false);
5453    AccessResult CheckConstructorAccess(SourceLocation Loc,
5454                                        CXXConstructorDecl *D,
5455                                        const InitializedEntity &Entity,
5456                                        AccessSpecifier Access,
5457                                        const PartialDiagnostic &PDiag);
5458    AccessResult CheckDestructorAccess(SourceLocation Loc,
5459                                       CXXDestructorDecl *Dtor,
5460                                       const PartialDiagnostic &PDiag,
5461                                       QualType objectType = QualType());
5462    AccessResult CheckFriendAccess(NamedDecl *D);
5463    AccessResult CheckMemberAccess(SourceLocation UseLoc,
5464                                   CXXRecordDecl *NamingClass,
5465                                   DeclAccessPair Found);
5466    AccessResult CheckMemberOperatorAccess(SourceLocation Loc,
5467                                           Expr *ObjectExpr,
5468                                           Expr *ArgExpr,
5469                                           DeclAccessPair FoundDecl);
5470    AccessResult CheckAddressOfMemberAccess(Expr *OvlExpr,
5471                                            DeclAccessPair FoundDecl);
5472    AccessResult CheckBaseClassAccess(SourceLocation AccessLoc,
5473                                      QualType Base, QualType Derived,
5474                                      const CXXBasePath &Path,
5475                                      unsigned DiagID,
5476                                      bool ForceCheck = false,
5477                                      bool ForceUnprivileged = false);
5478    void CheckLookupAccess(const LookupResult &R);
5479    bool IsSimplyAccessible(NamedDecl *decl, DeclContext *Ctx);
5480    bool isSpecialMemberAccessibleForDeletion(CXXMethodDecl *decl,
5481                                              AccessSpecifier access,
5482                                              QualType objectType);
5483  
5484    void HandleDependentAccessCheck(const DependentDiagnostic &DD,
5485                           const MultiLevelTemplateArgumentList &TemplateArgs);
5486    void PerformDependentDiagnostics(const DeclContext *Pattern,
5487                          const MultiLevelTemplateArgumentList &TemplateArgs);
5488  
5489    void HandleDelayedAccessCheck(sema::DelayedDiagnostic &DD, Decl *Ctx);
5490  
5491    /// \brief When true, access checking violations are treated as SFINAE
5492    /// failures rather than hard errors.
5493    bool AccessCheckingSFINAE;
5494  
5495    enum AbstractDiagSelID {
5496      AbstractNone = -1,
5497      AbstractReturnType,
5498      AbstractParamType,
5499      AbstractVariableType,
5500      AbstractFieldType,
5501      AbstractIvarType,
5502      AbstractSynthesizedIvarType,
5503      AbstractArrayType
5504    };
5505  
5506    bool isAbstractType(SourceLocation Loc, QualType T);
5507    bool RequireNonAbstractType(SourceLocation Loc, QualType T,
5508                                TypeDiagnoser &Diagnoser);
5509    template <typename... Ts>
RequireNonAbstractType(SourceLocation Loc,QualType T,unsigned DiagID,const Ts &...Args)5510    bool RequireNonAbstractType(SourceLocation Loc, QualType T, unsigned DiagID,
5511                                const Ts &...Args) {
5512      BoundTypeDiagnoser<Ts...> Diagnoser(DiagID, Args...);
5513      return RequireNonAbstractType(Loc, T, Diagnoser);
5514    }
5515  
5516    void DiagnoseAbstractType(const CXXRecordDecl *RD);
5517  
5518    //===--------------------------------------------------------------------===//
5519    // C++ Overloaded Operators [C++ 13.5]
5520    //
5521  
5522    bool CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl);
5523  
5524    bool CheckLiteralOperatorDeclaration(FunctionDecl *FnDecl);
5525  
5526    //===--------------------------------------------------------------------===//
5527    // C++ Templates [C++ 14]
5528    //
5529    void FilterAcceptableTemplateNames(LookupResult &R,
5530                                       bool AllowFunctionTemplates = true);
5531    bool hasAnyAcceptableTemplateNames(LookupResult &R,
5532                                       bool AllowFunctionTemplates = true);
5533  
5534    void LookupTemplateName(LookupResult &R, Scope *S, CXXScopeSpec &SS,
5535                            QualType ObjectType, bool EnteringContext,
5536                            bool &MemberOfUnknownSpecialization);
5537  
5538    TemplateNameKind isTemplateName(Scope *S,
5539                                    CXXScopeSpec &SS,
5540                                    bool hasTemplateKeyword,
5541                                    UnqualifiedId &Name,
5542                                    ParsedType ObjectType,
5543                                    bool EnteringContext,
5544                                    TemplateTy &Template,
5545                                    bool &MemberOfUnknownSpecialization);
5546  
5547    bool DiagnoseUnknownTemplateName(const IdentifierInfo &II,
5548                                     SourceLocation IILoc,
5549                                     Scope *S,
5550                                     const CXXScopeSpec *SS,
5551                                     TemplateTy &SuggestedTemplate,
5552                                     TemplateNameKind &SuggestedKind);
5553  
5554    void DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl);
5555    TemplateDecl *AdjustDeclIfTemplate(Decl *&Decl);
5556  
5557    Decl *ActOnTypeParameter(Scope *S, bool Typename,
5558                             SourceLocation EllipsisLoc,
5559                             SourceLocation KeyLoc,
5560                             IdentifierInfo *ParamName,
5561                             SourceLocation ParamNameLoc,
5562                             unsigned Depth, unsigned Position,
5563                             SourceLocation EqualLoc,
5564                             ParsedType DefaultArg);
5565  
5566    QualType CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc);
5567    Decl *ActOnNonTypeTemplateParameter(Scope *S, Declarator &D,
5568                                        unsigned Depth,
5569                                        unsigned Position,
5570                                        SourceLocation EqualLoc,
5571                                        Expr *DefaultArg);
5572    Decl *ActOnTemplateTemplateParameter(Scope *S,
5573                                         SourceLocation TmpLoc,
5574                                         TemplateParameterList *Params,
5575                                         SourceLocation EllipsisLoc,
5576                                         IdentifierInfo *ParamName,
5577                                         SourceLocation ParamNameLoc,
5578                                         unsigned Depth,
5579                                         unsigned Position,
5580                                         SourceLocation EqualLoc,
5581                                         ParsedTemplateArgument DefaultArg);
5582  
5583    TemplateParameterList *
5584    ActOnTemplateParameterList(unsigned Depth,
5585                               SourceLocation ExportLoc,
5586                               SourceLocation TemplateLoc,
5587                               SourceLocation LAngleLoc,
5588                               Decl **Params, unsigned NumParams,
5589                               SourceLocation RAngleLoc);
5590  
5591    /// \brief The context in which we are checking a template parameter list.
5592    enum TemplateParamListContext {
5593      TPC_ClassTemplate,
5594      TPC_VarTemplate,
5595      TPC_FunctionTemplate,
5596      TPC_ClassTemplateMember,
5597      TPC_FriendClassTemplate,
5598      TPC_FriendFunctionTemplate,
5599      TPC_FriendFunctionTemplateDefinition,
5600      TPC_TypeAliasTemplate
5601    };
5602  
5603    bool CheckTemplateParameterList(TemplateParameterList *NewParams,
5604                                    TemplateParameterList *OldParams,
5605                                    TemplateParamListContext TPC);
5606    TemplateParameterList *MatchTemplateParametersToScopeSpecifier(
5607        SourceLocation DeclStartLoc, SourceLocation DeclLoc,
5608        const CXXScopeSpec &SS, TemplateIdAnnotation *TemplateId,
5609        ArrayRef<TemplateParameterList *> ParamLists,
5610        bool IsFriend, bool &IsExplicitSpecialization, bool &Invalid);
5611  
5612    DeclResult CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK,
5613                                  SourceLocation KWLoc, CXXScopeSpec &SS,
5614                                  IdentifierInfo *Name, SourceLocation NameLoc,
5615                                  AttributeList *Attr,
5616                                  TemplateParameterList *TemplateParams,
5617                                  AccessSpecifier AS,
5618                                  SourceLocation ModulePrivateLoc,
5619                                  SourceLocation FriendLoc,
5620                                  unsigned NumOuterTemplateParamLists,
5621                              TemplateParameterList **OuterTemplateParamLists,
5622                                  SkipBodyInfo *SkipBody = nullptr);
5623  
5624    void translateTemplateArguments(const ASTTemplateArgsPtr &In,
5625                                    TemplateArgumentListInfo &Out);
5626  
5627    void NoteAllFoundTemplates(TemplateName Name);
5628  
5629    QualType CheckTemplateIdType(TemplateName Template,
5630                                 SourceLocation TemplateLoc,
5631                                TemplateArgumentListInfo &TemplateArgs);
5632  
5633    TypeResult
5634    ActOnTemplateIdType(CXXScopeSpec &SS, SourceLocation TemplateKWLoc,
5635                        TemplateTy Template, SourceLocation TemplateLoc,
5636                        SourceLocation LAngleLoc,
5637                        ASTTemplateArgsPtr TemplateArgs,
5638                        SourceLocation RAngleLoc,
5639                        bool IsCtorOrDtorName = false);
5640  
5641    /// \brief Parsed an elaborated-type-specifier that refers to a template-id,
5642    /// such as \c class T::template apply<U>.
5643    TypeResult ActOnTagTemplateIdType(TagUseKind TUK,
5644                                      TypeSpecifierType TagSpec,
5645                                      SourceLocation TagLoc,
5646                                      CXXScopeSpec &SS,
5647                                      SourceLocation TemplateKWLoc,
5648                                      TemplateTy TemplateD,
5649                                      SourceLocation TemplateLoc,
5650                                      SourceLocation LAngleLoc,
5651                                      ASTTemplateArgsPtr TemplateArgsIn,
5652                                      SourceLocation RAngleLoc);
5653  
5654    DeclResult ActOnVarTemplateSpecialization(
5655        Scope *S, Declarator &D, TypeSourceInfo *DI,
5656        SourceLocation TemplateKWLoc, TemplateParameterList *TemplateParams,
5657        StorageClass SC, bool IsPartialSpecialization);
5658  
5659    DeclResult CheckVarTemplateId(VarTemplateDecl *Template,
5660                                  SourceLocation TemplateLoc,
5661                                  SourceLocation TemplateNameLoc,
5662                                  const TemplateArgumentListInfo &TemplateArgs);
5663  
5664    ExprResult CheckVarTemplateId(const CXXScopeSpec &SS,
5665                                  const DeclarationNameInfo &NameInfo,
5666                                  VarTemplateDecl *Template,
5667                                  SourceLocation TemplateLoc,
5668                                  const TemplateArgumentListInfo *TemplateArgs);
5669  
5670    ExprResult BuildTemplateIdExpr(const CXXScopeSpec &SS,
5671                                   SourceLocation TemplateKWLoc,
5672                                   LookupResult &R,
5673                                   bool RequiresADL,
5674                                 const TemplateArgumentListInfo *TemplateArgs);
5675  
5676    ExprResult BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS,
5677                                            SourceLocation TemplateKWLoc,
5678                                 const DeclarationNameInfo &NameInfo,
5679                                 const TemplateArgumentListInfo *TemplateArgs);
5680  
5681    TemplateNameKind ActOnDependentTemplateName(Scope *S,
5682                                                CXXScopeSpec &SS,
5683                                                SourceLocation TemplateKWLoc,
5684                                                UnqualifiedId &Name,
5685                                                ParsedType ObjectType,
5686                                                bool EnteringContext,
5687                                                TemplateTy &Template);
5688  
5689    DeclResult
5690    ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec, TagUseKind TUK,
5691                                     SourceLocation KWLoc,
5692                                     SourceLocation ModulePrivateLoc,
5693                                     TemplateIdAnnotation &TemplateId,
5694                                     AttributeList *Attr,
5695                                   MultiTemplateParamsArg TemplateParameterLists,
5696                                     SkipBodyInfo *SkipBody = nullptr);
5697  
5698    Decl *ActOnTemplateDeclarator(Scope *S,
5699                                  MultiTemplateParamsArg TemplateParameterLists,
5700                                  Declarator &D);
5701  
5702    bool
5703    CheckSpecializationInstantiationRedecl(SourceLocation NewLoc,
5704                                           TemplateSpecializationKind NewTSK,
5705                                           NamedDecl *PrevDecl,
5706                                           TemplateSpecializationKind PrevTSK,
5707                                           SourceLocation PrevPtOfInstantiation,
5708                                           bool &SuppressNew);
5709  
5710    bool CheckDependentFunctionTemplateSpecialization(FunctionDecl *FD,
5711                      const TemplateArgumentListInfo &ExplicitTemplateArgs,
5712                                                      LookupResult &Previous);
5713  
5714    bool CheckFunctionTemplateSpecialization(FunctionDecl *FD,
5715                           TemplateArgumentListInfo *ExplicitTemplateArgs,
5716                                             LookupResult &Previous);
5717    bool CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous);
5718  
5719    DeclResult
5720    ActOnExplicitInstantiation(Scope *S,
5721                               SourceLocation ExternLoc,
5722                               SourceLocation TemplateLoc,
5723                               unsigned TagSpec,
5724                               SourceLocation KWLoc,
5725                               const CXXScopeSpec &SS,
5726                               TemplateTy Template,
5727                               SourceLocation TemplateNameLoc,
5728                               SourceLocation LAngleLoc,
5729                               ASTTemplateArgsPtr TemplateArgs,
5730                               SourceLocation RAngleLoc,
5731                               AttributeList *Attr);
5732  
5733    DeclResult
5734    ActOnExplicitInstantiation(Scope *S,
5735                               SourceLocation ExternLoc,
5736                               SourceLocation TemplateLoc,
5737                               unsigned TagSpec,
5738                               SourceLocation KWLoc,
5739                               CXXScopeSpec &SS,
5740                               IdentifierInfo *Name,
5741                               SourceLocation NameLoc,
5742                               AttributeList *Attr);
5743  
5744    DeclResult ActOnExplicitInstantiation(Scope *S,
5745                                          SourceLocation ExternLoc,
5746                                          SourceLocation TemplateLoc,
5747                                          Declarator &D);
5748  
5749    TemplateArgumentLoc
5750    SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template,
5751                                            SourceLocation TemplateLoc,
5752                                            SourceLocation RAngleLoc,
5753                                            Decl *Param,
5754                                            SmallVectorImpl<TemplateArgument>
5755                                              &Converted,
5756                                            bool &HasDefaultArg);
5757  
5758    /// \brief Specifies the context in which a particular template
5759    /// argument is being checked.
5760    enum CheckTemplateArgumentKind {
5761      /// \brief The template argument was specified in the code or was
5762      /// instantiated with some deduced template arguments.
5763      CTAK_Specified,
5764  
5765      /// \brief The template argument was deduced via template argument
5766      /// deduction.
5767      CTAK_Deduced,
5768  
5769      /// \brief The template argument was deduced from an array bound
5770      /// via template argument deduction.
5771      CTAK_DeducedFromArrayBound
5772    };
5773  
5774    bool CheckTemplateArgument(NamedDecl *Param,
5775                               TemplateArgumentLoc &Arg,
5776                               NamedDecl *Template,
5777                               SourceLocation TemplateLoc,
5778                               SourceLocation RAngleLoc,
5779                               unsigned ArgumentPackIndex,
5780                             SmallVectorImpl<TemplateArgument> &Converted,
5781                               CheckTemplateArgumentKind CTAK = CTAK_Specified);
5782  
5783    /// \brief Check that the given template arguments can be be provided to
5784    /// the given template, converting the arguments along the way.
5785    ///
5786    /// \param Template The template to which the template arguments are being
5787    /// provided.
5788    ///
5789    /// \param TemplateLoc The location of the template name in the source.
5790    ///
5791    /// \param TemplateArgs The list of template arguments. If the template is
5792    /// a template template parameter, this function may extend the set of
5793    /// template arguments to also include substituted, defaulted template
5794    /// arguments.
5795    ///
5796    /// \param PartialTemplateArgs True if the list of template arguments is
5797    /// intentionally partial, e.g., because we're checking just the initial
5798    /// set of template arguments.
5799    ///
5800    /// \param Converted Will receive the converted, canonicalized template
5801    /// arguments.
5802    ///
5803    /// \returns true if an error occurred, false otherwise.
5804    bool CheckTemplateArgumentList(TemplateDecl *Template,
5805                                   SourceLocation TemplateLoc,
5806                                   TemplateArgumentListInfo &TemplateArgs,
5807                                   bool PartialTemplateArgs,
5808                             SmallVectorImpl<TemplateArgument> &Converted);
5809  
5810    bool CheckTemplateTypeArgument(TemplateTypeParmDecl *Param,
5811                                   TemplateArgumentLoc &Arg,
5812                             SmallVectorImpl<TemplateArgument> &Converted);
5813  
5814    bool CheckTemplateArgument(TemplateTypeParmDecl *Param,
5815                               TypeSourceInfo *Arg);
5816    ExprResult CheckTemplateArgument(NonTypeTemplateParmDecl *Param,
5817                                     QualType InstantiatedParamType, Expr *Arg,
5818                                     TemplateArgument &Converted,
5819                                 CheckTemplateArgumentKind CTAK = CTAK_Specified);
5820    bool CheckTemplateArgument(TemplateTemplateParmDecl *Param,
5821                               TemplateArgumentLoc &Arg,
5822                               unsigned ArgumentPackIndex);
5823  
5824    ExprResult
5825    BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg,
5826                                            QualType ParamType,
5827                                            SourceLocation Loc);
5828    ExprResult
5829    BuildExpressionFromIntegralTemplateArgument(const TemplateArgument &Arg,
5830                                                SourceLocation Loc);
5831  
5832    /// \brief Enumeration describing how template parameter lists are compared
5833    /// for equality.
5834    enum TemplateParameterListEqualKind {
5835      /// \brief We are matching the template parameter lists of two templates
5836      /// that might be redeclarations.
5837      ///
5838      /// \code
5839      /// template<typename T> struct X;
5840      /// template<typename T> struct X;
5841      /// \endcode
5842      TPL_TemplateMatch,
5843  
5844      /// \brief We are matching the template parameter lists of two template
5845      /// template parameters as part of matching the template parameter lists
5846      /// of two templates that might be redeclarations.
5847      ///
5848      /// \code
5849      /// template<template<int I> class TT> struct X;
5850      /// template<template<int Value> class Other> struct X;
5851      /// \endcode
5852      TPL_TemplateTemplateParmMatch,
5853  
5854      /// \brief We are matching the template parameter lists of a template
5855      /// template argument against the template parameter lists of a template
5856      /// template parameter.
5857      ///
5858      /// \code
5859      /// template<template<int Value> class Metafun> struct X;
5860      /// template<int Value> struct integer_c;
5861      /// X<integer_c> xic;
5862      /// \endcode
5863      TPL_TemplateTemplateArgumentMatch
5864    };
5865  
5866    bool TemplateParameterListsAreEqual(TemplateParameterList *New,
5867                                        TemplateParameterList *Old,
5868                                        bool Complain,
5869                                        TemplateParameterListEqualKind Kind,
5870                                        SourceLocation TemplateArgLoc
5871                                          = SourceLocation());
5872  
5873    bool CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams);
5874  
5875    /// \brief Called when the parser has parsed a C++ typename
5876    /// specifier, e.g., "typename T::type".
5877    ///
5878    /// \param S The scope in which this typename type occurs.
5879    /// \param TypenameLoc the location of the 'typename' keyword
5880    /// \param SS the nested-name-specifier following the typename (e.g., 'T::').
5881    /// \param II the identifier we're retrieving (e.g., 'type' in the example).
5882    /// \param IdLoc the location of the identifier.
5883    TypeResult
5884    ActOnTypenameType(Scope *S, SourceLocation TypenameLoc,
5885                      const CXXScopeSpec &SS, const IdentifierInfo &II,
5886                      SourceLocation IdLoc);
5887  
5888    /// \brief Called when the parser has parsed a C++ typename
5889    /// specifier that ends in a template-id, e.g.,
5890    /// "typename MetaFun::template apply<T1, T2>".
5891    ///
5892    /// \param S The scope in which this typename type occurs.
5893    /// \param TypenameLoc the location of the 'typename' keyword
5894    /// \param SS the nested-name-specifier following the typename (e.g., 'T::').
5895    /// \param TemplateLoc the location of the 'template' keyword, if any.
5896    /// \param TemplateName The template name.
5897    /// \param TemplateNameLoc The location of the template name.
5898    /// \param LAngleLoc The location of the opening angle bracket  ('<').
5899    /// \param TemplateArgs The template arguments.
5900    /// \param RAngleLoc The location of the closing angle bracket  ('>').
5901    TypeResult
5902    ActOnTypenameType(Scope *S, SourceLocation TypenameLoc,
5903                      const CXXScopeSpec &SS,
5904                      SourceLocation TemplateLoc,
5905                      TemplateTy TemplateName,
5906                      SourceLocation TemplateNameLoc,
5907                      SourceLocation LAngleLoc,
5908                      ASTTemplateArgsPtr TemplateArgs,
5909                      SourceLocation RAngleLoc);
5910  
5911    QualType CheckTypenameType(ElaboratedTypeKeyword Keyword,
5912                               SourceLocation KeywordLoc,
5913                               NestedNameSpecifierLoc QualifierLoc,
5914                               const IdentifierInfo &II,
5915                               SourceLocation IILoc);
5916  
5917    TypeSourceInfo *RebuildTypeInCurrentInstantiation(TypeSourceInfo *T,
5918                                                      SourceLocation Loc,
5919                                                      DeclarationName Name);
5920    bool RebuildNestedNameSpecifierInCurrentInstantiation(CXXScopeSpec &SS);
5921  
5922    ExprResult RebuildExprInCurrentInstantiation(Expr *E);
5923    bool RebuildTemplateParamsInCurrentInstantiation(
5924                                                  TemplateParameterList *Params);
5925  
5926    std::string
5927    getTemplateArgumentBindingsText(const TemplateParameterList *Params,
5928                                    const TemplateArgumentList &Args);
5929  
5930    std::string
5931    getTemplateArgumentBindingsText(const TemplateParameterList *Params,
5932                                    const TemplateArgument *Args,
5933                                    unsigned NumArgs);
5934  
5935    //===--------------------------------------------------------------------===//
5936    // C++ Variadic Templates (C++0x [temp.variadic])
5937    //===--------------------------------------------------------------------===//
5938  
5939    /// Determine whether an unexpanded parameter pack might be permitted in this
5940    /// location. Useful for error recovery.
5941    bool isUnexpandedParameterPackPermitted();
5942  
5943    /// \brief The context in which an unexpanded parameter pack is
5944    /// being diagnosed.
5945    ///
5946    /// Note that the values of this enumeration line up with the first
5947    /// argument to the \c err_unexpanded_parameter_pack diagnostic.
5948    enum UnexpandedParameterPackContext {
5949      /// \brief An arbitrary expression.
5950      UPPC_Expression = 0,
5951  
5952      /// \brief The base type of a class type.
5953      UPPC_BaseType,
5954  
5955      /// \brief The type of an arbitrary declaration.
5956      UPPC_DeclarationType,
5957  
5958      /// \brief The type of a data member.
5959      UPPC_DataMemberType,
5960  
5961      /// \brief The size of a bit-field.
5962      UPPC_BitFieldWidth,
5963  
5964      /// \brief The expression in a static assertion.
5965      UPPC_StaticAssertExpression,
5966  
5967      /// \brief The fixed underlying type of an enumeration.
5968      UPPC_FixedUnderlyingType,
5969  
5970      /// \brief The enumerator value.
5971      UPPC_EnumeratorValue,
5972  
5973      /// \brief A using declaration.
5974      UPPC_UsingDeclaration,
5975  
5976      /// \brief A friend declaration.
5977      UPPC_FriendDeclaration,
5978  
5979      /// \brief A declaration qualifier.
5980      UPPC_DeclarationQualifier,
5981  
5982      /// \brief An initializer.
5983      UPPC_Initializer,
5984  
5985      /// \brief A default argument.
5986      UPPC_DefaultArgument,
5987  
5988      /// \brief The type of a non-type template parameter.
5989      UPPC_NonTypeTemplateParameterType,
5990  
5991      /// \brief The type of an exception.
5992      UPPC_ExceptionType,
5993  
5994      /// \brief Partial specialization.
5995      UPPC_PartialSpecialization,
5996  
5997      /// \brief Microsoft __if_exists.
5998      UPPC_IfExists,
5999  
6000      /// \brief Microsoft __if_not_exists.
6001      UPPC_IfNotExists,
6002  
6003      /// \brief Lambda expression.
6004      UPPC_Lambda,
6005  
6006      /// \brief Block expression,
6007      UPPC_Block
6008    };
6009  
6010    /// \brief Diagnose unexpanded parameter packs.
6011    ///
6012    /// \param Loc The location at which we should emit the diagnostic.
6013    ///
6014    /// \param UPPC The context in which we are diagnosing unexpanded
6015    /// parameter packs.
6016    ///
6017    /// \param Unexpanded the set of unexpanded parameter packs.
6018    ///
6019    /// \returns true if an error occurred, false otherwise.
6020    bool DiagnoseUnexpandedParameterPacks(SourceLocation Loc,
6021                                          UnexpandedParameterPackContext UPPC,
6022                                    ArrayRef<UnexpandedParameterPack> Unexpanded);
6023  
6024    /// \brief If the given type contains an unexpanded parameter pack,
6025    /// diagnose the error.
6026    ///
6027    /// \param Loc The source location where a diagnostc should be emitted.
6028    ///
6029    /// \param T The type that is being checked for unexpanded parameter
6030    /// packs.
6031    ///
6032    /// \returns true if an error occurred, false otherwise.
6033    bool DiagnoseUnexpandedParameterPack(SourceLocation Loc, TypeSourceInfo *T,
6034                                         UnexpandedParameterPackContext UPPC);
6035  
6036    /// \brief If the given expression contains an unexpanded parameter
6037    /// pack, diagnose the error.
6038    ///
6039    /// \param E The expression that is being checked for unexpanded
6040    /// parameter packs.
6041    ///
6042    /// \returns true if an error occurred, false otherwise.
6043    bool DiagnoseUnexpandedParameterPack(Expr *E,
6044                         UnexpandedParameterPackContext UPPC = UPPC_Expression);
6045  
6046    /// \brief If the given nested-name-specifier contains an unexpanded
6047    /// parameter pack, diagnose the error.
6048    ///
6049    /// \param SS The nested-name-specifier that is being checked for
6050    /// unexpanded parameter packs.
6051    ///
6052    /// \returns true if an error occurred, false otherwise.
6053    bool DiagnoseUnexpandedParameterPack(const CXXScopeSpec &SS,
6054                                         UnexpandedParameterPackContext UPPC);
6055  
6056    /// \brief If the given name contains an unexpanded parameter pack,
6057    /// diagnose the error.
6058    ///
6059    /// \param NameInfo The name (with source location information) that
6060    /// is being checked for unexpanded parameter packs.
6061    ///
6062    /// \returns true if an error occurred, false otherwise.
6063    bool DiagnoseUnexpandedParameterPack(const DeclarationNameInfo &NameInfo,
6064                                         UnexpandedParameterPackContext UPPC);
6065  
6066    /// \brief If the given template name contains an unexpanded parameter pack,
6067    /// diagnose the error.
6068    ///
6069    /// \param Loc The location of the template name.
6070    ///
6071    /// \param Template The template name that is being checked for unexpanded
6072    /// parameter packs.
6073    ///
6074    /// \returns true if an error occurred, false otherwise.
6075    bool DiagnoseUnexpandedParameterPack(SourceLocation Loc,
6076                                         TemplateName Template,
6077                                         UnexpandedParameterPackContext UPPC);
6078  
6079    /// \brief If the given template argument contains an unexpanded parameter
6080    /// pack, diagnose the error.
6081    ///
6082    /// \param Arg The template argument that is being checked for unexpanded
6083    /// parameter packs.
6084    ///
6085    /// \returns true if an error occurred, false otherwise.
6086    bool DiagnoseUnexpandedParameterPack(TemplateArgumentLoc Arg,
6087                                         UnexpandedParameterPackContext UPPC);
6088  
6089    /// \brief Collect the set of unexpanded parameter packs within the given
6090    /// template argument.
6091    ///
6092    /// \param Arg The template argument that will be traversed to find
6093    /// unexpanded parameter packs.
6094    void collectUnexpandedParameterPacks(TemplateArgument Arg,
6095                     SmallVectorImpl<UnexpandedParameterPack> &Unexpanded);
6096  
6097    /// \brief Collect the set of unexpanded parameter packs within the given
6098    /// template argument.
6099    ///
6100    /// \param Arg The template argument that will be traversed to find
6101    /// unexpanded parameter packs.
6102    void collectUnexpandedParameterPacks(TemplateArgumentLoc Arg,
6103                      SmallVectorImpl<UnexpandedParameterPack> &Unexpanded);
6104  
6105    /// \brief Collect the set of unexpanded parameter packs within the given
6106    /// type.
6107    ///
6108    /// \param T The type that will be traversed to find
6109    /// unexpanded parameter packs.
6110    void collectUnexpandedParameterPacks(QualType T,
6111                     SmallVectorImpl<UnexpandedParameterPack> &Unexpanded);
6112  
6113    /// \brief Collect the set of unexpanded parameter packs within the given
6114    /// type.
6115    ///
6116    /// \param TL The type that will be traversed to find
6117    /// unexpanded parameter packs.
6118    void collectUnexpandedParameterPacks(TypeLoc TL,
6119                     SmallVectorImpl<UnexpandedParameterPack> &Unexpanded);
6120  
6121    /// \brief Collect the set of unexpanded parameter packs within the given
6122    /// nested-name-specifier.
6123    ///
6124    /// \param SS The nested-name-specifier that will be traversed to find
6125    /// unexpanded parameter packs.
6126    void collectUnexpandedParameterPacks(CXXScopeSpec &SS,
6127                           SmallVectorImpl<UnexpandedParameterPack> &Unexpanded);
6128  
6129    /// \brief Collect the set of unexpanded parameter packs within the given
6130    /// name.
6131    ///
6132    /// \param NameInfo The name that will be traversed to find
6133    /// unexpanded parameter packs.
6134    void collectUnexpandedParameterPacks(const DeclarationNameInfo &NameInfo,
6135                           SmallVectorImpl<UnexpandedParameterPack> &Unexpanded);
6136  
6137    /// \brief Invoked when parsing a template argument followed by an
6138    /// ellipsis, which creates a pack expansion.
6139    ///
6140    /// \param Arg The template argument preceding the ellipsis, which
6141    /// may already be invalid.
6142    ///
6143    /// \param EllipsisLoc The location of the ellipsis.
6144    ParsedTemplateArgument ActOnPackExpansion(const ParsedTemplateArgument &Arg,
6145                                              SourceLocation EllipsisLoc);
6146  
6147    /// \brief Invoked when parsing a type followed by an ellipsis, which
6148    /// creates a pack expansion.
6149    ///
6150    /// \param Type The type preceding the ellipsis, which will become
6151    /// the pattern of the pack expansion.
6152    ///
6153    /// \param EllipsisLoc The location of the ellipsis.
6154    TypeResult ActOnPackExpansion(ParsedType Type, SourceLocation EllipsisLoc);
6155  
6156    /// \brief Construct a pack expansion type from the pattern of the pack
6157    /// expansion.
6158    TypeSourceInfo *CheckPackExpansion(TypeSourceInfo *Pattern,
6159                                       SourceLocation EllipsisLoc,
6160                                       Optional<unsigned> NumExpansions);
6161  
6162    /// \brief Construct a pack expansion type from the pattern of the pack
6163    /// expansion.
6164    QualType CheckPackExpansion(QualType Pattern,
6165                                SourceRange PatternRange,
6166                                SourceLocation EllipsisLoc,
6167                                Optional<unsigned> NumExpansions);
6168  
6169    /// \brief Invoked when parsing an expression followed by an ellipsis, which
6170    /// creates a pack expansion.
6171    ///
6172    /// \param Pattern The expression preceding the ellipsis, which will become
6173    /// the pattern of the pack expansion.
6174    ///
6175    /// \param EllipsisLoc The location of the ellipsis.
6176    ExprResult ActOnPackExpansion(Expr *Pattern, SourceLocation EllipsisLoc);
6177  
6178    /// \brief Invoked when parsing an expression followed by an ellipsis, which
6179    /// creates a pack expansion.
6180    ///
6181    /// \param Pattern The expression preceding the ellipsis, which will become
6182    /// the pattern of the pack expansion.
6183    ///
6184    /// \param EllipsisLoc The location of the ellipsis.
6185    ExprResult CheckPackExpansion(Expr *Pattern, SourceLocation EllipsisLoc,
6186                                  Optional<unsigned> NumExpansions);
6187  
6188    /// \brief Determine whether we could expand a pack expansion with the
6189    /// given set of parameter packs into separate arguments by repeatedly
6190    /// transforming the pattern.
6191    ///
6192    /// \param EllipsisLoc The location of the ellipsis that identifies the
6193    /// pack expansion.
6194    ///
6195    /// \param PatternRange The source range that covers the entire pattern of
6196    /// the pack expansion.
6197    ///
6198    /// \param Unexpanded The set of unexpanded parameter packs within the
6199    /// pattern.
6200    ///
6201    /// \param ShouldExpand Will be set to \c true if the transformer should
6202    /// expand the corresponding pack expansions into separate arguments. When
6203    /// set, \c NumExpansions must also be set.
6204    ///
6205    /// \param RetainExpansion Whether the caller should add an unexpanded
6206    /// pack expansion after all of the expanded arguments. This is used
6207    /// when extending explicitly-specified template argument packs per
6208    /// C++0x [temp.arg.explicit]p9.
6209    ///
6210    /// \param NumExpansions The number of separate arguments that will be in
6211    /// the expanded form of the corresponding pack expansion. This is both an
6212    /// input and an output parameter, which can be set by the caller if the
6213    /// number of expansions is known a priori (e.g., due to a prior substitution)
6214    /// and will be set by the callee when the number of expansions is known.
6215    /// The callee must set this value when \c ShouldExpand is \c true; it may
6216    /// set this value in other cases.
6217    ///
6218    /// \returns true if an error occurred (e.g., because the parameter packs
6219    /// are to be instantiated with arguments of different lengths), false
6220    /// otherwise. If false, \c ShouldExpand (and possibly \c NumExpansions)
6221    /// must be set.
6222    bool CheckParameterPacksForExpansion(SourceLocation EllipsisLoc,
6223                                         SourceRange PatternRange,
6224                               ArrayRef<UnexpandedParameterPack> Unexpanded,
6225                               const MultiLevelTemplateArgumentList &TemplateArgs,
6226                                         bool &ShouldExpand,
6227                                         bool &RetainExpansion,
6228                                         Optional<unsigned> &NumExpansions);
6229  
6230    /// \brief Determine the number of arguments in the given pack expansion
6231    /// type.
6232    ///
6233    /// This routine assumes that the number of arguments in the expansion is
6234    /// consistent across all of the unexpanded parameter packs in its pattern.
6235    ///
6236    /// Returns an empty Optional if the type can't be expanded.
6237    Optional<unsigned> getNumArgumentsInExpansion(QualType T,
6238        const MultiLevelTemplateArgumentList &TemplateArgs);
6239  
6240    /// \brief Determine whether the given declarator contains any unexpanded
6241    /// parameter packs.
6242    ///
6243    /// This routine is used by the parser to disambiguate function declarators
6244    /// with an ellipsis prior to the ')', e.g.,
6245    ///
6246    /// \code
6247    ///   void f(T...);
6248    /// \endcode
6249    ///
6250    /// To determine whether we have an (unnamed) function parameter pack or
6251    /// a variadic function.
6252    ///
6253    /// \returns true if the declarator contains any unexpanded parameter packs,
6254    /// false otherwise.
6255    bool containsUnexpandedParameterPacks(Declarator &D);
6256  
6257    /// \brief Returns the pattern of the pack expansion for a template argument.
6258    ///
6259    /// \param OrigLoc The template argument to expand.
6260    ///
6261    /// \param Ellipsis Will be set to the location of the ellipsis.
6262    ///
6263    /// \param NumExpansions Will be set to the number of expansions that will
6264    /// be generated from this pack expansion, if known a priori.
6265    TemplateArgumentLoc getTemplateArgumentPackExpansionPattern(
6266        TemplateArgumentLoc OrigLoc,
6267        SourceLocation &Ellipsis,
6268        Optional<unsigned> &NumExpansions) const;
6269  
6270    //===--------------------------------------------------------------------===//
6271    // C++ Template Argument Deduction (C++ [temp.deduct])
6272    //===--------------------------------------------------------------------===//
6273  
6274    QualType adjustCCAndNoReturn(QualType ArgFunctionType, QualType FunctionType);
6275  
6276    /// \brief Describes the result of template argument deduction.
6277    ///
6278    /// The TemplateDeductionResult enumeration describes the result of
6279    /// template argument deduction, as returned from
6280    /// DeduceTemplateArguments(). The separate TemplateDeductionInfo
6281    /// structure provides additional information about the results of
6282    /// template argument deduction, e.g., the deduced template argument
6283    /// list (if successful) or the specific template parameters or
6284    /// deduced arguments that were involved in the failure.
6285    enum TemplateDeductionResult {
6286      /// \brief Template argument deduction was successful.
6287      TDK_Success = 0,
6288      /// \brief The declaration was invalid; do nothing.
6289      TDK_Invalid,
6290      /// \brief Template argument deduction exceeded the maximum template
6291      /// instantiation depth (which has already been diagnosed).
6292      TDK_InstantiationDepth,
6293      /// \brief Template argument deduction did not deduce a value
6294      /// for every template parameter.
6295      TDK_Incomplete,
6296      /// \brief Template argument deduction produced inconsistent
6297      /// deduced values for the given template parameter.
6298      TDK_Inconsistent,
6299      /// \brief Template argument deduction failed due to inconsistent
6300      /// cv-qualifiers on a template parameter type that would
6301      /// otherwise be deduced, e.g., we tried to deduce T in "const T"
6302      /// but were given a non-const "X".
6303      TDK_Underqualified,
6304      /// \brief Substitution of the deduced template argument values
6305      /// resulted in an error.
6306      TDK_SubstitutionFailure,
6307      /// \brief A non-depnedent component of the parameter did not match the
6308      /// corresponding component of the argument.
6309      TDK_NonDeducedMismatch,
6310      /// \brief When performing template argument deduction for a function
6311      /// template, there were too many call arguments.
6312      TDK_TooManyArguments,
6313      /// \brief When performing template argument deduction for a function
6314      /// template, there were too few call arguments.
6315      TDK_TooFewArguments,
6316      /// \brief The explicitly-specified template arguments were not valid
6317      /// template arguments for the given template.
6318      TDK_InvalidExplicitArguments,
6319      /// \brief The arguments included an overloaded function name that could
6320      /// not be resolved to a suitable function.
6321      TDK_FailedOverloadResolution,
6322      /// \brief Deduction failed; that's all we know.
6323      TDK_MiscellaneousDeductionFailure
6324    };
6325  
6326    TemplateDeductionResult
6327    DeduceTemplateArguments(ClassTemplatePartialSpecializationDecl *Partial,
6328                            const TemplateArgumentList &TemplateArgs,
6329                            sema::TemplateDeductionInfo &Info);
6330  
6331    TemplateDeductionResult
6332    DeduceTemplateArguments(VarTemplatePartialSpecializationDecl *Partial,
6333                            const TemplateArgumentList &TemplateArgs,
6334                            sema::TemplateDeductionInfo &Info);
6335  
6336    TemplateDeductionResult SubstituteExplicitTemplateArguments(
6337        FunctionTemplateDecl *FunctionTemplate,
6338        TemplateArgumentListInfo &ExplicitTemplateArgs,
6339        SmallVectorImpl<DeducedTemplateArgument> &Deduced,
6340        SmallVectorImpl<QualType> &ParamTypes, QualType *FunctionType,
6341        sema::TemplateDeductionInfo &Info);
6342  
6343    /// brief A function argument from which we performed template argument
6344    // deduction for a call.
6345    struct OriginalCallArg {
OriginalCallArgOriginalCallArg6346      OriginalCallArg(QualType OriginalParamType,
6347                      unsigned ArgIdx,
6348                      QualType OriginalArgType)
6349        : OriginalParamType(OriginalParamType), ArgIdx(ArgIdx),
6350          OriginalArgType(OriginalArgType) { }
6351  
6352      QualType OriginalParamType;
6353      unsigned ArgIdx;
6354      QualType OriginalArgType;
6355    };
6356  
6357    TemplateDeductionResult
6358    FinishTemplateArgumentDeduction(FunctionTemplateDecl *FunctionTemplate,
6359                        SmallVectorImpl<DeducedTemplateArgument> &Deduced,
6360                                    unsigned NumExplicitlySpecified,
6361                                    FunctionDecl *&Specialization,
6362                                    sema::TemplateDeductionInfo &Info,
6363             SmallVectorImpl<OriginalCallArg> const *OriginalCallArgs = nullptr,
6364                                    bool PartialOverloading = false);
6365  
6366    TemplateDeductionResult
6367    DeduceTemplateArguments(FunctionTemplateDecl *FunctionTemplate,
6368                            TemplateArgumentListInfo *ExplicitTemplateArgs,
6369                            ArrayRef<Expr *> Args,
6370                            FunctionDecl *&Specialization,
6371                            sema::TemplateDeductionInfo &Info,
6372                            bool PartialOverloading = false);
6373  
6374    TemplateDeductionResult
6375    DeduceTemplateArguments(FunctionTemplateDecl *FunctionTemplate,
6376                            TemplateArgumentListInfo *ExplicitTemplateArgs,
6377                            QualType ArgFunctionType,
6378                            FunctionDecl *&Specialization,
6379                            sema::TemplateDeductionInfo &Info,
6380                            bool InOverloadResolution = false);
6381  
6382    TemplateDeductionResult
6383    DeduceTemplateArguments(FunctionTemplateDecl *FunctionTemplate,
6384                            QualType ToType,
6385                            CXXConversionDecl *&Specialization,
6386                            sema::TemplateDeductionInfo &Info);
6387  
6388    TemplateDeductionResult
6389    DeduceTemplateArguments(FunctionTemplateDecl *FunctionTemplate,
6390                            TemplateArgumentListInfo *ExplicitTemplateArgs,
6391                            FunctionDecl *&Specialization,
6392                            sema::TemplateDeductionInfo &Info,
6393                            bool InOverloadResolution = false);
6394  
6395    /// \brief Substitute Replacement for \p auto in \p TypeWithAuto
6396    QualType SubstAutoType(QualType TypeWithAuto, QualType Replacement);
6397    /// \brief Substitute Replacement for auto in TypeWithAuto
6398    TypeSourceInfo* SubstAutoTypeSourceInfo(TypeSourceInfo *TypeWithAuto,
6399                                            QualType Replacement);
6400  
6401    /// \brief Result type of DeduceAutoType.
6402    enum DeduceAutoResult {
6403      DAR_Succeeded,
6404      DAR_Failed,
6405      DAR_FailedAlreadyDiagnosed
6406    };
6407  
6408    DeduceAutoResult DeduceAutoType(TypeSourceInfo *AutoType, Expr *&Initializer,
6409                                    QualType &Result);
6410    DeduceAutoResult DeduceAutoType(TypeLoc AutoTypeLoc, Expr *&Initializer,
6411                                    QualType &Result);
6412    void DiagnoseAutoDeductionFailure(VarDecl *VDecl, Expr *Init);
6413    bool DeduceReturnType(FunctionDecl *FD, SourceLocation Loc,
6414                          bool Diagnose = true);
6415  
6416    QualType deduceVarTypeFromInitializer(VarDecl *VDecl, DeclarationName Name,
6417                                          QualType Type, TypeSourceInfo *TSI,
6418                                          SourceRange Range, bool DirectInit,
6419                                          Expr *Init);
6420  
6421    TypeLoc getReturnTypeLoc(FunctionDecl *FD) const;
6422  
6423    bool DeduceFunctionTypeFromReturnExpr(FunctionDecl *FD,
6424                                          SourceLocation ReturnLoc,
6425                                          Expr *&RetExpr, AutoType *AT);
6426  
6427    FunctionTemplateDecl *getMoreSpecializedTemplate(FunctionTemplateDecl *FT1,
6428                                                     FunctionTemplateDecl *FT2,
6429                                                     SourceLocation Loc,
6430                                             TemplatePartialOrderingContext TPOC,
6431                                                     unsigned NumCallArguments1,
6432                                                     unsigned NumCallArguments2);
6433    UnresolvedSetIterator
6434    getMostSpecialized(UnresolvedSetIterator SBegin, UnresolvedSetIterator SEnd,
6435                       TemplateSpecCandidateSet &FailedCandidates,
6436                       SourceLocation Loc,
6437                       const PartialDiagnostic &NoneDiag,
6438                       const PartialDiagnostic &AmbigDiag,
6439                       const PartialDiagnostic &CandidateDiag,
6440                       bool Complain = true, QualType TargetType = QualType());
6441  
6442    ClassTemplatePartialSpecializationDecl *
6443    getMoreSpecializedPartialSpecialization(
6444                                    ClassTemplatePartialSpecializationDecl *PS1,
6445                                    ClassTemplatePartialSpecializationDecl *PS2,
6446                                    SourceLocation Loc);
6447  
6448    VarTemplatePartialSpecializationDecl *getMoreSpecializedPartialSpecialization(
6449        VarTemplatePartialSpecializationDecl *PS1,
6450        VarTemplatePartialSpecializationDecl *PS2, SourceLocation Loc);
6451  
6452    void MarkUsedTemplateParameters(const TemplateArgumentList &TemplateArgs,
6453                                    bool OnlyDeduced,
6454                                    unsigned Depth,
6455                                    llvm::SmallBitVector &Used);
MarkDeducedTemplateParameters(const FunctionTemplateDecl * FunctionTemplate,llvm::SmallBitVector & Deduced)6456    void MarkDeducedTemplateParameters(
6457                                    const FunctionTemplateDecl *FunctionTemplate,
6458                                    llvm::SmallBitVector &Deduced) {
6459      return MarkDeducedTemplateParameters(Context, FunctionTemplate, Deduced);
6460    }
6461    static void MarkDeducedTemplateParameters(ASTContext &Ctx,
6462                                    const FunctionTemplateDecl *FunctionTemplate,
6463                                    llvm::SmallBitVector &Deduced);
6464  
6465    //===--------------------------------------------------------------------===//
6466    // C++ Template Instantiation
6467    //
6468  
6469    MultiLevelTemplateArgumentList
6470    getTemplateInstantiationArgs(NamedDecl *D,
6471                                 const TemplateArgumentList *Innermost = nullptr,
6472                                 bool RelativeToPrimary = false,
6473                                 const FunctionDecl *Pattern = nullptr);
6474  
6475    /// \brief A template instantiation that is currently in progress.
6476    struct ActiveTemplateInstantiation {
6477      /// \brief The kind of template instantiation we are performing
6478      enum InstantiationKind {
6479        /// We are instantiating a template declaration. The entity is
6480        /// the declaration we're instantiating (e.g., a CXXRecordDecl).
6481        TemplateInstantiation,
6482  
6483        /// We are instantiating a default argument for a template
6484        /// parameter. The Entity is the template, and
6485        /// TemplateArgs/NumTemplateArguments provides the template
6486        /// arguments as specified.
6487        /// FIXME: Use a TemplateArgumentList
6488        DefaultTemplateArgumentInstantiation,
6489  
6490        /// We are instantiating a default argument for a function.
6491        /// The Entity is the ParmVarDecl, and TemplateArgs/NumTemplateArgs
6492        /// provides the template arguments as specified.
6493        DefaultFunctionArgumentInstantiation,
6494  
6495        /// We are substituting explicit template arguments provided for
6496        /// a function template. The entity is a FunctionTemplateDecl.
6497        ExplicitTemplateArgumentSubstitution,
6498  
6499        /// We are substituting template argument determined as part of
6500        /// template argument deduction for either a class template
6501        /// partial specialization or a function template. The
6502        /// Entity is either a ClassTemplatePartialSpecializationDecl or
6503        /// a FunctionTemplateDecl.
6504        DeducedTemplateArgumentSubstitution,
6505  
6506        /// We are substituting prior template arguments into a new
6507        /// template parameter. The template parameter itself is either a
6508        /// NonTypeTemplateParmDecl or a TemplateTemplateParmDecl.
6509        PriorTemplateArgumentSubstitution,
6510  
6511        /// We are checking the validity of a default template argument that
6512        /// has been used when naming a template-id.
6513        DefaultTemplateArgumentChecking,
6514  
6515        /// We are instantiating the exception specification for a function
6516        /// template which was deferred until it was needed.
6517        ExceptionSpecInstantiation
6518      } Kind;
6519  
6520      /// \brief The point of instantiation within the source code.
6521      SourceLocation PointOfInstantiation;
6522  
6523      /// \brief The template (or partial specialization) in which we are
6524      /// performing the instantiation, for substitutions of prior template
6525      /// arguments.
6526      NamedDecl *Template;
6527  
6528      /// \brief The entity that is being instantiated.
6529      Decl *Entity;
6530  
6531      /// \brief The list of template arguments we are substituting, if they
6532      /// are not part of the entity.
6533      const TemplateArgument *TemplateArgs;
6534  
6535      /// \brief The number of template arguments in TemplateArgs.
6536      unsigned NumTemplateArgs;
6537  
6538      /// \brief The template deduction info object associated with the
6539      /// substitution or checking of explicit or deduced template arguments.
6540      sema::TemplateDeductionInfo *DeductionInfo;
6541  
6542      /// \brief The source range that covers the construct that cause
6543      /// the instantiation, e.g., the template-id that causes a class
6544      /// template instantiation.
6545      SourceRange InstantiationRange;
6546  
ActiveTemplateInstantiationActiveTemplateInstantiation6547      ActiveTemplateInstantiation()
6548        : Kind(TemplateInstantiation), Template(nullptr), Entity(nullptr),
6549          TemplateArgs(nullptr), NumTemplateArgs(0), DeductionInfo(nullptr) {}
6550  
6551      /// \brief Determines whether this template is an actual instantiation
6552      /// that should be counted toward the maximum instantiation depth.
6553      bool isInstantiationRecord() const;
6554  
6555      friend bool operator==(const ActiveTemplateInstantiation &X,
6556                             const ActiveTemplateInstantiation &Y) {
6557        if (X.Kind != Y.Kind)
6558          return false;
6559  
6560        if (X.Entity != Y.Entity)
6561          return false;
6562  
6563        switch (X.Kind) {
6564        case TemplateInstantiation:
6565        case ExceptionSpecInstantiation:
6566          return true;
6567  
6568        case PriorTemplateArgumentSubstitution:
6569        case DefaultTemplateArgumentChecking:
6570          return X.Template == Y.Template && X.TemplateArgs == Y.TemplateArgs;
6571  
6572        case DefaultTemplateArgumentInstantiation:
6573        case ExplicitTemplateArgumentSubstitution:
6574        case DeducedTemplateArgumentSubstitution:
6575        case DefaultFunctionArgumentInstantiation:
6576          return X.TemplateArgs == Y.TemplateArgs;
6577  
6578        }
6579  
6580        llvm_unreachable("Invalid InstantiationKind!");
6581      }
6582  
6583      friend bool operator!=(const ActiveTemplateInstantiation &X,
6584                             const ActiveTemplateInstantiation &Y) {
6585        return !(X == Y);
6586      }
6587    };
6588  
6589    /// \brief List of active template instantiations.
6590    ///
6591    /// This vector is treated as a stack. As one template instantiation
6592    /// requires another template instantiation, additional
6593    /// instantiations are pushed onto the stack up to a
6594    /// user-configurable limit LangOptions::InstantiationDepth.
6595    SmallVector<ActiveTemplateInstantiation, 16>
6596      ActiveTemplateInstantiations;
6597  
6598    /// \brief Extra modules inspected when performing a lookup during a template
6599    /// instantiation. Computed lazily.
6600    SmallVector<Module*, 16> ActiveTemplateInstantiationLookupModules;
6601  
6602    /// \brief Cache of additional modules that should be used for name lookup
6603    /// within the current template instantiation. Computed lazily; use
6604    /// getLookupModules() to get a complete set.
6605    llvm::DenseSet<Module*> LookupModulesCache;
6606  
6607    /// \brief Get the set of additional modules that should be checked during
6608    /// name lookup. A module and its imports become visible when instanting a
6609    /// template defined within it.
6610    llvm::DenseSet<Module*> &getLookupModules();
6611  
6612    /// \brief Whether we are in a SFINAE context that is not associated with
6613    /// template instantiation.
6614    ///
6615    /// This is used when setting up a SFINAE trap (\c see SFINAETrap) outside
6616    /// of a template instantiation or template argument deduction.
6617    bool InNonInstantiationSFINAEContext;
6618  
6619    /// \brief The number of ActiveTemplateInstantiation entries in
6620    /// \c ActiveTemplateInstantiations that are not actual instantiations and,
6621    /// therefore, should not be counted as part of the instantiation depth.
6622    unsigned NonInstantiationEntries;
6623  
6624    /// \brief The last template from which a template instantiation
6625    /// error or warning was produced.
6626    ///
6627    /// This value is used to suppress printing of redundant template
6628    /// instantiation backtraces when there are multiple errors in the
6629    /// same instantiation. FIXME: Does this belong in Sema? It's tough
6630    /// to implement it anywhere else.
6631    ActiveTemplateInstantiation LastTemplateInstantiationErrorContext;
6632  
6633    /// \brief The current index into pack expansion arguments that will be
6634    /// used for substitution of parameter packs.
6635    ///
6636    /// The pack expansion index will be -1 to indicate that parameter packs
6637    /// should be instantiated as themselves. Otherwise, the index specifies
6638    /// which argument within the parameter pack will be used for substitution.
6639    int ArgumentPackSubstitutionIndex;
6640  
6641    /// \brief RAII object used to change the argument pack substitution index
6642    /// within a \c Sema object.
6643    ///
6644    /// See \c ArgumentPackSubstitutionIndex for more information.
6645    class ArgumentPackSubstitutionIndexRAII {
6646      Sema &Self;
6647      int OldSubstitutionIndex;
6648  
6649    public:
ArgumentPackSubstitutionIndexRAII(Sema & Self,int NewSubstitutionIndex)6650      ArgumentPackSubstitutionIndexRAII(Sema &Self, int NewSubstitutionIndex)
6651        : Self(Self), OldSubstitutionIndex(Self.ArgumentPackSubstitutionIndex) {
6652        Self.ArgumentPackSubstitutionIndex = NewSubstitutionIndex;
6653      }
6654  
~ArgumentPackSubstitutionIndexRAII()6655      ~ArgumentPackSubstitutionIndexRAII() {
6656        Self.ArgumentPackSubstitutionIndex = OldSubstitutionIndex;
6657      }
6658    };
6659  
6660    friend class ArgumentPackSubstitutionRAII;
6661  
6662    /// \brief For each declaration that involved template argument deduction, the
6663    /// set of diagnostics that were suppressed during that template argument
6664    /// deduction.
6665    ///
6666    /// FIXME: Serialize this structure to the AST file.
6667    typedef llvm::DenseMap<Decl *, SmallVector<PartialDiagnosticAt, 1> >
6668      SuppressedDiagnosticsMap;
6669    SuppressedDiagnosticsMap SuppressedDiagnostics;
6670  
6671    /// \brief A stack object to be created when performing template
6672    /// instantiation.
6673    ///
6674    /// Construction of an object of type \c InstantiatingTemplate
6675    /// pushes the current instantiation onto the stack of active
6676    /// instantiations. If the size of this stack exceeds the maximum
6677    /// number of recursive template instantiations, construction
6678    /// produces an error and evaluates true.
6679    ///
6680    /// Destruction of this object will pop the named instantiation off
6681    /// the stack.
6682    struct InstantiatingTemplate {
6683      /// \brief Note that we are instantiating a class template,
6684      /// function template, variable template, alias template,
6685      /// or a member thereof.
6686      InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
6687                            Decl *Entity,
6688                            SourceRange InstantiationRange = SourceRange());
6689  
6690      struct ExceptionSpecification {};
6691      /// \brief Note that we are instantiating an exception specification
6692      /// of a function template.
6693      InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
6694                            FunctionDecl *Entity, ExceptionSpecification,
6695                            SourceRange InstantiationRange = SourceRange());
6696  
6697      /// \brief Note that we are instantiating a default argument in a
6698      /// template-id.
6699      InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
6700                            TemplateDecl *Template,
6701                            ArrayRef<TemplateArgument> TemplateArgs,
6702                            SourceRange InstantiationRange = SourceRange());
6703  
6704      /// \brief Note that we are instantiating a default argument in a
6705      /// template-id.
6706      InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
6707                            FunctionTemplateDecl *FunctionTemplate,
6708                            ArrayRef<TemplateArgument> TemplateArgs,
6709                            ActiveTemplateInstantiation::InstantiationKind Kind,
6710                            sema::TemplateDeductionInfo &DeductionInfo,
6711                            SourceRange InstantiationRange = SourceRange());
6712  
6713      /// \brief Note that we are instantiating as part of template
6714      /// argument deduction for a class template partial
6715      /// specialization.
6716      InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
6717                            ClassTemplatePartialSpecializationDecl *PartialSpec,
6718                            ArrayRef<TemplateArgument> TemplateArgs,
6719                            sema::TemplateDeductionInfo &DeductionInfo,
6720                            SourceRange InstantiationRange = SourceRange());
6721  
6722      /// \brief Note that we are instantiating as part of template
6723      /// argument deduction for a variable template partial
6724      /// specialization.
6725      InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
6726                            VarTemplatePartialSpecializationDecl *PartialSpec,
6727                            ArrayRef<TemplateArgument> TemplateArgs,
6728                            sema::TemplateDeductionInfo &DeductionInfo,
6729                            SourceRange InstantiationRange = SourceRange());
6730  
6731      /// \brief Note that we are instantiating a default argument for a function
6732      /// parameter.
6733      InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
6734                            ParmVarDecl *Param,
6735                            ArrayRef<TemplateArgument> TemplateArgs,
6736                            SourceRange InstantiationRange = SourceRange());
6737  
6738      /// \brief Note that we are substituting prior template arguments into a
6739      /// non-type parameter.
6740      InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
6741                            NamedDecl *Template,
6742                            NonTypeTemplateParmDecl *Param,
6743                            ArrayRef<TemplateArgument> TemplateArgs,
6744                            SourceRange InstantiationRange);
6745  
6746      /// \brief Note that we are substituting prior template arguments into a
6747      /// template template parameter.
6748      InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
6749                            NamedDecl *Template,
6750                            TemplateTemplateParmDecl *Param,
6751                            ArrayRef<TemplateArgument> TemplateArgs,
6752                            SourceRange InstantiationRange);
6753  
6754      /// \brief Note that we are checking the default template argument
6755      /// against the template parameter for a given template-id.
6756      InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
6757                            TemplateDecl *Template,
6758                            NamedDecl *Param,
6759                            ArrayRef<TemplateArgument> TemplateArgs,
6760                            SourceRange InstantiationRange);
6761  
6762  
6763      /// \brief Note that we have finished instantiating this template.
6764      void Clear();
6765  
~InstantiatingTemplateInstantiatingTemplate6766      ~InstantiatingTemplate() { Clear(); }
6767  
6768      /// \brief Determines whether we have exceeded the maximum
6769      /// recursive template instantiations.
isInvalidInstantiatingTemplate6770      bool isInvalid() const { return Invalid; }
6771  
6772    private:
6773      Sema &SemaRef;
6774      bool Invalid;
6775      bool SavedInNonInstantiationSFINAEContext;
6776      bool CheckInstantiationDepth(SourceLocation PointOfInstantiation,
6777                                   SourceRange InstantiationRange);
6778  
6779      InstantiatingTemplate(
6780          Sema &SemaRef, ActiveTemplateInstantiation::InstantiationKind Kind,
6781          SourceLocation PointOfInstantiation, SourceRange InstantiationRange,
6782          Decl *Entity, NamedDecl *Template = nullptr,
6783          ArrayRef<TemplateArgument> TemplateArgs = None,
6784          sema::TemplateDeductionInfo *DeductionInfo = nullptr);
6785  
6786      InstantiatingTemplate(const InstantiatingTemplate&) = delete;
6787  
6788      InstantiatingTemplate&
6789      operator=(const InstantiatingTemplate&) = delete;
6790    };
6791  
6792    void PrintInstantiationStack();
6793  
6794    /// \brief Determines whether we are currently in a context where
6795    /// template argument substitution failures are not considered
6796    /// errors.
6797    ///
6798    /// \returns An empty \c Optional if we're not in a SFINAE context.
6799    /// Otherwise, contains a pointer that, if non-NULL, contains the nearest
6800    /// template-deduction context object, which can be used to capture
6801    /// diagnostics that will be suppressed.
6802    Optional<sema::TemplateDeductionInfo *> isSFINAEContext() const;
6803  
6804    /// \brief Determines whether we are currently in a context that
6805    /// is not evaluated as per C++ [expr] p5.
isUnevaluatedContext()6806    bool isUnevaluatedContext() const {
6807      assert(!ExprEvalContexts.empty() &&
6808             "Must be in an expression evaluation context");
6809      return ExprEvalContexts.back().isUnevaluated();
6810    }
6811  
6812    /// \brief RAII class used to determine whether SFINAE has
6813    /// trapped any errors that occur during template argument
6814    /// deduction.
6815    class SFINAETrap {
6816      Sema &SemaRef;
6817      unsigned PrevSFINAEErrors;
6818      bool PrevInNonInstantiationSFINAEContext;
6819      bool PrevAccessCheckingSFINAE;
6820  
6821    public:
6822      explicit SFINAETrap(Sema &SemaRef, bool AccessCheckingSFINAE = false)
SemaRef(SemaRef)6823        : SemaRef(SemaRef), PrevSFINAEErrors(SemaRef.NumSFINAEErrors),
6824          PrevInNonInstantiationSFINAEContext(
6825                                        SemaRef.InNonInstantiationSFINAEContext),
6826          PrevAccessCheckingSFINAE(SemaRef.AccessCheckingSFINAE)
6827      {
6828        if (!SemaRef.isSFINAEContext())
6829          SemaRef.InNonInstantiationSFINAEContext = true;
6830        SemaRef.AccessCheckingSFINAE = AccessCheckingSFINAE;
6831      }
6832  
~SFINAETrap()6833      ~SFINAETrap() {
6834        SemaRef.NumSFINAEErrors = PrevSFINAEErrors;
6835        SemaRef.InNonInstantiationSFINAEContext
6836          = PrevInNonInstantiationSFINAEContext;
6837        SemaRef.AccessCheckingSFINAE = PrevAccessCheckingSFINAE;
6838      }
6839  
6840      /// \brief Determine whether any SFINAE errors have been trapped.
hasErrorOccurred()6841      bool hasErrorOccurred() const {
6842        return SemaRef.NumSFINAEErrors > PrevSFINAEErrors;
6843      }
6844    };
6845  
6846    /// \brief RAII class used to indicate that we are performing provisional
6847    /// semantic analysis to determine the validity of a construct, so
6848    /// typo-correction and diagnostics in the immediate context (not within
6849    /// implicitly-instantiated templates) should be suppressed.
6850    class TentativeAnalysisScope {
6851      Sema &SemaRef;
6852      // FIXME: Using a SFINAETrap for this is a hack.
6853      SFINAETrap Trap;
6854      bool PrevDisableTypoCorrection;
6855    public:
TentativeAnalysisScope(Sema & SemaRef)6856      explicit TentativeAnalysisScope(Sema &SemaRef)
6857          : SemaRef(SemaRef), Trap(SemaRef, true),
6858            PrevDisableTypoCorrection(SemaRef.DisableTypoCorrection) {
6859        SemaRef.DisableTypoCorrection = true;
6860      }
~TentativeAnalysisScope()6861      ~TentativeAnalysisScope() {
6862        SemaRef.DisableTypoCorrection = PrevDisableTypoCorrection;
6863      }
6864    };
6865  
6866    /// \brief The current instantiation scope used to store local
6867    /// variables.
6868    LocalInstantiationScope *CurrentInstantiationScope;
6869  
6870    /// \brief Tracks whether we are in a context where typo correction is
6871    /// disabled.
6872    bool DisableTypoCorrection;
6873  
6874    /// \brief The number of typos corrected by CorrectTypo.
6875    unsigned TyposCorrected;
6876  
6877    typedef llvm::SmallSet<SourceLocation, 2> SrcLocSet;
6878    typedef llvm::DenseMap<IdentifierInfo *, SrcLocSet> IdentifierSourceLocations;
6879  
6880    /// \brief A cache containing identifiers for which typo correction failed and
6881    /// their locations, so that repeated attempts to correct an identifier in a
6882    /// given location are ignored if typo correction already failed for it.
6883    IdentifierSourceLocations TypoCorrectionFailures;
6884  
6885    /// \brief Worker object for performing CFG-based warnings.
6886    sema::AnalysisBasedWarnings AnalysisWarnings;
6887    threadSafety::BeforeSet *ThreadSafetyDeclCache;
6888  
6889    /// \brief An entity for which implicit template instantiation is required.
6890    ///
6891    /// The source location associated with the declaration is the first place in
6892    /// the source code where the declaration was "used". It is not necessarily
6893    /// the point of instantiation (which will be either before or after the
6894    /// namespace-scope declaration that triggered this implicit instantiation),
6895    /// However, it is the location that diagnostics should generally refer to,
6896    /// because users will need to know what code triggered the instantiation.
6897    typedef std::pair<ValueDecl *, SourceLocation> PendingImplicitInstantiation;
6898  
6899    /// \brief The queue of implicit template instantiations that are required
6900    /// but have not yet been performed.
6901    std::deque<PendingImplicitInstantiation> PendingInstantiations;
6902  
6903    class SavePendingInstantiationsAndVTableUsesRAII {
6904    public:
SavePendingInstantiationsAndVTableUsesRAII(Sema & S,bool Enabled)6905      SavePendingInstantiationsAndVTableUsesRAII(Sema &S, bool Enabled)
6906          : S(S), Enabled(Enabled) {
6907        if (!Enabled) return;
6908  
6909        SavedPendingInstantiations.swap(S.PendingInstantiations);
6910        SavedVTableUses.swap(S.VTableUses);
6911      }
6912  
~SavePendingInstantiationsAndVTableUsesRAII()6913      ~SavePendingInstantiationsAndVTableUsesRAII() {
6914        if (!Enabled) return;
6915  
6916        // Restore the set of pending vtables.
6917        assert(S.VTableUses.empty() &&
6918               "VTableUses should be empty before it is discarded.");
6919        S.VTableUses.swap(SavedVTableUses);
6920  
6921        // Restore the set of pending implicit instantiations.
6922        assert(S.PendingInstantiations.empty() &&
6923               "PendingInstantiations should be empty before it is discarded.");
6924        S.PendingInstantiations.swap(SavedPendingInstantiations);
6925      }
6926  
6927    private:
6928      Sema &S;
6929      SmallVector<VTableUse, 16> SavedVTableUses;
6930      std::deque<PendingImplicitInstantiation> SavedPendingInstantiations;
6931      bool Enabled;
6932    };
6933  
6934    /// \brief The queue of implicit template instantiations that are required
6935    /// and must be performed within the current local scope.
6936    ///
6937    /// This queue is only used for member functions of local classes in
6938    /// templates, which must be instantiated in the same scope as their
6939    /// enclosing function, so that they can reference function-local
6940    /// types, static variables, enumerators, etc.
6941    std::deque<PendingImplicitInstantiation> PendingLocalImplicitInstantiations;
6942  
6943    class SavePendingLocalImplicitInstantiationsRAII {
6944    public:
SavePendingLocalImplicitInstantiationsRAII(Sema & S)6945      SavePendingLocalImplicitInstantiationsRAII(Sema &S): S(S) {
6946        SavedPendingLocalImplicitInstantiations.swap(
6947            S.PendingLocalImplicitInstantiations);
6948      }
6949  
~SavePendingLocalImplicitInstantiationsRAII()6950      ~SavePendingLocalImplicitInstantiationsRAII() {
6951        assert(S.PendingLocalImplicitInstantiations.empty() &&
6952               "there shouldn't be any pending local implicit instantiations");
6953        SavedPendingLocalImplicitInstantiations.swap(
6954            S.PendingLocalImplicitInstantiations);
6955      }
6956  
6957    private:
6958      Sema &S;
6959      std::deque<PendingImplicitInstantiation>
6960      SavedPendingLocalImplicitInstantiations;
6961    };
6962  
6963    void PerformPendingInstantiations(bool LocalOnly = false);
6964  
6965    TypeSourceInfo *SubstType(TypeSourceInfo *T,
6966                              const MultiLevelTemplateArgumentList &TemplateArgs,
6967                              SourceLocation Loc, DeclarationName Entity);
6968  
6969    QualType SubstType(QualType T,
6970                       const MultiLevelTemplateArgumentList &TemplateArgs,
6971                       SourceLocation Loc, DeclarationName Entity);
6972  
6973    TypeSourceInfo *SubstType(TypeLoc TL,
6974                              const MultiLevelTemplateArgumentList &TemplateArgs,
6975                              SourceLocation Loc, DeclarationName Entity);
6976  
6977    TypeSourceInfo *SubstFunctionDeclType(TypeSourceInfo *T,
6978                              const MultiLevelTemplateArgumentList &TemplateArgs,
6979                                          SourceLocation Loc,
6980                                          DeclarationName Entity,
6981                                          CXXRecordDecl *ThisContext,
6982                                          unsigned ThisTypeQuals);
6983    void SubstExceptionSpec(FunctionDecl *New, const FunctionProtoType *Proto,
6984                            const MultiLevelTemplateArgumentList &Args);
6985    ParmVarDecl *SubstParmVarDecl(ParmVarDecl *D,
6986                              const MultiLevelTemplateArgumentList &TemplateArgs,
6987                                  int indexAdjustment,
6988                                  Optional<unsigned> NumExpansions,
6989                                  bool ExpectParameterPack);
6990    bool SubstParmTypes(SourceLocation Loc,
6991                        ParmVarDecl **Params, unsigned NumParams,
6992                        const MultiLevelTemplateArgumentList &TemplateArgs,
6993                        SmallVectorImpl<QualType> &ParamTypes,
6994                        SmallVectorImpl<ParmVarDecl *> *OutParams = nullptr);
6995    ExprResult SubstExpr(Expr *E,
6996                         const MultiLevelTemplateArgumentList &TemplateArgs);
6997  
6998    /// \brief Substitute the given template arguments into a list of
6999    /// expressions, expanding pack expansions if required.
7000    ///
7001    /// \param Exprs The list of expressions to substitute into.
7002    ///
7003    /// \param NumExprs The number of expressions in \p Exprs.
7004    ///
7005    /// \param IsCall Whether this is some form of call, in which case
7006    /// default arguments will be dropped.
7007    ///
7008    /// \param TemplateArgs The set of template arguments to substitute.
7009    ///
7010    /// \param Outputs Will receive all of the substituted arguments.
7011    ///
7012    /// \returns true if an error occurred, false otherwise.
7013    bool SubstExprs(Expr **Exprs, unsigned NumExprs, bool IsCall,
7014                    const MultiLevelTemplateArgumentList &TemplateArgs,
7015                    SmallVectorImpl<Expr *> &Outputs);
7016  
7017    StmtResult SubstStmt(Stmt *S,
7018                         const MultiLevelTemplateArgumentList &TemplateArgs);
7019  
7020    Decl *SubstDecl(Decl *D, DeclContext *Owner,
7021                    const MultiLevelTemplateArgumentList &TemplateArgs);
7022  
7023    ExprResult SubstInitializer(Expr *E,
7024                         const MultiLevelTemplateArgumentList &TemplateArgs,
7025                         bool CXXDirectInit);
7026  
7027    bool
7028    SubstBaseSpecifiers(CXXRecordDecl *Instantiation,
7029                        CXXRecordDecl *Pattern,
7030                        const MultiLevelTemplateArgumentList &TemplateArgs);
7031  
7032    bool
7033    InstantiateClass(SourceLocation PointOfInstantiation,
7034                     CXXRecordDecl *Instantiation, CXXRecordDecl *Pattern,
7035                     const MultiLevelTemplateArgumentList &TemplateArgs,
7036                     TemplateSpecializationKind TSK,
7037                     bool Complain = true);
7038  
7039    bool InstantiateEnum(SourceLocation PointOfInstantiation,
7040                         EnumDecl *Instantiation, EnumDecl *Pattern,
7041                         const MultiLevelTemplateArgumentList &TemplateArgs,
7042                         TemplateSpecializationKind TSK);
7043  
7044    bool InstantiateInClassInitializer(
7045        SourceLocation PointOfInstantiation, FieldDecl *Instantiation,
7046        FieldDecl *Pattern, const MultiLevelTemplateArgumentList &TemplateArgs);
7047  
7048    struct LateInstantiatedAttribute {
7049      const Attr *TmplAttr;
7050      LocalInstantiationScope *Scope;
7051      Decl *NewDecl;
7052  
LateInstantiatedAttributeLateInstantiatedAttribute7053      LateInstantiatedAttribute(const Attr *A, LocalInstantiationScope *S,
7054                                Decl *D)
7055        : TmplAttr(A), Scope(S), NewDecl(D)
7056      { }
7057    };
7058    typedef SmallVector<LateInstantiatedAttribute, 16> LateInstantiatedAttrVec;
7059  
7060    void InstantiateAttrs(const MultiLevelTemplateArgumentList &TemplateArgs,
7061                          const Decl *Pattern, Decl *Inst,
7062                          LateInstantiatedAttrVec *LateAttrs = nullptr,
7063                          LocalInstantiationScope *OuterMostScope = nullptr);
7064  
7065    bool
7066    InstantiateClassTemplateSpecialization(SourceLocation PointOfInstantiation,
7067                             ClassTemplateSpecializationDecl *ClassTemplateSpec,
7068                             TemplateSpecializationKind TSK,
7069                             bool Complain = true);
7070  
7071    void InstantiateClassMembers(SourceLocation PointOfInstantiation,
7072                                 CXXRecordDecl *Instantiation,
7073                              const MultiLevelTemplateArgumentList &TemplateArgs,
7074                                 TemplateSpecializationKind TSK);
7075  
7076    void InstantiateClassTemplateSpecializationMembers(
7077                                            SourceLocation PointOfInstantiation,
7078                             ClassTemplateSpecializationDecl *ClassTemplateSpec,
7079                                                  TemplateSpecializationKind TSK);
7080  
7081    NestedNameSpecifierLoc
7082    SubstNestedNameSpecifierLoc(NestedNameSpecifierLoc NNS,
7083                             const MultiLevelTemplateArgumentList &TemplateArgs);
7084  
7085    DeclarationNameInfo
7086    SubstDeclarationNameInfo(const DeclarationNameInfo &NameInfo,
7087                             const MultiLevelTemplateArgumentList &TemplateArgs);
7088    TemplateName
7089    SubstTemplateName(NestedNameSpecifierLoc QualifierLoc, TemplateName Name,
7090                      SourceLocation Loc,
7091                      const MultiLevelTemplateArgumentList &TemplateArgs);
7092    bool Subst(const TemplateArgumentLoc *Args, unsigned NumArgs,
7093               TemplateArgumentListInfo &Result,
7094               const MultiLevelTemplateArgumentList &TemplateArgs);
7095  
7096    void InstantiateExceptionSpec(SourceLocation PointOfInstantiation,
7097                                  FunctionDecl *Function);
7098    void InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
7099                                       FunctionDecl *Function,
7100                                       bool Recursive = false,
7101                                       bool DefinitionRequired = false);
7102    VarTemplateSpecializationDecl *BuildVarTemplateInstantiation(
7103        VarTemplateDecl *VarTemplate, VarDecl *FromVar,
7104        const TemplateArgumentList &TemplateArgList,
7105        const TemplateArgumentListInfo &TemplateArgsInfo,
7106        SmallVectorImpl<TemplateArgument> &Converted,
7107        SourceLocation PointOfInstantiation, void *InsertPos,
7108        LateInstantiatedAttrVec *LateAttrs = nullptr,
7109        LocalInstantiationScope *StartingScope = nullptr);
7110    VarTemplateSpecializationDecl *CompleteVarTemplateSpecializationDecl(
7111        VarTemplateSpecializationDecl *VarSpec, VarDecl *PatternDecl,
7112        const MultiLevelTemplateArgumentList &TemplateArgs);
7113    void
7114    BuildVariableInstantiation(VarDecl *NewVar, VarDecl *OldVar,
7115                               const MultiLevelTemplateArgumentList &TemplateArgs,
7116                               LateInstantiatedAttrVec *LateAttrs,
7117                               DeclContext *Owner,
7118                               LocalInstantiationScope *StartingScope,
7119                               bool InstantiatingVarTemplate = false);
7120    void InstantiateVariableInitializer(
7121        VarDecl *Var, VarDecl *OldVar,
7122        const MultiLevelTemplateArgumentList &TemplateArgs);
7123    void InstantiateVariableDefinition(SourceLocation PointOfInstantiation,
7124                                       VarDecl *Var, bool Recursive = false,
7125                                       bool DefinitionRequired = false);
7126    void InstantiateStaticDataMemberDefinition(
7127                                       SourceLocation PointOfInstantiation,
7128                                       VarDecl *Var,
7129                                       bool Recursive = false,
7130                                       bool DefinitionRequired = false);
7131  
7132    void InstantiateMemInitializers(CXXConstructorDecl *New,
7133                                    const CXXConstructorDecl *Tmpl,
7134                              const MultiLevelTemplateArgumentList &TemplateArgs);
7135  
7136    NamedDecl *FindInstantiatedDecl(SourceLocation Loc, NamedDecl *D,
7137                            const MultiLevelTemplateArgumentList &TemplateArgs);
7138    DeclContext *FindInstantiatedContext(SourceLocation Loc, DeclContext *DC,
7139                            const MultiLevelTemplateArgumentList &TemplateArgs);
7140  
7141    // Objective-C declarations.
7142    enum ObjCContainerKind {
7143      OCK_None = -1,
7144      OCK_Interface = 0,
7145      OCK_Protocol,
7146      OCK_Category,
7147      OCK_ClassExtension,
7148      OCK_Implementation,
7149      OCK_CategoryImplementation
7150    };
7151    ObjCContainerKind getObjCContainerKind() const;
7152  
7153    DeclResult actOnObjCTypeParam(Scope *S,
7154                                  ObjCTypeParamVariance variance,
7155                                  SourceLocation varianceLoc,
7156                                  unsigned index,
7157                                  IdentifierInfo *paramName,
7158                                  SourceLocation paramLoc,
7159                                  SourceLocation colonLoc,
7160                                  ParsedType typeBound);
7161  
7162    ObjCTypeParamList *actOnObjCTypeParamList(Scope *S, SourceLocation lAngleLoc,
7163                                              ArrayRef<Decl *> typeParams,
7164                                              SourceLocation rAngleLoc);
7165    void popObjCTypeParamList(Scope *S, ObjCTypeParamList *typeParamList);
7166  
7167    Decl *ActOnStartClassInterface(Scope *S,
7168                                   SourceLocation AtInterfaceLoc,
7169                                   IdentifierInfo *ClassName,
7170                                   SourceLocation ClassLoc,
7171                                   ObjCTypeParamList *typeParamList,
7172                                   IdentifierInfo *SuperName,
7173                                   SourceLocation SuperLoc,
7174                                   ArrayRef<ParsedType> SuperTypeArgs,
7175                                   SourceRange SuperTypeArgsRange,
7176                                   Decl * const *ProtoRefs,
7177                                   unsigned NumProtoRefs,
7178                                   const SourceLocation *ProtoLocs,
7179                                   SourceLocation EndProtoLoc,
7180                                   AttributeList *AttrList);
7181  
7182    void ActOnSuperClassOfClassInterface(Scope *S,
7183                                         SourceLocation AtInterfaceLoc,
7184                                         ObjCInterfaceDecl *IDecl,
7185                                         IdentifierInfo *ClassName,
7186                                         SourceLocation ClassLoc,
7187                                         IdentifierInfo *SuperName,
7188                                         SourceLocation SuperLoc,
7189                                         ArrayRef<ParsedType> SuperTypeArgs,
7190                                         SourceRange SuperTypeArgsRange);
7191  
7192    void ActOnTypedefedProtocols(SmallVectorImpl<Decl *> &ProtocolRefs,
7193                                 IdentifierInfo *SuperName,
7194                                 SourceLocation SuperLoc);
7195  
7196    Decl *ActOnCompatibilityAlias(
7197                      SourceLocation AtCompatibilityAliasLoc,
7198                      IdentifierInfo *AliasName,  SourceLocation AliasLocation,
7199                      IdentifierInfo *ClassName, SourceLocation ClassLocation);
7200  
7201    bool CheckForwardProtocolDeclarationForCircularDependency(
7202      IdentifierInfo *PName,
7203      SourceLocation &PLoc, SourceLocation PrevLoc,
7204      const ObjCList<ObjCProtocolDecl> &PList);
7205  
7206    Decl *ActOnStartProtocolInterface(
7207                      SourceLocation AtProtoInterfaceLoc,
7208                      IdentifierInfo *ProtocolName, SourceLocation ProtocolLoc,
7209                      Decl * const *ProtoRefNames, unsigned NumProtoRefs,
7210                      const SourceLocation *ProtoLocs,
7211                      SourceLocation EndProtoLoc,
7212                      AttributeList *AttrList);
7213  
7214    Decl *ActOnStartCategoryInterface(SourceLocation AtInterfaceLoc,
7215                                      IdentifierInfo *ClassName,
7216                                      SourceLocation ClassLoc,
7217                                      ObjCTypeParamList *typeParamList,
7218                                      IdentifierInfo *CategoryName,
7219                                      SourceLocation CategoryLoc,
7220                                      Decl * const *ProtoRefs,
7221                                      unsigned NumProtoRefs,
7222                                      const SourceLocation *ProtoLocs,
7223                                      SourceLocation EndProtoLoc);
7224  
7225    Decl *ActOnStartClassImplementation(
7226                      SourceLocation AtClassImplLoc,
7227                      IdentifierInfo *ClassName, SourceLocation ClassLoc,
7228                      IdentifierInfo *SuperClassname,
7229                      SourceLocation SuperClassLoc);
7230  
7231    Decl *ActOnStartCategoryImplementation(SourceLocation AtCatImplLoc,
7232                                           IdentifierInfo *ClassName,
7233                                           SourceLocation ClassLoc,
7234                                           IdentifierInfo *CatName,
7235                                           SourceLocation CatLoc);
7236  
7237    DeclGroupPtrTy ActOnFinishObjCImplementation(Decl *ObjCImpDecl,
7238                                                 ArrayRef<Decl *> Decls);
7239  
7240    DeclGroupPtrTy ActOnForwardClassDeclaration(SourceLocation Loc,
7241                     IdentifierInfo **IdentList,
7242                     SourceLocation *IdentLocs,
7243                     ArrayRef<ObjCTypeParamList *> TypeParamLists,
7244                     unsigned NumElts);
7245  
7246    DeclGroupPtrTy ActOnForwardProtocolDeclaration(SourceLocation AtProtoclLoc,
7247                                          ArrayRef<IdentifierLocPair> IdentList,
7248                                          AttributeList *attrList);
7249  
7250    void FindProtocolDeclaration(bool WarnOnDeclarations, bool ForObjCContainer,
7251                                 ArrayRef<IdentifierLocPair> ProtocolId,
7252                                 SmallVectorImpl<Decl *> &Protocols);
7253  
7254    /// Given a list of identifiers (and their locations), resolve the
7255    /// names to either Objective-C protocol qualifiers or type
7256    /// arguments, as appropriate.
7257    void actOnObjCTypeArgsOrProtocolQualifiers(
7258           Scope *S,
7259           ParsedType baseType,
7260           SourceLocation lAngleLoc,
7261           ArrayRef<IdentifierInfo *> identifiers,
7262           ArrayRef<SourceLocation> identifierLocs,
7263           SourceLocation rAngleLoc,
7264           SourceLocation &typeArgsLAngleLoc,
7265           SmallVectorImpl<ParsedType> &typeArgs,
7266           SourceLocation &typeArgsRAngleLoc,
7267           SourceLocation &protocolLAngleLoc,
7268           SmallVectorImpl<Decl *> &protocols,
7269           SourceLocation &protocolRAngleLoc,
7270           bool warnOnIncompleteProtocols);
7271  
7272    /// Build a an Objective-C protocol-qualified 'id' type where no
7273    /// base type was specified.
7274    TypeResult actOnObjCProtocolQualifierType(
7275                 SourceLocation lAngleLoc,
7276                 ArrayRef<Decl *> protocols,
7277                 ArrayRef<SourceLocation> protocolLocs,
7278                 SourceLocation rAngleLoc);
7279  
7280    /// Build a specialized and/or protocol-qualified Objective-C type.
7281    TypeResult actOnObjCTypeArgsAndProtocolQualifiers(
7282                 Scope *S,
7283                 SourceLocation Loc,
7284                 ParsedType BaseType,
7285                 SourceLocation TypeArgsLAngleLoc,
7286                 ArrayRef<ParsedType> TypeArgs,
7287                 SourceLocation TypeArgsRAngleLoc,
7288                 SourceLocation ProtocolLAngleLoc,
7289                 ArrayRef<Decl *> Protocols,
7290                 ArrayRef<SourceLocation> ProtocolLocs,
7291                 SourceLocation ProtocolRAngleLoc);
7292  
7293    /// Build an Objective-C object pointer type.
7294    QualType BuildObjCObjectType(QualType BaseType,
7295                                 SourceLocation Loc,
7296                                 SourceLocation TypeArgsLAngleLoc,
7297                                 ArrayRef<TypeSourceInfo *> TypeArgs,
7298                                 SourceLocation TypeArgsRAngleLoc,
7299                                 SourceLocation ProtocolLAngleLoc,
7300                                 ArrayRef<ObjCProtocolDecl *> Protocols,
7301                                 ArrayRef<SourceLocation> ProtocolLocs,
7302                                 SourceLocation ProtocolRAngleLoc,
7303                                 bool FailOnError = false);
7304  
7305    /// Check the application of the Objective-C '__kindof' qualifier to
7306    /// the given type.
7307    bool checkObjCKindOfType(QualType &type, SourceLocation loc);
7308  
7309    /// Ensure attributes are consistent with type.
7310    /// \param [in, out] Attributes The attributes to check; they will
7311    /// be modified to be consistent with \p PropertyTy.
7312    void CheckObjCPropertyAttributes(Decl *PropertyPtrTy,
7313                                     SourceLocation Loc,
7314                                     unsigned &Attributes,
7315                                     bool propertyInPrimaryClass);
7316  
7317    /// Process the specified property declaration and create decls for the
7318    /// setters and getters as needed.
7319    /// \param property The property declaration being processed
7320    void ProcessPropertyDecl(ObjCPropertyDecl *property);
7321  
7322  
7323    void DiagnosePropertyMismatch(ObjCPropertyDecl *Property,
7324                                  ObjCPropertyDecl *SuperProperty,
7325                                  const IdentifierInfo *Name,
7326                                  bool OverridingProtocolProperty);
7327  
7328    void DiagnoseClassExtensionDupMethods(ObjCCategoryDecl *CAT,
7329                                          ObjCInterfaceDecl *ID);
7330  
7331    Decl *ActOnAtEnd(Scope *S, SourceRange AtEnd,
7332                     ArrayRef<Decl *> allMethods = None,
7333                     ArrayRef<DeclGroupPtrTy> allTUVars = None);
7334  
7335    Decl *ActOnProperty(Scope *S, SourceLocation AtLoc,
7336                        SourceLocation LParenLoc,
7337                        FieldDeclarator &FD, ObjCDeclSpec &ODS,
7338                        Selector GetterSel, Selector SetterSel,
7339                        tok::ObjCKeywordKind MethodImplKind,
7340                        DeclContext *lexicalDC = nullptr);
7341  
7342    Decl *ActOnPropertyImplDecl(Scope *S,
7343                                SourceLocation AtLoc,
7344                                SourceLocation PropertyLoc,
7345                                bool ImplKind,
7346                                IdentifierInfo *PropertyId,
7347                                IdentifierInfo *PropertyIvar,
7348                                SourceLocation PropertyIvarLoc);
7349  
7350    enum ObjCSpecialMethodKind {
7351      OSMK_None,
7352      OSMK_Alloc,
7353      OSMK_New,
7354      OSMK_Copy,
7355      OSMK_RetainingInit,
7356      OSMK_NonRetainingInit
7357    };
7358  
7359    struct ObjCArgInfo {
7360      IdentifierInfo *Name;
7361      SourceLocation NameLoc;
7362      // The Type is null if no type was specified, and the DeclSpec is invalid
7363      // in this case.
7364      ParsedType Type;
7365      ObjCDeclSpec DeclSpec;
7366  
7367      /// ArgAttrs - Attribute list for this argument.
7368      AttributeList *ArgAttrs;
7369    };
7370  
7371    Decl *ActOnMethodDeclaration(
7372      Scope *S,
7373      SourceLocation BeginLoc, // location of the + or -.
7374      SourceLocation EndLoc,   // location of the ; or {.
7375      tok::TokenKind MethodType,
7376      ObjCDeclSpec &ReturnQT, ParsedType ReturnType,
7377      ArrayRef<SourceLocation> SelectorLocs, Selector Sel,
7378      // optional arguments. The number of types/arguments is obtained
7379      // from the Sel.getNumArgs().
7380      ObjCArgInfo *ArgInfo,
7381      DeclaratorChunk::ParamInfo *CParamInfo, unsigned CNumArgs, // c-style args
7382      AttributeList *AttrList, tok::ObjCKeywordKind MethodImplKind,
7383      bool isVariadic, bool MethodDefinition);
7384  
7385    ObjCMethodDecl *LookupMethodInQualifiedType(Selector Sel,
7386                                                const ObjCObjectPointerType *OPT,
7387                                                bool IsInstance);
7388    ObjCMethodDecl *LookupMethodInObjectType(Selector Sel, QualType Ty,
7389                                             bool IsInstance);
7390  
7391    bool CheckARCMethodDecl(ObjCMethodDecl *method);
7392    bool inferObjCARCLifetime(ValueDecl *decl);
7393  
7394    ExprResult
7395    HandleExprPropertyRefExpr(const ObjCObjectPointerType *OPT,
7396                              Expr *BaseExpr,
7397                              SourceLocation OpLoc,
7398                              DeclarationName MemberName,
7399                              SourceLocation MemberLoc,
7400                              SourceLocation SuperLoc, QualType SuperType,
7401                              bool Super);
7402  
7403    ExprResult
7404    ActOnClassPropertyRefExpr(IdentifierInfo &receiverName,
7405                              IdentifierInfo &propertyName,
7406                              SourceLocation receiverNameLoc,
7407                              SourceLocation propertyNameLoc);
7408  
7409    ObjCMethodDecl *tryCaptureObjCSelf(SourceLocation Loc);
7410  
7411    /// \brief Describes the kind of message expression indicated by a message
7412    /// send that starts with an identifier.
7413    enum ObjCMessageKind {
7414      /// \brief The message is sent to 'super'.
7415      ObjCSuperMessage,
7416      /// \brief The message is an instance message.
7417      ObjCInstanceMessage,
7418      /// \brief The message is a class message, and the identifier is a type
7419      /// name.
7420      ObjCClassMessage
7421    };
7422  
7423    ObjCMessageKind getObjCMessageKind(Scope *S,
7424                                       IdentifierInfo *Name,
7425                                       SourceLocation NameLoc,
7426                                       bool IsSuper,
7427                                       bool HasTrailingDot,
7428                                       ParsedType &ReceiverType);
7429  
7430    ExprResult ActOnSuperMessage(Scope *S, SourceLocation SuperLoc,
7431                                 Selector Sel,
7432                                 SourceLocation LBracLoc,
7433                                 ArrayRef<SourceLocation> SelectorLocs,
7434                                 SourceLocation RBracLoc,
7435                                 MultiExprArg Args);
7436  
7437    ExprResult BuildClassMessage(TypeSourceInfo *ReceiverTypeInfo,
7438                                 QualType ReceiverType,
7439                                 SourceLocation SuperLoc,
7440                                 Selector Sel,
7441                                 ObjCMethodDecl *Method,
7442                                 SourceLocation LBracLoc,
7443                                 ArrayRef<SourceLocation> SelectorLocs,
7444                                 SourceLocation RBracLoc,
7445                                 MultiExprArg Args,
7446                                 bool isImplicit = false);
7447  
7448    ExprResult BuildClassMessageImplicit(QualType ReceiverType,
7449                                         bool isSuperReceiver,
7450                                         SourceLocation Loc,
7451                                         Selector Sel,
7452                                         ObjCMethodDecl *Method,
7453                                         MultiExprArg Args);
7454  
7455    ExprResult ActOnClassMessage(Scope *S,
7456                                 ParsedType Receiver,
7457                                 Selector Sel,
7458                                 SourceLocation LBracLoc,
7459                                 ArrayRef<SourceLocation> SelectorLocs,
7460                                 SourceLocation RBracLoc,
7461                                 MultiExprArg Args);
7462  
7463    ExprResult BuildInstanceMessage(Expr *Receiver,
7464                                    QualType ReceiverType,
7465                                    SourceLocation SuperLoc,
7466                                    Selector Sel,
7467                                    ObjCMethodDecl *Method,
7468                                    SourceLocation LBracLoc,
7469                                    ArrayRef<SourceLocation> SelectorLocs,
7470                                    SourceLocation RBracLoc,
7471                                    MultiExprArg Args,
7472                                    bool isImplicit = false);
7473  
7474    ExprResult BuildInstanceMessageImplicit(Expr *Receiver,
7475                                            QualType ReceiverType,
7476                                            SourceLocation Loc,
7477                                            Selector Sel,
7478                                            ObjCMethodDecl *Method,
7479                                            MultiExprArg Args);
7480  
7481    ExprResult ActOnInstanceMessage(Scope *S,
7482                                    Expr *Receiver,
7483                                    Selector Sel,
7484                                    SourceLocation LBracLoc,
7485                                    ArrayRef<SourceLocation> SelectorLocs,
7486                                    SourceLocation RBracLoc,
7487                                    MultiExprArg Args);
7488  
7489    ExprResult BuildObjCBridgedCast(SourceLocation LParenLoc,
7490                                    ObjCBridgeCastKind Kind,
7491                                    SourceLocation BridgeKeywordLoc,
7492                                    TypeSourceInfo *TSInfo,
7493                                    Expr *SubExpr);
7494  
7495    ExprResult ActOnObjCBridgedCast(Scope *S,
7496                                    SourceLocation LParenLoc,
7497                                    ObjCBridgeCastKind Kind,
7498                                    SourceLocation BridgeKeywordLoc,
7499                                    ParsedType Type,
7500                                    SourceLocation RParenLoc,
7501                                    Expr *SubExpr);
7502  
7503    void CheckTollFreeBridgeCast(QualType castType, Expr *castExpr);
7504  
7505    void CheckObjCBridgeRelatedCast(QualType castType, Expr *castExpr);
7506  
7507    bool CheckTollFreeBridgeStaticCast(QualType castType, Expr *castExpr,
7508                                       CastKind &Kind);
7509  
7510    bool checkObjCBridgeRelatedComponents(SourceLocation Loc,
7511                                          QualType DestType, QualType SrcType,
7512                                          ObjCInterfaceDecl *&RelatedClass,
7513                                          ObjCMethodDecl *&ClassMethod,
7514                                          ObjCMethodDecl *&InstanceMethod,
7515                                          TypedefNameDecl *&TDNDecl,
7516                                          bool CfToNs);
7517  
7518    bool CheckObjCBridgeRelatedConversions(SourceLocation Loc,
7519                                           QualType DestType, QualType SrcType,
7520                                           Expr *&SrcExpr);
7521  
7522    bool ConversionToObjCStringLiteralCheck(QualType DstType, Expr *&SrcExpr);
7523  
7524    bool checkInitMethod(ObjCMethodDecl *method, QualType receiverTypeIfCall);
7525  
7526    /// \brief Check whether the given new method is a valid override of the
7527    /// given overridden method, and set any properties that should be inherited.
7528    void CheckObjCMethodOverride(ObjCMethodDecl *NewMethod,
7529                                 const ObjCMethodDecl *Overridden);
7530  
7531    /// \brief Describes the compatibility of a result type with its method.
7532    enum ResultTypeCompatibilityKind {
7533      RTC_Compatible,
7534      RTC_Incompatible,
7535      RTC_Unknown
7536    };
7537  
7538    void CheckObjCMethodOverrides(ObjCMethodDecl *ObjCMethod,
7539                                  ObjCInterfaceDecl *CurrentClass,
7540                                  ResultTypeCompatibilityKind RTC);
7541  
7542    enum PragmaOptionsAlignKind {
7543      POAK_Native,  // #pragma options align=native
7544      POAK_Natural, // #pragma options align=natural
7545      POAK_Packed,  // #pragma options align=packed
7546      POAK_Power,   // #pragma options align=power
7547      POAK_Mac68k,  // #pragma options align=mac68k
7548      POAK_Reset    // #pragma options align=reset
7549    };
7550  
7551    /// ActOnPragmaOptionsAlign - Called on well formed \#pragma options align.
7552    void ActOnPragmaOptionsAlign(PragmaOptionsAlignKind Kind,
7553                                 SourceLocation PragmaLoc);
7554  
7555    enum PragmaPackKind {
7556      PPK_Default, // #pragma pack([n])
7557      PPK_Show,    // #pragma pack(show), only supported by MSVC.
7558      PPK_Push,    // #pragma pack(push, [identifier], [n])
7559      PPK_Pop      // #pragma pack(pop, [identifier], [n])
7560    };
7561  
7562    enum PragmaMSStructKind {
7563      PMSST_OFF,  // #pragms ms_struct off
7564      PMSST_ON    // #pragms ms_struct on
7565    };
7566  
7567    enum PragmaMSCommentKind {
7568      PCK_Unknown,
7569      PCK_Linker,   // #pragma comment(linker, ...)
7570      PCK_Lib,      // #pragma comment(lib, ...)
7571      PCK_Compiler, // #pragma comment(compiler, ...)
7572      PCK_ExeStr,   // #pragma comment(exestr, ...)
7573      PCK_User      // #pragma comment(user, ...)
7574    };
7575  
7576    /// ActOnPragmaPack - Called on well formed \#pragma pack(...).
7577    void ActOnPragmaPack(PragmaPackKind Kind,
7578                         IdentifierInfo *Name,
7579                         Expr *Alignment,
7580                         SourceLocation PragmaLoc,
7581                         SourceLocation LParenLoc,
7582                         SourceLocation RParenLoc);
7583  
7584    /// ActOnPragmaMSStruct - Called on well formed \#pragma ms_struct [on|off].
7585    void ActOnPragmaMSStruct(PragmaMSStructKind Kind);
7586  
7587    /// ActOnPragmaMSComment - Called on well formed
7588    /// \#pragma comment(kind, "arg").
7589    void ActOnPragmaMSComment(PragmaMSCommentKind Kind, StringRef Arg);
7590  
7591    /// ActOnPragmaMSPointersToMembers - called on well formed \#pragma
7592    /// pointers_to_members(representation method[, general purpose
7593    /// representation]).
7594    void ActOnPragmaMSPointersToMembers(
7595        LangOptions::PragmaMSPointersToMembersKind Kind,
7596        SourceLocation PragmaLoc);
7597  
7598    /// \brief Called on well formed \#pragma vtordisp().
7599    void ActOnPragmaMSVtorDisp(PragmaVtorDispKind Kind, SourceLocation PragmaLoc,
7600                               MSVtorDispAttr::Mode Value);
7601  
7602    enum PragmaSectionKind {
7603      PSK_DataSeg,
7604      PSK_BSSSeg,
7605      PSK_ConstSeg,
7606      PSK_CodeSeg,
7607    };
7608  
7609    bool UnifySection(StringRef SectionName,
7610                      int SectionFlags,
7611                      DeclaratorDecl *TheDecl);
7612    bool UnifySection(StringRef SectionName,
7613                      int SectionFlags,
7614                      SourceLocation PragmaSectionLocation);
7615  
7616    /// \brief Called on well formed \#pragma bss_seg/data_seg/const_seg/code_seg.
7617    void ActOnPragmaMSSeg(SourceLocation PragmaLocation,
7618                          PragmaMsStackAction Action,
7619                          llvm::StringRef StackSlotLabel,
7620                          StringLiteral *SegmentName,
7621                          llvm::StringRef PragmaName);
7622  
7623    /// \brief Called on well formed \#pragma section().
7624    void ActOnPragmaMSSection(SourceLocation PragmaLocation,
7625                              int SectionFlags, StringLiteral *SegmentName);
7626  
7627    /// \brief Called on well-formed \#pragma init_seg().
7628    void ActOnPragmaMSInitSeg(SourceLocation PragmaLocation,
7629                              StringLiteral *SegmentName);
7630  
7631    /// ActOnPragmaDetectMismatch - Call on well-formed \#pragma detect_mismatch
7632    void ActOnPragmaDetectMismatch(StringRef Name, StringRef Value);
7633  
7634    /// ActOnPragmaUnused - Called on well-formed '\#pragma unused'.
7635    void ActOnPragmaUnused(const Token &Identifier,
7636                           Scope *curScope,
7637                           SourceLocation PragmaLoc);
7638  
7639    /// ActOnPragmaVisibility - Called on well formed \#pragma GCC visibility... .
7640    void ActOnPragmaVisibility(const IdentifierInfo* VisType,
7641                               SourceLocation PragmaLoc);
7642  
7643    NamedDecl *DeclClonePragmaWeak(NamedDecl *ND, IdentifierInfo *II,
7644                                   SourceLocation Loc);
7645    void DeclApplyPragmaWeak(Scope *S, NamedDecl *ND, WeakInfo &W);
7646  
7647    /// ActOnPragmaWeakID - Called on well formed \#pragma weak ident.
7648    void ActOnPragmaWeakID(IdentifierInfo* WeakName,
7649                           SourceLocation PragmaLoc,
7650                           SourceLocation WeakNameLoc);
7651  
7652    /// ActOnPragmaRedefineExtname - Called on well formed
7653    /// \#pragma redefine_extname oldname newname.
7654    void ActOnPragmaRedefineExtname(IdentifierInfo* WeakName,
7655                                    IdentifierInfo* AliasName,
7656                                    SourceLocation PragmaLoc,
7657                                    SourceLocation WeakNameLoc,
7658                                    SourceLocation AliasNameLoc);
7659  
7660    /// ActOnPragmaWeakAlias - Called on well formed \#pragma weak ident = ident.
7661    void ActOnPragmaWeakAlias(IdentifierInfo* WeakName,
7662                              IdentifierInfo* AliasName,
7663                              SourceLocation PragmaLoc,
7664                              SourceLocation WeakNameLoc,
7665                              SourceLocation AliasNameLoc);
7666  
7667    /// ActOnPragmaFPContract - Called on well formed
7668    /// \#pragma {STDC,OPENCL} FP_CONTRACT
7669    void ActOnPragmaFPContract(tok::OnOffSwitch OOS);
7670  
7671    /// AddAlignmentAttributesForRecord - Adds any needed alignment attributes to
7672    /// a the record decl, to handle '\#pragma pack' and '\#pragma options align'.
7673    void AddAlignmentAttributesForRecord(RecordDecl *RD);
7674  
7675    /// AddMsStructLayoutForRecord - Adds ms_struct layout attribute to record.
7676    void AddMsStructLayoutForRecord(RecordDecl *RD);
7677  
7678    /// FreePackedContext - Deallocate and null out PackContext.
7679    void FreePackedContext();
7680  
7681    /// PushNamespaceVisibilityAttr - Note that we've entered a
7682    /// namespace with a visibility attribute.
7683    void PushNamespaceVisibilityAttr(const VisibilityAttr *Attr,
7684                                     SourceLocation Loc);
7685  
7686    /// AddPushedVisibilityAttribute - If '\#pragma GCC visibility' was used,
7687    /// add an appropriate visibility attribute.
7688    void AddPushedVisibilityAttribute(Decl *RD);
7689  
7690    /// PopPragmaVisibility - Pop the top element of the visibility stack; used
7691    /// for '\#pragma GCC visibility' and visibility attributes on namespaces.
7692    void PopPragmaVisibility(bool IsNamespaceEnd, SourceLocation EndLoc);
7693  
7694    /// FreeVisContext - Deallocate and null out VisContext.
7695    void FreeVisContext();
7696  
7697    /// AddCFAuditedAttribute - Check whether we're currently within
7698    /// '\#pragma clang arc_cf_code_audited' and, if so, consider adding
7699    /// the appropriate attribute.
7700    void AddCFAuditedAttribute(Decl *D);
7701  
7702    /// \brief Called on well formed \#pragma clang optimize.
7703    void ActOnPragmaOptimize(bool On, SourceLocation PragmaLoc);
7704  
7705    /// \brief Get the location for the currently active "\#pragma clang optimize
7706    /// off". If this location is invalid, then the state of the pragma is "on".
getOptimizeOffPragmaLocation()7707    SourceLocation getOptimizeOffPragmaLocation() const {
7708      return OptimizeOffPragmaLocation;
7709    }
7710  
7711    /// \brief Only called on function definitions; if there is a pragma in scope
7712    /// with the effect of a range-based optnone, consider marking the function
7713    /// with attribute optnone.
7714    void AddRangeBasedOptnone(FunctionDecl *FD);
7715  
7716    /// \brief Adds the 'optnone' attribute to the function declaration if there
7717    /// are no conflicts; Loc represents the location causing the 'optnone'
7718    /// attribute to be added (usually because of a pragma).
7719    void AddOptnoneAttributeIfNoConflicts(FunctionDecl *FD, SourceLocation Loc);
7720  
7721    /// AddAlignedAttr - Adds an aligned attribute to a particular declaration.
7722    void AddAlignedAttr(SourceRange AttrRange, Decl *D, Expr *E,
7723                        unsigned SpellingListIndex, bool IsPackExpansion);
7724    void AddAlignedAttr(SourceRange AttrRange, Decl *D, TypeSourceInfo *T,
7725                        unsigned SpellingListIndex, bool IsPackExpansion);
7726  
7727    /// AddAssumeAlignedAttr - Adds an assume_aligned attribute to a particular
7728    /// declaration.
7729    void AddAssumeAlignedAttr(SourceRange AttrRange, Decl *D, Expr *E, Expr *OE,
7730                              unsigned SpellingListIndex);
7731  
7732    /// AddAlignValueAttr - Adds an align_value attribute to a particular
7733    /// declaration.
7734    void AddAlignValueAttr(SourceRange AttrRange, Decl *D, Expr *E,
7735                           unsigned SpellingListIndex);
7736  
7737    /// AddLaunchBoundsAttr - Adds a launch_bounds attribute to a particular
7738    /// declaration.
7739    void AddLaunchBoundsAttr(SourceRange AttrRange, Decl *D, Expr *MaxThreads,
7740                             Expr *MinBlocks, unsigned SpellingListIndex);
7741  
7742    //===--------------------------------------------------------------------===//
7743    // C++ Coroutines TS
7744    //
7745    ExprResult ActOnCoawaitExpr(Scope *S, SourceLocation KwLoc, Expr *E);
7746    ExprResult ActOnCoyieldExpr(Scope *S, SourceLocation KwLoc, Expr *E);
7747    StmtResult ActOnCoreturnStmt(SourceLocation KwLoc, Expr *E);
7748  
7749    ExprResult BuildCoawaitExpr(SourceLocation KwLoc, Expr *E);
7750    ExprResult BuildCoyieldExpr(SourceLocation KwLoc, Expr *E);
7751    StmtResult BuildCoreturnStmt(SourceLocation KwLoc, Expr *E);
7752  
7753    void CheckCompletedCoroutineBody(FunctionDecl *FD, Stmt *&Body);
7754  
7755    //===--------------------------------------------------------------------===//
7756    // OpenMP directives and clauses.
7757    //
7758  private:
7759    void *VarDataSharingAttributesStack;
7760    /// \brief Initialization of data-sharing attributes stack.
7761    void InitDataSharingAttributesStack();
7762    void DestroyDataSharingAttributesStack();
7763    ExprResult VerifyPositiveIntegerConstantInClause(Expr *Op,
7764                                                     OpenMPClauseKind CKind);
7765  public:
7766    /// \brief Return true if the provided declaration \a VD should be captured by
7767    /// reference in the provided scope \a RSI. This will take into account the
7768    /// semantics of the directive and associated clauses.
7769    bool IsOpenMPCapturedByRef(VarDecl *VD,
7770                               const sema::CapturedRegionScopeInfo *RSI);
7771  
7772    /// \brief Check if the specified variable is used in one of the private
7773    /// clauses (private, firstprivate, lastprivate, reduction etc.) in OpenMP
7774    /// constructs.
7775    bool IsOpenMPCapturedVar(VarDecl *VD);
7776  
7777    /// \brief Check if the specified variable is used in 'private' clause.
7778    /// \param Level Relative level of nested OpenMP construct for that the check
7779    /// is performed.
7780    bool isOpenMPPrivateVar(VarDecl *VD, unsigned Level);
7781  
7782    /// \brief Check if the specified variable is captured  by 'target' directive.
7783    /// \param Level Relative level of nested OpenMP construct for that the check
7784    /// is performed.
7785    bool isOpenMPTargetCapturedVar(VarDecl *VD, unsigned Level);
7786  
7787    ExprResult PerformOpenMPImplicitIntegerConversion(SourceLocation OpLoc,
7788                                                      Expr *Op);
7789    /// \brief Called on start of new data sharing attribute block.
7790    void StartOpenMPDSABlock(OpenMPDirectiveKind K,
7791                             const DeclarationNameInfo &DirName, Scope *CurScope,
7792                             SourceLocation Loc);
7793    /// \brief Start analysis of clauses.
7794    void StartOpenMPClause(OpenMPClauseKind K);
7795    /// \brief End analysis of clauses.
7796    void EndOpenMPClause();
7797    /// \brief Called on end of data sharing attribute block.
7798    void EndOpenMPDSABlock(Stmt *CurDirective);
7799  
7800    /// \brief Check if the current region is an OpenMP loop region and if it is,
7801    /// mark loop control variable, used in \p Init for loop initialization, as
7802    /// private by default.
7803    /// \param Init First part of the for loop.
7804    void ActOnOpenMPLoopInitialization(SourceLocation ForLoc, Stmt *Init);
7805  
7806    // OpenMP directives and clauses.
7807    /// \brief Called on correct id-expression from the '#pragma omp
7808    /// threadprivate'.
7809    ExprResult ActOnOpenMPIdExpression(Scope *CurScope,
7810                                       CXXScopeSpec &ScopeSpec,
7811                                       const DeclarationNameInfo &Id);
7812    /// \brief Called on well-formed '#pragma omp threadprivate'.
7813    DeclGroupPtrTy ActOnOpenMPThreadprivateDirective(
7814                                       SourceLocation Loc,
7815                                       ArrayRef<Expr *> VarList);
7816    /// \brief Builds a new OpenMPThreadPrivateDecl and checks its correctness.
7817    OMPThreadPrivateDecl *CheckOMPThreadPrivateDecl(
7818                                       SourceLocation Loc,
7819                                       ArrayRef<Expr *> VarList);
7820  
7821    /// \brief Initialization of captured region for OpenMP region.
7822    void ActOnOpenMPRegionStart(OpenMPDirectiveKind DKind, Scope *CurScope);
7823    /// \brief End of OpenMP region.
7824    ///
7825    /// \param S Statement associated with the current OpenMP region.
7826    /// \param Clauses List of clauses for the current OpenMP region.
7827    ///
7828    /// \returns Statement for finished OpenMP region.
7829    StmtResult ActOnOpenMPRegionEnd(StmtResult S, ArrayRef<OMPClause *> Clauses);
7830    StmtResult ActOnOpenMPExecutableDirective(
7831        OpenMPDirectiveKind Kind, const DeclarationNameInfo &DirName,
7832        OpenMPDirectiveKind CancelRegion, ArrayRef<OMPClause *> Clauses,
7833        Stmt *AStmt, SourceLocation StartLoc, SourceLocation EndLoc);
7834    /// \brief Called on well-formed '\#pragma omp parallel' after parsing
7835    /// of the  associated statement.
7836    StmtResult ActOnOpenMPParallelDirective(ArrayRef<OMPClause *> Clauses,
7837                                            Stmt *AStmt,
7838                                            SourceLocation StartLoc,
7839                                            SourceLocation EndLoc);
7840    /// \brief Called on well-formed '\#pragma omp simd' after parsing
7841    /// of the associated statement.
7842    StmtResult ActOnOpenMPSimdDirective(
7843        ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
7844        SourceLocation EndLoc,
7845        llvm::DenseMap<VarDecl *, Expr *> &VarsWithImplicitDSA);
7846    /// \brief Called on well-formed '\#pragma omp for' after parsing
7847    /// of the associated statement.
7848    StmtResult ActOnOpenMPForDirective(
7849        ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
7850        SourceLocation EndLoc,
7851        llvm::DenseMap<VarDecl *, Expr *> &VarsWithImplicitDSA);
7852    /// \brief Called on well-formed '\#pragma omp for simd' after parsing
7853    /// of the associated statement.
7854    StmtResult ActOnOpenMPForSimdDirective(
7855        ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
7856        SourceLocation EndLoc,
7857        llvm::DenseMap<VarDecl *, Expr *> &VarsWithImplicitDSA);
7858    /// \brief Called on well-formed '\#pragma omp sections' after parsing
7859    /// of the associated statement.
7860    StmtResult ActOnOpenMPSectionsDirective(ArrayRef<OMPClause *> Clauses,
7861                                            Stmt *AStmt, SourceLocation StartLoc,
7862                                            SourceLocation EndLoc);
7863    /// \brief Called on well-formed '\#pragma omp section' after parsing of the
7864    /// associated statement.
7865    StmtResult ActOnOpenMPSectionDirective(Stmt *AStmt, SourceLocation StartLoc,
7866                                           SourceLocation EndLoc);
7867    /// \brief Called on well-formed '\#pragma omp single' after parsing of the
7868    /// associated statement.
7869    StmtResult ActOnOpenMPSingleDirective(ArrayRef<OMPClause *> Clauses,
7870                                          Stmt *AStmt, SourceLocation StartLoc,
7871                                          SourceLocation EndLoc);
7872    /// \brief Called on well-formed '\#pragma omp master' after parsing of the
7873    /// associated statement.
7874    StmtResult ActOnOpenMPMasterDirective(Stmt *AStmt, SourceLocation StartLoc,
7875                                          SourceLocation EndLoc);
7876    /// \brief Called on well-formed '\#pragma omp critical' after parsing of the
7877    /// associated statement.
7878    StmtResult ActOnOpenMPCriticalDirective(const DeclarationNameInfo &DirName,
7879                                            ArrayRef<OMPClause *> Clauses,
7880                                            Stmt *AStmt, SourceLocation StartLoc,
7881                                            SourceLocation EndLoc);
7882    /// \brief Called on well-formed '\#pragma omp parallel for' after parsing
7883    /// of the  associated statement.
7884    StmtResult ActOnOpenMPParallelForDirective(
7885        ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
7886        SourceLocation EndLoc,
7887        llvm::DenseMap<VarDecl *, Expr *> &VarsWithImplicitDSA);
7888    /// \brief Called on well-formed '\#pragma omp parallel for simd' after
7889    /// parsing of the  associated statement.
7890    StmtResult ActOnOpenMPParallelForSimdDirective(
7891        ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
7892        SourceLocation EndLoc,
7893        llvm::DenseMap<VarDecl *, Expr *> &VarsWithImplicitDSA);
7894    /// \brief Called on well-formed '\#pragma omp parallel sections' after
7895    /// parsing of the  associated statement.
7896    StmtResult ActOnOpenMPParallelSectionsDirective(ArrayRef<OMPClause *> Clauses,
7897                                                    Stmt *AStmt,
7898                                                    SourceLocation StartLoc,
7899                                                    SourceLocation EndLoc);
7900    /// \brief Called on well-formed '\#pragma omp task' after parsing of the
7901    /// associated statement.
7902    StmtResult ActOnOpenMPTaskDirective(ArrayRef<OMPClause *> Clauses,
7903                                        Stmt *AStmt, SourceLocation StartLoc,
7904                                        SourceLocation EndLoc);
7905    /// \brief Called on well-formed '\#pragma omp taskyield'.
7906    StmtResult ActOnOpenMPTaskyieldDirective(SourceLocation StartLoc,
7907                                             SourceLocation EndLoc);
7908    /// \brief Called on well-formed '\#pragma omp barrier'.
7909    StmtResult ActOnOpenMPBarrierDirective(SourceLocation StartLoc,
7910                                           SourceLocation EndLoc);
7911    /// \brief Called on well-formed '\#pragma omp taskwait'.
7912    StmtResult ActOnOpenMPTaskwaitDirective(SourceLocation StartLoc,
7913                                            SourceLocation EndLoc);
7914    /// \brief Called on well-formed '\#pragma omp taskgroup'.
7915    StmtResult ActOnOpenMPTaskgroupDirective(Stmt *AStmt, SourceLocation StartLoc,
7916                                             SourceLocation EndLoc);
7917    /// \brief Called on well-formed '\#pragma omp flush'.
7918    StmtResult ActOnOpenMPFlushDirective(ArrayRef<OMPClause *> Clauses,
7919                                         SourceLocation StartLoc,
7920                                         SourceLocation EndLoc);
7921    /// \brief Called on well-formed '\#pragma omp ordered' after parsing of the
7922    /// associated statement.
7923    StmtResult ActOnOpenMPOrderedDirective(ArrayRef<OMPClause *> Clauses,
7924                                           Stmt *AStmt, SourceLocation StartLoc,
7925                                           SourceLocation EndLoc);
7926    /// \brief Called on well-formed '\#pragma omp atomic' after parsing of the
7927    /// associated statement.
7928    StmtResult ActOnOpenMPAtomicDirective(ArrayRef<OMPClause *> Clauses,
7929                                          Stmt *AStmt, SourceLocation StartLoc,
7930                                          SourceLocation EndLoc);
7931    /// \brief Called on well-formed '\#pragma omp target' after parsing of the
7932    /// associated statement.
7933    StmtResult ActOnOpenMPTargetDirective(ArrayRef<OMPClause *> Clauses,
7934                                          Stmt *AStmt, SourceLocation StartLoc,
7935                                          SourceLocation EndLoc);
7936    /// \brief Called on well-formed '\#pragma omp target data' after parsing of
7937    /// the associated statement.
7938    StmtResult ActOnOpenMPTargetDataDirective(ArrayRef<OMPClause *> Clauses,
7939                                              Stmt *AStmt, SourceLocation StartLoc,
7940                                              SourceLocation EndLoc);
7941    /// \brief Called on well-formed '\#pragma omp teams' after parsing of the
7942    /// associated statement.
7943    StmtResult ActOnOpenMPTeamsDirective(ArrayRef<OMPClause *> Clauses,
7944                                         Stmt *AStmt, SourceLocation StartLoc,
7945                                         SourceLocation EndLoc);
7946    /// \brief Called on well-formed '\#pragma omp cancellation point'.
7947    StmtResult
7948    ActOnOpenMPCancellationPointDirective(SourceLocation StartLoc,
7949                                          SourceLocation EndLoc,
7950                                          OpenMPDirectiveKind CancelRegion);
7951    /// \brief Called on well-formed '\#pragma omp cancel'.
7952    StmtResult ActOnOpenMPCancelDirective(ArrayRef<OMPClause *> Clauses,
7953                                          SourceLocation StartLoc,
7954                                          SourceLocation EndLoc,
7955                                          OpenMPDirectiveKind CancelRegion);
7956    /// \brief Called on well-formed '\#pragma omp taskloop' after parsing of the
7957    /// associated statement.
7958    StmtResult ActOnOpenMPTaskLoopDirective(
7959        ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
7960        SourceLocation EndLoc,
7961        llvm::DenseMap<VarDecl *, Expr *> &VarsWithImplicitDSA);
7962    /// \brief Called on well-formed '\#pragma omp taskloop simd' after parsing of
7963    /// the associated statement.
7964    StmtResult ActOnOpenMPTaskLoopSimdDirective(
7965        ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
7966        SourceLocation EndLoc,
7967        llvm::DenseMap<VarDecl *, Expr *> &VarsWithImplicitDSA);
7968    /// \brief Called on well-formed '\#pragma omp distribute' after parsing
7969    /// of the associated statement.
7970    StmtResult ActOnOpenMPDistributeDirective(
7971        ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
7972        SourceLocation EndLoc,
7973        llvm::DenseMap<VarDecl *, Expr *> &VarsWithImplicitDSA);
7974  
7975    OMPClause *ActOnOpenMPSingleExprClause(OpenMPClauseKind Kind,
7976                                           Expr *Expr,
7977                                           SourceLocation StartLoc,
7978                                           SourceLocation LParenLoc,
7979                                           SourceLocation EndLoc);
7980    /// \brief Called on well-formed 'if' clause.
7981    OMPClause *ActOnOpenMPIfClause(OpenMPDirectiveKind NameModifier,
7982                                   Expr *Condition, SourceLocation StartLoc,
7983                                   SourceLocation LParenLoc,
7984                                   SourceLocation NameModifierLoc,
7985                                   SourceLocation ColonLoc,
7986                                   SourceLocation EndLoc);
7987    /// \brief Called on well-formed 'final' clause.
7988    OMPClause *ActOnOpenMPFinalClause(Expr *Condition, SourceLocation StartLoc,
7989                                      SourceLocation LParenLoc,
7990                                      SourceLocation EndLoc);
7991    /// \brief Called on well-formed 'num_threads' clause.
7992    OMPClause *ActOnOpenMPNumThreadsClause(Expr *NumThreads,
7993                                           SourceLocation StartLoc,
7994                                           SourceLocation LParenLoc,
7995                                           SourceLocation EndLoc);
7996    /// \brief Called on well-formed 'safelen' clause.
7997    OMPClause *ActOnOpenMPSafelenClause(Expr *Length,
7998                                        SourceLocation StartLoc,
7999                                        SourceLocation LParenLoc,
8000                                        SourceLocation EndLoc);
8001    /// \brief Called on well-formed 'simdlen' clause.
8002    OMPClause *ActOnOpenMPSimdlenClause(Expr *Length, SourceLocation StartLoc,
8003                                        SourceLocation LParenLoc,
8004                                        SourceLocation EndLoc);
8005    /// \brief Called on well-formed 'collapse' clause.
8006    OMPClause *ActOnOpenMPCollapseClause(Expr *NumForLoops,
8007                                         SourceLocation StartLoc,
8008                                         SourceLocation LParenLoc,
8009                                         SourceLocation EndLoc);
8010    /// \brief Called on well-formed 'ordered' clause.
8011    OMPClause *
8012    ActOnOpenMPOrderedClause(SourceLocation StartLoc, SourceLocation EndLoc,
8013                             SourceLocation LParenLoc = SourceLocation(),
8014                             Expr *NumForLoops = nullptr);
8015    /// \brief Called on well-formed 'grainsize' clause.
8016    OMPClause *ActOnOpenMPGrainsizeClause(Expr *Size, SourceLocation StartLoc,
8017                                          SourceLocation LParenLoc,
8018                                          SourceLocation EndLoc);
8019    /// \brief Called on well-formed 'num_tasks' clause.
8020    OMPClause *ActOnOpenMPNumTasksClause(Expr *NumTasks, SourceLocation StartLoc,
8021                                         SourceLocation LParenLoc,
8022                                         SourceLocation EndLoc);
8023    /// \brief Called on well-formed 'hint' clause.
8024    OMPClause *ActOnOpenMPHintClause(Expr *Hint, SourceLocation StartLoc,
8025                                     SourceLocation LParenLoc,
8026                                     SourceLocation EndLoc);
8027  
8028    OMPClause *ActOnOpenMPSimpleClause(OpenMPClauseKind Kind,
8029                                       unsigned Argument,
8030                                       SourceLocation ArgumentLoc,
8031                                       SourceLocation StartLoc,
8032                                       SourceLocation LParenLoc,
8033                                       SourceLocation EndLoc);
8034    /// \brief Called on well-formed 'default' clause.
8035    OMPClause *ActOnOpenMPDefaultClause(OpenMPDefaultClauseKind Kind,
8036                                        SourceLocation KindLoc,
8037                                        SourceLocation StartLoc,
8038                                        SourceLocation LParenLoc,
8039                                        SourceLocation EndLoc);
8040    /// \brief Called on well-formed 'proc_bind' clause.
8041    OMPClause *ActOnOpenMPProcBindClause(OpenMPProcBindClauseKind Kind,
8042                                         SourceLocation KindLoc,
8043                                         SourceLocation StartLoc,
8044                                         SourceLocation LParenLoc,
8045                                         SourceLocation EndLoc);
8046  
8047    OMPClause *ActOnOpenMPSingleExprWithArgClause(OpenMPClauseKind Kind,
8048                                                  unsigned Argument, Expr *Expr,
8049                                                  SourceLocation StartLoc,
8050                                                  SourceLocation LParenLoc,
8051                                                  SourceLocation ArgumentLoc,
8052                                                  SourceLocation DelimLoc,
8053                                                  SourceLocation EndLoc);
8054    /// \brief Called on well-formed 'schedule' clause.
8055    OMPClause *ActOnOpenMPScheduleClause(OpenMPScheduleClauseKind Kind,
8056                                         Expr *ChunkSize, SourceLocation StartLoc,
8057                                         SourceLocation LParenLoc,
8058                                         SourceLocation KindLoc,
8059                                         SourceLocation CommaLoc,
8060                                         SourceLocation EndLoc);
8061  
8062    OMPClause *ActOnOpenMPClause(OpenMPClauseKind Kind, SourceLocation StartLoc,
8063                                 SourceLocation EndLoc);
8064    /// \brief Called on well-formed 'nowait' clause.
8065    OMPClause *ActOnOpenMPNowaitClause(SourceLocation StartLoc,
8066                                       SourceLocation EndLoc);
8067    /// \brief Called on well-formed 'untied' clause.
8068    OMPClause *ActOnOpenMPUntiedClause(SourceLocation StartLoc,
8069                                       SourceLocation EndLoc);
8070    /// \brief Called on well-formed 'mergeable' clause.
8071    OMPClause *ActOnOpenMPMergeableClause(SourceLocation StartLoc,
8072                                          SourceLocation EndLoc);
8073    /// \brief Called on well-formed 'read' clause.
8074    OMPClause *ActOnOpenMPReadClause(SourceLocation StartLoc,
8075                                     SourceLocation EndLoc);
8076    /// \brief Called on well-formed 'write' clause.
8077    OMPClause *ActOnOpenMPWriteClause(SourceLocation StartLoc,
8078                                      SourceLocation EndLoc);
8079    /// \brief Called on well-formed 'update' clause.
8080    OMPClause *ActOnOpenMPUpdateClause(SourceLocation StartLoc,
8081                                       SourceLocation EndLoc);
8082    /// \brief Called on well-formed 'capture' clause.
8083    OMPClause *ActOnOpenMPCaptureClause(SourceLocation StartLoc,
8084                                        SourceLocation EndLoc);
8085    /// \brief Called on well-formed 'seq_cst' clause.
8086    OMPClause *ActOnOpenMPSeqCstClause(SourceLocation StartLoc,
8087                                       SourceLocation EndLoc);
8088    /// \brief Called on well-formed 'threads' clause.
8089    OMPClause *ActOnOpenMPThreadsClause(SourceLocation StartLoc,
8090                                        SourceLocation EndLoc);
8091    /// \brief Called on well-formed 'simd' clause.
8092    OMPClause *ActOnOpenMPSIMDClause(SourceLocation StartLoc,
8093                                     SourceLocation EndLoc);
8094    /// \brief Called on well-formed 'nogroup' clause.
8095    OMPClause *ActOnOpenMPNogroupClause(SourceLocation StartLoc,
8096                                        SourceLocation EndLoc);
8097  
8098    OMPClause *ActOnOpenMPVarListClause(
8099        OpenMPClauseKind Kind, ArrayRef<Expr *> Vars, Expr *TailExpr,
8100        SourceLocation StartLoc, SourceLocation LParenLoc,
8101        SourceLocation ColonLoc, SourceLocation EndLoc,
8102        CXXScopeSpec &ReductionIdScopeSpec,
8103        const DeclarationNameInfo &ReductionId, OpenMPDependClauseKind DepKind,
8104        OpenMPLinearClauseKind LinKind, OpenMPMapClauseKind MapTypeModifier,
8105        OpenMPMapClauseKind MapType, SourceLocation DepLinMapLoc);
8106    /// \brief Called on well-formed 'private' clause.
8107    OMPClause *ActOnOpenMPPrivateClause(ArrayRef<Expr *> VarList,
8108                                        SourceLocation StartLoc,
8109                                        SourceLocation LParenLoc,
8110                                        SourceLocation EndLoc);
8111    /// \brief Called on well-formed 'firstprivate' clause.
8112    OMPClause *ActOnOpenMPFirstprivateClause(ArrayRef<Expr *> VarList,
8113                                             SourceLocation StartLoc,
8114                                             SourceLocation LParenLoc,
8115                                             SourceLocation EndLoc);
8116    /// \brief Called on well-formed 'lastprivate' clause.
8117    OMPClause *ActOnOpenMPLastprivateClause(ArrayRef<Expr *> VarList,
8118                                            SourceLocation StartLoc,
8119                                            SourceLocation LParenLoc,
8120                                            SourceLocation EndLoc);
8121    /// \brief Called on well-formed 'shared' clause.
8122    OMPClause *ActOnOpenMPSharedClause(ArrayRef<Expr *> VarList,
8123                                       SourceLocation StartLoc,
8124                                       SourceLocation LParenLoc,
8125                                       SourceLocation EndLoc);
8126    /// \brief Called on well-formed 'reduction' clause.
8127    OMPClause *
8128    ActOnOpenMPReductionClause(ArrayRef<Expr *> VarList, SourceLocation StartLoc,
8129                               SourceLocation LParenLoc, SourceLocation ColonLoc,
8130                               SourceLocation EndLoc,
8131                               CXXScopeSpec &ReductionIdScopeSpec,
8132                               const DeclarationNameInfo &ReductionId);
8133    /// \brief Called on well-formed 'linear' clause.
8134    OMPClause *
8135    ActOnOpenMPLinearClause(ArrayRef<Expr *> VarList, Expr *Step,
8136                            SourceLocation StartLoc, SourceLocation LParenLoc,
8137                            OpenMPLinearClauseKind LinKind, SourceLocation LinLoc,
8138                            SourceLocation ColonLoc, SourceLocation EndLoc);
8139    /// \brief Called on well-formed 'aligned' clause.
8140    OMPClause *ActOnOpenMPAlignedClause(ArrayRef<Expr *> VarList,
8141                                        Expr *Alignment,
8142                                        SourceLocation StartLoc,
8143                                        SourceLocation LParenLoc,
8144                                        SourceLocation ColonLoc,
8145                                        SourceLocation EndLoc);
8146    /// \brief Called on well-formed 'copyin' clause.
8147    OMPClause *ActOnOpenMPCopyinClause(ArrayRef<Expr *> VarList,
8148                                       SourceLocation StartLoc,
8149                                       SourceLocation LParenLoc,
8150                                       SourceLocation EndLoc);
8151    /// \brief Called on well-formed 'copyprivate' clause.
8152    OMPClause *ActOnOpenMPCopyprivateClause(ArrayRef<Expr *> VarList,
8153                                            SourceLocation StartLoc,
8154                                            SourceLocation LParenLoc,
8155                                            SourceLocation EndLoc);
8156    /// \brief Called on well-formed 'flush' pseudo clause.
8157    OMPClause *ActOnOpenMPFlushClause(ArrayRef<Expr *> VarList,
8158                                      SourceLocation StartLoc,
8159                                      SourceLocation LParenLoc,
8160                                      SourceLocation EndLoc);
8161    /// \brief Called on well-formed 'depend' clause.
8162    OMPClause *
8163    ActOnOpenMPDependClause(OpenMPDependClauseKind DepKind, SourceLocation DepLoc,
8164                            SourceLocation ColonLoc, ArrayRef<Expr *> VarList,
8165                            SourceLocation StartLoc, SourceLocation LParenLoc,
8166                            SourceLocation EndLoc);
8167    /// \brief Called on well-formed 'device' clause.
8168    OMPClause *ActOnOpenMPDeviceClause(Expr *Device, SourceLocation StartLoc,
8169                                       SourceLocation LParenLoc,
8170                                       SourceLocation EndLoc);
8171    /// \brief Called on well-formed 'map' clause.
8172    OMPClause *ActOnOpenMPMapClause(
8173        OpenMPMapClauseKind MapTypeModifier, OpenMPMapClauseKind MapType,
8174        SourceLocation MapLoc, SourceLocation ColonLoc, ArrayRef<Expr *> VarList,
8175        SourceLocation StartLoc, SourceLocation LParenLoc, SourceLocation EndLoc);
8176    /// \brief Called on well-formed 'num_teams' clause.
8177    OMPClause *ActOnOpenMPNumTeamsClause(Expr *NumTeams, SourceLocation StartLoc,
8178                                         SourceLocation LParenLoc,
8179                                         SourceLocation EndLoc);
8180    /// \brief Called on well-formed 'thread_limit' clause.
8181    OMPClause *ActOnOpenMPThreadLimitClause(Expr *ThreadLimit,
8182                                            SourceLocation StartLoc,
8183                                            SourceLocation LParenLoc,
8184                                            SourceLocation EndLoc);
8185    /// \brief Called on well-formed 'priority' clause.
8186    OMPClause *ActOnOpenMPPriorityClause(Expr *Priority, SourceLocation StartLoc,
8187                                         SourceLocation LParenLoc,
8188                                         SourceLocation EndLoc);
8189  
8190    /// \brief The kind of conversion being performed.
8191    enum CheckedConversionKind {
8192      /// \brief An implicit conversion.
8193      CCK_ImplicitConversion,
8194      /// \brief A C-style cast.
8195      CCK_CStyleCast,
8196      /// \brief A functional-style cast.
8197      CCK_FunctionalCast,
8198      /// \brief A cast other than a C-style cast.
8199      CCK_OtherCast
8200    };
8201  
8202    /// ImpCastExprToType - If Expr is not of type 'Type', insert an implicit
8203    /// cast.  If there is already an implicit cast, merge into the existing one.
8204    /// If isLvalue, the result of the cast is an lvalue.
8205    ExprResult ImpCastExprToType(Expr *E, QualType Type, CastKind CK,
8206                                 ExprValueKind VK = VK_RValue,
8207                                 const CXXCastPath *BasePath = nullptr,
8208                                 CheckedConversionKind CCK
8209                                    = CCK_ImplicitConversion);
8210  
8211    /// ScalarTypeToBooleanCastKind - Returns the cast kind corresponding
8212    /// to the conversion from scalar type ScalarTy to the Boolean type.
8213    static CastKind ScalarTypeToBooleanCastKind(QualType ScalarTy);
8214  
8215    /// IgnoredValueConversions - Given that an expression's result is
8216    /// syntactically ignored, perform any conversions that are
8217    /// required.
8218    ExprResult IgnoredValueConversions(Expr *E);
8219  
8220    // UsualUnaryConversions - promotes integers (C99 6.3.1.1p2) and converts
8221    // functions and arrays to their respective pointers (C99 6.3.2.1).
8222    ExprResult UsualUnaryConversions(Expr *E);
8223  
8224    /// CallExprUnaryConversions - a special case of an unary conversion
8225    /// performed on a function designator of a call expression.
8226    ExprResult CallExprUnaryConversions(Expr *E);
8227  
8228    // DefaultFunctionArrayConversion - converts functions and arrays
8229    // to their respective pointers (C99 6.3.2.1).
8230    ExprResult DefaultFunctionArrayConversion(Expr *E, bool Diagnose = true);
8231  
8232    // DefaultFunctionArrayLvalueConversion - converts functions and
8233    // arrays to their respective pointers and performs the
8234    // lvalue-to-rvalue conversion.
8235    ExprResult DefaultFunctionArrayLvalueConversion(Expr *E,
8236                                                    bool Diagnose = true);
8237  
8238    // DefaultLvalueConversion - performs lvalue-to-rvalue conversion on
8239    // the operand.  This is DefaultFunctionArrayLvalueConversion,
8240    // except that it assumes the operand isn't of function or array
8241    // type.
8242    ExprResult DefaultLvalueConversion(Expr *E);
8243  
8244    // DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that
8245    // do not have a prototype. Integer promotions are performed on each
8246    // argument, and arguments that have type float are promoted to double.
8247    ExprResult DefaultArgumentPromotion(Expr *E);
8248  
8249    // Used for emitting the right warning by DefaultVariadicArgumentPromotion
8250    enum VariadicCallType {
8251      VariadicFunction,
8252      VariadicBlock,
8253      VariadicMethod,
8254      VariadicConstructor,
8255      VariadicDoesNotApply
8256    };
8257  
8258    VariadicCallType getVariadicCallType(FunctionDecl *FDecl,
8259                                         const FunctionProtoType *Proto,
8260                                         Expr *Fn);
8261  
8262    // Used for determining in which context a type is allowed to be passed to a
8263    // vararg function.
8264    enum VarArgKind {
8265      VAK_Valid,
8266      VAK_ValidInCXX11,
8267      VAK_Undefined,
8268      VAK_MSVCUndefined,
8269      VAK_Invalid
8270    };
8271  
8272    // Determines which VarArgKind fits an expression.
8273    VarArgKind isValidVarArgType(const QualType &Ty);
8274  
8275    /// Check to see if the given expression is a valid argument to a variadic
8276    /// function, issuing a diagnostic if not.
8277    void checkVariadicArgument(const Expr *E, VariadicCallType CT);
8278  
8279    /// Check to see if a given expression could have '.c_str()' called on it.
8280    bool hasCStrMethod(const Expr *E);
8281  
8282    /// GatherArgumentsForCall - Collector argument expressions for various
8283    /// form of call prototypes.
8284    bool GatherArgumentsForCall(SourceLocation CallLoc, FunctionDecl *FDecl,
8285                                const FunctionProtoType *Proto,
8286                                unsigned FirstParam, ArrayRef<Expr *> Args,
8287                                SmallVectorImpl<Expr *> &AllArgs,
8288                                VariadicCallType CallType = VariadicDoesNotApply,
8289                                bool AllowExplicit = false,
8290                                bool IsListInitialization = false);
8291  
8292    // DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but
8293    // will create a runtime trap if the resulting type is not a POD type.
8294    ExprResult DefaultVariadicArgumentPromotion(Expr *E, VariadicCallType CT,
8295                                                FunctionDecl *FDecl);
8296  
8297    // UsualArithmeticConversions - performs the UsualUnaryConversions on it's
8298    // operands and then handles various conversions that are common to binary
8299    // operators (C99 6.3.1.8). If both operands aren't arithmetic, this
8300    // routine returns the first non-arithmetic type found. The client is
8301    // responsible for emitting appropriate error diagnostics.
8302    QualType UsualArithmeticConversions(ExprResult &LHS, ExprResult &RHS,
8303                                        bool IsCompAssign = false);
8304  
8305    /// AssignConvertType - All of the 'assignment' semantic checks return this
8306    /// enum to indicate whether the assignment was allowed.  These checks are
8307    /// done for simple assignments, as well as initialization, return from
8308    /// function, argument passing, etc.  The query is phrased in terms of a
8309    /// source and destination type.
8310    enum AssignConvertType {
8311      /// Compatible - the types are compatible according to the standard.
8312      Compatible,
8313  
8314      /// PointerToInt - The assignment converts a pointer to an int, which we
8315      /// accept as an extension.
8316      PointerToInt,
8317  
8318      /// IntToPointer - The assignment converts an int to a pointer, which we
8319      /// accept as an extension.
8320      IntToPointer,
8321  
8322      /// FunctionVoidPointer - The assignment is between a function pointer and
8323      /// void*, which the standard doesn't allow, but we accept as an extension.
8324      FunctionVoidPointer,
8325  
8326      /// IncompatiblePointer - The assignment is between two pointers types that
8327      /// are not compatible, but we accept them as an extension.
8328      IncompatiblePointer,
8329  
8330      /// IncompatiblePointer - The assignment is between two pointers types which
8331      /// point to integers which have a different sign, but are otherwise
8332      /// identical. This is a subset of the above, but broken out because it's by
8333      /// far the most common case of incompatible pointers.
8334      IncompatiblePointerSign,
8335  
8336      /// CompatiblePointerDiscardsQualifiers - The assignment discards
8337      /// c/v/r qualifiers, which we accept as an extension.
8338      CompatiblePointerDiscardsQualifiers,
8339  
8340      /// IncompatiblePointerDiscardsQualifiers - The assignment
8341      /// discards qualifiers that we don't permit to be discarded,
8342      /// like address spaces.
8343      IncompatiblePointerDiscardsQualifiers,
8344  
8345      /// IncompatibleNestedPointerQualifiers - The assignment is between two
8346      /// nested pointer types, and the qualifiers other than the first two
8347      /// levels differ e.g. char ** -> const char **, but we accept them as an
8348      /// extension.
8349      IncompatibleNestedPointerQualifiers,
8350  
8351      /// IncompatibleVectors - The assignment is between two vector types that
8352      /// have the same size, which we accept as an extension.
8353      IncompatibleVectors,
8354  
8355      /// IntToBlockPointer - The assignment converts an int to a block
8356      /// pointer. We disallow this.
8357      IntToBlockPointer,
8358  
8359      /// IncompatibleBlockPointer - The assignment is between two block
8360      /// pointers types that are not compatible.
8361      IncompatibleBlockPointer,
8362  
8363      /// IncompatibleObjCQualifiedId - The assignment is between a qualified
8364      /// id type and something else (that is incompatible with it). For example,
8365      /// "id <XXX>" = "Foo *", where "Foo *" doesn't implement the XXX protocol.
8366      IncompatibleObjCQualifiedId,
8367  
8368      /// IncompatibleObjCWeakRef - Assigning a weak-unavailable object to an
8369      /// object with __weak qualifier.
8370      IncompatibleObjCWeakRef,
8371  
8372      /// Incompatible - We reject this conversion outright, it is invalid to
8373      /// represent it in the AST.
8374      Incompatible
8375    };
8376  
8377    /// DiagnoseAssignmentResult - Emit a diagnostic, if required, for the
8378    /// assignment conversion type specified by ConvTy.  This returns true if the
8379    /// conversion was invalid or false if the conversion was accepted.
8380    bool DiagnoseAssignmentResult(AssignConvertType ConvTy,
8381                                  SourceLocation Loc,
8382                                  QualType DstType, QualType SrcType,
8383                                  Expr *SrcExpr, AssignmentAction Action,
8384                                  bool *Complained = nullptr);
8385  
8386    /// IsValueInFlagEnum - Determine if a value is allowed as part of a flag
8387    /// enum. If AllowMask is true, then we also allow the complement of a valid
8388    /// value, to be used as a mask.
8389    bool IsValueInFlagEnum(const EnumDecl *ED, const llvm::APInt &Val,
8390                           bool AllowMask) const;
8391  
8392    /// DiagnoseAssignmentEnum - Warn if assignment to enum is a constant
8393    /// integer not in the range of enum values.
8394    void DiagnoseAssignmentEnum(QualType DstType, QualType SrcType,
8395                                Expr *SrcExpr);
8396  
8397    /// CheckAssignmentConstraints - Perform type checking for assignment,
8398    /// argument passing, variable initialization, and function return values.
8399    /// C99 6.5.16.
8400    AssignConvertType CheckAssignmentConstraints(SourceLocation Loc,
8401                                                 QualType LHSType,
8402                                                 QualType RHSType);
8403  
8404    /// Check assignment constraints and optionally prepare for a conversion of
8405    /// the RHS to the LHS type. The conversion is prepared for if ConvertRHS
8406    /// is true.
8407    AssignConvertType CheckAssignmentConstraints(QualType LHSType,
8408                                                 ExprResult &RHS,
8409                                                 CastKind &Kind,
8410                                                 bool ConvertRHS = true);
8411  
8412    // CheckSingleAssignmentConstraints - Currently used by
8413    // CheckAssignmentOperands, and ActOnReturnStmt. Prior to type checking,
8414    // this routine performs the default function/array converions, if ConvertRHS
8415    // is true.
8416    AssignConvertType CheckSingleAssignmentConstraints(QualType LHSType,
8417                                                       ExprResult &RHS,
8418                                                       bool Diagnose = true,
8419                                                       bool DiagnoseCFAudited = false,
8420                                                       bool ConvertRHS = true);
8421  
8422    // \brief If the lhs type is a transparent union, check whether we
8423    // can initialize the transparent union with the given expression.
8424    AssignConvertType CheckTransparentUnionArgumentConstraints(QualType ArgType,
8425                                                               ExprResult &RHS);
8426  
8427    bool IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType);
8428  
8429    bool CheckExceptionSpecCompatibility(Expr *From, QualType ToType);
8430  
8431    ExprResult PerformImplicitConversion(Expr *From, QualType ToType,
8432                                         AssignmentAction Action,
8433                                         bool AllowExplicit = false);
8434    ExprResult PerformImplicitConversion(Expr *From, QualType ToType,
8435                                         AssignmentAction Action,
8436                                         bool AllowExplicit,
8437                                         ImplicitConversionSequence& ICS);
8438    ExprResult PerformImplicitConversion(Expr *From, QualType ToType,
8439                                         const ImplicitConversionSequence& ICS,
8440                                         AssignmentAction Action,
8441                                         CheckedConversionKind CCK
8442                                            = CCK_ImplicitConversion);
8443    ExprResult PerformImplicitConversion(Expr *From, QualType ToType,
8444                                         const StandardConversionSequence& SCS,
8445                                         AssignmentAction Action,
8446                                         CheckedConversionKind CCK);
8447  
8448    /// the following "Check" methods will return a valid/converted QualType
8449    /// or a null QualType (indicating an error diagnostic was issued).
8450  
8451    /// type checking binary operators (subroutines of CreateBuiltinBinOp).
8452    QualType InvalidOperands(SourceLocation Loc, ExprResult &LHS,
8453                             ExprResult &RHS);
8454    QualType CheckPointerToMemberOperands( // C++ 5.5
8455      ExprResult &LHS, ExprResult &RHS, ExprValueKind &VK,
8456      SourceLocation OpLoc, bool isIndirect);
8457    QualType CheckMultiplyDivideOperands( // C99 6.5.5
8458      ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign,
8459      bool IsDivide);
8460    QualType CheckRemainderOperands( // C99 6.5.5
8461      ExprResult &LHS, ExprResult &RHS, SourceLocation Loc,
8462      bool IsCompAssign = false);
8463    QualType CheckAdditionOperands( // C99 6.5.6
8464      ExprResult &LHS, ExprResult &RHS, SourceLocation Loc,
8465      BinaryOperatorKind Opc, QualType* CompLHSTy = nullptr);
8466    QualType CheckSubtractionOperands( // C99 6.5.6
8467      ExprResult &LHS, ExprResult &RHS, SourceLocation Loc,
8468      QualType* CompLHSTy = nullptr);
8469    QualType CheckShiftOperands( // C99 6.5.7
8470      ExprResult &LHS, ExprResult &RHS, SourceLocation Loc,
8471      BinaryOperatorKind Opc, bool IsCompAssign = false);
8472    QualType CheckCompareOperands( // C99 6.5.8/9
8473      ExprResult &LHS, ExprResult &RHS, SourceLocation Loc,
8474      BinaryOperatorKind Opc, bool isRelational);
8475    QualType CheckBitwiseOperands( // C99 6.5.[10...12]
8476      ExprResult &LHS, ExprResult &RHS, SourceLocation Loc,
8477      bool IsCompAssign = false);
8478    QualType CheckLogicalOperands( // C99 6.5.[13,14]
8479      ExprResult &LHS, ExprResult &RHS, SourceLocation Loc,
8480      BinaryOperatorKind Opc);
8481    // CheckAssignmentOperands is used for both simple and compound assignment.
8482    // For simple assignment, pass both expressions and a null converted type.
8483    // For compound assignment, pass both expressions and the converted type.
8484    QualType CheckAssignmentOperands( // C99 6.5.16.[1,2]
8485      Expr *LHSExpr, ExprResult &RHS, SourceLocation Loc, QualType CompoundType);
8486  
8487    ExprResult checkPseudoObjectIncDec(Scope *S, SourceLocation OpLoc,
8488                                       UnaryOperatorKind Opcode, Expr *Op);
8489    ExprResult checkPseudoObjectAssignment(Scope *S, SourceLocation OpLoc,
8490                                           BinaryOperatorKind Opcode,
8491                                           Expr *LHS, Expr *RHS);
8492    ExprResult checkPseudoObjectRValue(Expr *E);
8493    Expr *recreateSyntacticForm(PseudoObjectExpr *E);
8494  
8495    QualType CheckConditionalOperands( // C99 6.5.15
8496      ExprResult &Cond, ExprResult &LHS, ExprResult &RHS,
8497      ExprValueKind &VK, ExprObjectKind &OK, SourceLocation QuestionLoc);
8498    QualType CXXCheckConditionalOperands( // C++ 5.16
8499      ExprResult &cond, ExprResult &lhs, ExprResult &rhs,
8500      ExprValueKind &VK, ExprObjectKind &OK, SourceLocation questionLoc);
8501    QualType FindCompositePointerType(SourceLocation Loc, Expr *&E1, Expr *&E2,
8502                                      bool *NonStandardCompositeType = nullptr);
8503    QualType FindCompositePointerType(SourceLocation Loc,
8504                                      ExprResult &E1, ExprResult &E2,
8505                                      bool *NonStandardCompositeType = nullptr) {
8506      Expr *E1Tmp = E1.get(), *E2Tmp = E2.get();
8507      QualType Composite = FindCompositePointerType(Loc, E1Tmp, E2Tmp,
8508                                                    NonStandardCompositeType);
8509      E1 = E1Tmp;
8510      E2 = E2Tmp;
8511      return Composite;
8512    }
8513  
8514    QualType FindCompositeObjCPointerType(ExprResult &LHS, ExprResult &RHS,
8515                                          SourceLocation QuestionLoc);
8516  
8517    bool DiagnoseConditionalForNull(Expr *LHSExpr, Expr *RHSExpr,
8518                                    SourceLocation QuestionLoc);
8519  
8520    void DiagnoseAlwaysNonNullPointer(Expr *E,
8521                                      Expr::NullPointerConstantKind NullType,
8522                                      bool IsEqual, SourceRange Range);
8523  
8524    /// type checking for vector binary operators.
8525    QualType CheckVectorOperands(ExprResult &LHS, ExprResult &RHS,
8526                                 SourceLocation Loc, bool IsCompAssign,
8527                                 bool AllowBothBool, bool AllowBoolConversion);
8528    QualType GetSignedVectorType(QualType V);
8529    QualType CheckVectorCompareOperands(ExprResult &LHS, ExprResult &RHS,
8530                                        SourceLocation Loc, bool isRelational);
8531    QualType CheckVectorLogicalOperands(ExprResult &LHS, ExprResult &RHS,
8532                                        SourceLocation Loc);
8533  
8534    bool areLaxCompatibleVectorTypes(QualType srcType, QualType destType);
8535    bool isLaxVectorConversion(QualType srcType, QualType destType);
8536  
8537    /// type checking declaration initializers (C99 6.7.8)
8538    bool CheckForConstantInitializer(Expr *e, QualType t);
8539  
8540    // type checking C++ declaration initializers (C++ [dcl.init]).
8541  
8542    /// ReferenceCompareResult - Expresses the result of comparing two
8543    /// types (cv1 T1 and cv2 T2) to determine their compatibility for the
8544    /// purposes of initialization by reference (C++ [dcl.init.ref]p4).
8545    enum ReferenceCompareResult {
8546      /// Ref_Incompatible - The two types are incompatible, so direct
8547      /// reference binding is not possible.
8548      Ref_Incompatible = 0,
8549      /// Ref_Related - The two types are reference-related, which means
8550      /// that their unqualified forms (T1 and T2) are either the same
8551      /// or T1 is a base class of T2.
8552      Ref_Related,
8553      /// Ref_Compatible_With_Added_Qualification - The two types are
8554      /// reference-compatible with added qualification, meaning that
8555      /// they are reference-compatible and the qualifiers on T1 (cv1)
8556      /// are greater than the qualifiers on T2 (cv2).
8557      Ref_Compatible_With_Added_Qualification,
8558      /// Ref_Compatible - The two types are reference-compatible and
8559      /// have equivalent qualifiers (cv1 == cv2).
8560      Ref_Compatible
8561    };
8562  
8563    ReferenceCompareResult CompareReferenceRelationship(SourceLocation Loc,
8564                                                        QualType T1, QualType T2,
8565                                                        bool &DerivedToBase,
8566                                                        bool &ObjCConversion,
8567                                                  bool &ObjCLifetimeConversion);
8568  
8569    ExprResult checkUnknownAnyCast(SourceRange TypeRange, QualType CastType,
8570                                   Expr *CastExpr, CastKind &CastKind,
8571                                   ExprValueKind &VK, CXXCastPath &Path);
8572  
8573    /// \brief Force an expression with unknown-type to an expression of the
8574    /// given type.
8575    ExprResult forceUnknownAnyToType(Expr *E, QualType ToType);
8576  
8577    /// \brief Type-check an expression that's being passed to an
8578    /// __unknown_anytype parameter.
8579    ExprResult checkUnknownAnyArg(SourceLocation callLoc,
8580                                  Expr *result, QualType &paramType);
8581  
8582    // CheckVectorCast - check type constraints for vectors.
8583    // Since vectors are an extension, there are no C standard reference for this.
8584    // We allow casting between vectors and integer datatypes of the same size.
8585    // returns true if the cast is invalid
8586    bool CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty,
8587                         CastKind &Kind);
8588  
8589    // CheckExtVectorCast - check type constraints for extended vectors.
8590    // Since vectors are an extension, there are no C standard reference for this.
8591    // We allow casting between vectors and integer datatypes of the same size,
8592    // or vectors and the element type of that vector.
8593    // returns the cast expr
8594    ExprResult CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *CastExpr,
8595                                  CastKind &Kind);
8596  
8597    ExprResult BuildCXXFunctionalCastExpr(TypeSourceInfo *TInfo,
8598                                          SourceLocation LParenLoc,
8599                                          Expr *CastExpr,
8600                                          SourceLocation RParenLoc);
8601  
8602    enum ARCConversionResult { ACR_okay, ACR_unbridged };
8603  
8604    /// \brief Checks for invalid conversions and casts between
8605    /// retainable pointers and other pointer kinds.
8606    ARCConversionResult CheckObjCARCConversion(SourceRange castRange,
8607                                               QualType castType, Expr *&op,
8608                                               CheckedConversionKind CCK,
8609                                               bool DiagnoseCFAudited = false,
8610                                               BinaryOperatorKind Opc = BO_PtrMemD
8611                                               );
8612  
8613    Expr *stripARCUnbridgedCast(Expr *e);
8614    void diagnoseARCUnbridgedCast(Expr *e);
8615  
8616    bool CheckObjCARCUnavailableWeakConversion(QualType castType,
8617                                               QualType ExprType);
8618  
8619    /// checkRetainCycles - Check whether an Objective-C message send
8620    /// might create an obvious retain cycle.
8621    void checkRetainCycles(ObjCMessageExpr *msg);
8622    void checkRetainCycles(Expr *receiver, Expr *argument);
8623    void checkRetainCycles(VarDecl *Var, Expr *Init);
8624  
8625    /// checkUnsafeAssigns - Check whether +1 expr is being assigned
8626    /// to weak/__unsafe_unretained type.
8627    bool checkUnsafeAssigns(SourceLocation Loc, QualType LHS, Expr *RHS);
8628  
8629    /// checkUnsafeExprAssigns - Check whether +1 expr is being assigned
8630    /// to weak/__unsafe_unretained expression.
8631    void checkUnsafeExprAssigns(SourceLocation Loc, Expr *LHS, Expr *RHS);
8632  
8633    /// CheckMessageArgumentTypes - Check types in an Obj-C message send.
8634    /// \param Method - May be null.
8635    /// \param [out] ReturnType - The return type of the send.
8636    /// \return true iff there were any incompatible types.
8637    bool CheckMessageArgumentTypes(QualType ReceiverType,
8638                                   MultiExprArg Args, Selector Sel,
8639                                   ArrayRef<SourceLocation> SelectorLocs,
8640                                   ObjCMethodDecl *Method, bool isClassMessage,
8641                                   bool isSuperMessage,
8642                                   SourceLocation lbrac, SourceLocation rbrac,
8643                                   SourceRange RecRange,
8644                                   QualType &ReturnType, ExprValueKind &VK);
8645  
8646    /// \brief Determine the result of a message send expression based on
8647    /// the type of the receiver, the method expected to receive the message,
8648    /// and the form of the message send.
8649    QualType getMessageSendResultType(QualType ReceiverType,
8650                                      ObjCMethodDecl *Method,
8651                                      bool isClassMessage, bool isSuperMessage);
8652  
8653    /// \brief If the given expression involves a message send to a method
8654    /// with a related result type, emit a note describing what happened.
8655    void EmitRelatedResultTypeNote(const Expr *E);
8656  
8657    /// \brief Given that we had incompatible pointer types in a return
8658    /// statement, check whether we're in a method with a related result
8659    /// type, and if so, emit a note describing what happened.
8660    void EmitRelatedResultTypeNoteForReturn(QualType destType);
8661  
8662    /// CheckBooleanCondition - Diagnose problems involving the use of
8663    /// the given expression as a boolean condition (e.g. in an if
8664    /// statement).  Also performs the standard function and array
8665    /// decays, possibly changing the input variable.
8666    ///
8667    /// \param Loc - A location associated with the condition, e.g. the
8668    /// 'if' keyword.
8669    /// \return true iff there were any errors
8670    ExprResult CheckBooleanCondition(Expr *E, SourceLocation Loc);
8671  
8672    ExprResult ActOnBooleanCondition(Scope *S, SourceLocation Loc,
8673                                     Expr *SubExpr);
8674  
8675    /// DiagnoseAssignmentAsCondition - Given that an expression is
8676    /// being used as a boolean condition, warn if it's an assignment.
8677    void DiagnoseAssignmentAsCondition(Expr *E);
8678  
8679    /// \brief Redundant parentheses over an equality comparison can indicate
8680    /// that the user intended an assignment used as condition.
8681    void DiagnoseEqualityWithExtraParens(ParenExpr *ParenE);
8682  
8683    /// CheckCXXBooleanCondition - Returns true if conversion to bool is invalid.
8684    ExprResult CheckCXXBooleanCondition(Expr *CondExpr);
8685  
8686    /// ConvertIntegerToTypeWarnOnOverflow - Convert the specified APInt to have
8687    /// the specified width and sign.  If an overflow occurs, detect it and emit
8688    /// the specified diagnostic.
8689    void ConvertIntegerToTypeWarnOnOverflow(llvm::APSInt &OldVal,
8690                                            unsigned NewWidth, bool NewSign,
8691                                            SourceLocation Loc, unsigned DiagID);
8692  
8693    /// Checks that the Objective-C declaration is declared in the global scope.
8694    /// Emits an error and marks the declaration as invalid if it's not declared
8695    /// in the global scope.
8696    bool CheckObjCDeclScope(Decl *D);
8697  
8698    /// \brief Abstract base class used for diagnosing integer constant
8699    /// expression violations.
8700    class VerifyICEDiagnoser {
8701    public:
8702      bool Suppress;
8703  
Suppress(Suppress)8704      VerifyICEDiagnoser(bool Suppress = false) : Suppress(Suppress) { }
8705  
8706      virtual void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) =0;
8707      virtual void diagnoseFold(Sema &S, SourceLocation Loc, SourceRange SR);
~VerifyICEDiagnoser()8708      virtual ~VerifyICEDiagnoser() { }
8709    };
8710  
8711    /// VerifyIntegerConstantExpression - Verifies that an expression is an ICE,
8712    /// and reports the appropriate diagnostics. Returns false on success.
8713    /// Can optionally return the value of the expression.
8714    ExprResult VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
8715                                               VerifyICEDiagnoser &Diagnoser,
8716                                               bool AllowFold = true);
8717    ExprResult VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
8718                                               unsigned DiagID,
8719                                               bool AllowFold = true);
8720    ExprResult VerifyIntegerConstantExpression(Expr *E,
8721                                               llvm::APSInt *Result = nullptr);
8722  
8723    /// VerifyBitField - verifies that a bit field expression is an ICE and has
8724    /// the correct width, and that the field type is valid.
8725    /// Returns false on success.
8726    /// Can optionally return whether the bit-field is of width 0
8727    ExprResult VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName,
8728                              QualType FieldTy, bool IsMsStruct,
8729                              Expr *BitWidth, bool *ZeroWidth = nullptr);
8730  
8731    enum CUDAFunctionTarget {
8732      CFT_Device,
8733      CFT_Global,
8734      CFT_Host,
8735      CFT_HostDevice,
8736      CFT_InvalidTarget
8737    };
8738  
8739    CUDAFunctionTarget IdentifyCUDATarget(const FunctionDecl *D);
8740  
8741    enum CUDAFunctionPreference {
8742      CFP_Never,      // Invalid caller/callee combination.
8743      CFP_LastResort, // Lowest priority. Only in effect if
8744                      // LangOpts.CUDADisableTargetCallChecks is true.
8745      CFP_Fallback,   // Low priority caller/callee combination
8746      CFP_Best,       // Preferred caller/callee combination
8747    };
8748  
8749    /// Identifies relative preference of a given Caller/Callee
8750    /// combination, based on their host/device attributes.
8751    /// \param Caller function which needs address of \p Callee.
8752    ///               nullptr in case of global context.
8753    /// \param Callee target function
8754    ///
8755    /// \returns preference value for particular Caller/Callee combination.
8756    CUDAFunctionPreference IdentifyCUDAPreference(const FunctionDecl *Caller,
8757                                                  const FunctionDecl *Callee);
8758  
8759    bool CheckCUDATarget(const FunctionDecl *Caller, const FunctionDecl *Callee);
8760  
8761    /// Finds a function in \p Matches with highest calling priority
8762    /// from \p Caller context and erases all functions with lower
8763    /// calling priority.
8764    void EraseUnwantedCUDAMatches(const FunctionDecl *Caller,
8765                                  SmallVectorImpl<FunctionDecl *> &Matches);
8766    void EraseUnwantedCUDAMatches(const FunctionDecl *Caller,
8767                                  SmallVectorImpl<DeclAccessPair> &Matches);
8768    void EraseUnwantedCUDAMatches(
8769        const FunctionDecl *Caller,
8770        SmallVectorImpl<std::pair<DeclAccessPair, FunctionDecl *>> &Matches);
8771  
8772    /// Given a implicit special member, infer its CUDA target from the
8773    /// calls it needs to make to underlying base/field special members.
8774    /// \param ClassDecl the class for which the member is being created.
8775    /// \param CSM the kind of special member.
8776    /// \param MemberDecl the special member itself.
8777    /// \param ConstRHS true if this is a copy operation with a const object on
8778    ///        its RHS.
8779    /// \param Diagnose true if this call should emit diagnostics.
8780    /// \return true if there was an error inferring.
8781    /// The result of this call is implicit CUDA target attribute(s) attached to
8782    /// the member declaration.
8783    bool inferCUDATargetForImplicitSpecialMember(CXXRecordDecl *ClassDecl,
8784                                                 CXXSpecialMember CSM,
8785                                                 CXXMethodDecl *MemberDecl,
8786                                                 bool ConstRHS,
8787                                                 bool Diagnose);
8788  
8789    /// \name Code completion
8790    //@{
8791    /// \brief Describes the context in which code completion occurs.
8792    enum ParserCompletionContext {
8793      /// \brief Code completion occurs at top-level or namespace context.
8794      PCC_Namespace,
8795      /// \brief Code completion occurs within a class, struct, or union.
8796      PCC_Class,
8797      /// \brief Code completion occurs within an Objective-C interface, protocol,
8798      /// or category.
8799      PCC_ObjCInterface,
8800      /// \brief Code completion occurs within an Objective-C implementation or
8801      /// category implementation
8802      PCC_ObjCImplementation,
8803      /// \brief Code completion occurs within the list of instance variables
8804      /// in an Objective-C interface, protocol, category, or implementation.
8805      PCC_ObjCInstanceVariableList,
8806      /// \brief Code completion occurs following one or more template
8807      /// headers.
8808      PCC_Template,
8809      /// \brief Code completion occurs following one or more template
8810      /// headers within a class.
8811      PCC_MemberTemplate,
8812      /// \brief Code completion occurs within an expression.
8813      PCC_Expression,
8814      /// \brief Code completion occurs within a statement, which may
8815      /// also be an expression or a declaration.
8816      PCC_Statement,
8817      /// \brief Code completion occurs at the beginning of the
8818      /// initialization statement (or expression) in a for loop.
8819      PCC_ForInit,
8820      /// \brief Code completion occurs within the condition of an if,
8821      /// while, switch, or for statement.
8822      PCC_Condition,
8823      /// \brief Code completion occurs within the body of a function on a
8824      /// recovery path, where we do not have a specific handle on our position
8825      /// in the grammar.
8826      PCC_RecoveryInFunction,
8827      /// \brief Code completion occurs where only a type is permitted.
8828      PCC_Type,
8829      /// \brief Code completion occurs in a parenthesized expression, which
8830      /// might also be a type cast.
8831      PCC_ParenthesizedExpression,
8832      /// \brief Code completion occurs within a sequence of declaration
8833      /// specifiers within a function, method, or block.
8834      PCC_LocalDeclarationSpecifiers
8835    };
8836  
8837    void CodeCompleteModuleImport(SourceLocation ImportLoc, ModuleIdPath Path);
8838    void CodeCompleteOrdinaryName(Scope *S,
8839                                  ParserCompletionContext CompletionContext);
8840    void CodeCompleteDeclSpec(Scope *S, DeclSpec &DS,
8841                              bool AllowNonIdentifiers,
8842                              bool AllowNestedNameSpecifiers);
8843  
8844    struct CodeCompleteExpressionData;
8845    void CodeCompleteExpression(Scope *S,
8846                                const CodeCompleteExpressionData &Data);
8847    void CodeCompleteMemberReferenceExpr(Scope *S, Expr *Base,
8848                                         SourceLocation OpLoc,
8849                                         bool IsArrow);
8850    void CodeCompletePostfixExpression(Scope *S, ExprResult LHS);
8851    void CodeCompleteTag(Scope *S, unsigned TagSpec);
8852    void CodeCompleteTypeQualifiers(DeclSpec &DS);
8853    void CodeCompleteCase(Scope *S);
8854    void CodeCompleteCall(Scope *S, Expr *Fn, ArrayRef<Expr *> Args);
8855    void CodeCompleteConstructor(Scope *S, QualType Type, SourceLocation Loc,
8856                                 ArrayRef<Expr *> Args);
8857    void CodeCompleteInitializer(Scope *S, Decl *D);
8858    void CodeCompleteReturn(Scope *S);
8859    void CodeCompleteAfterIf(Scope *S);
8860    void CodeCompleteAssignmentRHS(Scope *S, Expr *LHS);
8861  
8862    void CodeCompleteQualifiedId(Scope *S, CXXScopeSpec &SS,
8863                                 bool EnteringContext);
8864    void CodeCompleteUsing(Scope *S);
8865    void CodeCompleteUsingDirective(Scope *S);
8866    void CodeCompleteNamespaceDecl(Scope *S);
8867    void CodeCompleteNamespaceAliasDecl(Scope *S);
8868    void CodeCompleteOperatorName(Scope *S);
8869    void CodeCompleteConstructorInitializer(
8870                                  Decl *Constructor,
8871                                  ArrayRef<CXXCtorInitializer *> Initializers);
8872  
8873    void CodeCompleteLambdaIntroducer(Scope *S, LambdaIntroducer &Intro,
8874                                      bool AfterAmpersand);
8875  
8876    void CodeCompleteObjCAtDirective(Scope *S);
8877    void CodeCompleteObjCAtVisibility(Scope *S);
8878    void CodeCompleteObjCAtStatement(Scope *S);
8879    void CodeCompleteObjCAtExpression(Scope *S);
8880    void CodeCompleteObjCPropertyFlags(Scope *S, ObjCDeclSpec &ODS);
8881    void CodeCompleteObjCPropertyGetter(Scope *S);
8882    void CodeCompleteObjCPropertySetter(Scope *S);
8883    void CodeCompleteObjCPassingType(Scope *S, ObjCDeclSpec &DS,
8884                                     bool IsParameter);
8885    void CodeCompleteObjCMessageReceiver(Scope *S);
8886    void CodeCompleteObjCSuperMessage(Scope *S, SourceLocation SuperLoc,
8887                                      ArrayRef<IdentifierInfo *> SelIdents,
8888                                      bool AtArgumentExpression);
8889    void CodeCompleteObjCClassMessage(Scope *S, ParsedType Receiver,
8890                                      ArrayRef<IdentifierInfo *> SelIdents,
8891                                      bool AtArgumentExpression,
8892                                      bool IsSuper = false);
8893    void CodeCompleteObjCInstanceMessage(Scope *S, Expr *Receiver,
8894                                         ArrayRef<IdentifierInfo *> SelIdents,
8895                                         bool AtArgumentExpression,
8896                                         ObjCInterfaceDecl *Super = nullptr);
8897    void CodeCompleteObjCForCollection(Scope *S,
8898                                       DeclGroupPtrTy IterationVar);
8899    void CodeCompleteObjCSelector(Scope *S,
8900                                  ArrayRef<IdentifierInfo *> SelIdents);
8901    void CodeCompleteObjCProtocolReferences(IdentifierLocPair *Protocols,
8902                                            unsigned NumProtocols);
8903    void CodeCompleteObjCProtocolDecl(Scope *S);
8904    void CodeCompleteObjCInterfaceDecl(Scope *S);
8905    void CodeCompleteObjCSuperclass(Scope *S,
8906                                    IdentifierInfo *ClassName,
8907                                    SourceLocation ClassNameLoc);
8908    void CodeCompleteObjCImplementationDecl(Scope *S);
8909    void CodeCompleteObjCInterfaceCategory(Scope *S,
8910                                           IdentifierInfo *ClassName,
8911                                           SourceLocation ClassNameLoc);
8912    void CodeCompleteObjCImplementationCategory(Scope *S,
8913                                                IdentifierInfo *ClassName,
8914                                                SourceLocation ClassNameLoc);
8915    void CodeCompleteObjCPropertyDefinition(Scope *S);
8916    void CodeCompleteObjCPropertySynthesizeIvar(Scope *S,
8917                                                IdentifierInfo *PropertyName);
8918    void CodeCompleteObjCMethodDecl(Scope *S,
8919                                    bool IsInstanceMethod,
8920                                    ParsedType ReturnType);
8921    void CodeCompleteObjCMethodDeclSelector(Scope *S,
8922                                            bool IsInstanceMethod,
8923                                            bool AtParameterName,
8924                                            ParsedType ReturnType,
8925                                            ArrayRef<IdentifierInfo *> SelIdents);
8926    void CodeCompletePreprocessorDirective(bool InConditional);
8927    void CodeCompleteInPreprocessorConditionalExclusion(Scope *S);
8928    void CodeCompletePreprocessorMacroName(bool IsDefinition);
8929    void CodeCompletePreprocessorExpression();
8930    void CodeCompletePreprocessorMacroArgument(Scope *S,
8931                                               IdentifierInfo *Macro,
8932                                               MacroInfo *MacroInfo,
8933                                               unsigned Argument);
8934    void CodeCompleteNaturalLanguage();
8935    void GatherGlobalCodeCompletions(CodeCompletionAllocator &Allocator,
8936                                     CodeCompletionTUInfo &CCTUInfo,
8937                    SmallVectorImpl<CodeCompletionResult> &Results);
8938    //@}
8939  
8940    //===--------------------------------------------------------------------===//
8941    // Extra semantic analysis beyond the C type system
8942  
8943  public:
8944    SourceLocation getLocationOfStringLiteralByte(const StringLiteral *SL,
8945                                                  unsigned ByteNo) const;
8946  
8947  private:
8948    void CheckArrayAccess(const Expr *BaseExpr, const Expr *IndexExpr,
8949                          const ArraySubscriptExpr *ASE=nullptr,
8950                          bool AllowOnePastEnd=true, bool IndexNegated=false);
8951    void CheckArrayAccess(const Expr *E);
8952    // Used to grab the relevant information from a FormatAttr and a
8953    // FunctionDeclaration.
8954    struct FormatStringInfo {
8955      unsigned FormatIdx;
8956      unsigned FirstDataArg;
8957      bool HasVAListArg;
8958    };
8959  
8960    static bool getFormatStringInfo(const FormatAttr *Format, bool IsCXXMember,
8961                                    FormatStringInfo *FSI);
8962    bool CheckFunctionCall(FunctionDecl *FDecl, CallExpr *TheCall,
8963                           const FunctionProtoType *Proto);
8964    bool CheckObjCMethodCall(ObjCMethodDecl *Method, SourceLocation loc,
8965                             ArrayRef<const Expr *> Args);
8966    bool CheckPointerCall(NamedDecl *NDecl, CallExpr *TheCall,
8967                          const FunctionProtoType *Proto);
8968    bool CheckOtherCall(CallExpr *TheCall, const FunctionProtoType *Proto);
8969    void CheckConstructorCall(FunctionDecl *FDecl,
8970                              ArrayRef<const Expr *> Args,
8971                              const FunctionProtoType *Proto,
8972                              SourceLocation Loc);
8973  
8974    void checkCall(NamedDecl *FDecl, const FunctionProtoType *Proto,
8975                   ArrayRef<const Expr *> Args, bool IsMemberFunction,
8976                   SourceLocation Loc, SourceRange Range,
8977                   VariadicCallType CallType);
8978  
8979    bool CheckObjCString(Expr *Arg);
8980  
8981    ExprResult CheckBuiltinFunctionCall(FunctionDecl *FDecl,
8982                                        unsigned BuiltinID, CallExpr *TheCall);
8983  
8984    bool CheckARMBuiltinExclusiveCall(unsigned BuiltinID, CallExpr *TheCall,
8985                                      unsigned MaxWidth);
8986    bool CheckNeonBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
8987    bool CheckARMBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
8988  
8989    bool CheckAArch64BuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
8990    bool CheckMipsBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
8991    bool CheckSystemZBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
8992    bool CheckX86BuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
8993    bool CheckPPCBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
8994  
8995    bool SemaBuiltinVAStartImpl(CallExpr *TheCall);
8996    bool SemaBuiltinVAStart(CallExpr *TheCall);
8997    bool SemaBuiltinMSVAStart(CallExpr *TheCall);
8998    bool SemaBuiltinVAStartARM(CallExpr *Call);
8999    bool SemaBuiltinUnorderedCompare(CallExpr *TheCall);
9000    bool SemaBuiltinFPClassification(CallExpr *TheCall, unsigned NumArgs);
9001  
9002  public:
9003    // Used by C++ template instantiation.
9004    ExprResult SemaBuiltinShuffleVector(CallExpr *TheCall);
9005    ExprResult SemaConvertVectorExpr(Expr *E, TypeSourceInfo *TInfo,
9006                                     SourceLocation BuiltinLoc,
9007                                     SourceLocation RParenLoc);
9008  
9009  private:
9010    bool SemaBuiltinPrefetch(CallExpr *TheCall);
9011    bool SemaBuiltinAssume(CallExpr *TheCall);
9012    bool SemaBuiltinAssumeAligned(CallExpr *TheCall);
9013    bool SemaBuiltinLongjmp(CallExpr *TheCall);
9014    bool SemaBuiltinSetjmp(CallExpr *TheCall);
9015    ExprResult SemaBuiltinAtomicOverloaded(ExprResult TheCallResult);
9016    ExprResult SemaBuiltinNontemporalOverloaded(ExprResult TheCallResult);
9017    ExprResult SemaAtomicOpsOverloaded(ExprResult TheCallResult,
9018                                       AtomicExpr::AtomicOp Op);
9019    bool SemaBuiltinConstantArg(CallExpr *TheCall, int ArgNum,
9020                                llvm::APSInt &Result);
9021    bool SemaBuiltinConstantArgRange(CallExpr *TheCall, int ArgNum,
9022                                     int Low, int High);
9023    bool SemaBuiltinARMSpecialReg(unsigned BuiltinID, CallExpr *TheCall,
9024                                  int ArgNum, unsigned ExpectedFieldNum,
9025                                  bool AllowName);
9026  public:
9027    enum FormatStringType {
9028      FST_Scanf,
9029      FST_Printf,
9030      FST_NSString,
9031      FST_Strftime,
9032      FST_Strfmon,
9033      FST_Kprintf,
9034      FST_FreeBSDKPrintf,
9035      FST_OSTrace,
9036      FST_Unknown
9037    };
9038    static FormatStringType GetFormatStringType(const FormatAttr *Format);
9039  
9040    void CheckFormatString(const StringLiteral *FExpr, const Expr *OrigFormatExpr,
9041                           ArrayRef<const Expr *> Args, bool HasVAListArg,
9042                           unsigned format_idx, unsigned firstDataArg,
9043                           FormatStringType Type, bool inFunctionCall,
9044                           VariadicCallType CallType,
9045                           llvm::SmallBitVector &CheckedVarArgs);
9046  
9047    bool FormatStringHasSArg(const StringLiteral *FExpr);
9048  
9049    static bool GetFormatNSStringIdx(const FormatAttr *Format, unsigned &Idx);
9050  
9051  private:
9052    bool CheckFormatArguments(const FormatAttr *Format,
9053                              ArrayRef<const Expr *> Args,
9054                              bool IsCXXMember,
9055                              VariadicCallType CallType,
9056                              SourceLocation Loc, SourceRange Range,
9057                              llvm::SmallBitVector &CheckedVarArgs);
9058    bool CheckFormatArguments(ArrayRef<const Expr *> Args,
9059                              bool HasVAListArg, unsigned format_idx,
9060                              unsigned firstDataArg, FormatStringType Type,
9061                              VariadicCallType CallType,
9062                              SourceLocation Loc, SourceRange range,
9063                              llvm::SmallBitVector &CheckedVarArgs);
9064  
9065    void CheckAbsoluteValueFunction(const CallExpr *Call,
9066                                    const FunctionDecl *FDecl,
9067                                    IdentifierInfo *FnInfo);
9068  
9069    void CheckMemaccessArguments(const CallExpr *Call,
9070                                 unsigned BId,
9071                                 IdentifierInfo *FnName);
9072  
9073    void CheckStrlcpycatArguments(const CallExpr *Call,
9074                                  IdentifierInfo *FnName);
9075  
9076    void CheckStrncatArguments(const CallExpr *Call,
9077                               IdentifierInfo *FnName);
9078  
9079    void CheckReturnValExpr(Expr *RetValExp, QualType lhsType,
9080                            SourceLocation ReturnLoc,
9081                            bool isObjCMethod = false,
9082                            const AttrVec *Attrs = nullptr,
9083                            const FunctionDecl *FD = nullptr);
9084  
9085    void CheckFloatComparison(SourceLocation Loc, Expr* LHS, Expr* RHS);
9086    void CheckImplicitConversions(Expr *E, SourceLocation CC = SourceLocation());
9087    void CheckBoolLikeConversion(Expr *E, SourceLocation CC);
9088    void CheckForIntOverflow(Expr *E);
9089    void CheckUnsequencedOperations(Expr *E);
9090  
9091    /// \brief Perform semantic checks on a completed expression. This will either
9092    /// be a full-expression or a default argument expression.
9093    void CheckCompletedExpr(Expr *E, SourceLocation CheckLoc = SourceLocation(),
9094                            bool IsConstexpr = false);
9095  
9096    void CheckBitFieldInitialization(SourceLocation InitLoc, FieldDecl *Field,
9097                                     Expr *Init);
9098  
9099    /// \brief Check if the given expression contains 'break' or 'continue'
9100    /// statement that produces control flow different from GCC.
9101    void CheckBreakContinueBinding(Expr *E);
9102  
9103    /// \brief Check whether receiver is mutable ObjC container which
9104    /// attempts to add itself into the container
9105    void CheckObjCCircularContainer(ObjCMessageExpr *Message);
9106  
9107    void AnalyzeDeleteExprMismatch(const CXXDeleteExpr *DE);
9108    void AnalyzeDeleteExprMismatch(FieldDecl *Field, SourceLocation DeleteLoc,
9109                                   bool DeleteWasArrayForm);
9110  public:
9111    /// \brief Register a magic integral constant to be used as a type tag.
9112    void RegisterTypeTagForDatatype(const IdentifierInfo *ArgumentKind,
9113                                    uint64_t MagicValue, QualType Type,
9114                                    bool LayoutCompatible, bool MustBeNull);
9115  
9116    struct TypeTagData {
TypeTagDataTypeTagData9117      TypeTagData() {}
9118  
TypeTagDataTypeTagData9119      TypeTagData(QualType Type, bool LayoutCompatible, bool MustBeNull) :
9120          Type(Type), LayoutCompatible(LayoutCompatible),
9121          MustBeNull(MustBeNull)
9122      {}
9123  
9124      QualType Type;
9125  
9126      /// If true, \c Type should be compared with other expression's types for
9127      /// layout-compatibility.
9128      unsigned LayoutCompatible : 1;
9129      unsigned MustBeNull : 1;
9130    };
9131  
9132    /// A pair of ArgumentKind identifier and magic value.  This uniquely
9133    /// identifies the magic value.
9134    typedef std::pair<const IdentifierInfo *, uint64_t> TypeTagMagicValue;
9135  
9136  private:
9137    /// \brief A map from magic value to type information.
9138    std::unique_ptr<llvm::DenseMap<TypeTagMagicValue, TypeTagData>>
9139        TypeTagForDatatypeMagicValues;
9140  
9141    /// \brief Peform checks on a call of a function with argument_with_type_tag
9142    /// or pointer_with_type_tag attributes.
9143    void CheckArgumentWithTypeTag(const ArgumentWithTypeTagAttr *Attr,
9144                                  const Expr * const *ExprArgs);
9145  
9146    /// \brief The parser's current scope.
9147    ///
9148    /// The parser maintains this state here.
9149    Scope *CurScope;
9150  
9151    mutable IdentifierInfo *Ident_super;
9152    mutable IdentifierInfo *Ident___float128;
9153  
9154    /// Nullability type specifiers.
9155    IdentifierInfo *Ident__Nonnull = nullptr;
9156    IdentifierInfo *Ident__Nullable = nullptr;
9157    IdentifierInfo *Ident__Null_unspecified = nullptr;
9158  
9159    IdentifierInfo *Ident_NSError = nullptr;
9160  
9161  protected:
9162    friend class Parser;
9163    friend class InitializationSequence;
9164    friend class ASTReader;
9165    friend class ASTDeclReader;
9166    friend class ASTWriter;
9167  
9168  public:
9169    /// Retrieve the keyword associated
9170    IdentifierInfo *getNullabilityKeyword(NullabilityKind nullability);
9171  
9172    /// The struct behind the CFErrorRef pointer.
9173    RecordDecl *CFError = nullptr;
9174  
9175    /// Retrieve the identifier "NSError".
9176    IdentifierInfo *getNSErrorIdent();
9177  
9178    /// \brief Retrieve the parser's current scope.
9179    ///
9180    /// This routine must only be used when it is certain that semantic analysis
9181    /// and the parser are in precisely the same context, which is not the case
9182    /// when, e.g., we are performing any kind of template instantiation.
9183    /// Therefore, the only safe places to use this scope are in the parser
9184    /// itself and in routines directly invoked from the parser and *never* from
9185    /// template substitution or instantiation.
getCurScope()9186    Scope *getCurScope() const { return CurScope; }
9187  
incrementMSManglingNumber()9188    void incrementMSManglingNumber() const {
9189      return CurScope->incrementMSManglingNumber();
9190    }
9191  
9192    IdentifierInfo *getSuperIdentifier() const;
9193    IdentifierInfo *getFloat128Identifier() const;
9194  
9195    Decl *getObjCDeclContext() const;
9196  
getCurLexicalContext()9197    DeclContext *getCurLexicalContext() const {
9198      return OriginalLexicalContext ? OriginalLexicalContext : CurContext;
9199    }
9200  
9201    AvailabilityResult getCurContextAvailability() const;
9202  
getCurObjCLexicalContext()9203    const DeclContext *getCurObjCLexicalContext() const {
9204      const DeclContext *DC = getCurLexicalContext();
9205      // A category implicitly has the attribute of the interface.
9206      if (const ObjCCategoryDecl *CatD = dyn_cast<ObjCCategoryDecl>(DC))
9207        DC = CatD->getClassInterface();
9208      return DC;
9209    }
9210  
9211    /// \brief To be used for checking whether the arguments being passed to
9212    /// function exceeds the number of parameters expected for it.
9213    static bool TooManyArguments(size_t NumParams, size_t NumArgs,
9214                                 bool PartialOverloading = false) {
9215      // We check whether we're just after a comma in code-completion.
9216      if (NumArgs > 0 && PartialOverloading)
9217        return NumArgs + 1 > NumParams; // If so, we view as an extra argument.
9218      return NumArgs > NumParams;
9219    }
9220  
9221    // Emitting members of dllexported classes is delayed until the class
9222    // (including field initializers) is fully parsed.
9223    SmallVector<CXXRecordDecl*, 4> DelayedDllExportClasses;
9224  };
9225  
9226  /// \brief RAII object that enters a new expression evaluation context.
9227  class EnterExpressionEvaluationContext {
9228    Sema &Actions;
9229  
9230  public:
9231    EnterExpressionEvaluationContext(Sema &Actions,
9232                                     Sema::ExpressionEvaluationContext NewContext,
9233                                     Decl *LambdaContextDecl = nullptr,
9234                                     bool IsDecltype = false)
Actions(Actions)9235      : Actions(Actions) {
9236      Actions.PushExpressionEvaluationContext(NewContext, LambdaContextDecl,
9237                                              IsDecltype);
9238    }
9239    EnterExpressionEvaluationContext(Sema &Actions,
9240                                     Sema::ExpressionEvaluationContext NewContext,
9241                                     Sema::ReuseLambdaContextDecl_t,
9242                                     bool IsDecltype = false)
Actions(Actions)9243      : Actions(Actions) {
9244      Actions.PushExpressionEvaluationContext(NewContext,
9245                                              Sema::ReuseLambdaContextDecl,
9246                                              IsDecltype);
9247    }
9248  
~EnterExpressionEvaluationContext()9249    ~EnterExpressionEvaluationContext() {
9250      Actions.PopExpressionEvaluationContext();
9251    }
9252  };
9253  
9254  DeductionFailureInfo
9255  MakeDeductionFailureInfo(ASTContext &Context, Sema::TemplateDeductionResult TDK,
9256                           sema::TemplateDeductionInfo &Info);
9257  
9258  /// \brief Contains a late templated function.
9259  /// Will be parsed at the end of the translation unit, used by Sema & Parser.
9260  struct LateParsedTemplate {
9261    CachedTokens Toks;
9262    /// \brief The template function declaration to be late parsed.
9263    Decl *D;
9264  };
9265  
9266  } // end namespace clang
9267  
9268  #endif
9269