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1 //===--- Parser.cpp - C Language Family Parser ----------------------------===//
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 implements the Parser interfaces.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/Parse/Parser.h"
15 #include "RAIIObjectsForParser.h"
16 #include "clang/AST/ASTConsumer.h"
17 #include "clang/AST/ASTContext.h"
18 #include "clang/AST/DeclTemplate.h"
19 #include "clang/Parse/ParseDiagnostic.h"
20 #include "clang/Sema/DeclSpec.h"
21 #include "clang/Sema/ParsedTemplate.h"
22 #include "clang/Sema/Scope.h"
23 #include "llvm/Support/raw_ostream.h"
24 using namespace clang;
25 
26 
27 namespace {
28 /// \brief A comment handler that passes comments found by the preprocessor
29 /// to the parser action.
30 class ActionCommentHandler : public CommentHandler {
31   Sema &S;
32 
33 public:
ActionCommentHandler(Sema & S)34   explicit ActionCommentHandler(Sema &S) : S(S) { }
35 
HandleComment(Preprocessor & PP,SourceRange Comment)36   bool HandleComment(Preprocessor &PP, SourceRange Comment) override {
37     S.ActOnComment(Comment);
38     return false;
39   }
40 };
41 
42 /// \brief RAIIObject to destroy the contents of a SmallVector of
43 /// TemplateIdAnnotation pointers and clear the vector.
44 class DestroyTemplateIdAnnotationsRAIIObj {
45   SmallVectorImpl<TemplateIdAnnotation *> &Container;
46 
47 public:
DestroyTemplateIdAnnotationsRAIIObj(SmallVectorImpl<TemplateIdAnnotation * > & Container)48   DestroyTemplateIdAnnotationsRAIIObj(
49       SmallVectorImpl<TemplateIdAnnotation *> &Container)
50       : Container(Container) {}
51 
~DestroyTemplateIdAnnotationsRAIIObj()52   ~DestroyTemplateIdAnnotationsRAIIObj() {
53     for (SmallVectorImpl<TemplateIdAnnotation *>::iterator I =
54              Container.begin(),
55                                                            E = Container.end();
56          I != E; ++I)
57       (*I)->Destroy();
58     Container.clear();
59   }
60 };
61 } // end anonymous namespace
62 
getSEHExceptKeyword()63 IdentifierInfo *Parser::getSEHExceptKeyword() {
64   // __except is accepted as a (contextual) keyword
65   if (!Ident__except && (getLangOpts().MicrosoftExt || getLangOpts().Borland))
66     Ident__except = PP.getIdentifierInfo("__except");
67 
68   return Ident__except;
69 }
70 
Parser(Preprocessor & pp,Sema & actions,bool skipFunctionBodies)71 Parser::Parser(Preprocessor &pp, Sema &actions, bool skipFunctionBodies)
72   : PP(pp), Actions(actions), Diags(PP.getDiagnostics()),
73     GreaterThanIsOperator(true), ColonIsSacred(false),
74     InMessageExpression(false), TemplateParameterDepth(0),
75     ParsingInObjCContainer(false) {
76   SkipFunctionBodies = pp.isCodeCompletionEnabled() || skipFunctionBodies;
77   Tok.startToken();
78   Tok.setKind(tok::eof);
79   Actions.CurScope = nullptr;
80   NumCachedScopes = 0;
81   ParenCount = BracketCount = BraceCount = 0;
82   CurParsedObjCImpl = nullptr;
83 
84   // Add #pragma handlers. These are removed and destroyed in the
85   // destructor.
86   initializePragmaHandlers();
87 
88   CommentSemaHandler.reset(new ActionCommentHandler(actions));
89   PP.addCommentHandler(CommentSemaHandler.get());
90 
91   PP.setCodeCompletionHandler(*this);
92 }
93 
Diag(SourceLocation Loc,unsigned DiagID)94 DiagnosticBuilder Parser::Diag(SourceLocation Loc, unsigned DiagID) {
95   return Diags.Report(Loc, DiagID);
96 }
97 
Diag(const Token & Tok,unsigned DiagID)98 DiagnosticBuilder Parser::Diag(const Token &Tok, unsigned DiagID) {
99   return Diag(Tok.getLocation(), DiagID);
100 }
101 
102 /// \brief Emits a diagnostic suggesting parentheses surrounding a
103 /// given range.
104 ///
105 /// \param Loc The location where we'll emit the diagnostic.
106 /// \param DK The kind of diagnostic to emit.
107 /// \param ParenRange Source range enclosing code that should be parenthesized.
SuggestParentheses(SourceLocation Loc,unsigned DK,SourceRange ParenRange)108 void Parser::SuggestParentheses(SourceLocation Loc, unsigned DK,
109                                 SourceRange ParenRange) {
110   SourceLocation EndLoc = PP.getLocForEndOfToken(ParenRange.getEnd());
111   if (!ParenRange.getEnd().isFileID() || EndLoc.isInvalid()) {
112     // We can't display the parentheses, so just dig the
113     // warning/error and return.
114     Diag(Loc, DK);
115     return;
116   }
117 
118   Diag(Loc, DK)
119     << FixItHint::CreateInsertion(ParenRange.getBegin(), "(")
120     << FixItHint::CreateInsertion(EndLoc, ")");
121 }
122 
IsCommonTypo(tok::TokenKind ExpectedTok,const Token & Tok)123 static bool IsCommonTypo(tok::TokenKind ExpectedTok, const Token &Tok) {
124   switch (ExpectedTok) {
125   case tok::semi:
126     return Tok.is(tok::colon) || Tok.is(tok::comma); // : or , for ;
127   default: return false;
128   }
129 }
130 
ExpectAndConsume(tok::TokenKind ExpectedTok,unsigned DiagID,StringRef Msg)131 bool Parser::ExpectAndConsume(tok::TokenKind ExpectedTok, unsigned DiagID,
132                               StringRef Msg) {
133   if (Tok.is(ExpectedTok) || Tok.is(tok::code_completion)) {
134     ConsumeAnyToken();
135     return false;
136   }
137 
138   // Detect common single-character typos and resume.
139   if (IsCommonTypo(ExpectedTok, Tok)) {
140     SourceLocation Loc = Tok.getLocation();
141     {
142       DiagnosticBuilder DB = Diag(Loc, DiagID);
143       DB << FixItHint::CreateReplacement(
144                 SourceRange(Loc), tok::getPunctuatorSpelling(ExpectedTok));
145       if (DiagID == diag::err_expected)
146         DB << ExpectedTok;
147       else if (DiagID == diag::err_expected_after)
148         DB << Msg << ExpectedTok;
149       else
150         DB << Msg;
151     }
152 
153     // Pretend there wasn't a problem.
154     ConsumeAnyToken();
155     return false;
156   }
157 
158   SourceLocation EndLoc = PP.getLocForEndOfToken(PrevTokLocation);
159   const char *Spelling = nullptr;
160   if (EndLoc.isValid())
161     Spelling = tok::getPunctuatorSpelling(ExpectedTok);
162 
163   DiagnosticBuilder DB =
164       Spelling
165           ? Diag(EndLoc, DiagID) << FixItHint::CreateInsertion(EndLoc, Spelling)
166           : Diag(Tok, DiagID);
167   if (DiagID == diag::err_expected)
168     DB << ExpectedTok;
169   else if (DiagID == diag::err_expected_after)
170     DB << Msg << ExpectedTok;
171   else
172     DB << Msg;
173 
174   return true;
175 }
176 
ExpectAndConsumeSemi(unsigned DiagID)177 bool Parser::ExpectAndConsumeSemi(unsigned DiagID) {
178   if (TryConsumeToken(tok::semi))
179     return false;
180 
181   if (Tok.is(tok::code_completion)) {
182     handleUnexpectedCodeCompletionToken();
183     return false;
184   }
185 
186   if ((Tok.is(tok::r_paren) || Tok.is(tok::r_square)) &&
187       NextToken().is(tok::semi)) {
188     Diag(Tok, diag::err_extraneous_token_before_semi)
189       << PP.getSpelling(Tok)
190       << FixItHint::CreateRemoval(Tok.getLocation());
191     ConsumeAnyToken(); // The ')' or ']'.
192     ConsumeToken(); // The ';'.
193     return false;
194   }
195 
196   return ExpectAndConsume(tok::semi, DiagID);
197 }
198 
ConsumeExtraSemi(ExtraSemiKind Kind,unsigned TST)199 void Parser::ConsumeExtraSemi(ExtraSemiKind Kind, unsigned TST) {
200   if (!Tok.is(tok::semi)) return;
201 
202   bool HadMultipleSemis = false;
203   SourceLocation StartLoc = Tok.getLocation();
204   SourceLocation EndLoc = Tok.getLocation();
205   ConsumeToken();
206 
207   while ((Tok.is(tok::semi) && !Tok.isAtStartOfLine())) {
208     HadMultipleSemis = true;
209     EndLoc = Tok.getLocation();
210     ConsumeToken();
211   }
212 
213   // C++11 allows extra semicolons at namespace scope, but not in any of the
214   // other contexts.
215   if (Kind == OutsideFunction && getLangOpts().CPlusPlus) {
216     if (getLangOpts().CPlusPlus11)
217       Diag(StartLoc, diag::warn_cxx98_compat_top_level_semi)
218           << FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
219     else
220       Diag(StartLoc, diag::ext_extra_semi_cxx11)
221           << FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
222     return;
223   }
224 
225   if (Kind != AfterMemberFunctionDefinition || HadMultipleSemis)
226     Diag(StartLoc, diag::ext_extra_semi)
227         << Kind << DeclSpec::getSpecifierName((DeclSpec::TST)TST,
228                                     Actions.getASTContext().getPrintingPolicy())
229         << FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
230   else
231     // A single semicolon is valid after a member function definition.
232     Diag(StartLoc, diag::warn_extra_semi_after_mem_fn_def)
233       << FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
234 }
235 
236 //===----------------------------------------------------------------------===//
237 // Error recovery.
238 //===----------------------------------------------------------------------===//
239 
HasFlagsSet(Parser::SkipUntilFlags L,Parser::SkipUntilFlags R)240 static bool HasFlagsSet(Parser::SkipUntilFlags L, Parser::SkipUntilFlags R) {
241   return (static_cast<unsigned>(L) & static_cast<unsigned>(R)) != 0;
242 }
243 
244 /// SkipUntil - Read tokens until we get to the specified token, then consume
245 /// it (unless no flag StopBeforeMatch).  Because we cannot guarantee that the
246 /// token will ever occur, this skips to the next token, or to some likely
247 /// good stopping point.  If StopAtSemi is true, skipping will stop at a ';'
248 /// character.
249 ///
250 /// If SkipUntil finds the specified token, it returns true, otherwise it
251 /// returns false.
SkipUntil(ArrayRef<tok::TokenKind> Toks,SkipUntilFlags Flags)252 bool Parser::SkipUntil(ArrayRef<tok::TokenKind> Toks, SkipUntilFlags Flags) {
253   // We always want this function to skip at least one token if the first token
254   // isn't T and if not at EOF.
255   bool isFirstTokenSkipped = true;
256   while (1) {
257     // If we found one of the tokens, stop and return true.
258     for (unsigned i = 0, NumToks = Toks.size(); i != NumToks; ++i) {
259       if (Tok.is(Toks[i])) {
260         if (HasFlagsSet(Flags, StopBeforeMatch)) {
261           // Noop, don't consume the token.
262         } else {
263           ConsumeAnyToken();
264         }
265         return true;
266       }
267     }
268 
269     // Important special case: The caller has given up and just wants us to
270     // skip the rest of the file. Do this without recursing, since we can
271     // get here precisely because the caller detected too much recursion.
272     if (Toks.size() == 1 && Toks[0] == tok::eof &&
273         !HasFlagsSet(Flags, StopAtSemi) &&
274         !HasFlagsSet(Flags, StopAtCodeCompletion)) {
275       while (Tok.isNot(tok::eof))
276         ConsumeAnyToken();
277       return true;
278     }
279 
280     switch (Tok.getKind()) {
281     case tok::eof:
282       // Ran out of tokens.
283       return false;
284 
285     case tok::annot_pragma_openmp:
286     case tok::annot_pragma_openmp_end:
287       // Stop before an OpenMP pragma boundary.
288     case tok::annot_module_begin:
289     case tok::annot_module_end:
290     case tok::annot_module_include:
291       // Stop before we change submodules. They generally indicate a "good"
292       // place to pick up parsing again (except in the special case where
293       // we're trying to skip to EOF).
294       return false;
295 
296     case tok::code_completion:
297       if (!HasFlagsSet(Flags, StopAtCodeCompletion))
298         handleUnexpectedCodeCompletionToken();
299       return false;
300 
301     case tok::l_paren:
302       // Recursively skip properly-nested parens.
303       ConsumeParen();
304       if (HasFlagsSet(Flags, StopAtCodeCompletion))
305         SkipUntil(tok::r_paren, StopAtCodeCompletion);
306       else
307         SkipUntil(tok::r_paren);
308       break;
309     case tok::l_square:
310       // Recursively skip properly-nested square brackets.
311       ConsumeBracket();
312       if (HasFlagsSet(Flags, StopAtCodeCompletion))
313         SkipUntil(tok::r_square, StopAtCodeCompletion);
314       else
315         SkipUntil(tok::r_square);
316       break;
317     case tok::l_brace:
318       // Recursively skip properly-nested braces.
319       ConsumeBrace();
320       if (HasFlagsSet(Flags, StopAtCodeCompletion))
321         SkipUntil(tok::r_brace, StopAtCodeCompletion);
322       else
323         SkipUntil(tok::r_brace);
324       break;
325 
326     // Okay, we found a ']' or '}' or ')', which we think should be balanced.
327     // Since the user wasn't looking for this token (if they were, it would
328     // already be handled), this isn't balanced.  If there is a LHS token at a
329     // higher level, we will assume that this matches the unbalanced token
330     // and return it.  Otherwise, this is a spurious RHS token, which we skip.
331     case tok::r_paren:
332       if (ParenCount && !isFirstTokenSkipped)
333         return false;  // Matches something.
334       ConsumeParen();
335       break;
336     case tok::r_square:
337       if (BracketCount && !isFirstTokenSkipped)
338         return false;  // Matches something.
339       ConsumeBracket();
340       break;
341     case tok::r_brace:
342       if (BraceCount && !isFirstTokenSkipped)
343         return false;  // Matches something.
344       ConsumeBrace();
345       break;
346 
347     case tok::string_literal:
348     case tok::wide_string_literal:
349     case tok::utf8_string_literal:
350     case tok::utf16_string_literal:
351     case tok::utf32_string_literal:
352       ConsumeStringToken();
353       break;
354 
355     case tok::semi:
356       if (HasFlagsSet(Flags, StopAtSemi))
357         return false;
358       // FALL THROUGH.
359     default:
360       // Skip this token.
361       ConsumeToken();
362       break;
363     }
364     isFirstTokenSkipped = false;
365   }
366 }
367 
368 //===----------------------------------------------------------------------===//
369 // Scope manipulation
370 //===----------------------------------------------------------------------===//
371 
372 /// EnterScope - Start a new scope.
EnterScope(unsigned ScopeFlags)373 void Parser::EnterScope(unsigned ScopeFlags) {
374   if (NumCachedScopes) {
375     Scope *N = ScopeCache[--NumCachedScopes];
376     N->Init(getCurScope(), ScopeFlags);
377     Actions.CurScope = N;
378   } else {
379     Actions.CurScope = new Scope(getCurScope(), ScopeFlags, Diags);
380   }
381 }
382 
383 /// ExitScope - Pop a scope off the scope stack.
ExitScope()384 void Parser::ExitScope() {
385   assert(getCurScope() && "Scope imbalance!");
386 
387   // Inform the actions module that this scope is going away if there are any
388   // decls in it.
389   Actions.ActOnPopScope(Tok.getLocation(), getCurScope());
390 
391   Scope *OldScope = getCurScope();
392   Actions.CurScope = OldScope->getParent();
393 
394   if (NumCachedScopes == ScopeCacheSize)
395     delete OldScope;
396   else
397     ScopeCache[NumCachedScopes++] = OldScope;
398 }
399 
400 /// Set the flags for the current scope to ScopeFlags. If ManageFlags is false,
401 /// this object does nothing.
ParseScopeFlags(Parser * Self,unsigned ScopeFlags,bool ManageFlags)402 Parser::ParseScopeFlags::ParseScopeFlags(Parser *Self, unsigned ScopeFlags,
403                                  bool ManageFlags)
404   : CurScope(ManageFlags ? Self->getCurScope() : nullptr) {
405   if (CurScope) {
406     OldFlags = CurScope->getFlags();
407     CurScope->setFlags(ScopeFlags);
408   }
409 }
410 
411 /// Restore the flags for the current scope to what they were before this
412 /// object overrode them.
~ParseScopeFlags()413 Parser::ParseScopeFlags::~ParseScopeFlags() {
414   if (CurScope)
415     CurScope->setFlags(OldFlags);
416 }
417 
418 
419 //===----------------------------------------------------------------------===//
420 // C99 6.9: External Definitions.
421 //===----------------------------------------------------------------------===//
422 
~Parser()423 Parser::~Parser() {
424   // If we still have scopes active, delete the scope tree.
425   delete getCurScope();
426   Actions.CurScope = nullptr;
427 
428   // Free the scope cache.
429   for (unsigned i = 0, e = NumCachedScopes; i != e; ++i)
430     delete ScopeCache[i];
431 
432   resetPragmaHandlers();
433 
434   PP.removeCommentHandler(CommentSemaHandler.get());
435 
436   PP.clearCodeCompletionHandler();
437 
438   if (getLangOpts().DelayedTemplateParsing &&
439       !PP.isIncrementalProcessingEnabled() && !TemplateIds.empty()) {
440     // If an ASTConsumer parsed delay-parsed templates in their
441     // HandleTranslationUnit() method, TemplateIds created there were not
442     // guarded by a DestroyTemplateIdAnnotationsRAIIObj object in
443     // ParseTopLevelDecl(). Destroy them here.
444     DestroyTemplateIdAnnotationsRAIIObj CleanupRAII(TemplateIds);
445   }
446 
447   assert(TemplateIds.empty() && "Still alive TemplateIdAnnotations around?");
448 }
449 
450 /// Initialize - Warm up the parser.
451 ///
Initialize()452 void Parser::Initialize() {
453   // Create the translation unit scope.  Install it as the current scope.
454   assert(getCurScope() == nullptr && "A scope is already active?");
455   EnterScope(Scope::DeclScope);
456   Actions.ActOnTranslationUnitScope(getCurScope());
457 
458   // Initialization for Objective-C context sensitive keywords recognition.
459   // Referenced in Parser::ParseObjCTypeQualifierList.
460   if (getLangOpts().ObjC1) {
461     ObjCTypeQuals[objc_in] = &PP.getIdentifierTable().get("in");
462     ObjCTypeQuals[objc_out] = &PP.getIdentifierTable().get("out");
463     ObjCTypeQuals[objc_inout] = &PP.getIdentifierTable().get("inout");
464     ObjCTypeQuals[objc_oneway] = &PP.getIdentifierTable().get("oneway");
465     ObjCTypeQuals[objc_bycopy] = &PP.getIdentifierTable().get("bycopy");
466     ObjCTypeQuals[objc_byref] = &PP.getIdentifierTable().get("byref");
467     ObjCTypeQuals[objc_nonnull] = &PP.getIdentifierTable().get("nonnull");
468     ObjCTypeQuals[objc_nullable] = &PP.getIdentifierTable().get("nullable");
469     ObjCTypeQuals[objc_null_unspecified]
470       = &PP.getIdentifierTable().get("null_unspecified");
471   }
472 
473   Ident_instancetype = nullptr;
474   Ident_final = nullptr;
475   Ident_sealed = nullptr;
476   Ident_override = nullptr;
477 
478   Ident_super = &PP.getIdentifierTable().get("super");
479 
480   Ident_vector = nullptr;
481   Ident_bool = nullptr;
482   Ident_pixel = nullptr;
483   if (getLangOpts().AltiVec || getLangOpts().ZVector) {
484     Ident_vector = &PP.getIdentifierTable().get("vector");
485     Ident_bool = &PP.getIdentifierTable().get("bool");
486   }
487   if (getLangOpts().AltiVec)
488     Ident_pixel = &PP.getIdentifierTable().get("pixel");
489 
490   Ident_introduced = nullptr;
491   Ident_deprecated = nullptr;
492   Ident_obsoleted = nullptr;
493   Ident_unavailable = nullptr;
494   Ident_strict = nullptr;
495   Ident_replacement = nullptr;
496 
497   Ident__except = nullptr;
498 
499   Ident__exception_code = Ident__exception_info = nullptr;
500   Ident__abnormal_termination = Ident___exception_code = nullptr;
501   Ident___exception_info = Ident___abnormal_termination = nullptr;
502   Ident_GetExceptionCode = Ident_GetExceptionInfo = nullptr;
503   Ident_AbnormalTermination = nullptr;
504 
505   if(getLangOpts().Borland) {
506     Ident__exception_info        = PP.getIdentifierInfo("_exception_info");
507     Ident___exception_info       = PP.getIdentifierInfo("__exception_info");
508     Ident_GetExceptionInfo       = PP.getIdentifierInfo("GetExceptionInformation");
509     Ident__exception_code        = PP.getIdentifierInfo("_exception_code");
510     Ident___exception_code       = PP.getIdentifierInfo("__exception_code");
511     Ident_GetExceptionCode       = PP.getIdentifierInfo("GetExceptionCode");
512     Ident__abnormal_termination  = PP.getIdentifierInfo("_abnormal_termination");
513     Ident___abnormal_termination = PP.getIdentifierInfo("__abnormal_termination");
514     Ident_AbnormalTermination    = PP.getIdentifierInfo("AbnormalTermination");
515 
516     PP.SetPoisonReason(Ident__exception_code,diag::err_seh___except_block);
517     PP.SetPoisonReason(Ident___exception_code,diag::err_seh___except_block);
518     PP.SetPoisonReason(Ident_GetExceptionCode,diag::err_seh___except_block);
519     PP.SetPoisonReason(Ident__exception_info,diag::err_seh___except_filter);
520     PP.SetPoisonReason(Ident___exception_info,diag::err_seh___except_filter);
521     PP.SetPoisonReason(Ident_GetExceptionInfo,diag::err_seh___except_filter);
522     PP.SetPoisonReason(Ident__abnormal_termination,diag::err_seh___finally_block);
523     PP.SetPoisonReason(Ident___abnormal_termination,diag::err_seh___finally_block);
524     PP.SetPoisonReason(Ident_AbnormalTermination,diag::err_seh___finally_block);
525   }
526 
527   Actions.Initialize();
528 
529   // Prime the lexer look-ahead.
530   ConsumeToken();
531 }
532 
LateTemplateParserCleanupCallback(void * P)533 void Parser::LateTemplateParserCleanupCallback(void *P) {
534   // While this RAII helper doesn't bracket any actual work, the destructor will
535   // clean up annotations that were created during ActOnEndOfTranslationUnit
536   // when incremental processing is enabled.
537   DestroyTemplateIdAnnotationsRAIIObj CleanupRAII(((Parser *)P)->TemplateIds);
538 }
539 
540 /// ParseTopLevelDecl - Parse one top-level declaration, return whatever the
541 /// action tells us to.  This returns true if the EOF was encountered.
ParseTopLevelDecl(DeclGroupPtrTy & Result)542 bool Parser::ParseTopLevelDecl(DeclGroupPtrTy &Result) {
543   DestroyTemplateIdAnnotationsRAIIObj CleanupRAII(TemplateIds);
544 
545   // Skip over the EOF token, flagging end of previous input for incremental
546   // processing
547   if (PP.isIncrementalProcessingEnabled() && Tok.is(tok::eof))
548     ConsumeToken();
549 
550   Result = nullptr;
551   switch (Tok.getKind()) {
552   case tok::annot_pragma_unused:
553     HandlePragmaUnused();
554     return false;
555 
556   case tok::annot_module_include:
557     Actions.ActOnModuleInclude(Tok.getLocation(),
558                                reinterpret_cast<Module *>(
559                                    Tok.getAnnotationValue()));
560     ConsumeToken();
561     return false;
562 
563   case tok::annot_module_begin:
564     Actions.ActOnModuleBegin(Tok.getLocation(), reinterpret_cast<Module *>(
565                                                     Tok.getAnnotationValue()));
566     ConsumeToken();
567     return false;
568 
569   case tok::annot_module_end:
570     Actions.ActOnModuleEnd(Tok.getLocation(), reinterpret_cast<Module *>(
571                                                   Tok.getAnnotationValue()));
572     ConsumeToken();
573     return false;
574 
575   case tok::eof:
576     // Late template parsing can begin.
577     if (getLangOpts().DelayedTemplateParsing)
578       Actions.SetLateTemplateParser(LateTemplateParserCallback,
579                                     PP.isIncrementalProcessingEnabled() ?
580                                     LateTemplateParserCleanupCallback : nullptr,
581                                     this);
582     if (!PP.isIncrementalProcessingEnabled())
583       Actions.ActOnEndOfTranslationUnit();
584     //else don't tell Sema that we ended parsing: more input might come.
585     return true;
586 
587   default:
588     break;
589   }
590 
591   ParsedAttributesWithRange attrs(AttrFactory);
592   MaybeParseCXX11Attributes(attrs);
593   MaybeParseMicrosoftAttributes(attrs);
594 
595   Result = ParseExternalDeclaration(attrs);
596   return false;
597 }
598 
599 /// ParseExternalDeclaration:
600 ///
601 ///       external-declaration: [C99 6.9], declaration: [C++ dcl.dcl]
602 ///         function-definition
603 ///         declaration
604 /// [GNU]   asm-definition
605 /// [GNU]   __extension__ external-declaration
606 /// [OBJC]  objc-class-definition
607 /// [OBJC]  objc-class-declaration
608 /// [OBJC]  objc-alias-declaration
609 /// [OBJC]  objc-protocol-definition
610 /// [OBJC]  objc-method-definition
611 /// [OBJC]  @end
612 /// [C++]   linkage-specification
613 /// [GNU] asm-definition:
614 ///         simple-asm-expr ';'
615 /// [C++11] empty-declaration
616 /// [C++11] attribute-declaration
617 ///
618 /// [C++11] empty-declaration:
619 ///           ';'
620 ///
621 /// [C++0x/GNU] 'extern' 'template' declaration
622 Parser::DeclGroupPtrTy
ParseExternalDeclaration(ParsedAttributesWithRange & attrs,ParsingDeclSpec * DS)623 Parser::ParseExternalDeclaration(ParsedAttributesWithRange &attrs,
624                                  ParsingDeclSpec *DS) {
625   DestroyTemplateIdAnnotationsRAIIObj CleanupRAII(TemplateIds);
626   ParenBraceBracketBalancer BalancerRAIIObj(*this);
627 
628   if (PP.isCodeCompletionReached()) {
629     cutOffParsing();
630     return nullptr;
631   }
632 
633   Decl *SingleDecl = nullptr;
634   switch (Tok.getKind()) {
635   case tok::annot_pragma_vis:
636     HandlePragmaVisibility();
637     return nullptr;
638   case tok::annot_pragma_pack:
639     HandlePragmaPack();
640     return nullptr;
641   case tok::annot_pragma_msstruct:
642     HandlePragmaMSStruct();
643     return nullptr;
644   case tok::annot_pragma_align:
645     HandlePragmaAlign();
646     return nullptr;
647   case tok::annot_pragma_weak:
648     HandlePragmaWeak();
649     return nullptr;
650   case tok::annot_pragma_weakalias:
651     HandlePragmaWeakAlias();
652     return nullptr;
653   case tok::annot_pragma_redefine_extname:
654     HandlePragmaRedefineExtname();
655     return nullptr;
656   case tok::annot_pragma_fp_contract:
657     HandlePragmaFPContract();
658     return nullptr;
659   case tok::annot_pragma_opencl_extension:
660     HandlePragmaOpenCLExtension();
661     return nullptr;
662   case tok::annot_pragma_openmp: {
663     AccessSpecifier AS = AS_none;
664     return ParseOpenMPDeclarativeDirectiveWithExtDecl(AS, attrs);
665   }
666   case tok::annot_pragma_ms_pointers_to_members:
667     HandlePragmaMSPointersToMembers();
668     return nullptr;
669   case tok::annot_pragma_ms_vtordisp:
670     HandlePragmaMSVtorDisp();
671     return nullptr;
672   case tok::annot_pragma_ms_pragma:
673     HandlePragmaMSPragma();
674     return nullptr;
675   case tok::annot_pragma_dump:
676     HandlePragmaDump();
677     return nullptr;
678   case tok::semi:
679     // Either a C++11 empty-declaration or attribute-declaration.
680     SingleDecl = Actions.ActOnEmptyDeclaration(getCurScope(),
681                                                attrs.getList(),
682                                                Tok.getLocation());
683     ConsumeExtraSemi(OutsideFunction);
684     break;
685   case tok::r_brace:
686     Diag(Tok, diag::err_extraneous_closing_brace);
687     ConsumeBrace();
688     return nullptr;
689   case tok::eof:
690     Diag(Tok, diag::err_expected_external_declaration);
691     return nullptr;
692   case tok::kw___extension__: {
693     // __extension__ silences extension warnings in the subexpression.
694     ExtensionRAIIObject O(Diags);  // Use RAII to do this.
695     ConsumeToken();
696     return ParseExternalDeclaration(attrs);
697   }
698   case tok::kw_asm: {
699     ProhibitAttributes(attrs);
700 
701     SourceLocation StartLoc = Tok.getLocation();
702     SourceLocation EndLoc;
703 
704     ExprResult Result(ParseSimpleAsm(&EndLoc));
705 
706     // Check if GNU-style InlineAsm is disabled.
707     // Empty asm string is allowed because it will not introduce
708     // any assembly code.
709     if (!(getLangOpts().GNUAsm || Result.isInvalid())) {
710       const auto *SL = cast<StringLiteral>(Result.get());
711       if (!SL->getString().trim().empty())
712         Diag(StartLoc, diag::err_gnu_inline_asm_disabled);
713     }
714 
715     ExpectAndConsume(tok::semi, diag::err_expected_after,
716                      "top-level asm block");
717 
718     if (Result.isInvalid())
719       return nullptr;
720     SingleDecl = Actions.ActOnFileScopeAsmDecl(Result.get(), StartLoc, EndLoc);
721     break;
722   }
723   case tok::at:
724     return ParseObjCAtDirectives();
725   case tok::minus:
726   case tok::plus:
727     if (!getLangOpts().ObjC1) {
728       Diag(Tok, diag::err_expected_external_declaration);
729       ConsumeToken();
730       return nullptr;
731     }
732     SingleDecl = ParseObjCMethodDefinition();
733     break;
734   case tok::code_completion:
735       Actions.CodeCompleteOrdinaryName(getCurScope(),
736                              CurParsedObjCImpl? Sema::PCC_ObjCImplementation
737                                               : Sema::PCC_Namespace);
738     cutOffParsing();
739     return nullptr;
740   case tok::kw_using:
741   case tok::kw_namespace:
742   case tok::kw_typedef:
743   case tok::kw_template:
744   case tok::kw_export:    // As in 'export template'
745   case tok::kw_static_assert:
746   case tok::kw__Static_assert:
747     // A function definition cannot start with any of these keywords.
748     {
749       SourceLocation DeclEnd;
750       return ParseDeclaration(Declarator::FileContext, DeclEnd, attrs);
751     }
752 
753   case tok::kw_static:
754     // Parse (then ignore) 'static' prior to a template instantiation. This is
755     // a GCC extension that we intentionally do not support.
756     if (getLangOpts().CPlusPlus && NextToken().is(tok::kw_template)) {
757       Diag(ConsumeToken(), diag::warn_static_inline_explicit_inst_ignored)
758         << 0;
759       SourceLocation DeclEnd;
760       return ParseDeclaration(Declarator::FileContext, DeclEnd, attrs);
761     }
762     goto dont_know;
763 
764   case tok::kw_inline:
765     if (getLangOpts().CPlusPlus) {
766       tok::TokenKind NextKind = NextToken().getKind();
767 
768       // Inline namespaces. Allowed as an extension even in C++03.
769       if (NextKind == tok::kw_namespace) {
770         SourceLocation DeclEnd;
771         return ParseDeclaration(Declarator::FileContext, DeclEnd, attrs);
772       }
773 
774       // Parse (then ignore) 'inline' prior to a template instantiation. This is
775       // a GCC extension that we intentionally do not support.
776       if (NextKind == tok::kw_template) {
777         Diag(ConsumeToken(), diag::warn_static_inline_explicit_inst_ignored)
778           << 1;
779         SourceLocation DeclEnd;
780         return ParseDeclaration(Declarator::FileContext, DeclEnd, attrs);
781       }
782     }
783     goto dont_know;
784 
785   case tok::kw_extern:
786     if (getLangOpts().CPlusPlus && NextToken().is(tok::kw_template)) {
787       // Extern templates
788       SourceLocation ExternLoc = ConsumeToken();
789       SourceLocation TemplateLoc = ConsumeToken();
790       Diag(ExternLoc, getLangOpts().CPlusPlus11 ?
791              diag::warn_cxx98_compat_extern_template :
792              diag::ext_extern_template) << SourceRange(ExternLoc, TemplateLoc);
793       SourceLocation DeclEnd;
794       return Actions.ConvertDeclToDeclGroup(
795                   ParseExplicitInstantiation(Declarator::FileContext,
796                                              ExternLoc, TemplateLoc, DeclEnd));
797     }
798     goto dont_know;
799 
800   case tok::kw___if_exists:
801   case tok::kw___if_not_exists:
802     ParseMicrosoftIfExistsExternalDeclaration();
803     return nullptr;
804 
805   default:
806   dont_know:
807     // We can't tell whether this is a function-definition or declaration yet.
808     return ParseDeclarationOrFunctionDefinition(attrs, DS);
809   }
810 
811   // This routine returns a DeclGroup, if the thing we parsed only contains a
812   // single decl, convert it now.
813   return Actions.ConvertDeclToDeclGroup(SingleDecl);
814 }
815 
816 /// \brief Determine whether the current token, if it occurs after a
817 /// declarator, continues a declaration or declaration list.
isDeclarationAfterDeclarator()818 bool Parser::isDeclarationAfterDeclarator() {
819   // Check for '= delete' or '= default'
820   if (getLangOpts().CPlusPlus && Tok.is(tok::equal)) {
821     const Token &KW = NextToken();
822     if (KW.is(tok::kw_default) || KW.is(tok::kw_delete))
823       return false;
824   }
825 
826   return Tok.is(tok::equal) ||      // int X()=  -> not a function def
827     Tok.is(tok::comma) ||           // int X(),  -> not a function def
828     Tok.is(tok::semi)  ||           // int X();  -> not a function def
829     Tok.is(tok::kw_asm) ||          // int X() __asm__ -> not a function def
830     Tok.is(tok::kw___attribute) ||  // int X() __attr__ -> not a function def
831     (getLangOpts().CPlusPlus &&
832      Tok.is(tok::l_paren));         // int X(0) -> not a function def [C++]
833 }
834 
835 /// \brief Determine whether the current token, if it occurs after a
836 /// declarator, indicates the start of a function definition.
isStartOfFunctionDefinition(const ParsingDeclarator & Declarator)837 bool Parser::isStartOfFunctionDefinition(const ParsingDeclarator &Declarator) {
838   assert(Declarator.isFunctionDeclarator() && "Isn't a function declarator");
839   if (Tok.is(tok::l_brace))   // int X() {}
840     return true;
841 
842   // Handle K&R C argument lists: int X(f) int f; {}
843   if (!getLangOpts().CPlusPlus &&
844       Declarator.getFunctionTypeInfo().isKNRPrototype())
845     return isDeclarationSpecifier();
846 
847   if (getLangOpts().CPlusPlus && Tok.is(tok::equal)) {
848     const Token &KW = NextToken();
849     return KW.is(tok::kw_default) || KW.is(tok::kw_delete);
850   }
851 
852   return Tok.is(tok::colon) ||         // X() : Base() {} (used for ctors)
853          Tok.is(tok::kw_try);          // X() try { ... }
854 }
855 
856 /// ParseDeclarationOrFunctionDefinition - Parse either a function-definition or
857 /// a declaration.  We can't tell which we have until we read up to the
858 /// compound-statement in function-definition. TemplateParams, if
859 /// non-NULL, provides the template parameters when we're parsing a
860 /// C++ template-declaration.
861 ///
862 ///       function-definition: [C99 6.9.1]
863 ///         decl-specs      declarator declaration-list[opt] compound-statement
864 /// [C90] function-definition: [C99 6.7.1] - implicit int result
865 /// [C90]   decl-specs[opt] declarator declaration-list[opt] compound-statement
866 ///
867 ///       declaration: [C99 6.7]
868 ///         declaration-specifiers init-declarator-list[opt] ';'
869 /// [!C99]  init-declarator-list ';'                   [TODO: warn in c99 mode]
870 /// [OMP]   threadprivate-directive                              [TODO]
871 ///
872 Parser::DeclGroupPtrTy
ParseDeclOrFunctionDefInternal(ParsedAttributesWithRange & attrs,ParsingDeclSpec & DS,AccessSpecifier AS)873 Parser::ParseDeclOrFunctionDefInternal(ParsedAttributesWithRange &attrs,
874                                        ParsingDeclSpec &DS,
875                                        AccessSpecifier AS) {
876   // Parse the common declaration-specifiers piece.
877   ParseDeclarationSpecifiers(DS, ParsedTemplateInfo(), AS, DSC_top_level);
878 
879   // If we had a free-standing type definition with a missing semicolon, we
880   // may get this far before the problem becomes obvious.
881   if (DS.hasTagDefinition() &&
882       DiagnoseMissingSemiAfterTagDefinition(DS, AS, DSC_top_level))
883     return nullptr;
884 
885   // C99 6.7.2.3p6: Handle "struct-or-union identifier;", "enum { X };"
886   // declaration-specifiers init-declarator-list[opt] ';'
887   if (Tok.is(tok::semi)) {
888     ProhibitAttributes(attrs);
889     ConsumeToken();
890     RecordDecl *AnonRecord = nullptr;
891     Decl *TheDecl = Actions.ParsedFreeStandingDeclSpec(getCurScope(), AS_none,
892                                                        DS, AnonRecord);
893     DS.complete(TheDecl);
894     if (AnonRecord) {
895       Decl* decls[] = {AnonRecord, TheDecl};
896       return Actions.BuildDeclaratorGroup(decls, /*TypeMayContainAuto=*/false);
897     }
898     return Actions.ConvertDeclToDeclGroup(TheDecl);
899   }
900 
901   DS.takeAttributesFrom(attrs);
902 
903   // ObjC2 allows prefix attributes on class interfaces and protocols.
904   // FIXME: This still needs better diagnostics. We should only accept
905   // attributes here, no types, etc.
906   if (getLangOpts().ObjC2 && Tok.is(tok::at)) {
907     SourceLocation AtLoc = ConsumeToken(); // the "@"
908     if (!Tok.isObjCAtKeyword(tok::objc_interface) &&
909         !Tok.isObjCAtKeyword(tok::objc_protocol)) {
910       Diag(Tok, diag::err_objc_unexpected_attr);
911       SkipUntil(tok::semi); // FIXME: better skip?
912       return nullptr;
913     }
914 
915     DS.abort();
916 
917     const char *PrevSpec = nullptr;
918     unsigned DiagID;
919     if (DS.SetTypeSpecType(DeclSpec::TST_unspecified, AtLoc, PrevSpec, DiagID,
920                            Actions.getASTContext().getPrintingPolicy()))
921       Diag(AtLoc, DiagID) << PrevSpec;
922 
923     if (Tok.isObjCAtKeyword(tok::objc_protocol))
924       return ParseObjCAtProtocolDeclaration(AtLoc, DS.getAttributes());
925 
926     return Actions.ConvertDeclToDeclGroup(
927             ParseObjCAtInterfaceDeclaration(AtLoc, DS.getAttributes()));
928   }
929 
930   // If the declspec consisted only of 'extern' and we have a string
931   // literal following it, this must be a C++ linkage specifier like
932   // 'extern "C"'.
933   if (getLangOpts().CPlusPlus && isTokenStringLiteral() &&
934       DS.getStorageClassSpec() == DeclSpec::SCS_extern &&
935       DS.getParsedSpecifiers() == DeclSpec::PQ_StorageClassSpecifier) {
936     Decl *TheDecl = ParseLinkage(DS, Declarator::FileContext);
937     return Actions.ConvertDeclToDeclGroup(TheDecl);
938   }
939 
940   return ParseDeclGroup(DS, Declarator::FileContext);
941 }
942 
943 Parser::DeclGroupPtrTy
ParseDeclarationOrFunctionDefinition(ParsedAttributesWithRange & attrs,ParsingDeclSpec * DS,AccessSpecifier AS)944 Parser::ParseDeclarationOrFunctionDefinition(ParsedAttributesWithRange &attrs,
945                                              ParsingDeclSpec *DS,
946                                              AccessSpecifier AS) {
947   if (DS) {
948     return ParseDeclOrFunctionDefInternal(attrs, *DS, AS);
949   } else {
950     ParsingDeclSpec PDS(*this);
951     // Must temporarily exit the objective-c container scope for
952     // parsing c constructs and re-enter objc container scope
953     // afterwards.
954     ObjCDeclContextSwitch ObjCDC(*this);
955 
956     return ParseDeclOrFunctionDefInternal(attrs, PDS, AS);
957   }
958 }
959 
960 /// ParseFunctionDefinition - We parsed and verified that the specified
961 /// Declarator is well formed.  If this is a K&R-style function, read the
962 /// parameters declaration-list, then start the compound-statement.
963 ///
964 ///       function-definition: [C99 6.9.1]
965 ///         decl-specs      declarator declaration-list[opt] compound-statement
966 /// [C90] function-definition: [C99 6.7.1] - implicit int result
967 /// [C90]   decl-specs[opt] declarator declaration-list[opt] compound-statement
968 /// [C++] function-definition: [C++ 8.4]
969 ///         decl-specifier-seq[opt] declarator ctor-initializer[opt]
970 ///         function-body
971 /// [C++] function-definition: [C++ 8.4]
972 ///         decl-specifier-seq[opt] declarator function-try-block
973 ///
ParseFunctionDefinition(ParsingDeclarator & D,const ParsedTemplateInfo & TemplateInfo,LateParsedAttrList * LateParsedAttrs)974 Decl *Parser::ParseFunctionDefinition(ParsingDeclarator &D,
975                                       const ParsedTemplateInfo &TemplateInfo,
976                                       LateParsedAttrList *LateParsedAttrs) {
977   // Poison SEH identifiers so they are flagged as illegal in function bodies.
978   PoisonSEHIdentifiersRAIIObject PoisonSEHIdentifiers(*this, true);
979   const DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
980 
981   // If this is C90 and the declspecs were completely missing, fudge in an
982   // implicit int.  We do this here because this is the only place where
983   // declaration-specifiers are completely optional in the grammar.
984   if (getLangOpts().ImplicitInt && D.getDeclSpec().isEmpty()) {
985     const char *PrevSpec;
986     unsigned DiagID;
987     const PrintingPolicy &Policy = Actions.getASTContext().getPrintingPolicy();
988     D.getMutableDeclSpec().SetTypeSpecType(DeclSpec::TST_int,
989                                            D.getIdentifierLoc(),
990                                            PrevSpec, DiagID,
991                                            Policy);
992     D.SetRangeBegin(D.getDeclSpec().getSourceRange().getBegin());
993   }
994 
995   // If this declaration was formed with a K&R-style identifier list for the
996   // arguments, parse declarations for all of the args next.
997   // int foo(a,b) int a; float b; {}
998   if (FTI.isKNRPrototype())
999     ParseKNRParamDeclarations(D);
1000 
1001   // We should have either an opening brace or, in a C++ constructor,
1002   // we may have a colon.
1003   if (Tok.isNot(tok::l_brace) &&
1004       (!getLangOpts().CPlusPlus ||
1005        (Tok.isNot(tok::colon) && Tok.isNot(tok::kw_try) &&
1006         Tok.isNot(tok::equal)))) {
1007     Diag(Tok, diag::err_expected_fn_body);
1008 
1009     // Skip over garbage, until we get to '{'.  Don't eat the '{'.
1010     SkipUntil(tok::l_brace, StopAtSemi | StopBeforeMatch);
1011 
1012     // If we didn't find the '{', bail out.
1013     if (Tok.isNot(tok::l_brace))
1014       return nullptr;
1015   }
1016 
1017   // Check to make sure that any normal attributes are allowed to be on
1018   // a definition.  Late parsed attributes are checked at the end.
1019   if (Tok.isNot(tok::equal)) {
1020     AttributeList *DtorAttrs = D.getAttributes();
1021     while (DtorAttrs) {
1022       if (DtorAttrs->isKnownToGCC() &&
1023           !DtorAttrs->isCXX11Attribute()) {
1024         Diag(DtorAttrs->getLoc(), diag::warn_attribute_on_function_definition)
1025           << DtorAttrs->getName();
1026       }
1027       DtorAttrs = DtorAttrs->getNext();
1028     }
1029   }
1030 
1031   // In delayed template parsing mode, for function template we consume the
1032   // tokens and store them for late parsing at the end of the translation unit.
1033   if (getLangOpts().DelayedTemplateParsing && Tok.isNot(tok::equal) &&
1034       TemplateInfo.Kind == ParsedTemplateInfo::Template &&
1035       Actions.canDelayFunctionBody(D)) {
1036     MultiTemplateParamsArg TemplateParameterLists(*TemplateInfo.TemplateParams);
1037 
1038     ParseScope BodyScope(this, Scope::FnScope|Scope::DeclScope);
1039     Scope *ParentScope = getCurScope()->getParent();
1040 
1041     D.setFunctionDefinitionKind(FDK_Definition);
1042     Decl *DP = Actions.HandleDeclarator(ParentScope, D,
1043                                         TemplateParameterLists);
1044     D.complete(DP);
1045     D.getMutableDeclSpec().abort();
1046 
1047     if (SkipFunctionBodies && (!DP || Actions.canSkipFunctionBody(DP)) &&
1048         trySkippingFunctionBody()) {
1049       BodyScope.Exit();
1050       return Actions.ActOnSkippedFunctionBody(DP);
1051     }
1052 
1053     CachedTokens Toks;
1054     LexTemplateFunctionForLateParsing(Toks);
1055 
1056     if (DP) {
1057       FunctionDecl *FnD = DP->getAsFunction();
1058       Actions.CheckForFunctionRedefinition(FnD);
1059       Actions.MarkAsLateParsedTemplate(FnD, DP, Toks);
1060     }
1061     return DP;
1062   }
1063   else if (CurParsedObjCImpl &&
1064            !TemplateInfo.TemplateParams &&
1065            (Tok.is(tok::l_brace) || Tok.is(tok::kw_try) ||
1066             Tok.is(tok::colon)) &&
1067       Actions.CurContext->isTranslationUnit()) {
1068     ParseScope BodyScope(this, Scope::FnScope|Scope::DeclScope);
1069     Scope *ParentScope = getCurScope()->getParent();
1070 
1071     D.setFunctionDefinitionKind(FDK_Definition);
1072     Decl *FuncDecl = Actions.HandleDeclarator(ParentScope, D,
1073                                               MultiTemplateParamsArg());
1074     D.complete(FuncDecl);
1075     D.getMutableDeclSpec().abort();
1076     if (FuncDecl) {
1077       // Consume the tokens and store them for later parsing.
1078       StashAwayMethodOrFunctionBodyTokens(FuncDecl);
1079       CurParsedObjCImpl->HasCFunction = true;
1080       return FuncDecl;
1081     }
1082     // FIXME: Should we really fall through here?
1083   }
1084 
1085   // Enter a scope for the function body.
1086   ParseScope BodyScope(this, Scope::FnScope|Scope::DeclScope);
1087 
1088   // Tell the actions module that we have entered a function definition with the
1089   // specified Declarator for the function.
1090   Sema::SkipBodyInfo SkipBody;
1091   Decl *Res = Actions.ActOnStartOfFunctionDef(getCurScope(), D,
1092                                               TemplateInfo.TemplateParams
1093                                                   ? *TemplateInfo.TemplateParams
1094                                                   : MultiTemplateParamsArg(),
1095                                               &SkipBody);
1096 
1097   if (SkipBody.ShouldSkip) {
1098     SkipFunctionBody();
1099     return Res;
1100   }
1101 
1102   // Break out of the ParsingDeclarator context before we parse the body.
1103   D.complete(Res);
1104 
1105   // Break out of the ParsingDeclSpec context, too.  This const_cast is
1106   // safe because we're always the sole owner.
1107   D.getMutableDeclSpec().abort();
1108 
1109   if (TryConsumeToken(tok::equal)) {
1110     assert(getLangOpts().CPlusPlus && "Only C++ function definitions have '='");
1111 
1112     bool Delete = false;
1113     SourceLocation KWLoc;
1114     if (TryConsumeToken(tok::kw_delete, KWLoc)) {
1115       Diag(KWLoc, getLangOpts().CPlusPlus11
1116                       ? diag::warn_cxx98_compat_defaulted_deleted_function
1117                       : diag::ext_defaulted_deleted_function)
1118         << 1 /* deleted */;
1119       Actions.SetDeclDeleted(Res, KWLoc);
1120       Delete = true;
1121     } else if (TryConsumeToken(tok::kw_default, KWLoc)) {
1122       Diag(KWLoc, getLangOpts().CPlusPlus11
1123                       ? diag::warn_cxx98_compat_defaulted_deleted_function
1124                       : diag::ext_defaulted_deleted_function)
1125         << 0 /* defaulted */;
1126       Actions.SetDeclDefaulted(Res, KWLoc);
1127     } else {
1128       llvm_unreachable("function definition after = not 'delete' or 'default'");
1129     }
1130 
1131     if (Tok.is(tok::comma)) {
1132       Diag(KWLoc, diag::err_default_delete_in_multiple_declaration)
1133         << Delete;
1134       SkipUntil(tok::semi);
1135     } else if (ExpectAndConsume(tok::semi, diag::err_expected_after,
1136                                 Delete ? "delete" : "default")) {
1137       SkipUntil(tok::semi);
1138     }
1139 
1140     Stmt *GeneratedBody = Res ? Res->getBody() : nullptr;
1141     Actions.ActOnFinishFunctionBody(Res, GeneratedBody, false);
1142     return Res;
1143   }
1144 
1145   if (SkipFunctionBodies && (!Res || Actions.canSkipFunctionBody(Res)) &&
1146       trySkippingFunctionBody()) {
1147     BodyScope.Exit();
1148     Actions.ActOnSkippedFunctionBody(Res);
1149     return Actions.ActOnFinishFunctionBody(Res, nullptr, false);
1150   }
1151 
1152   if (Tok.is(tok::kw_try))
1153     return ParseFunctionTryBlock(Res, BodyScope);
1154 
1155   // If we have a colon, then we're probably parsing a C++
1156   // ctor-initializer.
1157   if (Tok.is(tok::colon)) {
1158     ParseConstructorInitializer(Res);
1159 
1160     // Recover from error.
1161     if (!Tok.is(tok::l_brace)) {
1162       BodyScope.Exit();
1163       Actions.ActOnFinishFunctionBody(Res, nullptr);
1164       return Res;
1165     }
1166   } else
1167     Actions.ActOnDefaultCtorInitializers(Res);
1168 
1169   // Late attributes are parsed in the same scope as the function body.
1170   if (LateParsedAttrs)
1171     ParseLexedAttributeList(*LateParsedAttrs, Res, false, true);
1172 
1173   return ParseFunctionStatementBody(Res, BodyScope);
1174 }
1175 
SkipFunctionBody()1176 void Parser::SkipFunctionBody() {
1177   if (Tok.is(tok::equal)) {
1178     SkipUntil(tok::semi);
1179     return;
1180   }
1181 
1182   bool IsFunctionTryBlock = Tok.is(tok::kw_try);
1183   if (IsFunctionTryBlock)
1184     ConsumeToken();
1185 
1186   CachedTokens Skipped;
1187   if (ConsumeAndStoreFunctionPrologue(Skipped))
1188     SkipMalformedDecl();
1189   else {
1190     SkipUntil(tok::r_brace);
1191     while (IsFunctionTryBlock && Tok.is(tok::kw_catch)) {
1192       SkipUntil(tok::l_brace);
1193       SkipUntil(tok::r_brace);
1194     }
1195   }
1196 }
1197 
1198 /// ParseKNRParamDeclarations - Parse 'declaration-list[opt]' which provides
1199 /// types for a function with a K&R-style identifier list for arguments.
ParseKNRParamDeclarations(Declarator & D)1200 void Parser::ParseKNRParamDeclarations(Declarator &D) {
1201   // We know that the top-level of this declarator is a function.
1202   DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
1203 
1204   // Enter function-declaration scope, limiting any declarators to the
1205   // function prototype scope, including parameter declarators.
1206   ParseScope PrototypeScope(this, Scope::FunctionPrototypeScope |
1207                             Scope::FunctionDeclarationScope | Scope::DeclScope);
1208 
1209   // Read all the argument declarations.
1210   while (isDeclarationSpecifier()) {
1211     SourceLocation DSStart = Tok.getLocation();
1212 
1213     // Parse the common declaration-specifiers piece.
1214     DeclSpec DS(AttrFactory);
1215     ParseDeclarationSpecifiers(DS);
1216 
1217     // C99 6.9.1p6: 'each declaration in the declaration list shall have at
1218     // least one declarator'.
1219     // NOTE: GCC just makes this an ext-warn.  It's not clear what it does with
1220     // the declarations though.  It's trivial to ignore them, really hard to do
1221     // anything else with them.
1222     if (TryConsumeToken(tok::semi)) {
1223       Diag(DSStart, diag::err_declaration_does_not_declare_param);
1224       continue;
1225     }
1226 
1227     // C99 6.9.1p6: Declarations shall contain no storage-class specifiers other
1228     // than register.
1229     if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified &&
1230         DS.getStorageClassSpec() != DeclSpec::SCS_register) {
1231       Diag(DS.getStorageClassSpecLoc(),
1232            diag::err_invalid_storage_class_in_func_decl);
1233       DS.ClearStorageClassSpecs();
1234     }
1235     if (DS.getThreadStorageClassSpec() != DeclSpec::TSCS_unspecified) {
1236       Diag(DS.getThreadStorageClassSpecLoc(),
1237            diag::err_invalid_storage_class_in_func_decl);
1238       DS.ClearStorageClassSpecs();
1239     }
1240 
1241     // Parse the first declarator attached to this declspec.
1242     Declarator ParmDeclarator(DS, Declarator::KNRTypeListContext);
1243     ParseDeclarator(ParmDeclarator);
1244 
1245     // Handle the full declarator list.
1246     while (1) {
1247       // If attributes are present, parse them.
1248       MaybeParseGNUAttributes(ParmDeclarator);
1249 
1250       // Ask the actions module to compute the type for this declarator.
1251       Decl *Param =
1252         Actions.ActOnParamDeclarator(getCurScope(), ParmDeclarator);
1253 
1254       if (Param &&
1255           // A missing identifier has already been diagnosed.
1256           ParmDeclarator.getIdentifier()) {
1257 
1258         // Scan the argument list looking for the correct param to apply this
1259         // type.
1260         for (unsigned i = 0; ; ++i) {
1261           // C99 6.9.1p6: those declarators shall declare only identifiers from
1262           // the identifier list.
1263           if (i == FTI.NumParams) {
1264             Diag(ParmDeclarator.getIdentifierLoc(), diag::err_no_matching_param)
1265               << ParmDeclarator.getIdentifier();
1266             break;
1267           }
1268 
1269           if (FTI.Params[i].Ident == ParmDeclarator.getIdentifier()) {
1270             // Reject redefinitions of parameters.
1271             if (FTI.Params[i].Param) {
1272               Diag(ParmDeclarator.getIdentifierLoc(),
1273                    diag::err_param_redefinition)
1274                  << ParmDeclarator.getIdentifier();
1275             } else {
1276               FTI.Params[i].Param = Param;
1277             }
1278             break;
1279           }
1280         }
1281       }
1282 
1283       // If we don't have a comma, it is either the end of the list (a ';') or
1284       // an error, bail out.
1285       if (Tok.isNot(tok::comma))
1286         break;
1287 
1288       ParmDeclarator.clear();
1289 
1290       // Consume the comma.
1291       ParmDeclarator.setCommaLoc(ConsumeToken());
1292 
1293       // Parse the next declarator.
1294       ParseDeclarator(ParmDeclarator);
1295     }
1296 
1297     // Consume ';' and continue parsing.
1298     if (!ExpectAndConsumeSemi(diag::err_expected_semi_declaration))
1299       continue;
1300 
1301     // Otherwise recover by skipping to next semi or mandatory function body.
1302     if (SkipUntil(tok::l_brace, StopAtSemi | StopBeforeMatch))
1303       break;
1304     TryConsumeToken(tok::semi);
1305   }
1306 
1307   // The actions module must verify that all arguments were declared.
1308   Actions.ActOnFinishKNRParamDeclarations(getCurScope(), D, Tok.getLocation());
1309 }
1310 
1311 
1312 /// ParseAsmStringLiteral - This is just a normal string-literal, but is not
1313 /// allowed to be a wide string, and is not subject to character translation.
1314 ///
1315 /// [GNU] asm-string-literal:
1316 ///         string-literal
1317 ///
ParseAsmStringLiteral()1318 ExprResult Parser::ParseAsmStringLiteral() {
1319   if (!isTokenStringLiteral()) {
1320     Diag(Tok, diag::err_expected_string_literal)
1321       << /*Source='in...'*/0 << "'asm'";
1322     return ExprError();
1323   }
1324 
1325   ExprResult AsmString(ParseStringLiteralExpression());
1326   if (!AsmString.isInvalid()) {
1327     const auto *SL = cast<StringLiteral>(AsmString.get());
1328     if (!SL->isAscii()) {
1329       Diag(Tok, diag::err_asm_operand_wide_string_literal)
1330         << SL->isWide()
1331         << SL->getSourceRange();
1332       return ExprError();
1333     }
1334   }
1335   return AsmString;
1336 }
1337 
1338 /// ParseSimpleAsm
1339 ///
1340 /// [GNU] simple-asm-expr:
1341 ///         'asm' '(' asm-string-literal ')'
1342 ///
ParseSimpleAsm(SourceLocation * EndLoc)1343 ExprResult Parser::ParseSimpleAsm(SourceLocation *EndLoc) {
1344   assert(Tok.is(tok::kw_asm) && "Not an asm!");
1345   SourceLocation Loc = ConsumeToken();
1346 
1347   if (Tok.is(tok::kw_volatile)) {
1348     // Remove from the end of 'asm' to the end of 'volatile'.
1349     SourceRange RemovalRange(PP.getLocForEndOfToken(Loc),
1350                              PP.getLocForEndOfToken(Tok.getLocation()));
1351 
1352     Diag(Tok, diag::warn_file_asm_volatile)
1353       << FixItHint::CreateRemoval(RemovalRange);
1354     ConsumeToken();
1355   }
1356 
1357   BalancedDelimiterTracker T(*this, tok::l_paren);
1358   if (T.consumeOpen()) {
1359     Diag(Tok, diag::err_expected_lparen_after) << "asm";
1360     return ExprError();
1361   }
1362 
1363   ExprResult Result(ParseAsmStringLiteral());
1364 
1365   if (!Result.isInvalid()) {
1366     // Close the paren and get the location of the end bracket
1367     T.consumeClose();
1368     if (EndLoc)
1369       *EndLoc = T.getCloseLocation();
1370   } else if (SkipUntil(tok::r_paren, StopAtSemi | StopBeforeMatch)) {
1371     if (EndLoc)
1372       *EndLoc = Tok.getLocation();
1373     ConsumeParen();
1374   }
1375 
1376   return Result;
1377 }
1378 
1379 /// \brief Get the TemplateIdAnnotation from the token and put it in the
1380 /// cleanup pool so that it gets destroyed when parsing the current top level
1381 /// declaration is finished.
takeTemplateIdAnnotation(const Token & tok)1382 TemplateIdAnnotation *Parser::takeTemplateIdAnnotation(const Token &tok) {
1383   assert(tok.is(tok::annot_template_id) && "Expected template-id token");
1384   TemplateIdAnnotation *
1385       Id = static_cast<TemplateIdAnnotation *>(tok.getAnnotationValue());
1386   return Id;
1387 }
1388 
AnnotateScopeToken(CXXScopeSpec & SS,bool IsNewAnnotation)1389 void Parser::AnnotateScopeToken(CXXScopeSpec &SS, bool IsNewAnnotation) {
1390   // Push the current token back into the token stream (or revert it if it is
1391   // cached) and use an annotation scope token for current token.
1392   if (PP.isBacktrackEnabled())
1393     PP.RevertCachedTokens(1);
1394   else
1395     PP.EnterToken(Tok);
1396   Tok.setKind(tok::annot_cxxscope);
1397   Tok.setAnnotationValue(Actions.SaveNestedNameSpecifierAnnotation(SS));
1398   Tok.setAnnotationRange(SS.getRange());
1399 
1400   // In case the tokens were cached, have Preprocessor replace them
1401   // with the annotation token.  We don't need to do this if we've
1402   // just reverted back to a prior state.
1403   if (IsNewAnnotation)
1404     PP.AnnotateCachedTokens(Tok);
1405 }
1406 
1407 /// \brief Attempt to classify the name at the current token position. This may
1408 /// form a type, scope or primary expression annotation, or replace the token
1409 /// with a typo-corrected keyword. This is only appropriate when the current
1410 /// name must refer to an entity which has already been declared.
1411 ///
1412 /// \param IsAddressOfOperand Must be \c true if the name is preceded by an '&'
1413 ///        and might possibly have a dependent nested name specifier.
1414 /// \param CCC Indicates how to perform typo-correction for this name. If NULL,
1415 ///        no typo correction will be performed.
1416 Parser::AnnotatedNameKind
TryAnnotateName(bool IsAddressOfOperand,std::unique_ptr<CorrectionCandidateCallback> CCC)1417 Parser::TryAnnotateName(bool IsAddressOfOperand,
1418                         std::unique_ptr<CorrectionCandidateCallback> CCC) {
1419   assert(Tok.is(tok::identifier) || Tok.is(tok::annot_cxxscope));
1420 
1421   const bool EnteringContext = false;
1422   const bool WasScopeAnnotation = Tok.is(tok::annot_cxxscope);
1423 
1424   CXXScopeSpec SS;
1425   if (getLangOpts().CPlusPlus &&
1426       ParseOptionalCXXScopeSpecifier(SS, nullptr, EnteringContext))
1427     return ANK_Error;
1428 
1429   if (Tok.isNot(tok::identifier) || SS.isInvalid()) {
1430     if (TryAnnotateTypeOrScopeTokenAfterScopeSpec(EnteringContext, false, SS,
1431                                                   !WasScopeAnnotation))
1432       return ANK_Error;
1433     return ANK_Unresolved;
1434   }
1435 
1436   IdentifierInfo *Name = Tok.getIdentifierInfo();
1437   SourceLocation NameLoc = Tok.getLocation();
1438 
1439   // FIXME: Move the tentative declaration logic into ClassifyName so we can
1440   // typo-correct to tentatively-declared identifiers.
1441   if (isTentativelyDeclared(Name)) {
1442     // Identifier has been tentatively declared, and thus cannot be resolved as
1443     // an expression. Fall back to annotating it as a type.
1444     if (TryAnnotateTypeOrScopeTokenAfterScopeSpec(EnteringContext, false, SS,
1445                                                   !WasScopeAnnotation))
1446       return ANK_Error;
1447     return Tok.is(tok::annot_typename) ? ANK_Success : ANK_TentativeDecl;
1448   }
1449 
1450   Token Next = NextToken();
1451 
1452   // Look up and classify the identifier. We don't perform any typo-correction
1453   // after a scope specifier, because in general we can't recover from typos
1454   // there (eg, after correcting 'A::tempalte B<X>::C' [sic], we would need to
1455   // jump back into scope specifier parsing).
1456   Sema::NameClassification Classification = Actions.ClassifyName(
1457       getCurScope(), SS, Name, NameLoc, Next, IsAddressOfOperand,
1458       SS.isEmpty() ? std::move(CCC) : nullptr);
1459 
1460   switch (Classification.getKind()) {
1461   case Sema::NC_Error:
1462     return ANK_Error;
1463 
1464   case Sema::NC_Keyword:
1465     // The identifier was typo-corrected to a keyword.
1466     Tok.setIdentifierInfo(Name);
1467     Tok.setKind(Name->getTokenID());
1468     PP.TypoCorrectToken(Tok);
1469     if (SS.isNotEmpty())
1470       AnnotateScopeToken(SS, !WasScopeAnnotation);
1471     // We've "annotated" this as a keyword.
1472     return ANK_Success;
1473 
1474   case Sema::NC_Unknown:
1475     // It's not something we know about. Leave it unannotated.
1476     break;
1477 
1478   case Sema::NC_Type: {
1479     SourceLocation BeginLoc = NameLoc;
1480     if (SS.isNotEmpty())
1481       BeginLoc = SS.getBeginLoc();
1482 
1483     /// An Objective-C object type followed by '<' is a specialization of
1484     /// a parameterized class type or a protocol-qualified type.
1485     ParsedType Ty = Classification.getType();
1486     if (getLangOpts().ObjC1 && NextToken().is(tok::less) &&
1487         (Ty.get()->isObjCObjectType() ||
1488          Ty.get()->isObjCObjectPointerType())) {
1489       // Consume the name.
1490       SourceLocation IdentifierLoc = ConsumeToken();
1491       SourceLocation NewEndLoc;
1492       TypeResult NewType
1493           = parseObjCTypeArgsAndProtocolQualifiers(IdentifierLoc, Ty,
1494                                                    /*consumeLastToken=*/false,
1495                                                    NewEndLoc);
1496       if (NewType.isUsable())
1497         Ty = NewType.get();
1498     }
1499 
1500     Tok.setKind(tok::annot_typename);
1501     setTypeAnnotation(Tok, Ty);
1502     Tok.setAnnotationEndLoc(Tok.getLocation());
1503     Tok.setLocation(BeginLoc);
1504     PP.AnnotateCachedTokens(Tok);
1505     return ANK_Success;
1506   }
1507 
1508   case Sema::NC_Expression:
1509     Tok.setKind(tok::annot_primary_expr);
1510     setExprAnnotation(Tok, Classification.getExpression());
1511     Tok.setAnnotationEndLoc(NameLoc);
1512     if (SS.isNotEmpty())
1513       Tok.setLocation(SS.getBeginLoc());
1514     PP.AnnotateCachedTokens(Tok);
1515     return ANK_Success;
1516 
1517   case Sema::NC_TypeTemplate:
1518     if (Next.isNot(tok::less)) {
1519       // This may be a type template being used as a template template argument.
1520       if (SS.isNotEmpty())
1521         AnnotateScopeToken(SS, !WasScopeAnnotation);
1522       return ANK_TemplateName;
1523     }
1524     // Fall through.
1525   case Sema::NC_VarTemplate:
1526   case Sema::NC_FunctionTemplate: {
1527     // We have a type, variable or function template followed by '<'.
1528     ConsumeToken();
1529     UnqualifiedId Id;
1530     Id.setIdentifier(Name, NameLoc);
1531     if (AnnotateTemplateIdToken(
1532             TemplateTy::make(Classification.getTemplateName()),
1533             Classification.getTemplateNameKind(), SS, SourceLocation(), Id))
1534       return ANK_Error;
1535     return ANK_Success;
1536   }
1537 
1538   case Sema::NC_NestedNameSpecifier:
1539     llvm_unreachable("already parsed nested name specifier");
1540   }
1541 
1542   // Unable to classify the name, but maybe we can annotate a scope specifier.
1543   if (SS.isNotEmpty())
1544     AnnotateScopeToken(SS, !WasScopeAnnotation);
1545   return ANK_Unresolved;
1546 }
1547 
TryKeywordIdentFallback(bool DisableKeyword)1548 bool Parser::TryKeywordIdentFallback(bool DisableKeyword) {
1549   assert(Tok.isNot(tok::identifier));
1550   Diag(Tok, diag::ext_keyword_as_ident)
1551     << PP.getSpelling(Tok)
1552     << DisableKeyword;
1553   if (DisableKeyword)
1554     Tok.getIdentifierInfo()->revertTokenIDToIdentifier();
1555   Tok.setKind(tok::identifier);
1556   return true;
1557 }
1558 
1559 /// TryAnnotateTypeOrScopeToken - If the current token position is on a
1560 /// typename (possibly qualified in C++) or a C++ scope specifier not followed
1561 /// by a typename, TryAnnotateTypeOrScopeToken will replace one or more tokens
1562 /// with a single annotation token representing the typename or C++ scope
1563 /// respectively.
1564 /// This simplifies handling of C++ scope specifiers and allows efficient
1565 /// backtracking without the need to re-parse and resolve nested-names and
1566 /// typenames.
1567 /// It will mainly be called when we expect to treat identifiers as typenames
1568 /// (if they are typenames). For example, in C we do not expect identifiers
1569 /// inside expressions to be treated as typenames so it will not be called
1570 /// for expressions in C.
1571 /// The benefit for C/ObjC is that a typename will be annotated and
1572 /// Actions.getTypeName will not be needed to be called again (e.g. getTypeName
1573 /// will not be called twice, once to check whether we have a declaration
1574 /// specifier, and another one to get the actual type inside
1575 /// ParseDeclarationSpecifiers).
1576 ///
1577 /// This returns true if an error occurred.
1578 ///
1579 /// Note that this routine emits an error if you call it with ::new or ::delete
1580 /// as the current tokens, so only call it in contexts where these are invalid.
TryAnnotateTypeOrScopeToken(bool EnteringContext,bool NeedType)1581 bool Parser::TryAnnotateTypeOrScopeToken(bool EnteringContext, bool NeedType) {
1582   assert((Tok.is(tok::identifier) || Tok.is(tok::coloncolon) ||
1583           Tok.is(tok::kw_typename) || Tok.is(tok::annot_cxxscope) ||
1584           Tok.is(tok::kw_decltype) || Tok.is(tok::annot_template_id) ||
1585           Tok.is(tok::kw___super)) &&
1586          "Cannot be a type or scope token!");
1587 
1588   if (Tok.is(tok::kw_typename)) {
1589     // MSVC lets you do stuff like:
1590     //   typename typedef T_::D D;
1591     //
1592     // We will consume the typedef token here and put it back after we have
1593     // parsed the first identifier, transforming it into something more like:
1594     //   typename T_::D typedef D;
1595     if (getLangOpts().MSVCCompat && NextToken().is(tok::kw_typedef)) {
1596       Token TypedefToken;
1597       PP.Lex(TypedefToken);
1598       bool Result = TryAnnotateTypeOrScopeToken(EnteringContext, NeedType);
1599       PP.EnterToken(Tok);
1600       Tok = TypedefToken;
1601       if (!Result)
1602         Diag(Tok.getLocation(), diag::warn_expected_qualified_after_typename);
1603       return Result;
1604     }
1605 
1606     // Parse a C++ typename-specifier, e.g., "typename T::type".
1607     //
1608     //   typename-specifier:
1609     //     'typename' '::' [opt] nested-name-specifier identifier
1610     //     'typename' '::' [opt] nested-name-specifier template [opt]
1611     //            simple-template-id
1612     SourceLocation TypenameLoc = ConsumeToken();
1613     CXXScopeSpec SS;
1614     if (ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
1615                                        /*EnteringContext=*/false, nullptr,
1616                                        /*IsTypename*/ true))
1617       return true;
1618     if (!SS.isSet()) {
1619       if (Tok.is(tok::identifier) || Tok.is(tok::annot_template_id) ||
1620           Tok.is(tok::annot_decltype)) {
1621         // Attempt to recover by skipping the invalid 'typename'
1622         if (Tok.is(tok::annot_decltype) ||
1623             (!TryAnnotateTypeOrScopeToken(EnteringContext, NeedType) &&
1624              Tok.isAnnotation())) {
1625           unsigned DiagID = diag::err_expected_qualified_after_typename;
1626           // MS compatibility: MSVC permits using known types with typename.
1627           // e.g. "typedef typename T* pointer_type"
1628           if (getLangOpts().MicrosoftExt)
1629             DiagID = diag::warn_expected_qualified_after_typename;
1630           Diag(Tok.getLocation(), DiagID);
1631           return false;
1632         }
1633       }
1634 
1635       Diag(Tok.getLocation(), diag::err_expected_qualified_after_typename);
1636       return true;
1637     }
1638 
1639     TypeResult Ty;
1640     if (Tok.is(tok::identifier)) {
1641       // FIXME: check whether the next token is '<', first!
1642       Ty = Actions.ActOnTypenameType(getCurScope(), TypenameLoc, SS,
1643                                      *Tok.getIdentifierInfo(),
1644                                      Tok.getLocation());
1645     } else if (Tok.is(tok::annot_template_id)) {
1646       TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok);
1647       if (TemplateId->Kind != TNK_Type_template &&
1648           TemplateId->Kind != TNK_Dependent_template_name) {
1649         Diag(Tok, diag::err_typename_refers_to_non_type_template)
1650           << Tok.getAnnotationRange();
1651         return true;
1652       }
1653 
1654       ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
1655                                          TemplateId->NumArgs);
1656 
1657       Ty = Actions.ActOnTypenameType(getCurScope(), TypenameLoc, SS,
1658                                      TemplateId->TemplateKWLoc,
1659                                      TemplateId->Template,
1660                                      TemplateId->TemplateNameLoc,
1661                                      TemplateId->LAngleLoc,
1662                                      TemplateArgsPtr,
1663                                      TemplateId->RAngleLoc);
1664     } else {
1665       Diag(Tok, diag::err_expected_type_name_after_typename)
1666         << SS.getRange();
1667       return true;
1668     }
1669 
1670     SourceLocation EndLoc = Tok.getLastLoc();
1671     Tok.setKind(tok::annot_typename);
1672     setTypeAnnotation(Tok, Ty.isInvalid() ? nullptr : Ty.get());
1673     Tok.setAnnotationEndLoc(EndLoc);
1674     Tok.setLocation(TypenameLoc);
1675     PP.AnnotateCachedTokens(Tok);
1676     return false;
1677   }
1678 
1679   // Remembers whether the token was originally a scope annotation.
1680   bool WasScopeAnnotation = Tok.is(tok::annot_cxxscope);
1681 
1682   CXXScopeSpec SS;
1683   if (getLangOpts().CPlusPlus)
1684     if (ParseOptionalCXXScopeSpecifier(SS, nullptr, EnteringContext))
1685       return true;
1686 
1687   return TryAnnotateTypeOrScopeTokenAfterScopeSpec(EnteringContext, NeedType,
1688                                                    SS, !WasScopeAnnotation);
1689 }
1690 
1691 /// \brief Try to annotate a type or scope token, having already parsed an
1692 /// optional scope specifier. \p IsNewScope should be \c true unless the scope
1693 /// specifier was extracted from an existing tok::annot_cxxscope annotation.
TryAnnotateTypeOrScopeTokenAfterScopeSpec(bool EnteringContext,bool NeedType,CXXScopeSpec & SS,bool IsNewScope)1694 bool Parser::TryAnnotateTypeOrScopeTokenAfterScopeSpec(bool EnteringContext,
1695                                                        bool NeedType,
1696                                                        CXXScopeSpec &SS,
1697                                                        bool IsNewScope) {
1698   if (Tok.is(tok::identifier)) {
1699     IdentifierInfo *CorrectedII = nullptr;
1700     // Determine whether the identifier is a type name.
1701     if (ParsedType Ty = Actions.getTypeName(
1702             *Tok.getIdentifierInfo(), Tok.getLocation(), getCurScope(), &SS,
1703             false, NextToken().is(tok::period), nullptr,
1704             /*IsCtorOrDtorName=*/false,
1705             /*NonTrivialTypeSourceInfo*/ true,
1706             NeedType ? &CorrectedII : nullptr)) {
1707       // A FixIt was applied as a result of typo correction
1708       if (CorrectedII)
1709         Tok.setIdentifierInfo(CorrectedII);
1710 
1711       SourceLocation BeginLoc = Tok.getLocation();
1712       if (SS.isNotEmpty()) // it was a C++ qualified type name.
1713         BeginLoc = SS.getBeginLoc();
1714 
1715       /// An Objective-C object type followed by '<' is a specialization of
1716       /// a parameterized class type or a protocol-qualified type.
1717       if (getLangOpts().ObjC1 && NextToken().is(tok::less) &&
1718           (Ty.get()->isObjCObjectType() ||
1719            Ty.get()->isObjCObjectPointerType())) {
1720         // Consume the name.
1721         SourceLocation IdentifierLoc = ConsumeToken();
1722         SourceLocation NewEndLoc;
1723         TypeResult NewType
1724           = parseObjCTypeArgsAndProtocolQualifiers(IdentifierLoc, Ty,
1725                                                    /*consumeLastToken=*/false,
1726                                                    NewEndLoc);
1727         if (NewType.isUsable())
1728           Ty = NewType.get();
1729       }
1730 
1731       // This is a typename. Replace the current token in-place with an
1732       // annotation type token.
1733       Tok.setKind(tok::annot_typename);
1734       setTypeAnnotation(Tok, Ty);
1735       Tok.setAnnotationEndLoc(Tok.getLocation());
1736       Tok.setLocation(BeginLoc);
1737 
1738       // In case the tokens were cached, have Preprocessor replace
1739       // them with the annotation token.
1740       PP.AnnotateCachedTokens(Tok);
1741       return false;
1742     }
1743 
1744     if (!getLangOpts().CPlusPlus) {
1745       // If we're in C, we can't have :: tokens at all (the lexer won't return
1746       // them).  If the identifier is not a type, then it can't be scope either,
1747       // just early exit.
1748       return false;
1749     }
1750 
1751     // If this is a template-id, annotate with a template-id or type token.
1752     if (NextToken().is(tok::less)) {
1753       TemplateTy Template;
1754       UnqualifiedId TemplateName;
1755       TemplateName.setIdentifier(Tok.getIdentifierInfo(), Tok.getLocation());
1756       bool MemberOfUnknownSpecialization;
1757       if (TemplateNameKind TNK =
1758               Actions.isTemplateName(getCurScope(), SS,
1759                                      /*hasTemplateKeyword=*/false, TemplateName,
1760                                      /*ObjectType=*/nullptr, EnteringContext,
1761                                      Template, MemberOfUnknownSpecialization)) {
1762         // Consume the identifier.
1763         ConsumeToken();
1764         if (AnnotateTemplateIdToken(Template, TNK, SS, SourceLocation(),
1765                                     TemplateName)) {
1766           // If an unrecoverable error occurred, we need to return true here,
1767           // because the token stream is in a damaged state.  We may not return
1768           // a valid identifier.
1769           return true;
1770         }
1771       }
1772     }
1773 
1774     // The current token, which is either an identifier or a
1775     // template-id, is not part of the annotation. Fall through to
1776     // push that token back into the stream and complete the C++ scope
1777     // specifier annotation.
1778   }
1779 
1780   if (Tok.is(tok::annot_template_id)) {
1781     TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok);
1782     if (TemplateId->Kind == TNK_Type_template) {
1783       // A template-id that refers to a type was parsed into a
1784       // template-id annotation in a context where we weren't allowed
1785       // to produce a type annotation token. Update the template-id
1786       // annotation token to a type annotation token now.
1787       AnnotateTemplateIdTokenAsType();
1788       return false;
1789     }
1790   }
1791 
1792   if (SS.isEmpty())
1793     return false;
1794 
1795   // A C++ scope specifier that isn't followed by a typename.
1796   AnnotateScopeToken(SS, IsNewScope);
1797   return false;
1798 }
1799 
1800 /// TryAnnotateScopeToken - Like TryAnnotateTypeOrScopeToken but only
1801 /// annotates C++ scope specifiers and template-ids.  This returns
1802 /// true if there was an error that could not be recovered from.
1803 ///
1804 /// Note that this routine emits an error if you call it with ::new or ::delete
1805 /// as the current tokens, so only call it in contexts where these are invalid.
TryAnnotateCXXScopeToken(bool EnteringContext)1806 bool Parser::TryAnnotateCXXScopeToken(bool EnteringContext) {
1807   assert(getLangOpts().CPlusPlus &&
1808          "Call sites of this function should be guarded by checking for C++");
1809   assert((Tok.is(tok::identifier) || Tok.is(tok::coloncolon) ||
1810           (Tok.is(tok::annot_template_id) && NextToken().is(tok::coloncolon)) ||
1811           Tok.is(tok::kw_decltype) || Tok.is(tok::kw___super)) &&
1812          "Cannot be a type or scope token!");
1813 
1814   CXXScopeSpec SS;
1815   if (ParseOptionalCXXScopeSpecifier(SS, nullptr, EnteringContext))
1816     return true;
1817   if (SS.isEmpty())
1818     return false;
1819 
1820   AnnotateScopeToken(SS, true);
1821   return false;
1822 }
1823 
isTokenEqualOrEqualTypo()1824 bool Parser::isTokenEqualOrEqualTypo() {
1825   tok::TokenKind Kind = Tok.getKind();
1826   switch (Kind) {
1827   default:
1828     return false;
1829   case tok::ampequal:            // &=
1830   case tok::starequal:           // *=
1831   case tok::plusequal:           // +=
1832   case tok::minusequal:          // -=
1833   case tok::exclaimequal:        // !=
1834   case tok::slashequal:          // /=
1835   case tok::percentequal:        // %=
1836   case tok::lessequal:           // <=
1837   case tok::lesslessequal:       // <<=
1838   case tok::greaterequal:        // >=
1839   case tok::greatergreaterequal: // >>=
1840   case tok::caretequal:          // ^=
1841   case tok::pipeequal:           // |=
1842   case tok::equalequal:          // ==
1843     Diag(Tok, diag::err_invalid_token_after_declarator_suggest_equal)
1844         << Kind
1845         << FixItHint::CreateReplacement(SourceRange(Tok.getLocation()), "=");
1846   case tok::equal:
1847     return true;
1848   }
1849 }
1850 
handleUnexpectedCodeCompletionToken()1851 SourceLocation Parser::handleUnexpectedCodeCompletionToken() {
1852   assert(Tok.is(tok::code_completion));
1853   PrevTokLocation = Tok.getLocation();
1854 
1855   for (Scope *S = getCurScope(); S; S = S->getParent()) {
1856     if (S->getFlags() & Scope::FnScope) {
1857       Actions.CodeCompleteOrdinaryName(getCurScope(),
1858                                        Sema::PCC_RecoveryInFunction);
1859       cutOffParsing();
1860       return PrevTokLocation;
1861     }
1862 
1863     if (S->getFlags() & Scope::ClassScope) {
1864       Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Class);
1865       cutOffParsing();
1866       return PrevTokLocation;
1867     }
1868   }
1869 
1870   Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Namespace);
1871   cutOffParsing();
1872   return PrevTokLocation;
1873 }
1874 
1875 // Code-completion pass-through functions
1876 
CodeCompleteDirective(bool InConditional)1877 void Parser::CodeCompleteDirective(bool InConditional) {
1878   Actions.CodeCompletePreprocessorDirective(InConditional);
1879 }
1880 
CodeCompleteInConditionalExclusion()1881 void Parser::CodeCompleteInConditionalExclusion() {
1882   Actions.CodeCompleteInPreprocessorConditionalExclusion(getCurScope());
1883 }
1884 
CodeCompleteMacroName(bool IsDefinition)1885 void Parser::CodeCompleteMacroName(bool IsDefinition) {
1886   Actions.CodeCompletePreprocessorMacroName(IsDefinition);
1887 }
1888 
CodeCompletePreprocessorExpression()1889 void Parser::CodeCompletePreprocessorExpression() {
1890   Actions.CodeCompletePreprocessorExpression();
1891 }
1892 
CodeCompleteMacroArgument(IdentifierInfo * Macro,MacroInfo * MacroInfo,unsigned ArgumentIndex)1893 void Parser::CodeCompleteMacroArgument(IdentifierInfo *Macro,
1894                                        MacroInfo *MacroInfo,
1895                                        unsigned ArgumentIndex) {
1896   Actions.CodeCompletePreprocessorMacroArgument(getCurScope(), Macro, MacroInfo,
1897                                                 ArgumentIndex);
1898 }
1899 
CodeCompleteNaturalLanguage()1900 void Parser::CodeCompleteNaturalLanguage() {
1901   Actions.CodeCompleteNaturalLanguage();
1902 }
1903 
ParseMicrosoftIfExistsCondition(IfExistsCondition & Result)1904 bool Parser::ParseMicrosoftIfExistsCondition(IfExistsCondition& Result) {
1905   assert((Tok.is(tok::kw___if_exists) || Tok.is(tok::kw___if_not_exists)) &&
1906          "Expected '__if_exists' or '__if_not_exists'");
1907   Result.IsIfExists = Tok.is(tok::kw___if_exists);
1908   Result.KeywordLoc = ConsumeToken();
1909 
1910   BalancedDelimiterTracker T(*this, tok::l_paren);
1911   if (T.consumeOpen()) {
1912     Diag(Tok, diag::err_expected_lparen_after)
1913       << (Result.IsIfExists? "__if_exists" : "__if_not_exists");
1914     return true;
1915   }
1916 
1917   // Parse nested-name-specifier.
1918   if (getLangOpts().CPlusPlus)
1919     ParseOptionalCXXScopeSpecifier(Result.SS, nullptr,
1920                                    /*EnteringContext=*/false);
1921 
1922   // Check nested-name specifier.
1923   if (Result.SS.isInvalid()) {
1924     T.skipToEnd();
1925     return true;
1926   }
1927 
1928   // Parse the unqualified-id.
1929   SourceLocation TemplateKWLoc; // FIXME: parsed, but unused.
1930   if (ParseUnqualifiedId(Result.SS, false, true, true, nullptr, TemplateKWLoc,
1931                          Result.Name)) {
1932     T.skipToEnd();
1933     return true;
1934   }
1935 
1936   if (T.consumeClose())
1937     return true;
1938 
1939   // Check if the symbol exists.
1940   switch (Actions.CheckMicrosoftIfExistsSymbol(getCurScope(), Result.KeywordLoc,
1941                                                Result.IsIfExists, Result.SS,
1942                                                Result.Name)) {
1943   case Sema::IER_Exists:
1944     Result.Behavior = Result.IsIfExists ? IEB_Parse : IEB_Skip;
1945     break;
1946 
1947   case Sema::IER_DoesNotExist:
1948     Result.Behavior = !Result.IsIfExists ? IEB_Parse : IEB_Skip;
1949     break;
1950 
1951   case Sema::IER_Dependent:
1952     Result.Behavior = IEB_Dependent;
1953     break;
1954 
1955   case Sema::IER_Error:
1956     return true;
1957   }
1958 
1959   return false;
1960 }
1961 
ParseMicrosoftIfExistsExternalDeclaration()1962 void Parser::ParseMicrosoftIfExistsExternalDeclaration() {
1963   IfExistsCondition Result;
1964   if (ParseMicrosoftIfExistsCondition(Result))
1965     return;
1966 
1967   BalancedDelimiterTracker Braces(*this, tok::l_brace);
1968   if (Braces.consumeOpen()) {
1969     Diag(Tok, diag::err_expected) << tok::l_brace;
1970     return;
1971   }
1972 
1973   switch (Result.Behavior) {
1974   case IEB_Parse:
1975     // Parse declarations below.
1976     break;
1977 
1978   case IEB_Dependent:
1979     llvm_unreachable("Cannot have a dependent external declaration");
1980 
1981   case IEB_Skip:
1982     Braces.skipToEnd();
1983     return;
1984   }
1985 
1986   // Parse the declarations.
1987   // FIXME: Support module import within __if_exists?
1988   while (Tok.isNot(tok::r_brace) && !isEofOrEom()) {
1989     ParsedAttributesWithRange attrs(AttrFactory);
1990     MaybeParseCXX11Attributes(attrs);
1991     MaybeParseMicrosoftAttributes(attrs);
1992     DeclGroupPtrTy Result = ParseExternalDeclaration(attrs);
1993     if (Result && !getCurScope()->getParent())
1994       Actions.getASTConsumer().HandleTopLevelDecl(Result.get());
1995   }
1996   Braces.consumeClose();
1997 }
1998 
ParseModuleImport(SourceLocation AtLoc)1999 Parser::DeclGroupPtrTy Parser::ParseModuleImport(SourceLocation AtLoc) {
2000   assert(Tok.isObjCAtKeyword(tok::objc_import) &&
2001          "Improper start to module import");
2002   SourceLocation ImportLoc = ConsumeToken();
2003 
2004   SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Path;
2005 
2006   // Parse the module path.
2007   do {
2008     if (!Tok.is(tok::identifier)) {
2009       if (Tok.is(tok::code_completion)) {
2010         Actions.CodeCompleteModuleImport(ImportLoc, Path);
2011         cutOffParsing();
2012         return nullptr;
2013       }
2014 
2015       Diag(Tok, diag::err_module_expected_ident);
2016       SkipUntil(tok::semi);
2017       return nullptr;
2018     }
2019 
2020     // Record this part of the module path.
2021     Path.push_back(std::make_pair(Tok.getIdentifierInfo(), Tok.getLocation()));
2022     ConsumeToken();
2023 
2024     if (Tok.is(tok::period)) {
2025       ConsumeToken();
2026       continue;
2027     }
2028 
2029     break;
2030   } while (true);
2031 
2032   if (PP.hadModuleLoaderFatalFailure()) {
2033     // With a fatal failure in the module loader, we abort parsing.
2034     cutOffParsing();
2035     return nullptr;
2036   }
2037 
2038   DeclResult Import = Actions.ActOnModuleImport(AtLoc, ImportLoc, Path);
2039   ExpectAndConsumeSemi(diag::err_module_expected_semi);
2040   if (Import.isInvalid())
2041     return nullptr;
2042 
2043   return Actions.ConvertDeclToDeclGroup(Import.get());
2044 }
2045 
2046 /// \brief Try recover parser when module annotation appears where it must not
2047 /// be found.
2048 /// \returns false if the recover was successful and parsing may be continued, or
2049 /// true if parser must bail out to top level and handle the token there.
parseMisplacedModuleImport()2050 bool Parser::parseMisplacedModuleImport() {
2051   while (true) {
2052     switch (Tok.getKind()) {
2053     case tok::annot_module_end:
2054       // Inform caller that recovery failed, the error must be handled at upper
2055       // level.
2056       return true;
2057     case tok::annot_module_begin:
2058       Actions.diagnoseMisplacedModuleImport(reinterpret_cast<Module *>(
2059         Tok.getAnnotationValue()), Tok.getLocation());
2060       return true;
2061     case tok::annot_module_include:
2062       // Module import found where it should not be, for instance, inside a
2063       // namespace. Recover by importing the module.
2064       Actions.ActOnModuleInclude(Tok.getLocation(),
2065                                  reinterpret_cast<Module *>(
2066                                  Tok.getAnnotationValue()));
2067       ConsumeToken();
2068       // If there is another module import, process it.
2069       continue;
2070     default:
2071       return false;
2072     }
2073   }
2074   return false;
2075 }
2076 
diagnoseOverflow()2077 bool BalancedDelimiterTracker::diagnoseOverflow() {
2078   P.Diag(P.Tok, diag::err_bracket_depth_exceeded)
2079     << P.getLangOpts().BracketDepth;
2080   P.Diag(P.Tok, diag::note_bracket_depth);
2081   P.cutOffParsing();
2082   return true;
2083 }
2084 
expectAndConsume(unsigned DiagID,const char * Msg,tok::TokenKind SkipToTok)2085 bool BalancedDelimiterTracker::expectAndConsume(unsigned DiagID,
2086                                                 const char *Msg,
2087                                                 tok::TokenKind SkipToTok) {
2088   LOpen = P.Tok.getLocation();
2089   if (P.ExpectAndConsume(Kind, DiagID, Msg)) {
2090     if (SkipToTok != tok::unknown)
2091       P.SkipUntil(SkipToTok, Parser::StopAtSemi);
2092     return true;
2093   }
2094 
2095   if (getDepth() < MaxDepth)
2096     return false;
2097 
2098   return diagnoseOverflow();
2099 }
2100 
diagnoseMissingClose()2101 bool BalancedDelimiterTracker::diagnoseMissingClose() {
2102   assert(!P.Tok.is(Close) && "Should have consumed closing delimiter");
2103 
2104   if (P.Tok.is(tok::annot_module_end))
2105     P.Diag(P.Tok, diag::err_missing_before_module_end) << Close;
2106   else
2107     P.Diag(P.Tok, diag::err_expected) << Close;
2108   P.Diag(LOpen, diag::note_matching) << Kind;
2109 
2110   // If we're not already at some kind of closing bracket, skip to our closing
2111   // token.
2112   if (P.Tok.isNot(tok::r_paren) && P.Tok.isNot(tok::r_brace) &&
2113       P.Tok.isNot(tok::r_square) &&
2114       P.SkipUntil(Close, FinalToken,
2115                   Parser::StopAtSemi | Parser::StopBeforeMatch) &&
2116       P.Tok.is(Close))
2117     LClose = P.ConsumeAnyToken();
2118   return true;
2119 }
2120 
skipToEnd()2121 void BalancedDelimiterTracker::skipToEnd() {
2122   P.SkipUntil(Close, Parser::StopBeforeMatch);
2123   consumeClose();
2124 }
2125