1 //===--- ParseExpr.cpp - Expression Parsing -------------------------------===//
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 /// \file
11 /// \brief Provides the Expression parsing implementation.
12 ///
13 /// Expressions in C99 basically consist of a bunch of binary operators with
14 /// unary operators and other random stuff at the leaves.
15 ///
16 /// In the C99 grammar, these unary operators bind tightest and are represented
17 /// as the 'cast-expression' production. Everything else is either a binary
18 /// operator (e.g. '/') or a ternary operator ("?:"). The unary leaves are
19 /// handled by ParseCastExpression, the higher level pieces are handled by
20 /// ParseBinaryExpression.
21 ///
22 //===----------------------------------------------------------------------===//
23
24 #include "clang/Parse/Parser.h"
25 #include "clang/Sema/DeclSpec.h"
26 #include "clang/Sema/Scope.h"
27 #include "clang/Sema/ParsedTemplate.h"
28 #include "clang/Sema/TypoCorrection.h"
29 #include "clang/Basic/PrettyStackTrace.h"
30 #include "RAIIObjectsForParser.h"
31 #include "llvm/ADT/SmallVector.h"
32 #include "llvm/ADT/SmallString.h"
33 using namespace clang;
34
35 /// \brief Return the precedence of the specified binary operator token.
getBinOpPrecedence(tok::TokenKind Kind,bool GreaterThanIsOperator,bool CPlusPlus0x)36 static prec::Level getBinOpPrecedence(tok::TokenKind Kind,
37 bool GreaterThanIsOperator,
38 bool CPlusPlus0x) {
39 switch (Kind) {
40 case tok::greater:
41 // C++ [temp.names]p3:
42 // [...] When parsing a template-argument-list, the first
43 // non-nested > is taken as the ending delimiter rather than a
44 // greater-than operator. [...]
45 if (GreaterThanIsOperator)
46 return prec::Relational;
47 return prec::Unknown;
48
49 case tok::greatergreater:
50 // C++0x [temp.names]p3:
51 //
52 // [...] Similarly, the first non-nested >> is treated as two
53 // consecutive but distinct > tokens, the first of which is
54 // taken as the end of the template-argument-list and completes
55 // the template-id. [...]
56 if (GreaterThanIsOperator || !CPlusPlus0x)
57 return prec::Shift;
58 return prec::Unknown;
59
60 default: return prec::Unknown;
61 case tok::comma: return prec::Comma;
62 case tok::equal:
63 case tok::starequal:
64 case tok::slashequal:
65 case tok::percentequal:
66 case tok::plusequal:
67 case tok::minusequal:
68 case tok::lesslessequal:
69 case tok::greatergreaterequal:
70 case tok::ampequal:
71 case tok::caretequal:
72 case tok::pipeequal: return prec::Assignment;
73 case tok::question: return prec::Conditional;
74 case tok::pipepipe: return prec::LogicalOr;
75 case tok::ampamp: return prec::LogicalAnd;
76 case tok::pipe: return prec::InclusiveOr;
77 case tok::caret: return prec::ExclusiveOr;
78 case tok::amp: return prec::And;
79 case tok::exclaimequal:
80 case tok::equalequal: return prec::Equality;
81 case tok::lessequal:
82 case tok::less:
83 case tok::greaterequal: return prec::Relational;
84 case tok::lessless: return prec::Shift;
85 case tok::plus:
86 case tok::minus: return prec::Additive;
87 case tok::percent:
88 case tok::slash:
89 case tok::star: return prec::Multiplicative;
90 case tok::periodstar:
91 case tok::arrowstar: return prec::PointerToMember;
92 }
93 }
94
95
96 /// \brief Simple precedence-based parser for binary/ternary operators.
97 ///
98 /// Note: we diverge from the C99 grammar when parsing the assignment-expression
99 /// production. C99 specifies that the LHS of an assignment operator should be
100 /// parsed as a unary-expression, but consistency dictates that it be a
101 /// conditional-expession. In practice, the important thing here is that the
102 /// LHS of an assignment has to be an l-value, which productions between
103 /// unary-expression and conditional-expression don't produce. Because we want
104 /// consistency, we parse the LHS as a conditional-expression, then check for
105 /// l-value-ness in semantic analysis stages.
106 ///
107 /// \verbatim
108 /// pm-expression: [C++ 5.5]
109 /// cast-expression
110 /// pm-expression '.*' cast-expression
111 /// pm-expression '->*' cast-expression
112 ///
113 /// multiplicative-expression: [C99 6.5.5]
114 /// Note: in C++, apply pm-expression instead of cast-expression
115 /// cast-expression
116 /// multiplicative-expression '*' cast-expression
117 /// multiplicative-expression '/' cast-expression
118 /// multiplicative-expression '%' cast-expression
119 ///
120 /// additive-expression: [C99 6.5.6]
121 /// multiplicative-expression
122 /// additive-expression '+' multiplicative-expression
123 /// additive-expression '-' multiplicative-expression
124 ///
125 /// shift-expression: [C99 6.5.7]
126 /// additive-expression
127 /// shift-expression '<<' additive-expression
128 /// shift-expression '>>' additive-expression
129 ///
130 /// relational-expression: [C99 6.5.8]
131 /// shift-expression
132 /// relational-expression '<' shift-expression
133 /// relational-expression '>' shift-expression
134 /// relational-expression '<=' shift-expression
135 /// relational-expression '>=' shift-expression
136 ///
137 /// equality-expression: [C99 6.5.9]
138 /// relational-expression
139 /// equality-expression '==' relational-expression
140 /// equality-expression '!=' relational-expression
141 ///
142 /// AND-expression: [C99 6.5.10]
143 /// equality-expression
144 /// AND-expression '&' equality-expression
145 ///
146 /// exclusive-OR-expression: [C99 6.5.11]
147 /// AND-expression
148 /// exclusive-OR-expression '^' AND-expression
149 ///
150 /// inclusive-OR-expression: [C99 6.5.12]
151 /// exclusive-OR-expression
152 /// inclusive-OR-expression '|' exclusive-OR-expression
153 ///
154 /// logical-AND-expression: [C99 6.5.13]
155 /// inclusive-OR-expression
156 /// logical-AND-expression '&&' inclusive-OR-expression
157 ///
158 /// logical-OR-expression: [C99 6.5.14]
159 /// logical-AND-expression
160 /// logical-OR-expression '||' logical-AND-expression
161 ///
162 /// conditional-expression: [C99 6.5.15]
163 /// logical-OR-expression
164 /// logical-OR-expression '?' expression ':' conditional-expression
165 /// [GNU] logical-OR-expression '?' ':' conditional-expression
166 /// [C++] the third operand is an assignment-expression
167 ///
168 /// assignment-expression: [C99 6.5.16]
169 /// conditional-expression
170 /// unary-expression assignment-operator assignment-expression
171 /// [C++] throw-expression [C++ 15]
172 ///
173 /// assignment-operator: one of
174 /// = *= /= %= += -= <<= >>= &= ^= |=
175 ///
176 /// expression: [C99 6.5.17]
177 /// assignment-expression ...[opt]
178 /// expression ',' assignment-expression ...[opt]
179 /// \endverbatim
ParseExpression(TypeCastState isTypeCast)180 ExprResult Parser::ParseExpression(TypeCastState isTypeCast) {
181 ExprResult LHS(ParseAssignmentExpression(isTypeCast));
182 return ParseRHSOfBinaryExpression(LHS, prec::Comma);
183 }
184
185 /// This routine is called when the '@' is seen and consumed.
186 /// Current token is an Identifier and is not a 'try'. This
187 /// routine is necessary to disambiguate \@try-statement from,
188 /// for example, \@encode-expression.
189 ///
190 ExprResult
ParseExpressionWithLeadingAt(SourceLocation AtLoc)191 Parser::ParseExpressionWithLeadingAt(SourceLocation AtLoc) {
192 ExprResult LHS(ParseObjCAtExpression(AtLoc));
193 return ParseRHSOfBinaryExpression(LHS, prec::Comma);
194 }
195
196 /// This routine is called when a leading '__extension__' is seen and
197 /// consumed. This is necessary because the token gets consumed in the
198 /// process of disambiguating between an expression and a declaration.
199 ExprResult
ParseExpressionWithLeadingExtension(SourceLocation ExtLoc)200 Parser::ParseExpressionWithLeadingExtension(SourceLocation ExtLoc) {
201 ExprResult LHS(true);
202 {
203 // Silence extension warnings in the sub-expression
204 ExtensionRAIIObject O(Diags);
205
206 LHS = ParseCastExpression(false);
207 }
208
209 if (!LHS.isInvalid())
210 LHS = Actions.ActOnUnaryOp(getCurScope(), ExtLoc, tok::kw___extension__,
211 LHS.take());
212
213 return ParseRHSOfBinaryExpression(LHS, prec::Comma);
214 }
215
216 /// \brief Parse an expr that doesn't include (top-level) commas.
ParseAssignmentExpression(TypeCastState isTypeCast)217 ExprResult Parser::ParseAssignmentExpression(TypeCastState isTypeCast) {
218 if (Tok.is(tok::code_completion)) {
219 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Expression);
220 cutOffParsing();
221 return ExprError();
222 }
223
224 if (Tok.is(tok::kw_throw))
225 return ParseThrowExpression();
226
227 ExprResult LHS = ParseCastExpression(/*isUnaryExpression=*/false,
228 /*isAddressOfOperand=*/false,
229 isTypeCast);
230 return ParseRHSOfBinaryExpression(LHS, prec::Assignment);
231 }
232
233 /// \brief Parse an assignment expression where part of an Objective-C message
234 /// send has already been parsed.
235 ///
236 /// In this case \p LBracLoc indicates the location of the '[' of the message
237 /// send, and either \p ReceiverName or \p ReceiverExpr is non-null indicating
238 /// the receiver of the message.
239 ///
240 /// Since this handles full assignment-expression's, it handles postfix
241 /// expressions and other binary operators for these expressions as well.
242 ExprResult
ParseAssignmentExprWithObjCMessageExprStart(SourceLocation LBracLoc,SourceLocation SuperLoc,ParsedType ReceiverType,Expr * ReceiverExpr)243 Parser::ParseAssignmentExprWithObjCMessageExprStart(SourceLocation LBracLoc,
244 SourceLocation SuperLoc,
245 ParsedType ReceiverType,
246 Expr *ReceiverExpr) {
247 ExprResult R
248 = ParseObjCMessageExpressionBody(LBracLoc, SuperLoc,
249 ReceiverType, ReceiverExpr);
250 R = ParsePostfixExpressionSuffix(R);
251 return ParseRHSOfBinaryExpression(R, prec::Assignment);
252 }
253
254
ParseConstantExpression(TypeCastState isTypeCast)255 ExprResult Parser::ParseConstantExpression(TypeCastState isTypeCast) {
256 // C++03 [basic.def.odr]p2:
257 // An expression is potentially evaluated unless it appears where an
258 // integral constant expression is required (see 5.19) [...].
259 // C++98 and C++11 have no such rule, but this is only a defect in C++98.
260 EnterExpressionEvaluationContext Unevaluated(Actions,
261 Sema::ConstantEvaluated);
262
263 ExprResult LHS(ParseCastExpression(false, false, isTypeCast));
264 ExprResult Res(ParseRHSOfBinaryExpression(LHS, prec::Conditional));
265 return Actions.ActOnConstantExpression(Res);
266 }
267
268 /// \brief Parse a binary expression that starts with \p LHS and has a
269 /// precedence of at least \p MinPrec.
270 ExprResult
ParseRHSOfBinaryExpression(ExprResult LHS,prec::Level MinPrec)271 Parser::ParseRHSOfBinaryExpression(ExprResult LHS, prec::Level MinPrec) {
272 prec::Level NextTokPrec = getBinOpPrecedence(Tok.getKind(),
273 GreaterThanIsOperator,
274 getLangOpts().CPlusPlus0x);
275 SourceLocation ColonLoc;
276
277 while (1) {
278 // If this token has a lower precedence than we are allowed to parse (e.g.
279 // because we are called recursively, or because the token is not a binop),
280 // then we are done!
281 if (NextTokPrec < MinPrec)
282 return LHS;
283
284 // Consume the operator, saving the operator token for error reporting.
285 Token OpToken = Tok;
286 ConsumeToken();
287
288 // Special case handling for the ternary operator.
289 ExprResult TernaryMiddle(true);
290 if (NextTokPrec == prec::Conditional) {
291 if (Tok.isNot(tok::colon)) {
292 // Don't parse FOO:BAR as if it were a typo for FOO::BAR.
293 ColonProtectionRAIIObject X(*this);
294
295 // Handle this production specially:
296 // logical-OR-expression '?' expression ':' conditional-expression
297 // In particular, the RHS of the '?' is 'expression', not
298 // 'logical-OR-expression' as we might expect.
299 TernaryMiddle = ParseExpression();
300 if (TernaryMiddle.isInvalid()) {
301 LHS = ExprError();
302 TernaryMiddle = 0;
303 }
304 } else {
305 // Special case handling of "X ? Y : Z" where Y is empty:
306 // logical-OR-expression '?' ':' conditional-expression [GNU]
307 TernaryMiddle = 0;
308 Diag(Tok, diag::ext_gnu_conditional_expr);
309 }
310
311 if (Tok.is(tok::colon)) {
312 // Eat the colon.
313 ColonLoc = ConsumeToken();
314 } else {
315 // Otherwise, we're missing a ':'. Assume that this was a typo that
316 // the user forgot. If we're not in a macro expansion, we can suggest
317 // a fixit hint. If there were two spaces before the current token,
318 // suggest inserting the colon in between them, otherwise insert ": ".
319 SourceLocation FILoc = Tok.getLocation();
320 const char *FIText = ": ";
321 const SourceManager &SM = PP.getSourceManager();
322 if (FILoc.isFileID() || PP.isAtStartOfMacroExpansion(FILoc, &FILoc)) {
323 assert(FILoc.isFileID());
324 bool IsInvalid = false;
325 const char *SourcePtr =
326 SM.getCharacterData(FILoc.getLocWithOffset(-1), &IsInvalid);
327 if (!IsInvalid && *SourcePtr == ' ') {
328 SourcePtr =
329 SM.getCharacterData(FILoc.getLocWithOffset(-2), &IsInvalid);
330 if (!IsInvalid && *SourcePtr == ' ') {
331 FILoc = FILoc.getLocWithOffset(-1);
332 FIText = ":";
333 }
334 }
335 }
336
337 Diag(Tok, diag::err_expected_colon)
338 << FixItHint::CreateInsertion(FILoc, FIText);
339 Diag(OpToken, diag::note_matching) << "?";
340 ColonLoc = Tok.getLocation();
341 }
342 }
343
344 // Code completion for the right-hand side of an assignment expression
345 // goes through a special hook that takes the left-hand side into account.
346 if (Tok.is(tok::code_completion) && NextTokPrec == prec::Assignment) {
347 Actions.CodeCompleteAssignmentRHS(getCurScope(), LHS.get());
348 cutOffParsing();
349 return ExprError();
350 }
351
352 // Parse another leaf here for the RHS of the operator.
353 // ParseCastExpression works here because all RHS expressions in C have it
354 // as a prefix, at least. However, in C++, an assignment-expression could
355 // be a throw-expression, which is not a valid cast-expression.
356 // Therefore we need some special-casing here.
357 // Also note that the third operand of the conditional operator is
358 // an assignment-expression in C++, and in C++11, we can have a
359 // braced-init-list on the RHS of an assignment. For better diagnostics,
360 // parse as if we were allowed braced-init-lists everywhere, and check that
361 // they only appear on the RHS of assignments later.
362 ExprResult RHS;
363 bool RHSIsInitList = false;
364 if (getLangOpts().CPlusPlus0x && Tok.is(tok::l_brace)) {
365 RHS = ParseBraceInitializer();
366 RHSIsInitList = true;
367 } else if (getLangOpts().CPlusPlus && NextTokPrec <= prec::Conditional)
368 RHS = ParseAssignmentExpression();
369 else
370 RHS = ParseCastExpression(false);
371
372 if (RHS.isInvalid())
373 LHS = ExprError();
374
375 // Remember the precedence of this operator and get the precedence of the
376 // operator immediately to the right of the RHS.
377 prec::Level ThisPrec = NextTokPrec;
378 NextTokPrec = getBinOpPrecedence(Tok.getKind(), GreaterThanIsOperator,
379 getLangOpts().CPlusPlus0x);
380
381 // Assignment and conditional expressions are right-associative.
382 bool isRightAssoc = ThisPrec == prec::Conditional ||
383 ThisPrec == prec::Assignment;
384
385 // Get the precedence of the operator to the right of the RHS. If it binds
386 // more tightly with RHS than we do, evaluate it completely first.
387 if (ThisPrec < NextTokPrec ||
388 (ThisPrec == NextTokPrec && isRightAssoc)) {
389 if (!RHS.isInvalid() && RHSIsInitList) {
390 Diag(Tok, diag::err_init_list_bin_op)
391 << /*LHS*/0 << PP.getSpelling(Tok) << Actions.getExprRange(RHS.get());
392 RHS = ExprError();
393 }
394 // If this is left-associative, only parse things on the RHS that bind
395 // more tightly than the current operator. If it is left-associative, it
396 // is okay, to bind exactly as tightly. For example, compile A=B=C=D as
397 // A=(B=(C=D)), where each paren is a level of recursion here.
398 // The function takes ownership of the RHS.
399 RHS = ParseRHSOfBinaryExpression(RHS,
400 static_cast<prec::Level>(ThisPrec + !isRightAssoc));
401 RHSIsInitList = false;
402
403 if (RHS.isInvalid())
404 LHS = ExprError();
405
406 NextTokPrec = getBinOpPrecedence(Tok.getKind(), GreaterThanIsOperator,
407 getLangOpts().CPlusPlus0x);
408 }
409 assert(NextTokPrec <= ThisPrec && "Recursion didn't work!");
410
411 if (!RHS.isInvalid() && RHSIsInitList) {
412 if (ThisPrec == prec::Assignment) {
413 Diag(OpToken, diag::warn_cxx98_compat_generalized_initializer_lists)
414 << Actions.getExprRange(RHS.get());
415 } else {
416 Diag(OpToken, diag::err_init_list_bin_op)
417 << /*RHS*/1 << PP.getSpelling(OpToken)
418 << Actions.getExprRange(RHS.get());
419 LHS = ExprError();
420 }
421 }
422
423 if (!LHS.isInvalid()) {
424 // Combine the LHS and RHS into the LHS (e.g. build AST).
425 if (TernaryMiddle.isInvalid()) {
426 // If we're using '>>' as an operator within a template
427 // argument list (in C++98), suggest the addition of
428 // parentheses so that the code remains well-formed in C++0x.
429 if (!GreaterThanIsOperator && OpToken.is(tok::greatergreater))
430 SuggestParentheses(OpToken.getLocation(),
431 diag::warn_cxx0x_right_shift_in_template_arg,
432 SourceRange(Actions.getExprRange(LHS.get()).getBegin(),
433 Actions.getExprRange(RHS.get()).getEnd()));
434
435 LHS = Actions.ActOnBinOp(getCurScope(), OpToken.getLocation(),
436 OpToken.getKind(), LHS.take(), RHS.take());
437 } else
438 LHS = Actions.ActOnConditionalOp(OpToken.getLocation(), ColonLoc,
439 LHS.take(), TernaryMiddle.take(),
440 RHS.take());
441 }
442 }
443 }
444
445 /// \brief Parse a cast-expression, or, if \p isUnaryExpression is true,
446 /// parse a unary-expression.
447 ///
448 /// \p isAddressOfOperand exists because an id-expression that is the
449 /// operand of address-of gets special treatment due to member pointers.
450 ///
ParseCastExpression(bool isUnaryExpression,bool isAddressOfOperand,TypeCastState isTypeCast)451 ExprResult Parser::ParseCastExpression(bool isUnaryExpression,
452 bool isAddressOfOperand,
453 TypeCastState isTypeCast) {
454 bool NotCastExpr;
455 ExprResult Res = ParseCastExpression(isUnaryExpression,
456 isAddressOfOperand,
457 NotCastExpr,
458 isTypeCast);
459 if (NotCastExpr)
460 Diag(Tok, diag::err_expected_expression);
461 return Res;
462 }
463
464 namespace {
465 class CastExpressionIdValidator : public CorrectionCandidateCallback {
466 public:
CastExpressionIdValidator(bool AllowTypes,bool AllowNonTypes)467 CastExpressionIdValidator(bool AllowTypes, bool AllowNonTypes)
468 : AllowNonTypes(AllowNonTypes) {
469 WantTypeSpecifiers = AllowTypes;
470 }
471
ValidateCandidate(const TypoCorrection & candidate)472 virtual bool ValidateCandidate(const TypoCorrection &candidate) {
473 NamedDecl *ND = candidate.getCorrectionDecl();
474 if (!ND)
475 return candidate.isKeyword();
476
477 if (isa<TypeDecl>(ND))
478 return WantTypeSpecifiers;
479 return AllowNonTypes;
480 }
481
482 private:
483 bool AllowNonTypes;
484 };
485 }
486
487 /// \brief Parse a cast-expression, or, if \pisUnaryExpression is true, parse
488 /// a unary-expression.
489 ///
490 /// \p isAddressOfOperand exists because an id-expression that is the operand
491 /// of address-of gets special treatment due to member pointers. NotCastExpr
492 /// is set to true if the token is not the start of a cast-expression, and no
493 /// diagnostic is emitted in this case.
494 ///
495 /// \verbatim
496 /// cast-expression: [C99 6.5.4]
497 /// unary-expression
498 /// '(' type-name ')' cast-expression
499 ///
500 /// unary-expression: [C99 6.5.3]
501 /// postfix-expression
502 /// '++' unary-expression
503 /// '--' unary-expression
504 /// unary-operator cast-expression
505 /// 'sizeof' unary-expression
506 /// 'sizeof' '(' type-name ')'
507 /// [C++11] 'sizeof' '...' '(' identifier ')'
508 /// [GNU] '__alignof' unary-expression
509 /// [GNU] '__alignof' '(' type-name ')'
510 /// [C11] '_Alignof' '(' type-name ')'
511 /// [C++11] 'alignof' '(' type-id ')'
512 /// [GNU] '&&' identifier
513 /// [C++11] 'noexcept' '(' expression ')' [C++11 5.3.7]
514 /// [C++] new-expression
515 /// [C++] delete-expression
516 ///
517 /// unary-operator: one of
518 /// '&' '*' '+' '-' '~' '!'
519 /// [GNU] '__extension__' '__real' '__imag'
520 ///
521 /// primary-expression: [C99 6.5.1]
522 /// [C99] identifier
523 /// [C++] id-expression
524 /// constant
525 /// string-literal
526 /// [C++] boolean-literal [C++ 2.13.5]
527 /// [C++11] 'nullptr' [C++11 2.14.7]
528 /// [C++11] user-defined-literal
529 /// '(' expression ')'
530 /// [C11] generic-selection
531 /// '__func__' [C99 6.4.2.2]
532 /// [GNU] '__FUNCTION__'
533 /// [GNU] '__PRETTY_FUNCTION__'
534 /// [GNU] '(' compound-statement ')'
535 /// [GNU] '__builtin_va_arg' '(' assignment-expression ',' type-name ')'
536 /// [GNU] '__builtin_offsetof' '(' type-name ',' offsetof-member-designator')'
537 /// [GNU] '__builtin_choose_expr' '(' assign-expr ',' assign-expr ','
538 /// assign-expr ')'
539 /// [GNU] '__builtin_types_compatible_p' '(' type-name ',' type-name ')'
540 /// [GNU] '__null'
541 /// [OBJC] '[' objc-message-expr ']'
542 /// [OBJC] '\@selector' '(' objc-selector-arg ')'
543 /// [OBJC] '\@protocol' '(' identifier ')'
544 /// [OBJC] '\@encode' '(' type-name ')'
545 /// [OBJC] objc-string-literal
546 /// [C++] simple-type-specifier '(' expression-list[opt] ')' [C++ 5.2.3]
547 /// [C++11] simple-type-specifier braced-init-list [C++11 5.2.3]
548 /// [C++] typename-specifier '(' expression-list[opt] ')' [C++ 5.2.3]
549 /// [C++11] typename-specifier braced-init-list [C++11 5.2.3]
550 /// [C++] 'const_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1]
551 /// [C++] 'dynamic_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1]
552 /// [C++] 'reinterpret_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1]
553 /// [C++] 'static_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1]
554 /// [C++] 'typeid' '(' expression ')' [C++ 5.2p1]
555 /// [C++] 'typeid' '(' type-id ')' [C++ 5.2p1]
556 /// [C++] 'this' [C++ 9.3.2]
557 /// [G++] unary-type-trait '(' type-id ')'
558 /// [G++] binary-type-trait '(' type-id ',' type-id ')' [TODO]
559 /// [EMBT] array-type-trait '(' type-id ',' integer ')'
560 /// [clang] '^' block-literal
561 ///
562 /// constant: [C99 6.4.4]
563 /// integer-constant
564 /// floating-constant
565 /// enumeration-constant -> identifier
566 /// character-constant
567 ///
568 /// id-expression: [C++ 5.1]
569 /// unqualified-id
570 /// qualified-id
571 ///
572 /// unqualified-id: [C++ 5.1]
573 /// identifier
574 /// operator-function-id
575 /// conversion-function-id
576 /// '~' class-name
577 /// template-id
578 ///
579 /// new-expression: [C++ 5.3.4]
580 /// '::'[opt] 'new' new-placement[opt] new-type-id
581 /// new-initializer[opt]
582 /// '::'[opt] 'new' new-placement[opt] '(' type-id ')'
583 /// new-initializer[opt]
584 ///
585 /// delete-expression: [C++ 5.3.5]
586 /// '::'[opt] 'delete' cast-expression
587 /// '::'[opt] 'delete' '[' ']' cast-expression
588 ///
589 /// [GNU/Embarcadero] unary-type-trait:
590 /// '__is_arithmetic'
591 /// '__is_floating_point'
592 /// '__is_integral'
593 /// '__is_lvalue_expr'
594 /// '__is_rvalue_expr'
595 /// '__is_complete_type'
596 /// '__is_void'
597 /// '__is_array'
598 /// '__is_function'
599 /// '__is_reference'
600 /// '__is_lvalue_reference'
601 /// '__is_rvalue_reference'
602 /// '__is_fundamental'
603 /// '__is_object'
604 /// '__is_scalar'
605 /// '__is_compound'
606 /// '__is_pointer'
607 /// '__is_member_object_pointer'
608 /// '__is_member_function_pointer'
609 /// '__is_member_pointer'
610 /// '__is_const'
611 /// '__is_volatile'
612 /// '__is_trivial'
613 /// '__is_standard_layout'
614 /// '__is_signed'
615 /// '__is_unsigned'
616 ///
617 /// [GNU] unary-type-trait:
618 /// '__has_nothrow_assign'
619 /// '__has_nothrow_copy'
620 /// '__has_nothrow_constructor'
621 /// '__has_trivial_assign' [TODO]
622 /// '__has_trivial_copy' [TODO]
623 /// '__has_trivial_constructor'
624 /// '__has_trivial_destructor'
625 /// '__has_virtual_destructor'
626 /// '__is_abstract' [TODO]
627 /// '__is_class'
628 /// '__is_empty' [TODO]
629 /// '__is_enum'
630 /// '__is_final'
631 /// '__is_pod'
632 /// '__is_polymorphic'
633 /// '__is_trivial'
634 /// '__is_union'
635 ///
636 /// [Clang] unary-type-trait:
637 /// '__trivially_copyable'
638 ///
639 /// binary-type-trait:
640 /// [GNU] '__is_base_of'
641 /// [MS] '__is_convertible_to'
642 /// '__is_convertible'
643 /// '__is_same'
644 ///
645 /// [Embarcadero] array-type-trait:
646 /// '__array_rank'
647 /// '__array_extent'
648 ///
649 /// [Embarcadero] expression-trait:
650 /// '__is_lvalue_expr'
651 /// '__is_rvalue_expr'
652 /// \endverbatim
653 ///
ParseCastExpression(bool isUnaryExpression,bool isAddressOfOperand,bool & NotCastExpr,TypeCastState isTypeCast)654 ExprResult Parser::ParseCastExpression(bool isUnaryExpression,
655 bool isAddressOfOperand,
656 bool &NotCastExpr,
657 TypeCastState isTypeCast) {
658 ExprResult Res;
659 tok::TokenKind SavedKind = Tok.getKind();
660 NotCastExpr = false;
661
662 // This handles all of cast-expression, unary-expression, postfix-expression,
663 // and primary-expression. We handle them together like this for efficiency
664 // and to simplify handling of an expression starting with a '(' token: which
665 // may be one of a parenthesized expression, cast-expression, compound literal
666 // expression, or statement expression.
667 //
668 // If the parsed tokens consist of a primary-expression, the cases below
669 // break out of the switch; at the end we call ParsePostfixExpressionSuffix
670 // to handle the postfix expression suffixes. Cases that cannot be followed
671 // by postfix exprs should return without invoking
672 // ParsePostfixExpressionSuffix.
673 switch (SavedKind) {
674 case tok::l_paren: {
675 // If this expression is limited to being a unary-expression, the parent can
676 // not start a cast expression.
677 ParenParseOption ParenExprType =
678 (isUnaryExpression && !getLangOpts().CPlusPlus)? CompoundLiteral : CastExpr;
679 ParsedType CastTy;
680 SourceLocation RParenLoc;
681
682 {
683 // The inside of the parens don't need to be a colon protected scope, and
684 // isn't immediately a message send.
685 ColonProtectionRAIIObject X(*this, false);
686
687 Res = ParseParenExpression(ParenExprType, false/*stopIfCastExr*/,
688 isTypeCast == IsTypeCast, CastTy, RParenLoc);
689 }
690
691 switch (ParenExprType) {
692 case SimpleExpr: break; // Nothing else to do.
693 case CompoundStmt: break; // Nothing else to do.
694 case CompoundLiteral:
695 // We parsed '(' type-name ')' '{' ... '}'. If any suffixes of
696 // postfix-expression exist, parse them now.
697 break;
698 case CastExpr:
699 // We have parsed the cast-expression and no postfix-expr pieces are
700 // following.
701 return Res;
702 }
703
704 break;
705 }
706
707 // primary-expression
708 case tok::numeric_constant:
709 // constant: integer-constant
710 // constant: floating-constant
711
712 Res = Actions.ActOnNumericConstant(Tok, /*UDLScope*/getCurScope());
713 ConsumeToken();
714 break;
715
716 case tok::kw_true:
717 case tok::kw_false:
718 return ParseCXXBoolLiteral();
719
720 case tok::kw___objc_yes:
721 case tok::kw___objc_no:
722 return ParseObjCBoolLiteral();
723
724 case tok::kw_nullptr:
725 Diag(Tok, diag::warn_cxx98_compat_nullptr);
726 return Actions.ActOnCXXNullPtrLiteral(ConsumeToken());
727
728 case tok::annot_primary_expr:
729 assert(Res.get() == 0 && "Stray primary-expression annotation?");
730 Res = getExprAnnotation(Tok);
731 ConsumeToken();
732 break;
733
734 case tok::kw_decltype:
735 case tok::identifier: { // primary-expression: identifier
736 // unqualified-id: identifier
737 // constant: enumeration-constant
738 // Turn a potentially qualified name into a annot_typename or
739 // annot_cxxscope if it would be valid. This handles things like x::y, etc.
740 if (getLangOpts().CPlusPlus) {
741 // Avoid the unnecessary parse-time lookup in the common case
742 // where the syntax forbids a type.
743 const Token &Next = NextToken();
744
745 // If this identifier was reverted from a token ID, and the next token
746 // is a parenthesis, this is likely to be a use of a type trait. Check
747 // those tokens.
748 if (Next.is(tok::l_paren) &&
749 Tok.is(tok::identifier) &&
750 Tok.getIdentifierInfo()->hasRevertedTokenIDToIdentifier()) {
751 IdentifierInfo *II = Tok.getIdentifierInfo();
752 // Build up the mapping of revertable type traits, for future use.
753 if (RevertableTypeTraits.empty()) {
754 #define RTT_JOIN2(X) X
755 #define RTT_JOIN(X,Y) X##Y
756 #define REVERTABLE_TYPE_TRAIT(Name) \
757 RevertableTypeTraits[PP.getIdentifierInfo(#Name)] \
758 = RTT_JOIN(tok::kw_,Name)
759
760 REVERTABLE_TYPE_TRAIT(__is_arithmetic);
761 REVERTABLE_TYPE_TRAIT(__is_convertible);
762 REVERTABLE_TYPE_TRAIT(__is_empty);
763 REVERTABLE_TYPE_TRAIT(__is_floating_point);
764 REVERTABLE_TYPE_TRAIT(__is_function);
765 REVERTABLE_TYPE_TRAIT(__is_fundamental);
766 REVERTABLE_TYPE_TRAIT(__is_integral);
767 REVERTABLE_TYPE_TRAIT(__is_member_function_pointer);
768 REVERTABLE_TYPE_TRAIT(__is_member_pointer);
769 REVERTABLE_TYPE_TRAIT(__is_pod);
770 REVERTABLE_TYPE_TRAIT(__is_pointer);
771 REVERTABLE_TYPE_TRAIT(__is_same);
772 REVERTABLE_TYPE_TRAIT(__is_scalar);
773 REVERTABLE_TYPE_TRAIT(__is_signed);
774 REVERTABLE_TYPE_TRAIT(__is_unsigned);
775 REVERTABLE_TYPE_TRAIT(__is_void);
776 #undef REVERTABLE_TYPE_TRAIT
777 #undef RTT_JOIN2
778 #undef RTT_JOIN
779 }
780
781 // If we find that this is in fact the name of a type trait,
782 // update the token kind in place and parse again to treat it as
783 // the appropriate kind of type trait.
784 llvm::SmallDenseMap<IdentifierInfo *, tok::TokenKind>::iterator Known
785 = RevertableTypeTraits.find(II);
786 if (Known != RevertableTypeTraits.end()) {
787 Tok.setKind(Known->second);
788 return ParseCastExpression(isUnaryExpression, isAddressOfOperand,
789 NotCastExpr, isTypeCast);
790 }
791 }
792
793 if (Next.is(tok::coloncolon) ||
794 (!ColonIsSacred && Next.is(tok::colon)) ||
795 Next.is(tok::less) ||
796 Next.is(tok::l_paren) ||
797 Next.is(tok::l_brace)) {
798 // If TryAnnotateTypeOrScopeToken annotates the token, tail recurse.
799 if (TryAnnotateTypeOrScopeToken())
800 return ExprError();
801 if (!Tok.is(tok::identifier))
802 return ParseCastExpression(isUnaryExpression, isAddressOfOperand);
803 }
804 }
805
806 // Consume the identifier so that we can see if it is followed by a '(' or
807 // '.'.
808 IdentifierInfo &II = *Tok.getIdentifierInfo();
809 SourceLocation ILoc = ConsumeToken();
810
811 // Support 'Class.property' and 'super.property' notation.
812 if (getLangOpts().ObjC1 && Tok.is(tok::period) &&
813 (Actions.getTypeName(II, ILoc, getCurScope()) ||
814 // Allow the base to be 'super' if in an objc-method.
815 (&II == Ident_super && getCurScope()->isInObjcMethodScope()))) {
816 ConsumeToken();
817
818 // Allow either an identifier or the keyword 'class' (in C++).
819 if (Tok.isNot(tok::identifier) &&
820 !(getLangOpts().CPlusPlus && Tok.is(tok::kw_class))) {
821 Diag(Tok, diag::err_expected_property_name);
822 return ExprError();
823 }
824 IdentifierInfo &PropertyName = *Tok.getIdentifierInfo();
825 SourceLocation PropertyLoc = ConsumeToken();
826
827 Res = Actions.ActOnClassPropertyRefExpr(II, PropertyName,
828 ILoc, PropertyLoc);
829 break;
830 }
831
832 // In an Objective-C method, if we have "super" followed by an identifier,
833 // the token sequence is ill-formed. However, if there's a ':' or ']' after
834 // that identifier, this is probably a message send with a missing open
835 // bracket. Treat it as such.
836 if (getLangOpts().ObjC1 && &II == Ident_super && !InMessageExpression &&
837 getCurScope()->isInObjcMethodScope() &&
838 ((Tok.is(tok::identifier) &&
839 (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) ||
840 Tok.is(tok::code_completion))) {
841 Res = ParseObjCMessageExpressionBody(SourceLocation(), ILoc, ParsedType(),
842 0);
843 break;
844 }
845
846 // If we have an Objective-C class name followed by an identifier
847 // and either ':' or ']', this is an Objective-C class message
848 // send that's missing the opening '['. Recovery
849 // appropriately. Also take this path if we're performing code
850 // completion after an Objective-C class name.
851 if (getLangOpts().ObjC1 &&
852 ((Tok.is(tok::identifier) && !InMessageExpression) ||
853 Tok.is(tok::code_completion))) {
854 const Token& Next = NextToken();
855 if (Tok.is(tok::code_completion) ||
856 Next.is(tok::colon) || Next.is(tok::r_square))
857 if (ParsedType Typ = Actions.getTypeName(II, ILoc, getCurScope()))
858 if (Typ.get()->isObjCObjectOrInterfaceType()) {
859 // Fake up a Declarator to use with ActOnTypeName.
860 DeclSpec DS(AttrFactory);
861 DS.SetRangeStart(ILoc);
862 DS.SetRangeEnd(ILoc);
863 const char *PrevSpec = 0;
864 unsigned DiagID;
865 DS.SetTypeSpecType(TST_typename, ILoc, PrevSpec, DiagID, Typ);
866
867 Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
868 TypeResult Ty = Actions.ActOnTypeName(getCurScope(),
869 DeclaratorInfo);
870 if (Ty.isInvalid())
871 break;
872
873 Res = ParseObjCMessageExpressionBody(SourceLocation(),
874 SourceLocation(),
875 Ty.get(), 0);
876 break;
877 }
878 }
879
880 // Make sure to pass down the right value for isAddressOfOperand.
881 if (isAddressOfOperand && isPostfixExpressionSuffixStart())
882 isAddressOfOperand = false;
883
884 // Function designators are allowed to be undeclared (C99 6.5.1p2), so we
885 // need to know whether or not this identifier is a function designator or
886 // not.
887 UnqualifiedId Name;
888 CXXScopeSpec ScopeSpec;
889 SourceLocation TemplateKWLoc;
890 CastExpressionIdValidator Validator(isTypeCast != NotTypeCast,
891 isTypeCast != IsTypeCast);
892 Name.setIdentifier(&II, ILoc);
893 Res = Actions.ActOnIdExpression(getCurScope(), ScopeSpec, TemplateKWLoc,
894 Name, Tok.is(tok::l_paren),
895 isAddressOfOperand, &Validator);
896 break;
897 }
898 case tok::char_constant: // constant: character-constant
899 case tok::wide_char_constant:
900 case tok::utf16_char_constant:
901 case tok::utf32_char_constant:
902 Res = Actions.ActOnCharacterConstant(Tok, /*UDLScope*/getCurScope());
903 ConsumeToken();
904 break;
905 case tok::kw___func__: // primary-expression: __func__ [C99 6.4.2.2]
906 case tok::kw___FUNCTION__: // primary-expression: __FUNCTION__ [GNU]
907 case tok::kw_L__FUNCTION__: // primary-expression: L__FUNCTION__ [MS]
908 case tok::kw___PRETTY_FUNCTION__: // primary-expression: __P..Y_F..N__ [GNU]
909 Res = Actions.ActOnPredefinedExpr(Tok.getLocation(), SavedKind);
910 ConsumeToken();
911 break;
912 case tok::string_literal: // primary-expression: string-literal
913 case tok::wide_string_literal:
914 case tok::utf8_string_literal:
915 case tok::utf16_string_literal:
916 case tok::utf32_string_literal:
917 Res = ParseStringLiteralExpression(true);
918 break;
919 case tok::kw__Generic: // primary-expression: generic-selection [C11 6.5.1]
920 Res = ParseGenericSelectionExpression();
921 break;
922 case tok::kw___builtin_va_arg:
923 case tok::kw___builtin_offsetof:
924 case tok::kw___builtin_choose_expr:
925 case tok::kw___builtin_astype: // primary-expression: [OCL] as_type()
926 return ParseBuiltinPrimaryExpression();
927 case tok::kw___null:
928 return Actions.ActOnGNUNullExpr(ConsumeToken());
929
930 case tok::plusplus: // unary-expression: '++' unary-expression [C99]
931 case tok::minusminus: { // unary-expression: '--' unary-expression [C99]
932 // C++ [expr.unary] has:
933 // unary-expression:
934 // ++ cast-expression
935 // -- cast-expression
936 SourceLocation SavedLoc = ConsumeToken();
937 Res = ParseCastExpression(!getLangOpts().CPlusPlus);
938 if (!Res.isInvalid())
939 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get());
940 return Res;
941 }
942 case tok::amp: { // unary-expression: '&' cast-expression
943 // Special treatment because of member pointers
944 SourceLocation SavedLoc = ConsumeToken();
945 Res = ParseCastExpression(false, true);
946 if (!Res.isInvalid())
947 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get());
948 return Res;
949 }
950
951 case tok::star: // unary-expression: '*' cast-expression
952 case tok::plus: // unary-expression: '+' cast-expression
953 case tok::minus: // unary-expression: '-' cast-expression
954 case tok::tilde: // unary-expression: '~' cast-expression
955 case tok::exclaim: // unary-expression: '!' cast-expression
956 case tok::kw___real: // unary-expression: '__real' cast-expression [GNU]
957 case tok::kw___imag: { // unary-expression: '__imag' cast-expression [GNU]
958 SourceLocation SavedLoc = ConsumeToken();
959 Res = ParseCastExpression(false);
960 if (!Res.isInvalid())
961 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get());
962 return Res;
963 }
964
965 case tok::kw___extension__:{//unary-expression:'__extension__' cast-expr [GNU]
966 // __extension__ silences extension warnings in the subexpression.
967 ExtensionRAIIObject O(Diags); // Use RAII to do this.
968 SourceLocation SavedLoc = ConsumeToken();
969 Res = ParseCastExpression(false);
970 if (!Res.isInvalid())
971 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get());
972 return Res;
973 }
974 case tok::kw__Alignof: // unary-expression: '_Alignof' '(' type-name ')'
975 if (!getLangOpts().C11)
976 Diag(Tok, diag::ext_c11_alignment) << Tok.getName();
977 // fallthrough
978 case tok::kw_alignof: // unary-expression: 'alignof' '(' type-id ')'
979 case tok::kw___alignof: // unary-expression: '__alignof' unary-expression
980 // unary-expression: '__alignof' '(' type-name ')'
981 case tok::kw_sizeof: // unary-expression: 'sizeof' unary-expression
982 // unary-expression: 'sizeof' '(' type-name ')'
983 case tok::kw_vec_step: // unary-expression: OpenCL 'vec_step' expression
984 return ParseUnaryExprOrTypeTraitExpression();
985 case tok::ampamp: { // unary-expression: '&&' identifier
986 SourceLocation AmpAmpLoc = ConsumeToken();
987 if (Tok.isNot(tok::identifier))
988 return ExprError(Diag(Tok, diag::err_expected_ident));
989
990 if (getCurScope()->getFnParent() == 0)
991 return ExprError(Diag(Tok, diag::err_address_of_label_outside_fn));
992
993 Diag(AmpAmpLoc, diag::ext_gnu_address_of_label);
994 LabelDecl *LD = Actions.LookupOrCreateLabel(Tok.getIdentifierInfo(),
995 Tok.getLocation());
996 Res = Actions.ActOnAddrLabel(AmpAmpLoc, Tok.getLocation(), LD);
997 ConsumeToken();
998 return Res;
999 }
1000 case tok::kw_const_cast:
1001 case tok::kw_dynamic_cast:
1002 case tok::kw_reinterpret_cast:
1003 case tok::kw_static_cast:
1004 Res = ParseCXXCasts();
1005 break;
1006 case tok::kw_typeid:
1007 Res = ParseCXXTypeid();
1008 break;
1009 case tok::kw___uuidof:
1010 Res = ParseCXXUuidof();
1011 break;
1012 case tok::kw_this:
1013 Res = ParseCXXThis();
1014 break;
1015
1016 case tok::annot_typename:
1017 if (isStartOfObjCClassMessageMissingOpenBracket()) {
1018 ParsedType Type = getTypeAnnotation(Tok);
1019
1020 // Fake up a Declarator to use with ActOnTypeName.
1021 DeclSpec DS(AttrFactory);
1022 DS.SetRangeStart(Tok.getLocation());
1023 DS.SetRangeEnd(Tok.getLastLoc());
1024
1025 const char *PrevSpec = 0;
1026 unsigned DiagID;
1027 DS.SetTypeSpecType(TST_typename, Tok.getAnnotationEndLoc(),
1028 PrevSpec, DiagID, Type);
1029
1030 Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
1031 TypeResult Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo);
1032 if (Ty.isInvalid())
1033 break;
1034
1035 ConsumeToken();
1036 Res = ParseObjCMessageExpressionBody(SourceLocation(), SourceLocation(),
1037 Ty.get(), 0);
1038 break;
1039 }
1040 // Fall through
1041
1042 case tok::annot_decltype:
1043 case tok::kw_char:
1044 case tok::kw_wchar_t:
1045 case tok::kw_char16_t:
1046 case tok::kw_char32_t:
1047 case tok::kw_bool:
1048 case tok::kw_short:
1049 case tok::kw_int:
1050 case tok::kw_long:
1051 case tok::kw___int64:
1052 case tok::kw___int128:
1053 case tok::kw_signed:
1054 case tok::kw_unsigned:
1055 case tok::kw_half:
1056 case tok::kw_float:
1057 case tok::kw_double:
1058 case tok::kw_void:
1059 case tok::kw_typename:
1060 case tok::kw_typeof:
1061 case tok::kw___vector: {
1062 if (!getLangOpts().CPlusPlus) {
1063 Diag(Tok, diag::err_expected_expression);
1064 return ExprError();
1065 }
1066
1067 if (SavedKind == tok::kw_typename) {
1068 // postfix-expression: typename-specifier '(' expression-list[opt] ')'
1069 // typename-specifier braced-init-list
1070 if (TryAnnotateTypeOrScopeToken())
1071 return ExprError();
1072 }
1073
1074 // postfix-expression: simple-type-specifier '(' expression-list[opt] ')'
1075 // simple-type-specifier braced-init-list
1076 //
1077 DeclSpec DS(AttrFactory);
1078 ParseCXXSimpleTypeSpecifier(DS);
1079 if (Tok.isNot(tok::l_paren) &&
1080 (!getLangOpts().CPlusPlus0x || Tok.isNot(tok::l_brace)))
1081 return ExprError(Diag(Tok, diag::err_expected_lparen_after_type)
1082 << DS.getSourceRange());
1083
1084 if (Tok.is(tok::l_brace))
1085 Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists);
1086
1087 Res = ParseCXXTypeConstructExpression(DS);
1088 break;
1089 }
1090
1091 case tok::annot_cxxscope: { // [C++] id-expression: qualified-id
1092 // If TryAnnotateTypeOrScopeToken annotates the token, tail recurse.
1093 // (We can end up in this situation after tentative parsing.)
1094 if (TryAnnotateTypeOrScopeToken())
1095 return ExprError();
1096 if (!Tok.is(tok::annot_cxxscope))
1097 return ParseCastExpression(isUnaryExpression, isAddressOfOperand,
1098 NotCastExpr, isTypeCast);
1099
1100 Token Next = NextToken();
1101 if (Next.is(tok::annot_template_id)) {
1102 TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Next);
1103 if (TemplateId->Kind == TNK_Type_template) {
1104 // We have a qualified template-id that we know refers to a
1105 // type, translate it into a type and continue parsing as a
1106 // cast expression.
1107 CXXScopeSpec SS;
1108 ParseOptionalCXXScopeSpecifier(SS, ParsedType(),
1109 /*EnteringContext=*/false);
1110 AnnotateTemplateIdTokenAsType();
1111 return ParseCastExpression(isUnaryExpression, isAddressOfOperand,
1112 NotCastExpr, isTypeCast);
1113 }
1114 }
1115
1116 // Parse as an id-expression.
1117 Res = ParseCXXIdExpression(isAddressOfOperand);
1118 break;
1119 }
1120
1121 case tok::annot_template_id: { // [C++] template-id
1122 TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok);
1123 if (TemplateId->Kind == TNK_Type_template) {
1124 // We have a template-id that we know refers to a type,
1125 // translate it into a type and continue parsing as a cast
1126 // expression.
1127 AnnotateTemplateIdTokenAsType();
1128 return ParseCastExpression(isUnaryExpression, isAddressOfOperand,
1129 NotCastExpr, isTypeCast);
1130 }
1131
1132 // Fall through to treat the template-id as an id-expression.
1133 }
1134
1135 case tok::kw_operator: // [C++] id-expression: operator/conversion-function-id
1136 Res = ParseCXXIdExpression(isAddressOfOperand);
1137 break;
1138
1139 case tok::coloncolon: {
1140 // ::foo::bar -> global qualified name etc. If TryAnnotateTypeOrScopeToken
1141 // annotates the token, tail recurse.
1142 if (TryAnnotateTypeOrScopeToken())
1143 return ExprError();
1144 if (!Tok.is(tok::coloncolon))
1145 return ParseCastExpression(isUnaryExpression, isAddressOfOperand);
1146
1147 // ::new -> [C++] new-expression
1148 // ::delete -> [C++] delete-expression
1149 SourceLocation CCLoc = ConsumeToken();
1150 if (Tok.is(tok::kw_new))
1151 return ParseCXXNewExpression(true, CCLoc);
1152 if (Tok.is(tok::kw_delete))
1153 return ParseCXXDeleteExpression(true, CCLoc);
1154
1155 // This is not a type name or scope specifier, it is an invalid expression.
1156 Diag(CCLoc, diag::err_expected_expression);
1157 return ExprError();
1158 }
1159
1160 case tok::kw_new: // [C++] new-expression
1161 return ParseCXXNewExpression(false, Tok.getLocation());
1162
1163 case tok::kw_delete: // [C++] delete-expression
1164 return ParseCXXDeleteExpression(false, Tok.getLocation());
1165
1166 case tok::kw_noexcept: { // [C++0x] 'noexcept' '(' expression ')'
1167 Diag(Tok, diag::warn_cxx98_compat_noexcept_expr);
1168 SourceLocation KeyLoc = ConsumeToken();
1169 BalancedDelimiterTracker T(*this, tok::l_paren);
1170
1171 if (T.expectAndConsume(diag::err_expected_lparen_after, "noexcept"))
1172 return ExprError();
1173 // C++11 [expr.unary.noexcept]p1:
1174 // The noexcept operator determines whether the evaluation of its operand,
1175 // which is an unevaluated operand, can throw an exception.
1176 EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated);
1177 ExprResult Result = ParseExpression();
1178
1179 T.consumeClose();
1180
1181 if (!Result.isInvalid())
1182 Result = Actions.ActOnNoexceptExpr(KeyLoc, T.getOpenLocation(),
1183 Result.take(), T.getCloseLocation());
1184 return Result;
1185 }
1186
1187 case tok::kw___is_abstract: // [GNU] unary-type-trait
1188 case tok::kw___is_class:
1189 case tok::kw___is_empty:
1190 case tok::kw___is_enum:
1191 case tok::kw___is_literal:
1192 case tok::kw___is_arithmetic:
1193 case tok::kw___is_integral:
1194 case tok::kw___is_floating_point:
1195 case tok::kw___is_complete_type:
1196 case tok::kw___is_void:
1197 case tok::kw___is_array:
1198 case tok::kw___is_function:
1199 case tok::kw___is_reference:
1200 case tok::kw___is_lvalue_reference:
1201 case tok::kw___is_rvalue_reference:
1202 case tok::kw___is_fundamental:
1203 case tok::kw___is_object:
1204 case tok::kw___is_scalar:
1205 case tok::kw___is_compound:
1206 case tok::kw___is_pointer:
1207 case tok::kw___is_member_object_pointer:
1208 case tok::kw___is_member_function_pointer:
1209 case tok::kw___is_member_pointer:
1210 case tok::kw___is_const:
1211 case tok::kw___is_volatile:
1212 case tok::kw___is_standard_layout:
1213 case tok::kw___is_signed:
1214 case tok::kw___is_unsigned:
1215 case tok::kw___is_literal_type:
1216 case tok::kw___is_pod:
1217 case tok::kw___is_polymorphic:
1218 case tok::kw___is_trivial:
1219 case tok::kw___is_trivially_copyable:
1220 case tok::kw___is_union:
1221 case tok::kw___is_final:
1222 case tok::kw___has_trivial_constructor:
1223 case tok::kw___has_trivial_copy:
1224 case tok::kw___has_trivial_assign:
1225 case tok::kw___has_trivial_destructor:
1226 case tok::kw___has_nothrow_assign:
1227 case tok::kw___has_nothrow_copy:
1228 case tok::kw___has_nothrow_constructor:
1229 case tok::kw___has_virtual_destructor:
1230 return ParseUnaryTypeTrait();
1231
1232 case tok::kw___builtin_types_compatible_p:
1233 case tok::kw___is_base_of:
1234 case tok::kw___is_same:
1235 case tok::kw___is_convertible:
1236 case tok::kw___is_convertible_to:
1237 case tok::kw___is_trivially_assignable:
1238 return ParseBinaryTypeTrait();
1239
1240 case tok::kw___is_trivially_constructible:
1241 return ParseTypeTrait();
1242
1243 case tok::kw___array_rank:
1244 case tok::kw___array_extent:
1245 return ParseArrayTypeTrait();
1246
1247 case tok::kw___is_lvalue_expr:
1248 case tok::kw___is_rvalue_expr:
1249 return ParseExpressionTrait();
1250
1251 case tok::at: {
1252 SourceLocation AtLoc = ConsumeToken();
1253 return ParseObjCAtExpression(AtLoc);
1254 }
1255 case tok::caret:
1256 Res = ParseBlockLiteralExpression();
1257 break;
1258 case tok::code_completion: {
1259 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Expression);
1260 cutOffParsing();
1261 return ExprError();
1262 }
1263 case tok::l_square:
1264 if (getLangOpts().CPlusPlus0x) {
1265 if (getLangOpts().ObjC1) {
1266 // C++11 lambda expressions and Objective-C message sends both start with a
1267 // square bracket. There are three possibilities here:
1268 // we have a valid lambda expression, we have an invalid lambda
1269 // expression, or we have something that doesn't appear to be a lambda.
1270 // If we're in the last case, we fall back to ParseObjCMessageExpression.
1271 Res = TryParseLambdaExpression();
1272 if (!Res.isInvalid() && !Res.get())
1273 Res = ParseObjCMessageExpression();
1274 break;
1275 }
1276 Res = ParseLambdaExpression();
1277 break;
1278 }
1279 if (getLangOpts().ObjC1) {
1280 Res = ParseObjCMessageExpression();
1281 break;
1282 }
1283 // FALL THROUGH.
1284 default:
1285 NotCastExpr = true;
1286 return ExprError();
1287 }
1288
1289 // These can be followed by postfix-expr pieces.
1290 return ParsePostfixExpressionSuffix(Res);
1291 }
1292
1293 /// \brief Once the leading part of a postfix-expression is parsed, this
1294 /// method parses any suffixes that apply.
1295 ///
1296 /// \verbatim
1297 /// postfix-expression: [C99 6.5.2]
1298 /// primary-expression
1299 /// postfix-expression '[' expression ']'
1300 /// postfix-expression '[' braced-init-list ']'
1301 /// postfix-expression '(' argument-expression-list[opt] ')'
1302 /// postfix-expression '.' identifier
1303 /// postfix-expression '->' identifier
1304 /// postfix-expression '++'
1305 /// postfix-expression '--'
1306 /// '(' type-name ')' '{' initializer-list '}'
1307 /// '(' type-name ')' '{' initializer-list ',' '}'
1308 ///
1309 /// argument-expression-list: [C99 6.5.2]
1310 /// argument-expression ...[opt]
1311 /// argument-expression-list ',' assignment-expression ...[opt]
1312 /// \endverbatim
1313 ExprResult
ParsePostfixExpressionSuffix(ExprResult LHS)1314 Parser::ParsePostfixExpressionSuffix(ExprResult LHS) {
1315 // Now that the primary-expression piece of the postfix-expression has been
1316 // parsed, see if there are any postfix-expression pieces here.
1317 SourceLocation Loc;
1318 while (1) {
1319 switch (Tok.getKind()) {
1320 case tok::code_completion:
1321 if (InMessageExpression)
1322 return LHS;
1323
1324 Actions.CodeCompletePostfixExpression(getCurScope(), LHS);
1325 cutOffParsing();
1326 return ExprError();
1327
1328 case tok::identifier:
1329 // If we see identifier: after an expression, and we're not already in a
1330 // message send, then this is probably a message send with a missing
1331 // opening bracket '['.
1332 if (getLangOpts().ObjC1 && !InMessageExpression &&
1333 (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) {
1334 LHS = ParseObjCMessageExpressionBody(SourceLocation(), SourceLocation(),
1335 ParsedType(), LHS.get());
1336 break;
1337 }
1338
1339 // Fall through; this isn't a message send.
1340
1341 default: // Not a postfix-expression suffix.
1342 return LHS;
1343 case tok::l_square: { // postfix-expression: p-e '[' expression ']'
1344 // If we have a array postfix expression that starts on a new line and
1345 // Objective-C is enabled, it is highly likely that the user forgot a
1346 // semicolon after the base expression and that the array postfix-expr is
1347 // actually another message send. In this case, do some look-ahead to see
1348 // if the contents of the square brackets are obviously not a valid
1349 // expression and recover by pretending there is no suffix.
1350 if (getLangOpts().ObjC1 && Tok.isAtStartOfLine() &&
1351 isSimpleObjCMessageExpression())
1352 return LHS;
1353
1354 // Reject array indices starting with a lambda-expression. '[[' is
1355 // reserved for attributes.
1356 if (CheckProhibitedCXX11Attribute())
1357 return ExprError();
1358
1359 BalancedDelimiterTracker T(*this, tok::l_square);
1360 T.consumeOpen();
1361 Loc = T.getOpenLocation();
1362 ExprResult Idx;
1363 if (getLangOpts().CPlusPlus0x && Tok.is(tok::l_brace)) {
1364 Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists);
1365 Idx = ParseBraceInitializer();
1366 } else
1367 Idx = ParseExpression();
1368
1369 SourceLocation RLoc = Tok.getLocation();
1370
1371 if (!LHS.isInvalid() && !Idx.isInvalid() && Tok.is(tok::r_square)) {
1372 LHS = Actions.ActOnArraySubscriptExpr(getCurScope(), LHS.take(), Loc,
1373 Idx.take(), RLoc);
1374 } else
1375 LHS = ExprError();
1376
1377 // Match the ']'.
1378 T.consumeClose();
1379 break;
1380 }
1381
1382 case tok::l_paren: // p-e: p-e '(' argument-expression-list[opt] ')'
1383 case tok::lesslessless: { // p-e: p-e '<<<' argument-expression-list '>>>'
1384 // '(' argument-expression-list[opt] ')'
1385 tok::TokenKind OpKind = Tok.getKind();
1386 InMessageExpressionRAIIObject InMessage(*this, false);
1387
1388 Expr *ExecConfig = 0;
1389
1390 BalancedDelimiterTracker PT(*this, tok::l_paren);
1391
1392 if (OpKind == tok::lesslessless) {
1393 ExprVector ExecConfigExprs;
1394 CommaLocsTy ExecConfigCommaLocs;
1395 SourceLocation OpenLoc = ConsumeToken();
1396
1397 if (ParseExpressionList(ExecConfigExprs, ExecConfigCommaLocs)) {
1398 LHS = ExprError();
1399 }
1400
1401 SourceLocation CloseLoc = Tok.getLocation();
1402 if (Tok.is(tok::greatergreatergreater)) {
1403 ConsumeToken();
1404 } else if (LHS.isInvalid()) {
1405 SkipUntil(tok::greatergreatergreater);
1406 } else {
1407 // There was an error closing the brackets
1408 Diag(Tok, diag::err_expected_ggg);
1409 Diag(OpenLoc, diag::note_matching) << "<<<";
1410 SkipUntil(tok::greatergreatergreater);
1411 LHS = ExprError();
1412 }
1413
1414 if (!LHS.isInvalid()) {
1415 if (ExpectAndConsume(tok::l_paren, diag::err_expected_lparen, ""))
1416 LHS = ExprError();
1417 else
1418 Loc = PrevTokLocation;
1419 }
1420
1421 if (!LHS.isInvalid()) {
1422 ExprResult ECResult = Actions.ActOnCUDAExecConfigExpr(getCurScope(),
1423 OpenLoc,
1424 ExecConfigExprs,
1425 CloseLoc);
1426 if (ECResult.isInvalid())
1427 LHS = ExprError();
1428 else
1429 ExecConfig = ECResult.get();
1430 }
1431 } else {
1432 PT.consumeOpen();
1433 Loc = PT.getOpenLocation();
1434 }
1435
1436 ExprVector ArgExprs;
1437 CommaLocsTy CommaLocs;
1438
1439 if (Tok.is(tok::code_completion)) {
1440 Actions.CodeCompleteCall(getCurScope(), LHS.get(),
1441 llvm::ArrayRef<Expr *>());
1442 cutOffParsing();
1443 return ExprError();
1444 }
1445
1446 if (OpKind == tok::l_paren || !LHS.isInvalid()) {
1447 if (Tok.isNot(tok::r_paren)) {
1448 if (ParseExpressionList(ArgExprs, CommaLocs, &Sema::CodeCompleteCall,
1449 LHS.get())) {
1450 LHS = ExprError();
1451 }
1452 }
1453 }
1454
1455 // Match the ')'.
1456 if (LHS.isInvalid()) {
1457 SkipUntil(tok::r_paren);
1458 } else if (Tok.isNot(tok::r_paren)) {
1459 PT.consumeClose();
1460 LHS = ExprError();
1461 } else {
1462 assert((ArgExprs.size() == 0 ||
1463 ArgExprs.size()-1 == CommaLocs.size())&&
1464 "Unexpected number of commas!");
1465 LHS = Actions.ActOnCallExpr(getCurScope(), LHS.take(), Loc,
1466 ArgExprs, Tok.getLocation(),
1467 ExecConfig);
1468 PT.consumeClose();
1469 }
1470
1471 break;
1472 }
1473 case tok::arrow:
1474 case tok::period: {
1475 // postfix-expression: p-e '->' template[opt] id-expression
1476 // postfix-expression: p-e '.' template[opt] id-expression
1477 tok::TokenKind OpKind = Tok.getKind();
1478 SourceLocation OpLoc = ConsumeToken(); // Eat the "." or "->" token.
1479
1480 CXXScopeSpec SS;
1481 ParsedType ObjectType;
1482 bool MayBePseudoDestructor = false;
1483 if (getLangOpts().CPlusPlus && !LHS.isInvalid()) {
1484 LHS = Actions.ActOnStartCXXMemberReference(getCurScope(), LHS.take(),
1485 OpLoc, OpKind, ObjectType,
1486 MayBePseudoDestructor);
1487 if (LHS.isInvalid())
1488 break;
1489
1490 ParseOptionalCXXScopeSpecifier(SS, ObjectType,
1491 /*EnteringContext=*/false,
1492 &MayBePseudoDestructor);
1493 if (SS.isNotEmpty())
1494 ObjectType = ParsedType();
1495 }
1496
1497 if (Tok.is(tok::code_completion)) {
1498 // Code completion for a member access expression.
1499 Actions.CodeCompleteMemberReferenceExpr(getCurScope(), LHS.get(),
1500 OpLoc, OpKind == tok::arrow);
1501
1502 cutOffParsing();
1503 return ExprError();
1504 }
1505
1506 if (MayBePseudoDestructor && !LHS.isInvalid()) {
1507 LHS = ParseCXXPseudoDestructor(LHS.take(), OpLoc, OpKind, SS,
1508 ObjectType);
1509 break;
1510 }
1511
1512 // Either the action has told is that this cannot be a
1513 // pseudo-destructor expression (based on the type of base
1514 // expression), or we didn't see a '~' in the right place. We
1515 // can still parse a destructor name here, but in that case it
1516 // names a real destructor.
1517 // Allow explicit constructor calls in Microsoft mode.
1518 // FIXME: Add support for explicit call of template constructor.
1519 SourceLocation TemplateKWLoc;
1520 UnqualifiedId Name;
1521 if (getLangOpts().ObjC2 && OpKind == tok::period && Tok.is(tok::kw_class)) {
1522 // Objective-C++:
1523 // After a '.' in a member access expression, treat the keyword
1524 // 'class' as if it were an identifier.
1525 //
1526 // This hack allows property access to the 'class' method because it is
1527 // such a common method name. For other C++ keywords that are
1528 // Objective-C method names, one must use the message send syntax.
1529 IdentifierInfo *Id = Tok.getIdentifierInfo();
1530 SourceLocation Loc = ConsumeToken();
1531 Name.setIdentifier(Id, Loc);
1532 } else if (ParseUnqualifiedId(SS,
1533 /*EnteringContext=*/false,
1534 /*AllowDestructorName=*/true,
1535 /*AllowConstructorName=*/
1536 getLangOpts().MicrosoftExt,
1537 ObjectType, TemplateKWLoc, Name))
1538 LHS = ExprError();
1539
1540 if (!LHS.isInvalid())
1541 LHS = Actions.ActOnMemberAccessExpr(getCurScope(), LHS.take(), OpLoc,
1542 OpKind, SS, TemplateKWLoc, Name,
1543 CurParsedObjCImpl ? CurParsedObjCImpl->Dcl : 0,
1544 Tok.is(tok::l_paren));
1545 break;
1546 }
1547 case tok::plusplus: // postfix-expression: postfix-expression '++'
1548 case tok::minusminus: // postfix-expression: postfix-expression '--'
1549 if (!LHS.isInvalid()) {
1550 LHS = Actions.ActOnPostfixUnaryOp(getCurScope(), Tok.getLocation(),
1551 Tok.getKind(), LHS.take());
1552 }
1553 ConsumeToken();
1554 break;
1555 }
1556 }
1557 }
1558
1559 /// ParseExprAfterUnaryExprOrTypeTrait - We parsed a typeof/sizeof/alignof/
1560 /// vec_step and we are at the start of an expression or a parenthesized
1561 /// type-id. OpTok is the operand token (typeof/sizeof/alignof). Returns the
1562 /// expression (isCastExpr == false) or the type (isCastExpr == true).
1563 ///
1564 /// \verbatim
1565 /// unary-expression: [C99 6.5.3]
1566 /// 'sizeof' unary-expression
1567 /// 'sizeof' '(' type-name ')'
1568 /// [GNU] '__alignof' unary-expression
1569 /// [GNU] '__alignof' '(' type-name ')'
1570 /// [C11] '_Alignof' '(' type-name ')'
1571 /// [C++0x] 'alignof' '(' type-id ')'
1572 ///
1573 /// [GNU] typeof-specifier:
1574 /// typeof ( expressions )
1575 /// typeof ( type-name )
1576 /// [GNU/C++] typeof unary-expression
1577 ///
1578 /// [OpenCL 1.1 6.11.12] vec_step built-in function:
1579 /// vec_step ( expressions )
1580 /// vec_step ( type-name )
1581 /// \endverbatim
1582 ExprResult
ParseExprAfterUnaryExprOrTypeTrait(const Token & OpTok,bool & isCastExpr,ParsedType & CastTy,SourceRange & CastRange)1583 Parser::ParseExprAfterUnaryExprOrTypeTrait(const Token &OpTok,
1584 bool &isCastExpr,
1585 ParsedType &CastTy,
1586 SourceRange &CastRange) {
1587
1588 assert((OpTok.is(tok::kw_typeof) || OpTok.is(tok::kw_sizeof) ||
1589 OpTok.is(tok::kw___alignof) || OpTok.is(tok::kw_alignof) ||
1590 OpTok.is(tok::kw__Alignof) || OpTok.is(tok::kw_vec_step)) &&
1591 "Not a typeof/sizeof/alignof/vec_step expression!");
1592
1593 ExprResult Operand;
1594
1595 // If the operand doesn't start with an '(', it must be an expression.
1596 if (Tok.isNot(tok::l_paren)) {
1597 isCastExpr = false;
1598 if (OpTok.is(tok::kw_typeof) && !getLangOpts().CPlusPlus) {
1599 Diag(Tok,diag::err_expected_lparen_after_id) << OpTok.getIdentifierInfo();
1600 return ExprError();
1601 }
1602
1603 Operand = ParseCastExpression(true/*isUnaryExpression*/);
1604 } else {
1605 // If it starts with a '(', we know that it is either a parenthesized
1606 // type-name, or it is a unary-expression that starts with a compound
1607 // literal, or starts with a primary-expression that is a parenthesized
1608 // expression.
1609 ParenParseOption ExprType = CastExpr;
1610 SourceLocation LParenLoc = Tok.getLocation(), RParenLoc;
1611
1612 Operand = ParseParenExpression(ExprType, true/*stopIfCastExpr*/,
1613 false, CastTy, RParenLoc);
1614 CastRange = SourceRange(LParenLoc, RParenLoc);
1615
1616 // If ParseParenExpression parsed a '(typename)' sequence only, then this is
1617 // a type.
1618 if (ExprType == CastExpr) {
1619 isCastExpr = true;
1620 return ExprEmpty();
1621 }
1622
1623 if (getLangOpts().CPlusPlus || OpTok.isNot(tok::kw_typeof)) {
1624 // GNU typeof in C requires the expression to be parenthesized. Not so for
1625 // sizeof/alignof or in C++. Therefore, the parenthesized expression is
1626 // the start of a unary-expression, but doesn't include any postfix
1627 // pieces. Parse these now if present.
1628 if (!Operand.isInvalid())
1629 Operand = ParsePostfixExpressionSuffix(Operand.get());
1630 }
1631 }
1632
1633 // If we get here, the operand to the typeof/sizeof/alignof was an expresion.
1634 isCastExpr = false;
1635 return Operand;
1636 }
1637
1638
1639 /// \brief Parse a sizeof or alignof expression.
1640 ///
1641 /// \verbatim
1642 /// unary-expression: [C99 6.5.3]
1643 /// 'sizeof' unary-expression
1644 /// 'sizeof' '(' type-name ')'
1645 /// [C++0x] 'sizeof' '...' '(' identifier ')'
1646 /// [GNU] '__alignof' unary-expression
1647 /// [GNU] '__alignof' '(' type-name ')'
1648 /// [C11] '_Alignof' '(' type-name ')'
1649 /// [C++0x] 'alignof' '(' type-id ')'
1650 /// \endverbatim
ParseUnaryExprOrTypeTraitExpression()1651 ExprResult Parser::ParseUnaryExprOrTypeTraitExpression() {
1652 assert((Tok.is(tok::kw_sizeof) || Tok.is(tok::kw___alignof) ||
1653 Tok.is(tok::kw_alignof) || Tok.is(tok::kw__Alignof) ||
1654 Tok.is(tok::kw_vec_step)) &&
1655 "Not a sizeof/alignof/vec_step expression!");
1656 Token OpTok = Tok;
1657 ConsumeToken();
1658
1659 // [C++0x] 'sizeof' '...' '(' identifier ')'
1660 if (Tok.is(tok::ellipsis) && OpTok.is(tok::kw_sizeof)) {
1661 SourceLocation EllipsisLoc = ConsumeToken();
1662 SourceLocation LParenLoc, RParenLoc;
1663 IdentifierInfo *Name = 0;
1664 SourceLocation NameLoc;
1665 if (Tok.is(tok::l_paren)) {
1666 BalancedDelimiterTracker T(*this, tok::l_paren);
1667 T.consumeOpen();
1668 LParenLoc = T.getOpenLocation();
1669 if (Tok.is(tok::identifier)) {
1670 Name = Tok.getIdentifierInfo();
1671 NameLoc = ConsumeToken();
1672 T.consumeClose();
1673 RParenLoc = T.getCloseLocation();
1674 if (RParenLoc.isInvalid())
1675 RParenLoc = PP.getLocForEndOfToken(NameLoc);
1676 } else {
1677 Diag(Tok, diag::err_expected_parameter_pack);
1678 SkipUntil(tok::r_paren);
1679 }
1680 } else if (Tok.is(tok::identifier)) {
1681 Name = Tok.getIdentifierInfo();
1682 NameLoc = ConsumeToken();
1683 LParenLoc = PP.getLocForEndOfToken(EllipsisLoc);
1684 RParenLoc = PP.getLocForEndOfToken(NameLoc);
1685 Diag(LParenLoc, diag::err_paren_sizeof_parameter_pack)
1686 << Name
1687 << FixItHint::CreateInsertion(LParenLoc, "(")
1688 << FixItHint::CreateInsertion(RParenLoc, ")");
1689 } else {
1690 Diag(Tok, diag::err_sizeof_parameter_pack);
1691 }
1692
1693 if (!Name)
1694 return ExprError();
1695
1696 return Actions.ActOnSizeofParameterPackExpr(getCurScope(),
1697 OpTok.getLocation(),
1698 *Name, NameLoc,
1699 RParenLoc);
1700 }
1701
1702 if (OpTok.is(tok::kw_alignof) || OpTok.is(tok::kw__Alignof))
1703 Diag(OpTok, diag::warn_cxx98_compat_alignof);
1704
1705 EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated);
1706
1707 bool isCastExpr;
1708 ParsedType CastTy;
1709 SourceRange CastRange;
1710 ExprResult Operand = ParseExprAfterUnaryExprOrTypeTrait(OpTok,
1711 isCastExpr,
1712 CastTy,
1713 CastRange);
1714
1715 UnaryExprOrTypeTrait ExprKind = UETT_SizeOf;
1716 if (OpTok.is(tok::kw_alignof) || OpTok.is(tok::kw___alignof) ||
1717 OpTok.is(tok::kw__Alignof))
1718 ExprKind = UETT_AlignOf;
1719 else if (OpTok.is(tok::kw_vec_step))
1720 ExprKind = UETT_VecStep;
1721
1722 if (isCastExpr)
1723 return Actions.ActOnUnaryExprOrTypeTraitExpr(OpTok.getLocation(),
1724 ExprKind,
1725 /*isType=*/true,
1726 CastTy.getAsOpaquePtr(),
1727 CastRange);
1728
1729 // If we get here, the operand to the sizeof/alignof was an expresion.
1730 if (!Operand.isInvalid())
1731 Operand = Actions.ActOnUnaryExprOrTypeTraitExpr(OpTok.getLocation(),
1732 ExprKind,
1733 /*isType=*/false,
1734 Operand.release(),
1735 CastRange);
1736 return Operand;
1737 }
1738
1739 /// ParseBuiltinPrimaryExpression
1740 ///
1741 /// \verbatim
1742 /// primary-expression: [C99 6.5.1]
1743 /// [GNU] '__builtin_va_arg' '(' assignment-expression ',' type-name ')'
1744 /// [GNU] '__builtin_offsetof' '(' type-name ',' offsetof-member-designator')'
1745 /// [GNU] '__builtin_choose_expr' '(' assign-expr ',' assign-expr ','
1746 /// assign-expr ')'
1747 /// [GNU] '__builtin_types_compatible_p' '(' type-name ',' type-name ')'
1748 /// [OCL] '__builtin_astype' '(' assignment-expression ',' type-name ')'
1749 ///
1750 /// [GNU] offsetof-member-designator:
1751 /// [GNU] identifier
1752 /// [GNU] offsetof-member-designator '.' identifier
1753 /// [GNU] offsetof-member-designator '[' expression ']'
1754 /// \endverbatim
ParseBuiltinPrimaryExpression()1755 ExprResult Parser::ParseBuiltinPrimaryExpression() {
1756 ExprResult Res;
1757 const IdentifierInfo *BuiltinII = Tok.getIdentifierInfo();
1758
1759 tok::TokenKind T = Tok.getKind();
1760 SourceLocation StartLoc = ConsumeToken(); // Eat the builtin identifier.
1761
1762 // All of these start with an open paren.
1763 if (Tok.isNot(tok::l_paren))
1764 return ExprError(Diag(Tok, diag::err_expected_lparen_after_id)
1765 << BuiltinII);
1766
1767 BalancedDelimiterTracker PT(*this, tok::l_paren);
1768 PT.consumeOpen();
1769
1770 // TODO: Build AST.
1771
1772 switch (T) {
1773 default: llvm_unreachable("Not a builtin primary expression!");
1774 case tok::kw___builtin_va_arg: {
1775 ExprResult Expr(ParseAssignmentExpression());
1776
1777 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren))
1778 Expr = ExprError();
1779
1780 TypeResult Ty = ParseTypeName();
1781
1782 if (Tok.isNot(tok::r_paren)) {
1783 Diag(Tok, diag::err_expected_rparen);
1784 Expr = ExprError();
1785 }
1786
1787 if (Expr.isInvalid() || Ty.isInvalid())
1788 Res = ExprError();
1789 else
1790 Res = Actions.ActOnVAArg(StartLoc, Expr.take(), Ty.get(), ConsumeParen());
1791 break;
1792 }
1793 case tok::kw___builtin_offsetof: {
1794 SourceLocation TypeLoc = Tok.getLocation();
1795 TypeResult Ty = ParseTypeName();
1796 if (Ty.isInvalid()) {
1797 SkipUntil(tok::r_paren);
1798 return ExprError();
1799 }
1800
1801 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren))
1802 return ExprError();
1803
1804 // We must have at least one identifier here.
1805 if (Tok.isNot(tok::identifier)) {
1806 Diag(Tok, diag::err_expected_ident);
1807 SkipUntil(tok::r_paren);
1808 return ExprError();
1809 }
1810
1811 // Keep track of the various subcomponents we see.
1812 SmallVector<Sema::OffsetOfComponent, 4> Comps;
1813
1814 Comps.push_back(Sema::OffsetOfComponent());
1815 Comps.back().isBrackets = false;
1816 Comps.back().U.IdentInfo = Tok.getIdentifierInfo();
1817 Comps.back().LocStart = Comps.back().LocEnd = ConsumeToken();
1818
1819 // FIXME: This loop leaks the index expressions on error.
1820 while (1) {
1821 if (Tok.is(tok::period)) {
1822 // offsetof-member-designator: offsetof-member-designator '.' identifier
1823 Comps.push_back(Sema::OffsetOfComponent());
1824 Comps.back().isBrackets = false;
1825 Comps.back().LocStart = ConsumeToken();
1826
1827 if (Tok.isNot(tok::identifier)) {
1828 Diag(Tok, diag::err_expected_ident);
1829 SkipUntil(tok::r_paren);
1830 return ExprError();
1831 }
1832 Comps.back().U.IdentInfo = Tok.getIdentifierInfo();
1833 Comps.back().LocEnd = ConsumeToken();
1834
1835 } else if (Tok.is(tok::l_square)) {
1836 if (CheckProhibitedCXX11Attribute())
1837 return ExprError();
1838
1839 // offsetof-member-designator: offsetof-member-design '[' expression ']'
1840 Comps.push_back(Sema::OffsetOfComponent());
1841 Comps.back().isBrackets = true;
1842 BalancedDelimiterTracker ST(*this, tok::l_square);
1843 ST.consumeOpen();
1844 Comps.back().LocStart = ST.getOpenLocation();
1845 Res = ParseExpression();
1846 if (Res.isInvalid()) {
1847 SkipUntil(tok::r_paren);
1848 return Res;
1849 }
1850 Comps.back().U.E = Res.release();
1851
1852 ST.consumeClose();
1853 Comps.back().LocEnd = ST.getCloseLocation();
1854 } else {
1855 if (Tok.isNot(tok::r_paren)) {
1856 PT.consumeClose();
1857 Res = ExprError();
1858 } else if (Ty.isInvalid()) {
1859 Res = ExprError();
1860 } else {
1861 PT.consumeClose();
1862 Res = Actions.ActOnBuiltinOffsetOf(getCurScope(), StartLoc, TypeLoc,
1863 Ty.get(), &Comps[0], Comps.size(),
1864 PT.getCloseLocation());
1865 }
1866 break;
1867 }
1868 }
1869 break;
1870 }
1871 case tok::kw___builtin_choose_expr: {
1872 ExprResult Cond(ParseAssignmentExpression());
1873 if (Cond.isInvalid()) {
1874 SkipUntil(tok::r_paren);
1875 return Cond;
1876 }
1877 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren))
1878 return ExprError();
1879
1880 ExprResult Expr1(ParseAssignmentExpression());
1881 if (Expr1.isInvalid()) {
1882 SkipUntil(tok::r_paren);
1883 return Expr1;
1884 }
1885 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren))
1886 return ExprError();
1887
1888 ExprResult Expr2(ParseAssignmentExpression());
1889 if (Expr2.isInvalid()) {
1890 SkipUntil(tok::r_paren);
1891 return Expr2;
1892 }
1893 if (Tok.isNot(tok::r_paren)) {
1894 Diag(Tok, diag::err_expected_rparen);
1895 return ExprError();
1896 }
1897 Res = Actions.ActOnChooseExpr(StartLoc, Cond.take(), Expr1.take(),
1898 Expr2.take(), ConsumeParen());
1899 break;
1900 }
1901 case tok::kw___builtin_astype: {
1902 // The first argument is an expression to be converted, followed by a comma.
1903 ExprResult Expr(ParseAssignmentExpression());
1904 if (Expr.isInvalid()) {
1905 SkipUntil(tok::r_paren);
1906 return ExprError();
1907 }
1908
1909 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",
1910 tok::r_paren))
1911 return ExprError();
1912
1913 // Second argument is the type to bitcast to.
1914 TypeResult DestTy = ParseTypeName();
1915 if (DestTy.isInvalid())
1916 return ExprError();
1917
1918 // Attempt to consume the r-paren.
1919 if (Tok.isNot(tok::r_paren)) {
1920 Diag(Tok, diag::err_expected_rparen);
1921 SkipUntil(tok::r_paren);
1922 return ExprError();
1923 }
1924
1925 Res = Actions.ActOnAsTypeExpr(Expr.take(), DestTy.get(), StartLoc,
1926 ConsumeParen());
1927 break;
1928 }
1929 }
1930
1931 if (Res.isInvalid())
1932 return ExprError();
1933
1934 // These can be followed by postfix-expr pieces because they are
1935 // primary-expressions.
1936 return ParsePostfixExpressionSuffix(Res.take());
1937 }
1938
1939 /// ParseParenExpression - This parses the unit that starts with a '(' token,
1940 /// based on what is allowed by ExprType. The actual thing parsed is returned
1941 /// in ExprType. If stopIfCastExpr is true, it will only return the parsed type,
1942 /// not the parsed cast-expression.
1943 ///
1944 /// \verbatim
1945 /// primary-expression: [C99 6.5.1]
1946 /// '(' expression ')'
1947 /// [GNU] '(' compound-statement ')' (if !ParenExprOnly)
1948 /// postfix-expression: [C99 6.5.2]
1949 /// '(' type-name ')' '{' initializer-list '}'
1950 /// '(' type-name ')' '{' initializer-list ',' '}'
1951 /// cast-expression: [C99 6.5.4]
1952 /// '(' type-name ')' cast-expression
1953 /// [ARC] bridged-cast-expression
1954 ///
1955 /// [ARC] bridged-cast-expression:
1956 /// (__bridge type-name) cast-expression
1957 /// (__bridge_transfer type-name) cast-expression
1958 /// (__bridge_retained type-name) cast-expression
1959 /// \endverbatim
1960 ExprResult
ParseParenExpression(ParenParseOption & ExprType,bool stopIfCastExpr,bool isTypeCast,ParsedType & CastTy,SourceLocation & RParenLoc)1961 Parser::ParseParenExpression(ParenParseOption &ExprType, bool stopIfCastExpr,
1962 bool isTypeCast, ParsedType &CastTy,
1963 SourceLocation &RParenLoc) {
1964 assert(Tok.is(tok::l_paren) && "Not a paren expr!");
1965 BalancedDelimiterTracker T(*this, tok::l_paren);
1966 if (T.consumeOpen())
1967 return ExprError();
1968 SourceLocation OpenLoc = T.getOpenLocation();
1969
1970 ExprResult Result(true);
1971 bool isAmbiguousTypeId;
1972 CastTy = ParsedType();
1973
1974 if (Tok.is(tok::code_completion)) {
1975 Actions.CodeCompleteOrdinaryName(getCurScope(),
1976 ExprType >= CompoundLiteral? Sema::PCC_ParenthesizedExpression
1977 : Sema::PCC_Expression);
1978 cutOffParsing();
1979 return ExprError();
1980 }
1981
1982 // Diagnose use of bridge casts in non-arc mode.
1983 bool BridgeCast = (getLangOpts().ObjC2 &&
1984 (Tok.is(tok::kw___bridge) ||
1985 Tok.is(tok::kw___bridge_transfer) ||
1986 Tok.is(tok::kw___bridge_retained) ||
1987 Tok.is(tok::kw___bridge_retain)));
1988 if (BridgeCast && !getLangOpts().ObjCAutoRefCount) {
1989 StringRef BridgeCastName = Tok.getName();
1990 SourceLocation BridgeKeywordLoc = ConsumeToken();
1991 if (!PP.getSourceManager().isInSystemHeader(BridgeKeywordLoc))
1992 Diag(BridgeKeywordLoc, diag::warn_arc_bridge_cast_nonarc)
1993 << BridgeCastName
1994 << FixItHint::CreateReplacement(BridgeKeywordLoc, "");
1995 BridgeCast = false;
1996 }
1997
1998 // None of these cases should fall through with an invalid Result
1999 // unless they've already reported an error.
2000 if (ExprType >= CompoundStmt && Tok.is(tok::l_brace)) {
2001 Diag(Tok, diag::ext_gnu_statement_expr);
2002 Actions.ActOnStartStmtExpr();
2003
2004 StmtResult Stmt(ParseCompoundStatement(true));
2005 ExprType = CompoundStmt;
2006
2007 // If the substmt parsed correctly, build the AST node.
2008 if (!Stmt.isInvalid()) {
2009 Result = Actions.ActOnStmtExpr(OpenLoc, Stmt.take(), Tok.getLocation());
2010 } else {
2011 Actions.ActOnStmtExprError();
2012 }
2013 } else if (ExprType >= CompoundLiteral && BridgeCast) {
2014 tok::TokenKind tokenKind = Tok.getKind();
2015 SourceLocation BridgeKeywordLoc = ConsumeToken();
2016
2017 // Parse an Objective-C ARC ownership cast expression.
2018 ObjCBridgeCastKind Kind;
2019 if (tokenKind == tok::kw___bridge)
2020 Kind = OBC_Bridge;
2021 else if (tokenKind == tok::kw___bridge_transfer)
2022 Kind = OBC_BridgeTransfer;
2023 else if (tokenKind == tok::kw___bridge_retained)
2024 Kind = OBC_BridgeRetained;
2025 else {
2026 // As a hopefully temporary workaround, allow __bridge_retain as
2027 // a synonym for __bridge_retained, but only in system headers.
2028 assert(tokenKind == tok::kw___bridge_retain);
2029 Kind = OBC_BridgeRetained;
2030 if (!PP.getSourceManager().isInSystemHeader(BridgeKeywordLoc))
2031 Diag(BridgeKeywordLoc, diag::err_arc_bridge_retain)
2032 << FixItHint::CreateReplacement(BridgeKeywordLoc,
2033 "__bridge_retained");
2034 }
2035
2036 TypeResult Ty = ParseTypeName();
2037 T.consumeClose();
2038 RParenLoc = T.getCloseLocation();
2039 ExprResult SubExpr = ParseCastExpression(/*isUnaryExpression=*/false);
2040
2041 if (Ty.isInvalid() || SubExpr.isInvalid())
2042 return ExprError();
2043
2044 return Actions.ActOnObjCBridgedCast(getCurScope(), OpenLoc, Kind,
2045 BridgeKeywordLoc, Ty.get(),
2046 RParenLoc, SubExpr.get());
2047 } else if (ExprType >= CompoundLiteral &&
2048 isTypeIdInParens(isAmbiguousTypeId)) {
2049
2050 // Otherwise, this is a compound literal expression or cast expression.
2051
2052 // In C++, if the type-id is ambiguous we disambiguate based on context.
2053 // If stopIfCastExpr is true the context is a typeof/sizeof/alignof
2054 // in which case we should treat it as type-id.
2055 // if stopIfCastExpr is false, we need to determine the context past the
2056 // parens, so we defer to ParseCXXAmbiguousParenExpression for that.
2057 if (isAmbiguousTypeId && !stopIfCastExpr) {
2058 ExprResult res = ParseCXXAmbiguousParenExpression(ExprType, CastTy, T);
2059 RParenLoc = T.getCloseLocation();
2060 return res;
2061 }
2062
2063 // Parse the type declarator.
2064 DeclSpec DS(AttrFactory);
2065 ParseSpecifierQualifierList(DS);
2066 Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
2067 ParseDeclarator(DeclaratorInfo);
2068
2069 // If our type is followed by an identifier and either ':' or ']', then
2070 // this is probably an Objective-C message send where the leading '[' is
2071 // missing. Recover as if that were the case.
2072 if (!DeclaratorInfo.isInvalidType() && Tok.is(tok::identifier) &&
2073 !InMessageExpression && getLangOpts().ObjC1 &&
2074 (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) {
2075 TypeResult Ty;
2076 {
2077 InMessageExpressionRAIIObject InMessage(*this, false);
2078 Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo);
2079 }
2080 Result = ParseObjCMessageExpressionBody(SourceLocation(),
2081 SourceLocation(),
2082 Ty.get(), 0);
2083 } else {
2084 // Match the ')'.
2085 T.consumeClose();
2086 RParenLoc = T.getCloseLocation();
2087 if (Tok.is(tok::l_brace)) {
2088 ExprType = CompoundLiteral;
2089 TypeResult Ty;
2090 {
2091 InMessageExpressionRAIIObject InMessage(*this, false);
2092 Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo);
2093 }
2094 return ParseCompoundLiteralExpression(Ty.get(), OpenLoc, RParenLoc);
2095 }
2096
2097 if (ExprType == CastExpr) {
2098 // We parsed '(' type-name ')' and the thing after it wasn't a '{'.
2099
2100 if (DeclaratorInfo.isInvalidType())
2101 return ExprError();
2102
2103 // Note that this doesn't parse the subsequent cast-expression, it just
2104 // returns the parsed type to the callee.
2105 if (stopIfCastExpr) {
2106 TypeResult Ty;
2107 {
2108 InMessageExpressionRAIIObject InMessage(*this, false);
2109 Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo);
2110 }
2111 CastTy = Ty.get();
2112 return ExprResult();
2113 }
2114
2115 // Reject the cast of super idiom in ObjC.
2116 if (Tok.is(tok::identifier) && getLangOpts().ObjC1 &&
2117 Tok.getIdentifierInfo() == Ident_super &&
2118 getCurScope()->isInObjcMethodScope() &&
2119 GetLookAheadToken(1).isNot(tok::period)) {
2120 Diag(Tok.getLocation(), diag::err_illegal_super_cast)
2121 << SourceRange(OpenLoc, RParenLoc);
2122 return ExprError();
2123 }
2124
2125 // Parse the cast-expression that follows it next.
2126 // TODO: For cast expression with CastTy.
2127 Result = ParseCastExpression(/*isUnaryExpression=*/false,
2128 /*isAddressOfOperand=*/false,
2129 /*isTypeCast=*/IsTypeCast);
2130 if (!Result.isInvalid()) {
2131 Result = Actions.ActOnCastExpr(getCurScope(), OpenLoc,
2132 DeclaratorInfo, CastTy,
2133 RParenLoc, Result.take());
2134 }
2135 return Result;
2136 }
2137
2138 Diag(Tok, diag::err_expected_lbrace_in_compound_literal);
2139 return ExprError();
2140 }
2141 } else if (isTypeCast) {
2142 // Parse the expression-list.
2143 InMessageExpressionRAIIObject InMessage(*this, false);
2144
2145 ExprVector ArgExprs;
2146 CommaLocsTy CommaLocs;
2147
2148 if (!ParseExpressionList(ArgExprs, CommaLocs)) {
2149 ExprType = SimpleExpr;
2150 Result = Actions.ActOnParenListExpr(OpenLoc, Tok.getLocation(),
2151 ArgExprs);
2152 }
2153 } else {
2154 InMessageExpressionRAIIObject InMessage(*this, false);
2155
2156 Result = ParseExpression(MaybeTypeCast);
2157 ExprType = SimpleExpr;
2158
2159 // Don't build a paren expression unless we actually match a ')'.
2160 if (!Result.isInvalid() && Tok.is(tok::r_paren))
2161 Result = Actions.ActOnParenExpr(OpenLoc, Tok.getLocation(), Result.take());
2162 }
2163
2164 // Match the ')'.
2165 if (Result.isInvalid()) {
2166 SkipUntil(tok::r_paren);
2167 return ExprError();
2168 }
2169
2170 T.consumeClose();
2171 RParenLoc = T.getCloseLocation();
2172 return Result;
2173 }
2174
2175 /// ParseCompoundLiteralExpression - We have parsed the parenthesized type-name
2176 /// and we are at the left brace.
2177 ///
2178 /// \verbatim
2179 /// postfix-expression: [C99 6.5.2]
2180 /// '(' type-name ')' '{' initializer-list '}'
2181 /// '(' type-name ')' '{' initializer-list ',' '}'
2182 /// \endverbatim
2183 ExprResult
ParseCompoundLiteralExpression(ParsedType Ty,SourceLocation LParenLoc,SourceLocation RParenLoc)2184 Parser::ParseCompoundLiteralExpression(ParsedType Ty,
2185 SourceLocation LParenLoc,
2186 SourceLocation RParenLoc) {
2187 assert(Tok.is(tok::l_brace) && "Not a compound literal!");
2188 if (!getLangOpts().C99) // Compound literals don't exist in C90.
2189 Diag(LParenLoc, diag::ext_c99_compound_literal);
2190 ExprResult Result = ParseInitializer();
2191 if (!Result.isInvalid() && Ty)
2192 return Actions.ActOnCompoundLiteral(LParenLoc, Ty, RParenLoc, Result.take());
2193 return Result;
2194 }
2195
2196 /// ParseStringLiteralExpression - This handles the various token types that
2197 /// form string literals, and also handles string concatenation [C99 5.1.1.2,
2198 /// translation phase #6].
2199 ///
2200 /// \verbatim
2201 /// primary-expression: [C99 6.5.1]
2202 /// string-literal
2203 /// \verbatim
ParseStringLiteralExpression(bool AllowUserDefinedLiteral)2204 ExprResult Parser::ParseStringLiteralExpression(bool AllowUserDefinedLiteral) {
2205 assert(isTokenStringLiteral() && "Not a string literal!");
2206
2207 // String concat. Note that keywords like __func__ and __FUNCTION__ are not
2208 // considered to be strings for concatenation purposes.
2209 SmallVector<Token, 4> StringToks;
2210
2211 do {
2212 StringToks.push_back(Tok);
2213 ConsumeStringToken();
2214 } while (isTokenStringLiteral());
2215
2216 // Pass the set of string tokens, ready for concatenation, to the actions.
2217 return Actions.ActOnStringLiteral(&StringToks[0], StringToks.size(),
2218 AllowUserDefinedLiteral ? getCurScope() : 0);
2219 }
2220
2221 /// ParseGenericSelectionExpression - Parse a C11 generic-selection
2222 /// [C11 6.5.1.1].
2223 ///
2224 /// \verbatim
2225 /// generic-selection:
2226 /// _Generic ( assignment-expression , generic-assoc-list )
2227 /// generic-assoc-list:
2228 /// generic-association
2229 /// generic-assoc-list , generic-association
2230 /// generic-association:
2231 /// type-name : assignment-expression
2232 /// default : assignment-expression
2233 /// \endverbatim
ParseGenericSelectionExpression()2234 ExprResult Parser::ParseGenericSelectionExpression() {
2235 assert(Tok.is(tok::kw__Generic) && "_Generic keyword expected");
2236 SourceLocation KeyLoc = ConsumeToken();
2237
2238 if (!getLangOpts().C11)
2239 Diag(KeyLoc, diag::ext_c11_generic_selection);
2240
2241 BalancedDelimiterTracker T(*this, tok::l_paren);
2242 if (T.expectAndConsume(diag::err_expected_lparen))
2243 return ExprError();
2244
2245 ExprResult ControllingExpr;
2246 {
2247 // C11 6.5.1.1p3 "The controlling expression of a generic selection is
2248 // not evaluated."
2249 EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated);
2250 ControllingExpr = ParseAssignmentExpression();
2251 if (ControllingExpr.isInvalid()) {
2252 SkipUntil(tok::r_paren);
2253 return ExprError();
2254 }
2255 }
2256
2257 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "")) {
2258 SkipUntil(tok::r_paren);
2259 return ExprError();
2260 }
2261
2262 SourceLocation DefaultLoc;
2263 TypeVector Types;
2264 ExprVector Exprs;
2265 while (1) {
2266 ParsedType Ty;
2267 if (Tok.is(tok::kw_default)) {
2268 // C11 6.5.1.1p2 "A generic selection shall have no more than one default
2269 // generic association."
2270 if (!DefaultLoc.isInvalid()) {
2271 Diag(Tok, diag::err_duplicate_default_assoc);
2272 Diag(DefaultLoc, diag::note_previous_default_assoc);
2273 SkipUntil(tok::r_paren);
2274 return ExprError();
2275 }
2276 DefaultLoc = ConsumeToken();
2277 Ty = ParsedType();
2278 } else {
2279 ColonProtectionRAIIObject X(*this);
2280 TypeResult TR = ParseTypeName();
2281 if (TR.isInvalid()) {
2282 SkipUntil(tok::r_paren);
2283 return ExprError();
2284 }
2285 Ty = TR.release();
2286 }
2287 Types.push_back(Ty);
2288
2289 if (ExpectAndConsume(tok::colon, diag::err_expected_colon, "")) {
2290 SkipUntil(tok::r_paren);
2291 return ExprError();
2292 }
2293
2294 // FIXME: These expressions should be parsed in a potentially potentially
2295 // evaluated context.
2296 ExprResult ER(ParseAssignmentExpression());
2297 if (ER.isInvalid()) {
2298 SkipUntil(tok::r_paren);
2299 return ExprError();
2300 }
2301 Exprs.push_back(ER.release());
2302
2303 if (Tok.isNot(tok::comma))
2304 break;
2305 ConsumeToken();
2306 }
2307
2308 T.consumeClose();
2309 if (T.getCloseLocation().isInvalid())
2310 return ExprError();
2311
2312 return Actions.ActOnGenericSelectionExpr(KeyLoc, DefaultLoc,
2313 T.getCloseLocation(),
2314 ControllingExpr.release(),
2315 Types, Exprs);
2316 }
2317
2318 /// ParseExpressionList - Used for C/C++ (argument-)expression-list.
2319 ///
2320 /// \verbatim
2321 /// argument-expression-list:
2322 /// assignment-expression
2323 /// argument-expression-list , assignment-expression
2324 ///
2325 /// [C++] expression-list:
2326 /// [C++] assignment-expression
2327 /// [C++] expression-list , assignment-expression
2328 ///
2329 /// [C++0x] expression-list:
2330 /// [C++0x] initializer-list
2331 ///
2332 /// [C++0x] initializer-list
2333 /// [C++0x] initializer-clause ...[opt]
2334 /// [C++0x] initializer-list , initializer-clause ...[opt]
2335 ///
2336 /// [C++0x] initializer-clause:
2337 /// [C++0x] assignment-expression
2338 /// [C++0x] braced-init-list
2339 /// \endverbatim
ParseExpressionList(SmallVectorImpl<Expr * > & Exprs,SmallVectorImpl<SourceLocation> & CommaLocs,void (Sema::* Completer)(Scope * S,Expr * Data,llvm::ArrayRef<Expr * > Args),Expr * Data)2340 bool Parser::ParseExpressionList(SmallVectorImpl<Expr*> &Exprs,
2341 SmallVectorImpl<SourceLocation> &CommaLocs,
2342 void (Sema::*Completer)(Scope *S,
2343 Expr *Data,
2344 llvm::ArrayRef<Expr *> Args),
2345 Expr *Data) {
2346 while (1) {
2347 if (Tok.is(tok::code_completion)) {
2348 if (Completer)
2349 (Actions.*Completer)(getCurScope(), Data, Exprs);
2350 else
2351 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Expression);
2352 cutOffParsing();
2353 return true;
2354 }
2355
2356 ExprResult Expr;
2357 if (getLangOpts().CPlusPlus0x && Tok.is(tok::l_brace)) {
2358 Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists);
2359 Expr = ParseBraceInitializer();
2360 } else
2361 Expr = ParseAssignmentExpression();
2362
2363 if (Tok.is(tok::ellipsis))
2364 Expr = Actions.ActOnPackExpansion(Expr.get(), ConsumeToken());
2365 if (Expr.isInvalid())
2366 return true;
2367
2368 Exprs.push_back(Expr.release());
2369
2370 if (Tok.isNot(tok::comma))
2371 return false;
2372 // Move to the next argument, remember where the comma was.
2373 CommaLocs.push_back(ConsumeToken());
2374 }
2375 }
2376
2377 /// ParseBlockId - Parse a block-id, which roughly looks like int (int x).
2378 ///
2379 /// \verbatim
2380 /// [clang] block-id:
2381 /// [clang] specifier-qualifier-list block-declarator
2382 /// \endverbatim
ParseBlockId(SourceLocation CaretLoc)2383 void Parser::ParseBlockId(SourceLocation CaretLoc) {
2384 if (Tok.is(tok::code_completion)) {
2385 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Type);
2386 return cutOffParsing();
2387 }
2388
2389 // Parse the specifier-qualifier-list piece.
2390 DeclSpec DS(AttrFactory);
2391 ParseSpecifierQualifierList(DS);
2392
2393 // Parse the block-declarator.
2394 Declarator DeclaratorInfo(DS, Declarator::BlockLiteralContext);
2395 ParseDeclarator(DeclaratorInfo);
2396
2397 // We do this for: ^ __attribute__((noreturn)) {, as DS has the attributes.
2398 DeclaratorInfo.takeAttributes(DS.getAttributes(), SourceLocation());
2399
2400 MaybeParseGNUAttributes(DeclaratorInfo);
2401
2402 // Inform sema that we are starting a block.
2403 Actions.ActOnBlockArguments(CaretLoc, DeclaratorInfo, getCurScope());
2404 }
2405
2406 /// ParseBlockLiteralExpression - Parse a block literal, which roughly looks
2407 /// like ^(int x){ return x+1; }
2408 ///
2409 /// \verbatim
2410 /// block-literal:
2411 /// [clang] '^' block-args[opt] compound-statement
2412 /// [clang] '^' block-id compound-statement
2413 /// [clang] block-args:
2414 /// [clang] '(' parameter-list ')'
2415 /// \endverbatim
ParseBlockLiteralExpression()2416 ExprResult Parser::ParseBlockLiteralExpression() {
2417 assert(Tok.is(tok::caret) && "block literal starts with ^");
2418 SourceLocation CaretLoc = ConsumeToken();
2419
2420 PrettyStackTraceLoc CrashInfo(PP.getSourceManager(), CaretLoc,
2421 "block literal parsing");
2422
2423 // Enter a scope to hold everything within the block. This includes the
2424 // argument decls, decls within the compound expression, etc. This also
2425 // allows determining whether a variable reference inside the block is
2426 // within or outside of the block.
2427 ParseScope BlockScope(this, Scope::BlockScope | Scope::FnScope |
2428 Scope::DeclScope);
2429
2430 // Inform sema that we are starting a block.
2431 Actions.ActOnBlockStart(CaretLoc, getCurScope());
2432
2433 // Parse the return type if present.
2434 DeclSpec DS(AttrFactory);
2435 Declarator ParamInfo(DS, Declarator::BlockLiteralContext);
2436 // FIXME: Since the return type isn't actually parsed, it can't be used to
2437 // fill ParamInfo with an initial valid range, so do it manually.
2438 ParamInfo.SetSourceRange(SourceRange(Tok.getLocation(), Tok.getLocation()));
2439
2440 // If this block has arguments, parse them. There is no ambiguity here with
2441 // the expression case, because the expression case requires a parameter list.
2442 if (Tok.is(tok::l_paren)) {
2443 ParseParenDeclarator(ParamInfo);
2444 // Parse the pieces after the identifier as if we had "int(...)".
2445 // SetIdentifier sets the source range end, but in this case we're past
2446 // that location.
2447 SourceLocation Tmp = ParamInfo.getSourceRange().getEnd();
2448 ParamInfo.SetIdentifier(0, CaretLoc);
2449 ParamInfo.SetRangeEnd(Tmp);
2450 if (ParamInfo.isInvalidType()) {
2451 // If there was an error parsing the arguments, they may have
2452 // tried to use ^(x+y) which requires an argument list. Just
2453 // skip the whole block literal.
2454 Actions.ActOnBlockError(CaretLoc, getCurScope());
2455 return ExprError();
2456 }
2457
2458 MaybeParseGNUAttributes(ParamInfo);
2459
2460 // Inform sema that we are starting a block.
2461 Actions.ActOnBlockArguments(CaretLoc, ParamInfo, getCurScope());
2462 } else if (!Tok.is(tok::l_brace)) {
2463 ParseBlockId(CaretLoc);
2464 } else {
2465 // Otherwise, pretend we saw (void).
2466 ParsedAttributes attrs(AttrFactory);
2467 ParamInfo.AddTypeInfo(DeclaratorChunk::getFunction(true, false, false,
2468 SourceLocation(),
2469 0, 0, 0,
2470 true, SourceLocation(),
2471 SourceLocation(),
2472 SourceLocation(),
2473 SourceLocation(),
2474 EST_None,
2475 SourceLocation(),
2476 0, 0, 0, 0,
2477 CaretLoc, CaretLoc,
2478 ParamInfo),
2479 attrs, CaretLoc);
2480
2481 MaybeParseGNUAttributes(ParamInfo);
2482
2483 // Inform sema that we are starting a block.
2484 Actions.ActOnBlockArguments(CaretLoc, ParamInfo, getCurScope());
2485 }
2486
2487
2488 ExprResult Result(true);
2489 if (!Tok.is(tok::l_brace)) {
2490 // Saw something like: ^expr
2491 Diag(Tok, diag::err_expected_expression);
2492 Actions.ActOnBlockError(CaretLoc, getCurScope());
2493 return ExprError();
2494 }
2495
2496 StmtResult Stmt(ParseCompoundStatementBody());
2497 BlockScope.Exit();
2498 if (!Stmt.isInvalid())
2499 Result = Actions.ActOnBlockStmtExpr(CaretLoc, Stmt.take(), getCurScope());
2500 else
2501 Actions.ActOnBlockError(CaretLoc, getCurScope());
2502 return Result;
2503 }
2504
2505 /// ParseObjCBoolLiteral - This handles the objective-c Boolean literals.
2506 ///
2507 /// '__objc_yes'
2508 /// '__objc_no'
ParseObjCBoolLiteral()2509 ExprResult Parser::ParseObjCBoolLiteral() {
2510 tok::TokenKind Kind = Tok.getKind();
2511 return Actions.ActOnObjCBoolLiteral(ConsumeToken(), Kind);
2512 }
2513