clang  8.0.0
ParseStmt.cpp
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1 //===--- ParseStmt.cpp - Statement and Block 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 Statement and Block portions of the Parser
11 // interface.
12 //
13 //===----------------------------------------------------------------------===//
14 
16 #include "clang/Basic/Attributes.h"
18 #include "clang/Parse/LoopHint.h"
19 #include "clang/Parse/Parser.h"
21 #include "clang/Sema/DeclSpec.h"
22 #include "clang/Sema/Scope.h"
24 using namespace clang;
25 
26 //===----------------------------------------------------------------------===//
27 // C99 6.8: Statements and Blocks.
28 //===----------------------------------------------------------------------===//
29 
30 /// Parse a standalone statement (for instance, as the body of an 'if',
31 /// 'while', or 'for').
32 StmtResult Parser::ParseStatement(SourceLocation *TrailingElseLoc,
33  bool AllowOpenMPStandalone) {
34  StmtResult Res;
35 
36  // We may get back a null statement if we found a #pragma. Keep going until
37  // we get an actual statement.
38  do {
39  StmtVector Stmts;
40  Res = ParseStatementOrDeclaration(
41  Stmts, AllowOpenMPStandalone ? ACK_StatementsOpenMPAnyExecutable
42  : ACK_StatementsOpenMPNonStandalone,
43  TrailingElseLoc);
44  } while (!Res.isInvalid() && !Res.get());
45 
46  return Res;
47 }
48 
49 /// ParseStatementOrDeclaration - Read 'statement' or 'declaration'.
50 /// StatementOrDeclaration:
51 /// statement
52 /// declaration
53 ///
54 /// statement:
55 /// labeled-statement
56 /// compound-statement
57 /// expression-statement
58 /// selection-statement
59 /// iteration-statement
60 /// jump-statement
61 /// [C++] declaration-statement
62 /// [C++] try-block
63 /// [MS] seh-try-block
64 /// [OBC] objc-throw-statement
65 /// [OBC] objc-try-catch-statement
66 /// [OBC] objc-synchronized-statement
67 /// [GNU] asm-statement
68 /// [OMP] openmp-construct [TODO]
69 ///
70 /// labeled-statement:
71 /// identifier ':' statement
72 /// 'case' constant-expression ':' statement
73 /// 'default' ':' statement
74 ///
75 /// selection-statement:
76 /// if-statement
77 /// switch-statement
78 ///
79 /// iteration-statement:
80 /// while-statement
81 /// do-statement
82 /// for-statement
83 ///
84 /// expression-statement:
85 /// expression[opt] ';'
86 ///
87 /// jump-statement:
88 /// 'goto' identifier ';'
89 /// 'continue' ';'
90 /// 'break' ';'
91 /// 'return' expression[opt] ';'
92 /// [GNU] 'goto' '*' expression ';'
93 ///
94 /// [OBC] objc-throw-statement:
95 /// [OBC] '@' 'throw' expression ';'
96 /// [OBC] '@' 'throw' ';'
97 ///
99 Parser::ParseStatementOrDeclaration(StmtVector &Stmts,
100  AllowedConstructsKind Allowed,
101  SourceLocation *TrailingElseLoc) {
102 
103  ParenBraceBracketBalancer BalancerRAIIObj(*this);
104 
105  ParsedAttributesWithRange Attrs(AttrFactory);
106  MaybeParseCXX11Attributes(Attrs, nullptr, /*MightBeObjCMessageSend*/ true);
107  if (!MaybeParseOpenCLUnrollHintAttribute(Attrs))
108  return StmtError();
109 
110  StmtResult Res = ParseStatementOrDeclarationAfterAttributes(
111  Stmts, Allowed, TrailingElseLoc, Attrs);
112 
113  assert((Attrs.empty() || Res.isInvalid() || Res.isUsable()) &&
114  "attributes on empty statement");
115 
116  if (Attrs.empty() || Res.isInvalid())
117  return Res;
118 
119  return Actions.ProcessStmtAttributes(Res.get(), Attrs, Attrs.Range);
120 }
121 
122 namespace {
123 class StatementFilterCCC : public CorrectionCandidateCallback {
124 public:
125  StatementFilterCCC(Token nextTok) : NextToken(nextTok) {
126  WantTypeSpecifiers = nextTok.isOneOf(tok::l_paren, tok::less, tok::l_square,
127  tok::identifier, tok::star, tok::amp);
128  WantExpressionKeywords =
129  nextTok.isOneOf(tok::l_paren, tok::identifier, tok::arrow, tok::period);
130  WantRemainingKeywords =
131  nextTok.isOneOf(tok::l_paren, tok::semi, tok::identifier, tok::l_brace);
132  WantCXXNamedCasts = false;
133  }
134 
135  bool ValidateCandidate(const TypoCorrection &candidate) override {
136  if (FieldDecl *FD = candidate.getCorrectionDeclAs<FieldDecl>())
137  return !candidate.getCorrectionSpecifier() || isa<ObjCIvarDecl>(FD);
138  if (NextToken.is(tok::equal))
139  return candidate.getCorrectionDeclAs<VarDecl>();
140  if (NextToken.is(tok::period) &&
141  candidate.getCorrectionDeclAs<NamespaceDecl>())
142  return false;
144  }
145 
146 private:
148 };
149 }
150 
152 Parser::ParseStatementOrDeclarationAfterAttributes(StmtVector &Stmts,
153  AllowedConstructsKind Allowed, SourceLocation *TrailingElseLoc,
154  ParsedAttributesWithRange &Attrs) {
155  const char *SemiError = nullptr;
156  StmtResult Res;
157 
158  // Cases in this switch statement should fall through if the parser expects
159  // the token to end in a semicolon (in which case SemiError should be set),
160  // or they directly 'return;' if not.
161 Retry:
162  tok::TokenKind Kind = Tok.getKind();
163  SourceLocation AtLoc;
164  switch (Kind) {
165  case tok::at: // May be a @try or @throw statement
166  {
167  ProhibitAttributes(Attrs); // TODO: is it correct?
168  AtLoc = ConsumeToken(); // consume @
169  return ParseObjCAtStatement(AtLoc);
170  }
171 
172  case tok::code_completion:
173  Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Statement);
174  cutOffParsing();
175  return StmtError();
176 
177  case tok::identifier: {
178  Token Next = NextToken();
179  if (Next.is(tok::colon)) { // C99 6.8.1: labeled-statement
180  // identifier ':' statement
181  return ParseLabeledStatement(Attrs);
182  }
183 
184  // Look up the identifier, and typo-correct it to a keyword if it's not
185  // found.
186  if (Next.isNot(tok::coloncolon)) {
187  // Try to limit which sets of keywords should be included in typo
188  // correction based on what the next token is.
189  if (TryAnnotateName(/*IsAddressOfOperand*/ false,
190  llvm::make_unique<StatementFilterCCC>(Next)) ==
191  ANK_Error) {
192  // Handle errors here by skipping up to the next semicolon or '}', and
193  // eat the semicolon if that's what stopped us.
194  SkipUntil(tok::r_brace, StopAtSemi | StopBeforeMatch);
195  if (Tok.is(tok::semi))
196  ConsumeToken();
197  return StmtError();
198  }
199 
200  // If the identifier was typo-corrected, try again.
201  if (Tok.isNot(tok::identifier))
202  goto Retry;
203  }
204 
205  // Fall through
206  LLVM_FALLTHROUGH;
207  }
208 
209  default: {
210  if ((getLangOpts().CPlusPlus || getLangOpts().MicrosoftExt ||
211  Allowed == ACK_Any) &&
212  isDeclarationStatement()) {
213  SourceLocation DeclStart = Tok.getLocation(), DeclEnd;
215  DeclEnd, Attrs);
216  return Actions.ActOnDeclStmt(Decl, DeclStart, DeclEnd);
217  }
218 
219  if (Tok.is(tok::r_brace)) {
220  Diag(Tok, diag::err_expected_statement);
221  return StmtError();
222  }
223 
224  return ParseExprStatement();
225  }
226 
227  case tok::kw_case: // C99 6.8.1: labeled-statement
228  return ParseCaseStatement();
229  case tok::kw_default: // C99 6.8.1: labeled-statement
230  return ParseDefaultStatement();
231 
232  case tok::l_brace: // C99 6.8.2: compound-statement
233  return ParseCompoundStatement();
234  case tok::semi: { // C99 6.8.3p3: expression[opt] ';'
235  bool HasLeadingEmptyMacro = Tok.hasLeadingEmptyMacro();
236  return Actions.ActOnNullStmt(ConsumeToken(), HasLeadingEmptyMacro);
237  }
238 
239  case tok::kw_if: // C99 6.8.4.1: if-statement
240  return ParseIfStatement(TrailingElseLoc);
241  case tok::kw_switch: // C99 6.8.4.2: switch-statement
242  return ParseSwitchStatement(TrailingElseLoc);
243 
244  case tok::kw_while: // C99 6.8.5.1: while-statement
245  return ParseWhileStatement(TrailingElseLoc);
246  case tok::kw_do: // C99 6.8.5.2: do-statement
247  Res = ParseDoStatement();
248  SemiError = "do/while";
249  break;
250  case tok::kw_for: // C99 6.8.5.3: for-statement
251  return ParseForStatement(TrailingElseLoc);
252 
253  case tok::kw_goto: // C99 6.8.6.1: goto-statement
254  Res = ParseGotoStatement();
255  SemiError = "goto";
256  break;
257  case tok::kw_continue: // C99 6.8.6.2: continue-statement
258  Res = ParseContinueStatement();
259  SemiError = "continue";
260  break;
261  case tok::kw_break: // C99 6.8.6.3: break-statement
262  Res = ParseBreakStatement();
263  SemiError = "break";
264  break;
265  case tok::kw_return: // C99 6.8.6.4: return-statement
266  Res = ParseReturnStatement();
267  SemiError = "return";
268  break;
269  case tok::kw_co_return: // C++ Coroutines: co_return statement
270  Res = ParseReturnStatement();
271  SemiError = "co_return";
272  break;
273 
274  case tok::kw_asm: {
275  ProhibitAttributes(Attrs);
276  bool msAsm = false;
277  Res = ParseAsmStatement(msAsm);
278  Res = Actions.ActOnFinishFullStmt(Res.get());
279  if (msAsm) return Res;
280  SemiError = "asm";
281  break;
282  }
283 
284  case tok::kw___if_exists:
285  case tok::kw___if_not_exists:
286  ProhibitAttributes(Attrs);
287  ParseMicrosoftIfExistsStatement(Stmts);
288  // An __if_exists block is like a compound statement, but it doesn't create
289  // a new scope.
290  return StmtEmpty();
291 
292  case tok::kw_try: // C++ 15: try-block
293  return ParseCXXTryBlock();
294 
295  case tok::kw___try:
296  ProhibitAttributes(Attrs); // TODO: is it correct?
297  return ParseSEHTryBlock();
298 
299  case tok::kw___leave:
300  Res = ParseSEHLeaveStatement();
301  SemiError = "__leave";
302  break;
303 
304  case tok::annot_pragma_vis:
305  ProhibitAttributes(Attrs);
306  HandlePragmaVisibility();
307  return StmtEmpty();
308 
309  case tok::annot_pragma_pack:
310  ProhibitAttributes(Attrs);
311  HandlePragmaPack();
312  return StmtEmpty();
313 
314  case tok::annot_pragma_msstruct:
315  ProhibitAttributes(Attrs);
316  HandlePragmaMSStruct();
317  return StmtEmpty();
318 
319  case tok::annot_pragma_align:
320  ProhibitAttributes(Attrs);
321  HandlePragmaAlign();
322  return StmtEmpty();
323 
324  case tok::annot_pragma_weak:
325  ProhibitAttributes(Attrs);
326  HandlePragmaWeak();
327  return StmtEmpty();
328 
329  case tok::annot_pragma_weakalias:
330  ProhibitAttributes(Attrs);
331  HandlePragmaWeakAlias();
332  return StmtEmpty();
333 
334  case tok::annot_pragma_redefine_extname:
335  ProhibitAttributes(Attrs);
336  HandlePragmaRedefineExtname();
337  return StmtEmpty();
338 
339  case tok::annot_pragma_fp_contract:
340  ProhibitAttributes(Attrs);
341  Diag(Tok, diag::err_pragma_fp_contract_scope);
342  ConsumeAnnotationToken();
343  return StmtError();
344 
345  case tok::annot_pragma_fp:
346  ProhibitAttributes(Attrs);
347  Diag(Tok, diag::err_pragma_fp_scope);
348  ConsumeAnnotationToken();
349  return StmtError();
350 
351  case tok::annot_pragma_fenv_access:
352  ProhibitAttributes(Attrs);
353  HandlePragmaFEnvAccess();
354  return StmtEmpty();
355 
356  case tok::annot_pragma_opencl_extension:
357  ProhibitAttributes(Attrs);
358  HandlePragmaOpenCLExtension();
359  return StmtEmpty();
360 
361  case tok::annot_pragma_captured:
362  ProhibitAttributes(Attrs);
363  return HandlePragmaCaptured();
364 
365  case tok::annot_pragma_openmp:
366  ProhibitAttributes(Attrs);
367  return ParseOpenMPDeclarativeOrExecutableDirective(Allowed);
368 
369  case tok::annot_pragma_ms_pointers_to_members:
370  ProhibitAttributes(Attrs);
371  HandlePragmaMSPointersToMembers();
372  return StmtEmpty();
373 
374  case tok::annot_pragma_ms_pragma:
375  ProhibitAttributes(Attrs);
376  HandlePragmaMSPragma();
377  return StmtEmpty();
378 
379  case tok::annot_pragma_ms_vtordisp:
380  ProhibitAttributes(Attrs);
381  HandlePragmaMSVtorDisp();
382  return StmtEmpty();
383 
384  case tok::annot_pragma_loop_hint:
385  ProhibitAttributes(Attrs);
386  return ParsePragmaLoopHint(Stmts, Allowed, TrailingElseLoc, Attrs);
387 
388  case tok::annot_pragma_dump:
389  HandlePragmaDump();
390  return StmtEmpty();
391 
392  case tok::annot_pragma_attribute:
393  HandlePragmaAttribute();
394  return StmtEmpty();
395  }
396 
397  // If we reached this code, the statement must end in a semicolon.
398  if (!TryConsumeToken(tok::semi) && !Res.isInvalid()) {
399  // If the result was valid, then we do want to diagnose this. Use
400  // ExpectAndConsume to emit the diagnostic, even though we know it won't
401  // succeed.
402  ExpectAndConsume(tok::semi, diag::err_expected_semi_after_stmt, SemiError);
403  // Skip until we see a } or ;, but don't eat it.
404  SkipUntil(tok::r_brace, StopAtSemi | StopBeforeMatch);
405  }
406 
407  return Res;
408 }
409 
410 /// Parse an expression statement.
411 StmtResult Parser::ParseExprStatement() {
412  // If a case keyword is missing, this is where it should be inserted.
413  Token OldToken = Tok;
414 
415  ExprStatementTokLoc = Tok.getLocation();
416 
417  // expression[opt] ';'
419  if (Expr.isInvalid()) {
420  // If the expression is invalid, skip ahead to the next semicolon or '}'.
421  // Not doing this opens us up to the possibility of infinite loops if
422  // ParseExpression does not consume any tokens.
423  SkipUntil(tok::r_brace, StopAtSemi | StopBeforeMatch);
424  if (Tok.is(tok::semi))
425  ConsumeToken();
426  return Actions.ActOnExprStmtError();
427  }
428 
429  if (Tok.is(tok::colon) && getCurScope()->isSwitchScope() &&
430  Actions.CheckCaseExpression(Expr.get())) {
431  // If a constant expression is followed by a colon inside a switch block,
432  // suggest a missing case keyword.
433  Diag(OldToken, diag::err_expected_case_before_expression)
434  << FixItHint::CreateInsertion(OldToken.getLocation(), "case ");
435 
436  // Recover parsing as a case statement.
437  return ParseCaseStatement(/*MissingCase=*/true, Expr);
438  }
439 
440  // Otherwise, eat the semicolon.
441  ExpectAndConsumeSemi(diag::err_expected_semi_after_expr);
442  return Actions.ActOnExprStmt(Expr, isExprValueDiscarded());
443 }
444 
445 /// ParseSEHTryBlockCommon
446 ///
447 /// seh-try-block:
448 /// '__try' compound-statement seh-handler
449 ///
450 /// seh-handler:
451 /// seh-except-block
452 /// seh-finally-block
453 ///
454 StmtResult Parser::ParseSEHTryBlock() {
455  assert(Tok.is(tok::kw___try) && "Expected '__try'");
456  SourceLocation TryLoc = ConsumeToken();
457 
458  if (Tok.isNot(tok::l_brace))
459  return StmtError(Diag(Tok, diag::err_expected) << tok::l_brace);
460 
461  StmtResult TryBlock(ParseCompoundStatement(
462  /*isStmtExpr=*/false,
464  if (TryBlock.isInvalid())
465  return TryBlock;
466 
467  StmtResult Handler;
468  if (Tok.is(tok::identifier) &&
469  Tok.getIdentifierInfo() == getSEHExceptKeyword()) {
471  Handler = ParseSEHExceptBlock(Loc);
472  } else if (Tok.is(tok::kw___finally)) {
474  Handler = ParseSEHFinallyBlock(Loc);
475  } else {
476  return StmtError(Diag(Tok, diag::err_seh_expected_handler));
477  }
478 
479  if(Handler.isInvalid())
480  return Handler;
481 
482  return Actions.ActOnSEHTryBlock(false /* IsCXXTry */,
483  TryLoc,
484  TryBlock.get(),
485  Handler.get());
486 }
487 
488 /// ParseSEHExceptBlock - Handle __except
489 ///
490 /// seh-except-block:
491 /// '__except' '(' seh-filter-expression ')' compound-statement
492 ///
493 StmtResult Parser::ParseSEHExceptBlock(SourceLocation ExceptLoc) {
494  PoisonIdentifierRAIIObject raii(Ident__exception_code, false),
495  raii2(Ident___exception_code, false),
496  raii3(Ident_GetExceptionCode, false);
497 
498  if (ExpectAndConsume(tok::l_paren))
499  return StmtError();
500 
501  ParseScope ExpectScope(this, Scope::DeclScope | Scope::ControlScope |
503 
504  if (getLangOpts().Borland) {
505  Ident__exception_info->setIsPoisoned(false);
506  Ident___exception_info->setIsPoisoned(false);
507  Ident_GetExceptionInfo->setIsPoisoned(false);
508  }
509 
510  ExprResult FilterExpr;
511  {
512  ParseScopeFlags FilterScope(this, getCurScope()->getFlags() |
514  FilterExpr = Actions.CorrectDelayedTyposInExpr(ParseExpression());
515  }
516 
517  if (getLangOpts().Borland) {
518  Ident__exception_info->setIsPoisoned(true);
519  Ident___exception_info->setIsPoisoned(true);
520  Ident_GetExceptionInfo->setIsPoisoned(true);
521  }
522 
523  if(FilterExpr.isInvalid())
524  return StmtError();
525 
526  if (ExpectAndConsume(tok::r_paren))
527  return StmtError();
528 
529  if (Tok.isNot(tok::l_brace))
530  return StmtError(Diag(Tok, diag::err_expected) << tok::l_brace);
531 
532  StmtResult Block(ParseCompoundStatement());
533 
534  if(Block.isInvalid())
535  return Block;
536 
537  return Actions.ActOnSEHExceptBlock(ExceptLoc, FilterExpr.get(), Block.get());
538 }
539 
540 /// ParseSEHFinallyBlock - Handle __finally
541 ///
542 /// seh-finally-block:
543 /// '__finally' compound-statement
544 ///
545 StmtResult Parser::ParseSEHFinallyBlock(SourceLocation FinallyLoc) {
546  PoisonIdentifierRAIIObject raii(Ident__abnormal_termination, false),
547  raii2(Ident___abnormal_termination, false),
548  raii3(Ident_AbnormalTermination, false);
549 
550  if (Tok.isNot(tok::l_brace))
551  return StmtError(Diag(Tok, diag::err_expected) << tok::l_brace);
552 
553  ParseScope FinallyScope(this, 0);
554  Actions.ActOnStartSEHFinallyBlock();
555 
556  StmtResult Block(ParseCompoundStatement());
557  if(Block.isInvalid()) {
558  Actions.ActOnAbortSEHFinallyBlock();
559  return Block;
560  }
561 
562  return Actions.ActOnFinishSEHFinallyBlock(FinallyLoc, Block.get());
563 }
564 
565 /// Handle __leave
566 ///
567 /// seh-leave-statement:
568 /// '__leave' ';'
569 ///
570 StmtResult Parser::ParseSEHLeaveStatement() {
571  SourceLocation LeaveLoc = ConsumeToken(); // eat the '__leave'.
572  return Actions.ActOnSEHLeaveStmt(LeaveLoc, getCurScope());
573 }
574 
575 /// ParseLabeledStatement - We have an identifier and a ':' after it.
576 ///
577 /// labeled-statement:
578 /// identifier ':' statement
579 /// [GNU] identifier ':' attributes[opt] statement
580 ///
581 StmtResult Parser::ParseLabeledStatement(ParsedAttributesWithRange &attrs) {
582  assert(Tok.is(tok::identifier) && Tok.getIdentifierInfo() &&
583  "Not an identifier!");
584 
585  Token IdentTok = Tok; // Save the whole token.
586  ConsumeToken(); // eat the identifier.
587 
588  assert(Tok.is(tok::colon) && "Not a label!");
589 
590  // identifier ':' statement
592 
593  // Read label attributes, if present.
594  StmtResult SubStmt;
595  if (Tok.is(tok::kw___attribute)) {
596  ParsedAttributesWithRange TempAttrs(AttrFactory);
597  ParseGNUAttributes(TempAttrs);
598 
599  // In C++, GNU attributes only apply to the label if they are followed by a
600  // semicolon, to disambiguate label attributes from attributes on a labeled
601  // declaration.
602  //
603  // This doesn't quite match what GCC does; if the attribute list is empty
604  // and followed by a semicolon, GCC will reject (it appears to parse the
605  // attributes as part of a statement in that case). That looks like a bug.
606  if (!getLangOpts().CPlusPlus || Tok.is(tok::semi))
607  attrs.takeAllFrom(TempAttrs);
608  else if (isDeclarationStatement()) {
609  StmtVector Stmts;
610  // FIXME: We should do this whether or not we have a declaration
611  // statement, but that doesn't work correctly (because ProhibitAttributes
612  // can't handle GNU attributes), so only call it in the one case where
613  // GNU attributes are allowed.
614  SubStmt = ParseStatementOrDeclarationAfterAttributes(
615  Stmts, /*Allowed=*/ACK_StatementsOpenMPNonStandalone, nullptr,
616  TempAttrs);
617  if (!TempAttrs.empty() && !SubStmt.isInvalid())
618  SubStmt = Actions.ProcessStmtAttributes(SubStmt.get(), TempAttrs,
619  TempAttrs.Range);
620  } else {
621  Diag(Tok, diag::err_expected_after) << "__attribute__" << tok::semi;
622  }
623  }
624 
625  // If we've not parsed a statement yet, parse one now.
626  if (!SubStmt.isInvalid() && !SubStmt.isUsable())
627  SubStmt = ParseStatement();
628 
629  // Broken substmt shouldn't prevent the label from being added to the AST.
630  if (SubStmt.isInvalid())
631  SubStmt = Actions.ActOnNullStmt(ColonLoc);
632 
633  LabelDecl *LD = Actions.LookupOrCreateLabel(IdentTok.getIdentifierInfo(),
634  IdentTok.getLocation());
635  Actions.ProcessDeclAttributeList(Actions.CurScope, LD, attrs);
636  attrs.clear();
637 
638  return Actions.ActOnLabelStmt(IdentTok.getLocation(), LD, ColonLoc,
639  SubStmt.get());
640 }
641 
642 /// ParseCaseStatement
643 /// labeled-statement:
644 /// 'case' constant-expression ':' statement
645 /// [GNU] 'case' constant-expression '...' constant-expression ':' statement
646 ///
647 StmtResult Parser::ParseCaseStatement(bool MissingCase, ExprResult Expr) {
648  assert((MissingCase || Tok.is(tok::kw_case)) && "Not a case stmt!");
649 
650  // It is very very common for code to contain many case statements recursively
651  // nested, as in (but usually without indentation):
652  // case 1:
653  // case 2:
654  // case 3:
655  // case 4:
656  // case 5: etc.
657  //
658  // Parsing this naively works, but is both inefficient and can cause us to run
659  // out of stack space in our recursive descent parser. As a special case,
660  // flatten this recursion into an iterative loop. This is complex and gross,
661  // but all the grossness is constrained to ParseCaseStatement (and some
662  // weirdness in the actions), so this is just local grossness :).
663 
664  // TopLevelCase - This is the highest level we have parsed. 'case 1' in the
665  // example above.
666  StmtResult TopLevelCase(true);
667 
668  // DeepestParsedCaseStmt - This is the deepest statement we have parsed, which
669  // gets updated each time a new case is parsed, and whose body is unset so
670  // far. When parsing 'case 4', this is the 'case 3' node.
671  Stmt *DeepestParsedCaseStmt = nullptr;
672 
673  // While we have case statements, eat and stack them.
675  do {
676  SourceLocation CaseLoc = MissingCase ? Expr.get()->getExprLoc() :
677  ConsumeToken(); // eat the 'case'.
678  ColonLoc = SourceLocation();
679 
680  if (Tok.is(tok::code_completion)) {
681  Actions.CodeCompleteCase(getCurScope());
682  cutOffParsing();
683  return StmtError();
684  }
685 
686  /// We don't want to treat 'case x : y' as a potential typo for 'case x::y'.
687  /// Disable this form of error recovery while we're parsing the case
688  /// expression.
689  ColonProtectionRAIIObject ColonProtection(*this);
690 
691  ExprResult LHS;
692  if (!MissingCase) {
693  LHS = ParseCaseExpression(CaseLoc);
694  if (LHS.isInvalid()) {
695  // If constant-expression is parsed unsuccessfully, recover by skipping
696  // current case statement (moving to the colon that ends it).
697  if (!SkipUntil(tok::colon, tok::r_brace, StopAtSemi | StopBeforeMatch))
698  return StmtError();
699  }
700  } else {
701  LHS = Expr;
702  MissingCase = false;
703  }
704 
705  // GNU case range extension.
706  SourceLocation DotDotDotLoc;
707  ExprResult RHS;
708  if (TryConsumeToken(tok::ellipsis, DotDotDotLoc)) {
709  Diag(DotDotDotLoc, diag::ext_gnu_case_range);
710  RHS = ParseCaseExpression(CaseLoc);
711  if (RHS.isInvalid()) {
712  if (!SkipUntil(tok::colon, tok::r_brace, StopAtSemi | StopBeforeMatch))
713  return StmtError();
714  }
715  }
716 
717  ColonProtection.restore();
718 
719  if (TryConsumeToken(tok::colon, ColonLoc)) {
720  } else if (TryConsumeToken(tok::semi, ColonLoc) ||
721  TryConsumeToken(tok::coloncolon, ColonLoc)) {
722  // Treat "case blah;" or "case blah::" as a typo for "case blah:".
723  Diag(ColonLoc, diag::err_expected_after)
724  << "'case'" << tok::colon
725  << FixItHint::CreateReplacement(ColonLoc, ":");
726  } else {
727  SourceLocation ExpectedLoc = PP.getLocForEndOfToken(PrevTokLocation);
728  Diag(ExpectedLoc, diag::err_expected_after)
729  << "'case'" << tok::colon
730  << FixItHint::CreateInsertion(ExpectedLoc, ":");
731  ColonLoc = ExpectedLoc;
732  }
733 
734  StmtResult Case =
735  Actions.ActOnCaseStmt(CaseLoc, LHS, DotDotDotLoc, RHS, ColonLoc);
736 
737  // If we had a sema error parsing this case, then just ignore it and
738  // continue parsing the sub-stmt.
739  if (Case.isInvalid()) {
740  if (TopLevelCase.isInvalid()) // No parsed case stmts.
741  return ParseStatement(/*TrailingElseLoc=*/nullptr,
742  /*AllowOpenMPStandalone=*/true);
743  // Otherwise, just don't add it as a nested case.
744  } else {
745  // If this is the first case statement we parsed, it becomes TopLevelCase.
746  // Otherwise we link it into the current chain.
747  Stmt *NextDeepest = Case.get();
748  if (TopLevelCase.isInvalid())
749  TopLevelCase = Case;
750  else
751  Actions.ActOnCaseStmtBody(DeepestParsedCaseStmt, Case.get());
752  DeepestParsedCaseStmt = NextDeepest;
753  }
754 
755  // Handle all case statements.
756  } while (Tok.is(tok::kw_case));
757 
758  // If we found a non-case statement, start by parsing it.
759  StmtResult SubStmt;
760 
761  if (Tok.isNot(tok::r_brace)) {
762  SubStmt = ParseStatement(/*TrailingElseLoc=*/nullptr,
763  /*AllowOpenMPStandalone=*/true);
764  } else {
765  // Nicely diagnose the common error "switch (X) { case 4: }", which is
766  // not valid. If ColonLoc doesn't point to a valid text location, there was
767  // another parsing error, so avoid producing extra diagnostics.
768  if (ColonLoc.isValid()) {
769  SourceLocation AfterColonLoc = PP.getLocForEndOfToken(ColonLoc);
770  Diag(AfterColonLoc, diag::err_label_end_of_compound_statement)
771  << FixItHint::CreateInsertion(AfterColonLoc, " ;");
772  }
773  SubStmt = StmtError();
774  }
775 
776  // Install the body into the most deeply-nested case.
777  if (DeepestParsedCaseStmt) {
778  // Broken sub-stmt shouldn't prevent forming the case statement properly.
779  if (SubStmt.isInvalid())
780  SubStmt = Actions.ActOnNullStmt(SourceLocation());
781  Actions.ActOnCaseStmtBody(DeepestParsedCaseStmt, SubStmt.get());
782  }
783 
784  // Return the top level parsed statement tree.
785  return TopLevelCase;
786 }
787 
788 /// ParseDefaultStatement
789 /// labeled-statement:
790 /// 'default' ':' statement
791 /// Note that this does not parse the 'statement' at the end.
792 ///
793 StmtResult Parser::ParseDefaultStatement() {
794  assert(Tok.is(tok::kw_default) && "Not a default stmt!");
795  SourceLocation DefaultLoc = ConsumeToken(); // eat the 'default'.
796 
798  if (TryConsumeToken(tok::colon, ColonLoc)) {
799  } else if (TryConsumeToken(tok::semi, ColonLoc)) {
800  // Treat "default;" as a typo for "default:".
801  Diag(ColonLoc, diag::err_expected_after)
802  << "'default'" << tok::colon
803  << FixItHint::CreateReplacement(ColonLoc, ":");
804  } else {
805  SourceLocation ExpectedLoc = PP.getLocForEndOfToken(PrevTokLocation);
806  Diag(ExpectedLoc, diag::err_expected_after)
807  << "'default'" << tok::colon
808  << FixItHint::CreateInsertion(ExpectedLoc, ":");
809  ColonLoc = ExpectedLoc;
810  }
811 
812  StmtResult SubStmt;
813 
814  if (Tok.isNot(tok::r_brace)) {
815  SubStmt = ParseStatement(/*TrailingElseLoc=*/nullptr,
816  /*AllowOpenMPStandalone=*/true);
817  } else {
818  // Diagnose the common error "switch (X) {... default: }", which is
819  // not valid.
820  SourceLocation AfterColonLoc = PP.getLocForEndOfToken(ColonLoc);
821  Diag(AfterColonLoc, diag::err_label_end_of_compound_statement)
822  << FixItHint::CreateInsertion(AfterColonLoc, " ;");
823  SubStmt = true;
824  }
825 
826  // Broken sub-stmt shouldn't prevent forming the case statement properly.
827  if (SubStmt.isInvalid())
828  SubStmt = Actions.ActOnNullStmt(ColonLoc);
829 
830  return Actions.ActOnDefaultStmt(DefaultLoc, ColonLoc,
831  SubStmt.get(), getCurScope());
832 }
833 
834 StmtResult Parser::ParseCompoundStatement(bool isStmtExpr) {
835  return ParseCompoundStatement(isStmtExpr,
837 }
838 
839 /// ParseCompoundStatement - Parse a "{}" block.
840 ///
841 /// compound-statement: [C99 6.8.2]
842 /// { block-item-list[opt] }
843 /// [GNU] { label-declarations block-item-list } [TODO]
844 ///
845 /// block-item-list:
846 /// block-item
847 /// block-item-list block-item
848 ///
849 /// block-item:
850 /// declaration
851 /// [GNU] '__extension__' declaration
852 /// statement
853 ///
854 /// [GNU] label-declarations:
855 /// [GNU] label-declaration
856 /// [GNU] label-declarations label-declaration
857 ///
858 /// [GNU] label-declaration:
859 /// [GNU] '__label__' identifier-list ';'
860 ///
861 StmtResult Parser::ParseCompoundStatement(bool isStmtExpr,
862  unsigned ScopeFlags) {
863  assert(Tok.is(tok::l_brace) && "Not a compount stmt!");
864 
865  // Enter a scope to hold everything within the compound stmt. Compound
866  // statements can always hold declarations.
867  ParseScope CompoundScope(this, ScopeFlags);
868 
869  // Parse the statements in the body.
870  return ParseCompoundStatementBody(isStmtExpr);
871 }
872 
873 /// Parse any pragmas at the start of the compound expression. We handle these
874 /// separately since some pragmas (FP_CONTRACT) must appear before any C
875 /// statement in the compound, but may be intermingled with other pragmas.
876 void Parser::ParseCompoundStatementLeadingPragmas() {
877  bool checkForPragmas = true;
878  while (checkForPragmas) {
879  switch (Tok.getKind()) {
880  case tok::annot_pragma_vis:
881  HandlePragmaVisibility();
882  break;
883  case tok::annot_pragma_pack:
884  HandlePragmaPack();
885  break;
886  case tok::annot_pragma_msstruct:
887  HandlePragmaMSStruct();
888  break;
889  case tok::annot_pragma_align:
890  HandlePragmaAlign();
891  break;
892  case tok::annot_pragma_weak:
893  HandlePragmaWeak();
894  break;
895  case tok::annot_pragma_weakalias:
896  HandlePragmaWeakAlias();
897  break;
898  case tok::annot_pragma_redefine_extname:
899  HandlePragmaRedefineExtname();
900  break;
901  case tok::annot_pragma_opencl_extension:
902  HandlePragmaOpenCLExtension();
903  break;
904  case tok::annot_pragma_fp_contract:
905  HandlePragmaFPContract();
906  break;
907  case tok::annot_pragma_fp:
908  HandlePragmaFP();
909  break;
910  case tok::annot_pragma_fenv_access:
911  HandlePragmaFEnvAccess();
912  break;
913  case tok::annot_pragma_ms_pointers_to_members:
914  HandlePragmaMSPointersToMembers();
915  break;
916  case tok::annot_pragma_ms_pragma:
917  HandlePragmaMSPragma();
918  break;
919  case tok::annot_pragma_ms_vtordisp:
920  HandlePragmaMSVtorDisp();
921  break;
922  case tok::annot_pragma_dump:
923  HandlePragmaDump();
924  break;
925  default:
926  checkForPragmas = false;
927  break;
928  }
929  }
930 
931 }
932 
933 /// Consume any extra semi-colons resulting in null statements,
934 /// returning true if any tok::semi were consumed.
935 bool Parser::ConsumeNullStmt(StmtVector &Stmts) {
936  if (!Tok.is(tok::semi))
937  return false;
938 
939  SourceLocation StartLoc = Tok.getLocation();
940  SourceLocation EndLoc;
941 
942  while (Tok.is(tok::semi) && !Tok.hasLeadingEmptyMacro() &&
943  Tok.getLocation().isValid() && !Tok.getLocation().isMacroID()) {
944  EndLoc = Tok.getLocation();
945 
946  // Don't just ConsumeToken() this tok::semi, do store it in AST.
947  StmtResult R = ParseStatementOrDeclaration(Stmts, ACK_Any);
948  if (R.isUsable())
949  Stmts.push_back(R.get());
950  }
951 
952  // Did not consume any extra semi.
953  if (EndLoc.isInvalid())
954  return false;
955 
956  Diag(StartLoc, diag::warn_null_statement)
957  << FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
958  return true;
959 }
960 
961 bool Parser::isExprValueDiscarded() {
962  if (Actions.isCurCompoundStmtAStmtExpr()) {
963  // Look to see if the next two tokens close the statement expression;
964  // if so, this expression statement is the last statement in a
965  // statment expression.
966  return Tok.isNot(tok::r_brace) || NextToken().isNot(tok::r_paren);
967  }
968  return true;
969 }
970 
971 /// ParseCompoundStatementBody - Parse a sequence of statements and invoke the
972 /// ActOnCompoundStmt action. This expects the '{' to be the current token, and
973 /// consume the '}' at the end of the block. It does not manipulate the scope
974 /// stack.
975 StmtResult Parser::ParseCompoundStatementBody(bool isStmtExpr) {
976  PrettyStackTraceLoc CrashInfo(PP.getSourceManager(),
977  Tok.getLocation(),
978  "in compound statement ('{}')");
979 
980  // Record the state of the FP_CONTRACT pragma, restore on leaving the
981  // compound statement.
982  Sema::FPContractStateRAII SaveFPContractState(Actions);
983 
984  InMessageExpressionRAIIObject InMessage(*this, false);
985  BalancedDelimiterTracker T(*this, tok::l_brace);
986  if (T.consumeOpen())
987  return StmtError();
988 
989  Sema::CompoundScopeRAII CompoundScope(Actions, isStmtExpr);
990 
991  // Parse any pragmas at the beginning of the compound statement.
992  ParseCompoundStatementLeadingPragmas();
993 
994  StmtVector Stmts;
995 
996  // "__label__ X, Y, Z;" is the GNU "Local Label" extension. These are
997  // only allowed at the start of a compound stmt regardless of the language.
998  while (Tok.is(tok::kw___label__)) {
999  SourceLocation LabelLoc = ConsumeToken();
1000 
1001  SmallVector<Decl *, 8> DeclsInGroup;
1002  while (1) {
1003  if (Tok.isNot(tok::identifier)) {
1004  Diag(Tok, diag::err_expected) << tok::identifier;
1005  break;
1006  }
1007 
1008  IdentifierInfo *II = Tok.getIdentifierInfo();
1009  SourceLocation IdLoc = ConsumeToken();
1010  DeclsInGroup.push_back(Actions.LookupOrCreateLabel(II, IdLoc, LabelLoc));
1011 
1012  if (!TryConsumeToken(tok::comma))
1013  break;
1014  }
1015 
1016  DeclSpec DS(AttrFactory);
1017  DeclGroupPtrTy Res =
1018  Actions.FinalizeDeclaratorGroup(getCurScope(), DS, DeclsInGroup);
1019  StmtResult R = Actions.ActOnDeclStmt(Res, LabelLoc, Tok.getLocation());
1020 
1021  ExpectAndConsumeSemi(diag::err_expected_semi_declaration);
1022  if (R.isUsable())
1023  Stmts.push_back(R.get());
1024  }
1025 
1026  while (!tryParseMisplacedModuleImport() && Tok.isNot(tok::r_brace) &&
1027  Tok.isNot(tok::eof)) {
1028  if (Tok.is(tok::annot_pragma_unused)) {
1029  HandlePragmaUnused();
1030  continue;
1031  }
1032 
1033  if (ConsumeNullStmt(Stmts))
1034  continue;
1035 
1036  StmtResult R;
1037  if (Tok.isNot(tok::kw___extension__)) {
1038  R = ParseStatementOrDeclaration(Stmts, ACK_Any);
1039  } else {
1040  // __extension__ can start declarations and it can also be a unary
1041  // operator for expressions. Consume multiple __extension__ markers here
1042  // until we can determine which is which.
1043  // FIXME: This loses extension expressions in the AST!
1044  SourceLocation ExtLoc = ConsumeToken();
1045  while (Tok.is(tok::kw___extension__))
1046  ConsumeToken();
1047 
1048  ParsedAttributesWithRange attrs(AttrFactory);
1049  MaybeParseCXX11Attributes(attrs, nullptr,
1050  /*MightBeObjCMessageSend*/ true);
1051 
1052  // If this is the start of a declaration, parse it as such.
1053  if (isDeclarationStatement()) {
1054  // __extension__ silences extension warnings in the subdeclaration.
1055  // FIXME: Save the __extension__ on the decl as a node somehow?
1056  ExtensionRAIIObject O(Diags);
1057 
1058  SourceLocation DeclStart = Tok.getLocation(), DeclEnd;
1059  DeclGroupPtrTy Res =
1060  ParseDeclaration(DeclaratorContext::BlockContext, DeclEnd, attrs);
1061  R = Actions.ActOnDeclStmt(Res, DeclStart, DeclEnd);
1062  } else {
1063  // Otherwise this was a unary __extension__ marker.
1064  ExprResult Res(ParseExpressionWithLeadingExtension(ExtLoc));
1065 
1066  if (Res.isInvalid()) {
1067  SkipUntil(tok::semi);
1068  continue;
1069  }
1070 
1071  // FIXME: Use attributes?
1072  // Eat the semicolon at the end of stmt and convert the expr into a
1073  // statement.
1074  ExpectAndConsumeSemi(diag::err_expected_semi_after_expr);
1075  R = Actions.ActOnExprStmt(Res, isExprValueDiscarded());
1076  }
1077  }
1078 
1079  if (R.isUsable())
1080  Stmts.push_back(R.get());
1081  }
1082 
1083  SourceLocation CloseLoc = Tok.getLocation();
1084 
1085  // We broke out of the while loop because we found a '}' or EOF.
1086  if (!T.consumeClose())
1087  // Recover by creating a compound statement with what we parsed so far,
1088  // instead of dropping everything and returning StmtError();
1089  CloseLoc = T.getCloseLocation();
1090 
1091  return Actions.ActOnCompoundStmt(T.getOpenLocation(), CloseLoc,
1092  Stmts, isStmtExpr);
1093 }
1094 
1095 /// ParseParenExprOrCondition:
1096 /// [C ] '(' expression ')'
1097 /// [C++] '(' condition ')'
1098 /// [C++1z] '(' init-statement[opt] condition ')'
1099 ///
1100 /// This function parses and performs error recovery on the specified condition
1101 /// or expression (depending on whether we're in C++ or C mode). This function
1102 /// goes out of its way to recover well. It returns true if there was a parser
1103 /// error (the right paren couldn't be found), which indicates that the caller
1104 /// should try to recover harder. It returns false if the condition is
1105 /// successfully parsed. Note that a successful parse can still have semantic
1106 /// errors in the condition.
1107 bool Parser::ParseParenExprOrCondition(StmtResult *InitStmt,
1108  Sema::ConditionResult &Cond,
1109  SourceLocation Loc,
1110  Sema::ConditionKind CK) {
1111  BalancedDelimiterTracker T(*this, tok::l_paren);
1112  T.consumeOpen();
1113 
1114  if (getLangOpts().CPlusPlus)
1115  Cond = ParseCXXCondition(InitStmt, Loc, CK);
1116  else {
1117  ExprResult CondExpr = ParseExpression();
1118 
1119  // If required, convert to a boolean value.
1120  if (CondExpr.isInvalid())
1121  Cond = Sema::ConditionError();
1122  else
1123  Cond = Actions.ActOnCondition(getCurScope(), Loc, CondExpr.get(), CK);
1124  }
1125 
1126  // If the parser was confused by the condition and we don't have a ')', try to
1127  // recover by skipping ahead to a semi and bailing out. If condexp is
1128  // semantically invalid but we have well formed code, keep going.
1129  if (Cond.isInvalid() && Tok.isNot(tok::r_paren)) {
1130  SkipUntil(tok::semi);
1131  // Skipping may have stopped if it found the containing ')'. If so, we can
1132  // continue parsing the if statement.
1133  if (Tok.isNot(tok::r_paren))
1134  return true;
1135  }
1136 
1137  // Otherwise the condition is valid or the rparen is present.
1138  T.consumeClose();
1139 
1140  // Check for extraneous ')'s to catch things like "if (foo())) {". We know
1141  // that all callers are looking for a statement after the condition, so ")"
1142  // isn't valid.
1143  while (Tok.is(tok::r_paren)) {
1144  Diag(Tok, diag::err_extraneous_rparen_in_condition)
1145  << FixItHint::CreateRemoval(Tok.getLocation());
1146  ConsumeParen();
1147  }
1148 
1149  return false;
1150 }
1151 
1152 
1153 /// ParseIfStatement
1154 /// if-statement: [C99 6.8.4.1]
1155 /// 'if' '(' expression ')' statement
1156 /// 'if' '(' expression ')' statement 'else' statement
1157 /// [C++] 'if' '(' condition ')' statement
1158 /// [C++] 'if' '(' condition ')' statement 'else' statement
1159 ///
1160 StmtResult Parser::ParseIfStatement(SourceLocation *TrailingElseLoc) {
1161  assert(Tok.is(tok::kw_if) && "Not an if stmt!");
1162  SourceLocation IfLoc = ConsumeToken(); // eat the 'if'.
1163 
1164  bool IsConstexpr = false;
1165  if (Tok.is(tok::kw_constexpr)) {
1166  Diag(Tok, getLangOpts().CPlusPlus17 ? diag::warn_cxx14_compat_constexpr_if
1167  : diag::ext_constexpr_if);
1168  IsConstexpr = true;
1169  ConsumeToken();
1170  }
1171 
1172  if (Tok.isNot(tok::l_paren)) {
1173  Diag(Tok, diag::err_expected_lparen_after) << "if";
1174  SkipUntil(tok::semi);
1175  return StmtError();
1176  }
1177 
1178  bool C99orCXX = getLangOpts().C99 || getLangOpts().CPlusPlus;
1179 
1180  // C99 6.8.4p3 - In C99, the if statement is a block. This is not
1181  // the case for C90.
1182  //
1183  // C++ 6.4p3:
1184  // A name introduced by a declaration in a condition is in scope from its
1185  // point of declaration until the end of the substatements controlled by the
1186  // condition.
1187  // C++ 3.3.2p4:
1188  // Names declared in the for-init-statement, and in the condition of if,
1189  // while, for, and switch statements are local to the if, while, for, or
1190  // switch statement (including the controlled statement).
1191  //
1192  ParseScope IfScope(this, Scope::DeclScope | Scope::ControlScope, C99orCXX);
1193 
1194  // Parse the condition.
1195  StmtResult InitStmt;
1196  Sema::ConditionResult Cond;
1197  if (ParseParenExprOrCondition(&InitStmt, Cond, IfLoc,
1198  IsConstexpr ? Sema::ConditionKind::ConstexprIf
1200  return StmtError();
1201 
1202  llvm::Optional<bool> ConstexprCondition;
1203  if (IsConstexpr)
1204  ConstexprCondition = Cond.getKnownValue();
1205 
1206  // C99 6.8.4p3 - In C99, the body of the if statement is a scope, even if
1207  // there is no compound stmt. C90 does not have this clause. We only do this
1208  // if the body isn't a compound statement to avoid push/pop in common cases.
1209  //
1210  // C++ 6.4p1:
1211  // The substatement in a selection-statement (each substatement, in the else
1212  // form of the if statement) implicitly defines a local scope.
1213  //
1214  // For C++ we create a scope for the condition and a new scope for
1215  // substatements because:
1216  // -When the 'then' scope exits, we want the condition declaration to still be
1217  // active for the 'else' scope too.
1218  // -Sema will detect name clashes by considering declarations of a
1219  // 'ControlScope' as part of its direct subscope.
1220  // -If we wanted the condition and substatement to be in the same scope, we
1221  // would have to notify ParseStatement not to create a new scope. It's
1222  // simpler to let it create a new scope.
1223  //
1224  ParseScope InnerScope(this, Scope::DeclScope, C99orCXX, Tok.is(tok::l_brace));
1225 
1226  // Read the 'then' stmt.
1227  SourceLocation ThenStmtLoc = Tok.getLocation();
1228 
1229  SourceLocation InnerStatementTrailingElseLoc;
1230  StmtResult ThenStmt;
1231  {
1232  EnterExpressionEvaluationContext PotentiallyDiscarded(
1235  /*ShouldEnter=*/ConstexprCondition && !*ConstexprCondition);
1236  ThenStmt = ParseStatement(&InnerStatementTrailingElseLoc);
1237  }
1238 
1239  // Pop the 'if' scope if needed.
1240  InnerScope.Exit();
1241 
1242  // If it has an else, parse it.
1243  SourceLocation ElseLoc;
1244  SourceLocation ElseStmtLoc;
1245  StmtResult ElseStmt;
1246 
1247  if (Tok.is(tok::kw_else)) {
1248  if (TrailingElseLoc)
1249  *TrailingElseLoc = Tok.getLocation();
1250 
1251  ElseLoc = ConsumeToken();
1252  ElseStmtLoc = Tok.getLocation();
1253 
1254  // C99 6.8.4p3 - In C99, the body of the if statement is a scope, even if
1255  // there is no compound stmt. C90 does not have this clause. We only do
1256  // this if the body isn't a compound statement to avoid push/pop in common
1257  // cases.
1258  //
1259  // C++ 6.4p1:
1260  // The substatement in a selection-statement (each substatement, in the else
1261  // form of the if statement) implicitly defines a local scope.
1262  //
1263  ParseScope InnerScope(this, Scope::DeclScope, C99orCXX,
1264  Tok.is(tok::l_brace));
1265 
1266  EnterExpressionEvaluationContext PotentiallyDiscarded(
1269  /*ShouldEnter=*/ConstexprCondition && *ConstexprCondition);
1270  ElseStmt = ParseStatement();
1271 
1272  // Pop the 'else' scope if needed.
1273  InnerScope.Exit();
1274  } else if (Tok.is(tok::code_completion)) {
1275  Actions.CodeCompleteAfterIf(getCurScope());
1276  cutOffParsing();
1277  return StmtError();
1278  } else if (InnerStatementTrailingElseLoc.isValid()) {
1279  Diag(InnerStatementTrailingElseLoc, diag::warn_dangling_else);
1280  }
1281 
1282  IfScope.Exit();
1283 
1284  // If the then or else stmt is invalid and the other is valid (and present),
1285  // make turn the invalid one into a null stmt to avoid dropping the other
1286  // part. If both are invalid, return error.
1287  if ((ThenStmt.isInvalid() && ElseStmt.isInvalid()) ||
1288  (ThenStmt.isInvalid() && ElseStmt.get() == nullptr) ||
1289  (ThenStmt.get() == nullptr && ElseStmt.isInvalid())) {
1290  // Both invalid, or one is invalid and other is non-present: return error.
1291  return StmtError();
1292  }
1293 
1294  // Now if either are invalid, replace with a ';'.
1295  if (ThenStmt.isInvalid())
1296  ThenStmt = Actions.ActOnNullStmt(ThenStmtLoc);
1297  if (ElseStmt.isInvalid())
1298  ElseStmt = Actions.ActOnNullStmt(ElseStmtLoc);
1299 
1300  return Actions.ActOnIfStmt(IfLoc, IsConstexpr, InitStmt.get(), Cond,
1301  ThenStmt.get(), ElseLoc, ElseStmt.get());
1302 }
1303 
1304 /// ParseSwitchStatement
1305 /// switch-statement:
1306 /// 'switch' '(' expression ')' statement
1307 /// [C++] 'switch' '(' condition ')' statement
1308 StmtResult Parser::ParseSwitchStatement(SourceLocation *TrailingElseLoc) {
1309  assert(Tok.is(tok::kw_switch) && "Not a switch stmt!");
1310  SourceLocation SwitchLoc = ConsumeToken(); // eat the 'switch'.
1311 
1312  if (Tok.isNot(tok::l_paren)) {
1313  Diag(Tok, diag::err_expected_lparen_after) << "switch";
1314  SkipUntil(tok::semi);
1315  return StmtError();
1316  }
1317 
1318  bool C99orCXX = getLangOpts().C99 || getLangOpts().CPlusPlus;
1319 
1320  // C99 6.8.4p3 - In C99, the switch statement is a block. This is
1321  // not the case for C90. Start the switch scope.
1322  //
1323  // C++ 6.4p3:
1324  // A name introduced by a declaration in a condition is in scope from its
1325  // point of declaration until the end of the substatements controlled by the
1326  // condition.
1327  // C++ 3.3.2p4:
1328  // Names declared in the for-init-statement, and in the condition of if,
1329  // while, for, and switch statements are local to the if, while, for, or
1330  // switch statement (including the controlled statement).
1331  //
1332  unsigned ScopeFlags = Scope::SwitchScope;
1333  if (C99orCXX)
1334  ScopeFlags |= Scope::DeclScope | Scope::ControlScope;
1335  ParseScope SwitchScope(this, ScopeFlags);
1336 
1337  // Parse the condition.
1338  StmtResult InitStmt;
1339  Sema::ConditionResult Cond;
1340  if (ParseParenExprOrCondition(&InitStmt, Cond, SwitchLoc,
1342  return StmtError();
1343 
1344  StmtResult Switch =
1345  Actions.ActOnStartOfSwitchStmt(SwitchLoc, InitStmt.get(), Cond);
1346 
1347  if (Switch.isInvalid()) {
1348  // Skip the switch body.
1349  // FIXME: This is not optimal recovery, but parsing the body is more
1350  // dangerous due to the presence of case and default statements, which
1351  // will have no place to connect back with the switch.
1352  if (Tok.is(tok::l_brace)) {
1353  ConsumeBrace();
1354  SkipUntil(tok::r_brace);
1355  } else
1356  SkipUntil(tok::semi);
1357  return Switch;
1358  }
1359 
1360  // C99 6.8.4p3 - In C99, the body of the switch statement is a scope, even if
1361  // there is no compound stmt. C90 does not have this clause. We only do this
1362  // if the body isn't a compound statement to avoid push/pop in common cases.
1363  //
1364  // C++ 6.4p1:
1365  // The substatement in a selection-statement (each substatement, in the else
1366  // form of the if statement) implicitly defines a local scope.
1367  //
1368  // See comments in ParseIfStatement for why we create a scope for the
1369  // condition and a new scope for substatement in C++.
1370  //
1372  ParseScope InnerScope(this, Scope::DeclScope, C99orCXX, Tok.is(tok::l_brace));
1373 
1374  // We have incremented the mangling number for the SwitchScope and the
1375  // InnerScope, which is one too many.
1376  if (C99orCXX)
1378 
1379  // Read the body statement.
1380  StmtResult Body(ParseStatement(TrailingElseLoc));
1381 
1382  // Pop the scopes.
1383  InnerScope.Exit();
1384  SwitchScope.Exit();
1385 
1386  return Actions.ActOnFinishSwitchStmt(SwitchLoc, Switch.get(), Body.get());
1387 }
1388 
1389 /// ParseWhileStatement
1390 /// while-statement: [C99 6.8.5.1]
1391 /// 'while' '(' expression ')' statement
1392 /// [C++] 'while' '(' condition ')' statement
1393 StmtResult Parser::ParseWhileStatement(SourceLocation *TrailingElseLoc) {
1394  assert(Tok.is(tok::kw_while) && "Not a while stmt!");
1395  SourceLocation WhileLoc = Tok.getLocation();
1396  ConsumeToken(); // eat the 'while'.
1397 
1398  if (Tok.isNot(tok::l_paren)) {
1399  Diag(Tok, diag::err_expected_lparen_after) << "while";
1400  SkipUntil(tok::semi);
1401  return StmtError();
1402  }
1403 
1404  bool C99orCXX = getLangOpts().C99 || getLangOpts().CPlusPlus;
1405 
1406  // C99 6.8.5p5 - In C99, the while statement is a block. This is not
1407  // the case for C90. Start the loop scope.
1408  //
1409  // C++ 6.4p3:
1410  // A name introduced by a declaration in a condition is in scope from its
1411  // point of declaration until the end of the substatements controlled by the
1412  // condition.
1413  // C++ 3.3.2p4:
1414  // Names declared in the for-init-statement, and in the condition of if,
1415  // while, for, and switch statements are local to the if, while, for, or
1416  // switch statement (including the controlled statement).
1417  //
1418  unsigned ScopeFlags;
1419  if (C99orCXX)
1420  ScopeFlags = Scope::BreakScope | Scope::ContinueScope |
1422  else
1423  ScopeFlags = Scope::BreakScope | Scope::ContinueScope;
1424  ParseScope WhileScope(this, ScopeFlags);
1425 
1426  // Parse the condition.
1427  Sema::ConditionResult Cond;
1428  if (ParseParenExprOrCondition(nullptr, Cond, WhileLoc,
1429  Sema::ConditionKind::Boolean))
1430  return StmtError();
1431 
1432  // C99 6.8.5p5 - In C99, the body of the while statement is a scope, even if
1433  // there is no compound stmt. C90 does not have this clause. We only do this
1434  // if the body isn't a compound statement to avoid push/pop in common cases.
1435  //
1436  // C++ 6.5p2:
1437  // The substatement in an iteration-statement implicitly defines a local scope
1438  // which is entered and exited each time through the loop.
1439  //
1440  // See comments in ParseIfStatement for why we create a scope for the
1441  // condition and a new scope for substatement in C++.
1442  //
1443  ParseScope InnerScope(this, Scope::DeclScope, C99orCXX, Tok.is(tok::l_brace));
1444 
1445  // Read the body statement.
1446  StmtResult Body(ParseStatement(TrailingElseLoc));
1447 
1448  // Pop the body scope if needed.
1449  InnerScope.Exit();
1450  WhileScope.Exit();
1451 
1452  if (Cond.isInvalid() || Body.isInvalid())
1453  return StmtError();
1454 
1455  return Actions.ActOnWhileStmt(WhileLoc, Cond, Body.get());
1456 }
1457 
1458 /// ParseDoStatement
1459 /// do-statement: [C99 6.8.5.2]
1460 /// 'do' statement 'while' '(' expression ')' ';'
1461 /// Note: this lets the caller parse the end ';'.
1462 StmtResult Parser::ParseDoStatement() {
1463  assert(Tok.is(tok::kw_do) && "Not a do stmt!");
1464  SourceLocation DoLoc = ConsumeToken(); // eat the 'do'.
1465 
1466  // C99 6.8.5p5 - In C99, the do statement is a block. This is not
1467  // the case for C90. Start the loop scope.
1468  unsigned ScopeFlags;
1469  if (getLangOpts().C99)
1471  else
1472  ScopeFlags = Scope::BreakScope | Scope::ContinueScope;
1473 
1474  ParseScope DoScope(this, ScopeFlags);
1475 
1476  // C99 6.8.5p5 - In C99, the body of the do statement is a scope, even if
1477  // there is no compound stmt. C90 does not have this clause. We only do this
1478  // if the body isn't a compound statement to avoid push/pop in common cases.
1479  //
1480  // C++ 6.5p2:
1481  // The substatement in an iteration-statement implicitly defines a local scope
1482  // which is entered and exited each time through the loop.
1483  //
1484  bool C99orCXX = getLangOpts().C99 || getLangOpts().CPlusPlus;
1485  ParseScope InnerScope(this, Scope::DeclScope, C99orCXX, Tok.is(tok::l_brace));
1486 
1487  // Read the body statement.
1488  StmtResult Body(ParseStatement());
1489 
1490  // Pop the body scope if needed.
1491  InnerScope.Exit();
1492 
1493  if (Tok.isNot(tok::kw_while)) {
1494  if (!Body.isInvalid()) {
1495  Diag(Tok, diag::err_expected_while);
1496  Diag(DoLoc, diag::note_matching) << "'do'";
1497  SkipUntil(tok::semi, StopBeforeMatch);
1498  }
1499  return StmtError();
1500  }
1501  SourceLocation WhileLoc = ConsumeToken();
1502 
1503  if (Tok.isNot(tok::l_paren)) {
1504  Diag(Tok, diag::err_expected_lparen_after) << "do/while";
1505  SkipUntil(tok::semi, StopBeforeMatch);
1506  return StmtError();
1507  }
1508 
1509  // Parse the parenthesized expression.
1510  BalancedDelimiterTracker T(*this, tok::l_paren);
1511  T.consumeOpen();
1512 
1513  // A do-while expression is not a condition, so can't have attributes.
1514  DiagnoseAndSkipCXX11Attributes();
1515 
1516  ExprResult Cond = ParseExpression();
1517  // Correct the typos in condition before closing the scope.
1518  if (Cond.isUsable())
1519  Cond = Actions.CorrectDelayedTyposInExpr(Cond);
1520  T.consumeClose();
1521  DoScope.Exit();
1522 
1523  if (Cond.isInvalid() || Body.isInvalid())
1524  return StmtError();
1525 
1526  return Actions.ActOnDoStmt(DoLoc, Body.get(), WhileLoc, T.getOpenLocation(),
1527  Cond.get(), T.getCloseLocation());
1528 }
1529 
1530 bool Parser::isForRangeIdentifier() {
1531  assert(Tok.is(tok::identifier));
1532 
1533  const Token &Next = NextToken();
1534  if (Next.is(tok::colon))
1535  return true;
1536 
1537  if (Next.isOneOf(tok::l_square, tok::kw_alignas)) {
1538  TentativeParsingAction PA(*this);
1539  ConsumeToken();
1540  SkipCXX11Attributes();
1541  bool Result = Tok.is(tok::colon);
1542  PA.Revert();
1543  return Result;
1544  }
1545 
1546  return false;
1547 }
1548 
1549 /// ParseForStatement
1550 /// for-statement: [C99 6.8.5.3]
1551 /// 'for' '(' expr[opt] ';' expr[opt] ';' expr[opt] ')' statement
1552 /// 'for' '(' declaration expr[opt] ';' expr[opt] ')' statement
1553 /// [C++] 'for' '(' for-init-statement condition[opt] ';' expression[opt] ')'
1554 /// [C++] statement
1555 /// [C++0x] 'for'
1556 /// 'co_await'[opt] [Coroutines]
1557 /// '(' for-range-declaration ':' for-range-initializer ')'
1558 /// statement
1559 /// [OBJC2] 'for' '(' declaration 'in' expr ')' statement
1560 /// [OBJC2] 'for' '(' expr 'in' expr ')' statement
1561 ///
1562 /// [C++] for-init-statement:
1563 /// [C++] expression-statement
1564 /// [C++] simple-declaration
1565 ///
1566 /// [C++0x] for-range-declaration:
1567 /// [C++0x] attribute-specifier-seq[opt] type-specifier-seq declarator
1568 /// [C++0x] for-range-initializer:
1569 /// [C++0x] expression
1570 /// [C++0x] braced-init-list [TODO]
1571 StmtResult Parser::ParseForStatement(SourceLocation *TrailingElseLoc) {
1572  assert(Tok.is(tok::kw_for) && "Not a for stmt!");
1573  SourceLocation ForLoc = ConsumeToken(); // eat the 'for'.
1574 
1575  SourceLocation CoawaitLoc;
1576  if (Tok.is(tok::kw_co_await))
1577  CoawaitLoc = ConsumeToken();
1578 
1579  if (Tok.isNot(tok::l_paren)) {
1580  Diag(Tok, diag::err_expected_lparen_after) << "for";
1581  SkipUntil(tok::semi);
1582  return StmtError();
1583  }
1584 
1585  bool C99orCXXorObjC = getLangOpts().C99 || getLangOpts().CPlusPlus ||
1586  getLangOpts().ObjC;
1587 
1588  // C99 6.8.5p5 - In C99, the for statement is a block. This is not
1589  // the case for C90. Start the loop scope.
1590  //
1591  // C++ 6.4p3:
1592  // A name introduced by a declaration in a condition is in scope from its
1593  // point of declaration until the end of the substatements controlled by the
1594  // condition.
1595  // C++ 3.3.2p4:
1596  // Names declared in the for-init-statement, and in the condition of if,
1597  // while, for, and switch statements are local to the if, while, for, or
1598  // switch statement (including the controlled statement).
1599  // C++ 6.5.3p1:
1600  // Names declared in the for-init-statement are in the same declarative-region
1601  // as those declared in the condition.
1602  //
1603  unsigned ScopeFlags = 0;
1604  if (C99orCXXorObjC)
1605  ScopeFlags = Scope::DeclScope | Scope::ControlScope;
1606 
1607  ParseScope ForScope(this, ScopeFlags);
1608 
1609  BalancedDelimiterTracker T(*this, tok::l_paren);
1610  T.consumeOpen();
1611 
1612  ExprResult Value;
1613 
1614  bool ForEach = false;
1615  StmtResult FirstPart;
1616  Sema::ConditionResult SecondPart;
1617  ExprResult Collection;
1618  ForRangeInfo ForRangeInfo;
1619  FullExprArg ThirdPart(Actions);
1620 
1621  if (Tok.is(tok::code_completion)) {
1622  Actions.CodeCompleteOrdinaryName(getCurScope(),
1623  C99orCXXorObjC? Sema::PCC_ForInit
1625  cutOffParsing();
1626  return StmtError();
1627  }
1628 
1629  ParsedAttributesWithRange attrs(AttrFactory);
1630  MaybeParseCXX11Attributes(attrs);
1631 
1632  SourceLocation EmptyInitStmtSemiLoc;
1633 
1634  // Parse the first part of the for specifier.
1635  if (Tok.is(tok::semi)) { // for (;
1636  ProhibitAttributes(attrs);
1637  // no first part, eat the ';'.
1638  SourceLocation SemiLoc = Tok.getLocation();
1639  if (!Tok.hasLeadingEmptyMacro() && !SemiLoc.isMacroID())
1640  EmptyInitStmtSemiLoc = SemiLoc;
1641  ConsumeToken();
1642  } else if (getLangOpts().CPlusPlus && Tok.is(tok::identifier) &&
1643  isForRangeIdentifier()) {
1644  ProhibitAttributes(attrs);
1645  IdentifierInfo *Name = Tok.getIdentifierInfo();
1646  SourceLocation Loc = ConsumeToken();
1647  MaybeParseCXX11Attributes(attrs);
1648 
1649  ForRangeInfo.ColonLoc = ConsumeToken();
1650  if (Tok.is(tok::l_brace))
1651  ForRangeInfo.RangeExpr = ParseBraceInitializer();
1652  else
1653  ForRangeInfo.RangeExpr = ParseExpression();
1654 
1655  Diag(Loc, diag::err_for_range_identifier)
1656  << ((getLangOpts().CPlusPlus11 && !getLangOpts().CPlusPlus17)
1657  ? FixItHint::CreateInsertion(Loc, "auto &&")
1658  : FixItHint());
1659 
1660  ForRangeInfo.LoopVar = Actions.ActOnCXXForRangeIdentifier(
1661  getCurScope(), Loc, Name, attrs, attrs.Range.getEnd());
1662  } else if (isForInitDeclaration()) { // for (int X = 4;
1663  ParenBraceBracketBalancer BalancerRAIIObj(*this);
1664 
1665  // Parse declaration, which eats the ';'.
1666  if (!C99orCXXorObjC) { // Use of C99-style for loops in C90 mode?
1667  Diag(Tok, diag::ext_c99_variable_decl_in_for_loop);
1668  Diag(Tok, diag::warn_gcc_variable_decl_in_for_loop);
1669  }
1670 
1671  // In C++0x, "for (T NS:a" might not be a typo for ::
1672  bool MightBeForRangeStmt = getLangOpts().CPlusPlus;
1673  ColonProtectionRAIIObject ColonProtection(*this, MightBeForRangeStmt);
1674 
1675  SourceLocation DeclStart = Tok.getLocation(), DeclEnd;
1676  DeclGroupPtrTy DG = ParseSimpleDeclaration(
1677  DeclaratorContext::ForContext, DeclEnd, attrs, false,
1678  MightBeForRangeStmt ? &ForRangeInfo : nullptr);
1679  FirstPart = Actions.ActOnDeclStmt(DG, DeclStart, Tok.getLocation());
1680  if (ForRangeInfo.ParsedForRangeDecl()) {
1681  Diag(ForRangeInfo.ColonLoc, getLangOpts().CPlusPlus11 ?
1682  diag::warn_cxx98_compat_for_range : diag::ext_for_range);
1683  ForRangeInfo.LoopVar = FirstPart;
1684  FirstPart = StmtResult();
1685  } else if (Tok.is(tok::semi)) { // for (int x = 4;
1686  ConsumeToken();
1687  } else if ((ForEach = isTokIdentifier_in())) {
1688  Actions.ActOnForEachDeclStmt(DG);
1689  // ObjC: for (id x in expr)
1690  ConsumeToken(); // consume 'in'
1691 
1692  if (Tok.is(tok::code_completion)) {
1693  Actions.CodeCompleteObjCForCollection(getCurScope(), DG);
1694  cutOffParsing();
1695  return StmtError();
1696  }
1697  Collection = ParseExpression();
1698  } else {
1699  Diag(Tok, diag::err_expected_semi_for);
1700  }
1701  } else {
1702  ProhibitAttributes(attrs);
1703  Value = Actions.CorrectDelayedTyposInExpr(ParseExpression());
1704 
1705  ForEach = isTokIdentifier_in();
1706 
1707  // Turn the expression into a stmt.
1708  if (!Value.isInvalid()) {
1709  if (ForEach)
1710  FirstPart = Actions.ActOnForEachLValueExpr(Value.get());
1711  else {
1712  // We already know this is not an init-statement within a for loop, so
1713  // if we are parsing a C++11 range-based for loop, we should treat this
1714  // expression statement as being a discarded value expression because
1715  // we will err below. This way we do not warn on an unused expression
1716  // that was an error in the first place, like with: for (expr : expr);
1717  bool IsRangeBasedFor =
1718  getLangOpts().CPlusPlus11 && !ForEach && Tok.is(tok::colon);
1719  FirstPart = Actions.ActOnExprStmt(Value, !IsRangeBasedFor);
1720  }
1721  }
1722 
1723  if (Tok.is(tok::semi)) {
1724  ConsumeToken();
1725  } else if (ForEach) {
1726  ConsumeToken(); // consume 'in'
1727 
1728  if (Tok.is(tok::code_completion)) {
1729  Actions.CodeCompleteObjCForCollection(getCurScope(), nullptr);
1730  cutOffParsing();
1731  return StmtError();
1732  }
1733  Collection = ParseExpression();
1734  } else if (getLangOpts().CPlusPlus11 && Tok.is(tok::colon) && FirstPart.get()) {
1735  // User tried to write the reasonable, but ill-formed, for-range-statement
1736  // for (expr : expr) { ... }
1737  Diag(Tok, diag::err_for_range_expected_decl)
1738  << FirstPart.get()->getSourceRange();
1739  SkipUntil(tok::r_paren, StopBeforeMatch);
1740  SecondPart = Sema::ConditionError();
1741  } else {
1742  if (!Value.isInvalid()) {
1743  Diag(Tok, diag::err_expected_semi_for);
1744  } else {
1745  // Skip until semicolon or rparen, don't consume it.
1746  SkipUntil(tok::r_paren, StopAtSemi | StopBeforeMatch);
1747  if (Tok.is(tok::semi))
1748  ConsumeToken();
1749  }
1750  }
1751  }
1752 
1753  // Parse the second part of the for specifier.
1755  if (!ForEach && !ForRangeInfo.ParsedForRangeDecl() &&
1756  !SecondPart.isInvalid()) {
1757  // Parse the second part of the for specifier.
1758  if (Tok.is(tok::semi)) { // for (...;;
1759  // no second part.
1760  } else if (Tok.is(tok::r_paren)) {
1761  // missing both semicolons.
1762  } else {
1763  if (getLangOpts().CPlusPlus) {
1764  // C++2a: We've parsed an init-statement; we might have a
1765  // for-range-declaration next.
1766  bool MightBeForRangeStmt = !ForRangeInfo.ParsedForRangeDecl();
1767  ColonProtectionRAIIObject ColonProtection(*this, MightBeForRangeStmt);
1768  SecondPart =
1769  ParseCXXCondition(nullptr, ForLoc, Sema::ConditionKind::Boolean,
1770  MightBeForRangeStmt ? &ForRangeInfo : nullptr);
1771 
1772  if (ForRangeInfo.ParsedForRangeDecl()) {
1773  Diag(FirstPart.get() ? FirstPart.get()->getBeginLoc()
1774  : ForRangeInfo.ColonLoc,
1775  getLangOpts().CPlusPlus2a
1776  ? diag::warn_cxx17_compat_for_range_init_stmt
1777  : diag::ext_for_range_init_stmt)
1778  << (FirstPart.get() ? FirstPart.get()->getSourceRange()
1779  : SourceRange());
1780  if (EmptyInitStmtSemiLoc.isValid()) {
1781  Diag(EmptyInitStmtSemiLoc, diag::warn_empty_init_statement)
1782  << /*for-loop*/ 2
1783  << FixItHint::CreateRemoval(EmptyInitStmtSemiLoc);
1784  }
1785  }
1786  } else {
1787  ExprResult SecondExpr = ParseExpression();
1788  if (SecondExpr.isInvalid())
1789  SecondPart = Sema::ConditionError();
1790  else
1791  SecondPart =
1792  Actions.ActOnCondition(getCurScope(), ForLoc, SecondExpr.get(),
1794  }
1795  }
1796  }
1797 
1798  // Parse the third part of the for statement.
1799  if (!ForEach && !ForRangeInfo.ParsedForRangeDecl()) {
1800  if (Tok.isNot(tok::semi)) {
1801  if (!SecondPart.isInvalid())
1802  Diag(Tok, diag::err_expected_semi_for);
1803  else
1804  // Skip until semicolon or rparen, don't consume it.
1805  SkipUntil(tok::r_paren, StopAtSemi | StopBeforeMatch);
1806  }
1807 
1808  if (Tok.is(tok::semi)) {
1809  ConsumeToken();
1810  }
1811 
1812  if (Tok.isNot(tok::r_paren)) { // for (...;...;)
1813  ExprResult Third = ParseExpression();
1814  // FIXME: The C++11 standard doesn't actually say that this is a
1815  // discarded-value expression, but it clearly should be.
1816  ThirdPart = Actions.MakeFullDiscardedValueExpr(Third.get());
1817  }
1818  }
1819  // Match the ')'.
1820  T.consumeClose();
1821 
1822  // C++ Coroutines [stmt.iter]:
1823  // 'co_await' can only be used for a range-based for statement.
1824  if (CoawaitLoc.isValid() && !ForRangeInfo.ParsedForRangeDecl()) {
1825  Diag(CoawaitLoc, diag::err_for_co_await_not_range_for);
1826  CoawaitLoc = SourceLocation();
1827  }
1828 
1829  // We need to perform most of the semantic analysis for a C++0x for-range
1830  // statememt before parsing the body, in order to be able to deduce the type
1831  // of an auto-typed loop variable.
1832  StmtResult ForRangeStmt;
1833  StmtResult ForEachStmt;
1834 
1835  if (ForRangeInfo.ParsedForRangeDecl()) {
1836  ExprResult CorrectedRange =
1837  Actions.CorrectDelayedTyposInExpr(ForRangeInfo.RangeExpr.get());
1838  ForRangeStmt = Actions.ActOnCXXForRangeStmt(
1839  getCurScope(), ForLoc, CoawaitLoc, FirstPart.get(),
1840  ForRangeInfo.LoopVar.get(), ForRangeInfo.ColonLoc, CorrectedRange.get(),
1841  T.getCloseLocation(), Sema::BFRK_Build);
1842 
1843  // Similarly, we need to do the semantic analysis for a for-range
1844  // statement immediately in order to close over temporaries correctly.
1845  } else if (ForEach) {
1846  ForEachStmt = Actions.ActOnObjCForCollectionStmt(ForLoc,
1847  FirstPart.get(),
1848  Collection.get(),
1849  T.getCloseLocation());
1850  } else {
1851  // In OpenMP loop region loop control variable must be captured and be
1852  // private. Perform analysis of first part (if any).
1853  if (getLangOpts().OpenMP && FirstPart.isUsable()) {
1854  Actions.ActOnOpenMPLoopInitialization(ForLoc, FirstPart.get());
1855  }
1856  }
1857 
1858  // C99 6.8.5p5 - In C99, the body of the for statement is a scope, even if
1859  // there is no compound stmt. C90 does not have this clause. We only do this
1860  // if the body isn't a compound statement to avoid push/pop in common cases.
1861  //
1862  // C++ 6.5p2:
1863  // The substatement in an iteration-statement implicitly defines a local scope
1864  // which is entered and exited each time through the loop.
1865  //
1866  // See comments in ParseIfStatement for why we create a scope for
1867  // for-init-statement/condition and a new scope for substatement in C++.
1868  //
1869  ParseScope InnerScope(this, Scope::DeclScope, C99orCXXorObjC,
1870  Tok.is(tok::l_brace));
1871 
1872  // The body of the for loop has the same local mangling number as the
1873  // for-init-statement.
1874  // It will only be incremented if the body contains other things that would
1875  // normally increment the mangling number (like a compound statement).
1876  if (C99orCXXorObjC)
1878 
1879  // Read the body statement.
1880  StmtResult Body(ParseStatement(TrailingElseLoc));
1881 
1882  // Pop the body scope if needed.
1883  InnerScope.Exit();
1884 
1885  // Leave the for-scope.
1886  ForScope.Exit();
1887 
1888  if (Body.isInvalid())
1889  return StmtError();
1890 
1891  if (ForEach)
1892  return Actions.FinishObjCForCollectionStmt(ForEachStmt.get(),
1893  Body.get());
1894 
1895  if (ForRangeInfo.ParsedForRangeDecl())
1896  return Actions.FinishCXXForRangeStmt(ForRangeStmt.get(), Body.get());
1897 
1898  return Actions.ActOnForStmt(ForLoc, T.getOpenLocation(), FirstPart.get(),
1899  SecondPart, ThirdPart, T.getCloseLocation(),
1900  Body.get());
1901 }
1902 
1903 /// ParseGotoStatement
1904 /// jump-statement:
1905 /// 'goto' identifier ';'
1906 /// [GNU] 'goto' '*' expression ';'
1907 ///
1908 /// Note: this lets the caller parse the end ';'.
1909 ///
1910 StmtResult Parser::ParseGotoStatement() {
1911  assert(Tok.is(tok::kw_goto) && "Not a goto stmt!");
1912  SourceLocation GotoLoc = ConsumeToken(); // eat the 'goto'.
1913 
1914  StmtResult Res;
1915  if (Tok.is(tok::identifier)) {
1916  LabelDecl *LD = Actions.LookupOrCreateLabel(Tok.getIdentifierInfo(),
1917  Tok.getLocation());
1918  Res = Actions.ActOnGotoStmt(GotoLoc, Tok.getLocation(), LD);
1919  ConsumeToken();
1920  } else if (Tok.is(tok::star)) {
1921  // GNU indirect goto extension.
1922  Diag(Tok, diag::ext_gnu_indirect_goto);
1923  SourceLocation StarLoc = ConsumeToken();
1925  if (R.isInvalid()) { // Skip to the semicolon, but don't consume it.
1926  SkipUntil(tok::semi, StopBeforeMatch);
1927  return StmtError();
1928  }
1929  Res = Actions.ActOnIndirectGotoStmt(GotoLoc, StarLoc, R.get());
1930  } else {
1931  Diag(Tok, diag::err_expected) << tok::identifier;
1932  return StmtError();
1933  }
1934 
1935  return Res;
1936 }
1937 
1938 /// ParseContinueStatement
1939 /// jump-statement:
1940 /// 'continue' ';'
1941 ///
1942 /// Note: this lets the caller parse the end ';'.
1943 ///
1944 StmtResult Parser::ParseContinueStatement() {
1945  SourceLocation ContinueLoc = ConsumeToken(); // eat the 'continue'.
1946  return Actions.ActOnContinueStmt(ContinueLoc, getCurScope());
1947 }
1948 
1949 /// ParseBreakStatement
1950 /// jump-statement:
1951 /// 'break' ';'
1952 ///
1953 /// Note: this lets the caller parse the end ';'.
1954 ///
1955 StmtResult Parser::ParseBreakStatement() {
1956  SourceLocation BreakLoc = ConsumeToken(); // eat the 'break'.
1957  return Actions.ActOnBreakStmt(BreakLoc, getCurScope());
1958 }
1959 
1960 /// ParseReturnStatement
1961 /// jump-statement:
1962 /// 'return' expression[opt] ';'
1963 /// 'return' braced-init-list ';'
1964 /// 'co_return' expression[opt] ';'
1965 /// 'co_return' braced-init-list ';'
1966 StmtResult Parser::ParseReturnStatement() {
1967  assert((Tok.is(tok::kw_return) || Tok.is(tok::kw_co_return)) &&
1968  "Not a return stmt!");
1969  bool IsCoreturn = Tok.is(tok::kw_co_return);
1970  SourceLocation ReturnLoc = ConsumeToken(); // eat the 'return'.
1971 
1972  ExprResult R;
1973  if (Tok.isNot(tok::semi)) {
1974  // FIXME: Code completion for co_return.
1975  if (Tok.is(tok::code_completion) && !IsCoreturn) {
1976  Actions.CodeCompleteReturn(getCurScope());
1977  cutOffParsing();
1978  return StmtError();
1979  }
1980 
1981  if (Tok.is(tok::l_brace) && getLangOpts().CPlusPlus) {
1982  R = ParseInitializer();
1983  if (R.isUsable())
1984  Diag(R.get()->getBeginLoc(),
1985  getLangOpts().CPlusPlus11
1986  ? diag::warn_cxx98_compat_generalized_initializer_lists
1987  : diag::ext_generalized_initializer_lists)
1988  << R.get()->getSourceRange();
1989  } else
1990  R = ParseExpression();
1991  if (R.isInvalid()) {
1992  SkipUntil(tok::r_brace, StopAtSemi | StopBeforeMatch);
1993  return StmtError();
1994  }
1995  }
1996  if (IsCoreturn)
1997  return Actions.ActOnCoreturnStmt(getCurScope(), ReturnLoc, R.get());
1998  return Actions.ActOnReturnStmt(ReturnLoc, R.get(), getCurScope());
1999 }
2000 
2001 StmtResult Parser::ParsePragmaLoopHint(StmtVector &Stmts,
2002  AllowedConstructsKind Allowed,
2003  SourceLocation *TrailingElseLoc,
2004  ParsedAttributesWithRange &Attrs) {
2005  // Create temporary attribute list.
2006  ParsedAttributesWithRange TempAttrs(AttrFactory);
2007 
2008  // Get loop hints and consume annotated token.
2009  while (Tok.is(tok::annot_pragma_loop_hint)) {
2010  LoopHint Hint;
2011  if (!HandlePragmaLoopHint(Hint))
2012  continue;
2013 
2014  ArgsUnion ArgHints[] = {Hint.PragmaNameLoc, Hint.OptionLoc, Hint.StateLoc,
2015  ArgsUnion(Hint.ValueExpr)};
2016  TempAttrs.addNew(Hint.PragmaNameLoc->Ident, Hint.Range, nullptr,
2017  Hint.PragmaNameLoc->Loc, ArgHints, 4,
2019  }
2020 
2021  // Get the next statement.
2022  MaybeParseCXX11Attributes(Attrs);
2023 
2024  StmtResult S = ParseStatementOrDeclarationAfterAttributes(
2025  Stmts, Allowed, TrailingElseLoc, Attrs);
2026 
2027  Attrs.takeAllFrom(TempAttrs);
2028  return S;
2029 }
2030 
2031 Decl *Parser::ParseFunctionStatementBody(Decl *Decl, ParseScope &BodyScope) {
2032  assert(Tok.is(tok::l_brace));
2033  SourceLocation LBraceLoc = Tok.getLocation();
2034 
2035  PrettyDeclStackTraceEntry CrashInfo(Actions.Context, Decl, LBraceLoc,
2036  "parsing function body");
2037 
2038  // Save and reset current vtordisp stack if we have entered a C++ method body.
2039  bool IsCXXMethod =
2040  getLangOpts().CPlusPlus && Decl && isa<CXXMethodDecl>(Decl);
2042  PragmaStackSentinel(Actions, "InternalPragmaState", IsCXXMethod);
2043 
2044  // Do not enter a scope for the brace, as the arguments are in the same scope
2045  // (the function body) as the body itself. Instead, just read the statement
2046  // list and put it into a CompoundStmt for safe keeping.
2047  StmtResult FnBody(ParseCompoundStatementBody());
2048 
2049  // If the function body could not be parsed, make a bogus compoundstmt.
2050  if (FnBody.isInvalid()) {
2051  Sema::CompoundScopeRAII CompoundScope(Actions);
2052  FnBody = Actions.ActOnCompoundStmt(LBraceLoc, LBraceLoc, None, false);
2053  }
2054 
2055  BodyScope.Exit();
2056  return Actions.ActOnFinishFunctionBody(Decl, FnBody.get());
2057 }
2058 
2059 /// ParseFunctionTryBlock - Parse a C++ function-try-block.
2060 ///
2061 /// function-try-block:
2062 /// 'try' ctor-initializer[opt] compound-statement handler-seq
2063 ///
2064 Decl *Parser::ParseFunctionTryBlock(Decl *Decl, ParseScope &BodyScope) {
2065  assert(Tok.is(tok::kw_try) && "Expected 'try'");
2066  SourceLocation TryLoc = ConsumeToken();
2067 
2068  PrettyDeclStackTraceEntry CrashInfo(Actions.Context, Decl, TryLoc,
2069  "parsing function try block");
2070 
2071  // Constructor initializer list?
2072  if (Tok.is(tok::colon))
2073  ParseConstructorInitializer(Decl);
2074  else
2075  Actions.ActOnDefaultCtorInitializers(Decl);
2076 
2077  // Save and reset current vtordisp stack if we have entered a C++ method body.
2078  bool IsCXXMethod =
2079  getLangOpts().CPlusPlus && Decl && isa<CXXMethodDecl>(Decl);
2081  PragmaStackSentinel(Actions, "InternalPragmaState", IsCXXMethod);
2082 
2083  SourceLocation LBraceLoc = Tok.getLocation();
2084  StmtResult FnBody(ParseCXXTryBlockCommon(TryLoc, /*FnTry*/true));
2085  // If we failed to parse the try-catch, we just give the function an empty
2086  // compound statement as the body.
2087  if (FnBody.isInvalid()) {
2088  Sema::CompoundScopeRAII CompoundScope(Actions);
2089  FnBody = Actions.ActOnCompoundStmt(LBraceLoc, LBraceLoc, None, false);
2090  }
2091 
2092  BodyScope.Exit();
2093  return Actions.ActOnFinishFunctionBody(Decl, FnBody.get());
2094 }
2095 
2096 bool Parser::trySkippingFunctionBody() {
2097  assert(SkipFunctionBodies &&
2098  "Should only be called when SkipFunctionBodies is enabled");
2099  if (!PP.isCodeCompletionEnabled()) {
2100  SkipFunctionBody();
2101  return true;
2102  }
2103 
2104  // We're in code-completion mode. Skip parsing for all function bodies unless
2105  // the body contains the code-completion point.
2106  TentativeParsingAction PA(*this);
2107  bool IsTryCatch = Tok.is(tok::kw_try);
2108  CachedTokens Toks;
2109  bool ErrorInPrologue = ConsumeAndStoreFunctionPrologue(Toks);
2110  if (llvm::any_of(Toks, [](const Token &Tok) {
2111  return Tok.is(tok::code_completion);
2112  })) {
2113  PA.Revert();
2114  return false;
2115  }
2116  if (ErrorInPrologue) {
2117  PA.Commit();
2119  return true;
2120  }
2121  if (!SkipUntil(tok::r_brace, StopAtCodeCompletion)) {
2122  PA.Revert();
2123  return false;
2124  }
2125  while (IsTryCatch && Tok.is(tok::kw_catch)) {
2126  if (!SkipUntil(tok::l_brace, StopAtCodeCompletion) ||
2127  !SkipUntil(tok::r_brace, StopAtCodeCompletion)) {
2128  PA.Revert();
2129  return false;
2130  }
2131  }
2132  PA.Commit();
2133  return true;
2134 }
2135 
2136 /// ParseCXXTryBlock - Parse a C++ try-block.
2137 ///
2138 /// try-block:
2139 /// 'try' compound-statement handler-seq
2140 ///
2141 StmtResult Parser::ParseCXXTryBlock() {
2142  assert(Tok.is(tok::kw_try) && "Expected 'try'");
2143 
2144  SourceLocation TryLoc = ConsumeToken();
2145  return ParseCXXTryBlockCommon(TryLoc);
2146 }
2147 
2148 /// ParseCXXTryBlockCommon - Parse the common part of try-block and
2149 /// function-try-block.
2150 ///
2151 /// try-block:
2152 /// 'try' compound-statement handler-seq
2153 ///
2154 /// function-try-block:
2155 /// 'try' ctor-initializer[opt] compound-statement handler-seq
2156 ///
2157 /// handler-seq:
2158 /// handler handler-seq[opt]
2159 ///
2160 /// [Borland] try-block:
2161 /// 'try' compound-statement seh-except-block
2162 /// 'try' compound-statement seh-finally-block
2163 ///
2164 StmtResult Parser::ParseCXXTryBlockCommon(SourceLocation TryLoc, bool FnTry) {
2165  if (Tok.isNot(tok::l_brace))
2166  return StmtError(Diag(Tok, diag::err_expected) << tok::l_brace);
2167 
2168  StmtResult TryBlock(ParseCompoundStatement(
2169  /*isStmtExpr=*/false, Scope::DeclScope | Scope::TryScope |
2171  (FnTry ? Scope::FnTryCatchScope : 0)));
2172  if (TryBlock.isInvalid())
2173  return TryBlock;
2174 
2175  // Borland allows SEH-handlers with 'try'
2176 
2177  if ((Tok.is(tok::identifier) &&
2178  Tok.getIdentifierInfo() == getSEHExceptKeyword()) ||
2179  Tok.is(tok::kw___finally)) {
2180  // TODO: Factor into common return ParseSEHHandlerCommon(...)
2181  StmtResult Handler;
2182  if(Tok.getIdentifierInfo() == getSEHExceptKeyword()) {
2183  SourceLocation Loc = ConsumeToken();
2184  Handler = ParseSEHExceptBlock(Loc);
2185  }
2186  else {
2187  SourceLocation Loc = ConsumeToken();
2188  Handler = ParseSEHFinallyBlock(Loc);
2189  }
2190  if(Handler.isInvalid())
2191  return Handler;
2192 
2193  return Actions.ActOnSEHTryBlock(true /* IsCXXTry */,
2194  TryLoc,
2195  TryBlock.get(),
2196  Handler.get());
2197  }
2198  else {
2199  StmtVector Handlers;
2200 
2201  // C++11 attributes can't appear here, despite this context seeming
2202  // statement-like.
2203  DiagnoseAndSkipCXX11Attributes();
2204 
2205  if (Tok.isNot(tok::kw_catch))
2206  return StmtError(Diag(Tok, diag::err_expected_catch));
2207  while (Tok.is(tok::kw_catch)) {
2208  StmtResult Handler(ParseCXXCatchBlock(FnTry));
2209  if (!Handler.isInvalid())
2210  Handlers.push_back(Handler.get());
2211  }
2212  // Don't bother creating the full statement if we don't have any usable
2213  // handlers.
2214  if (Handlers.empty())
2215  return StmtError();
2216 
2217  return Actions.ActOnCXXTryBlock(TryLoc, TryBlock.get(), Handlers);
2218  }
2219 }
2220 
2221 /// ParseCXXCatchBlock - Parse a C++ catch block, called handler in the standard
2222 ///
2223 /// handler:
2224 /// 'catch' '(' exception-declaration ')' compound-statement
2225 ///
2226 /// exception-declaration:
2227 /// attribute-specifier-seq[opt] type-specifier-seq declarator
2228 /// attribute-specifier-seq[opt] type-specifier-seq abstract-declarator[opt]
2229 /// '...'
2230 ///
2231 StmtResult Parser::ParseCXXCatchBlock(bool FnCatch) {
2232  assert(Tok.is(tok::kw_catch) && "Expected 'catch'");
2233 
2234  SourceLocation CatchLoc = ConsumeToken();
2235 
2236  BalancedDelimiterTracker T(*this, tok::l_paren);
2237  if (T.expectAndConsume())
2238  return StmtError();
2239 
2240  // C++ 3.3.2p3:
2241  // The name in a catch exception-declaration is local to the handler and
2242  // shall not be redeclared in the outermost block of the handler.
2243  ParseScope CatchScope(this, Scope::DeclScope | Scope::ControlScope |
2244  (FnCatch ? Scope::FnTryCatchScope : 0));
2245 
2246  // exception-declaration is equivalent to '...' or a parameter-declaration
2247  // without default arguments.
2248  Decl *ExceptionDecl = nullptr;
2249  if (Tok.isNot(tok::ellipsis)) {
2250  ParsedAttributesWithRange Attributes(AttrFactory);
2251  MaybeParseCXX11Attributes(Attributes);
2252 
2253  DeclSpec DS(AttrFactory);
2254  DS.takeAttributesFrom(Attributes);
2255 
2256  if (ParseCXXTypeSpecifierSeq(DS))
2257  return StmtError();
2258 
2260  ParseDeclarator(ExDecl);
2261  ExceptionDecl = Actions.ActOnExceptionDeclarator(getCurScope(), ExDecl);
2262  } else
2263  ConsumeToken();
2264 
2265  T.consumeClose();
2266  if (T.getCloseLocation().isInvalid())
2267  return StmtError();
2268 
2269  if (Tok.isNot(tok::l_brace))
2270  return StmtError(Diag(Tok, diag::err_expected) << tok::l_brace);
2271 
2272  // FIXME: Possible draft standard bug: attribute-specifier should be allowed?
2273  StmtResult Block(ParseCompoundStatement());
2274  if (Block.isInvalid())
2275  return Block;
2276 
2277  return Actions.ActOnCXXCatchBlock(CatchLoc, ExceptionDecl, Block.get());
2278 }
2279 
2280 void Parser::ParseMicrosoftIfExistsStatement(StmtVector &Stmts) {
2281  IfExistsCondition Result;
2282  if (ParseMicrosoftIfExistsCondition(Result))
2283  return;
2284 
2285  // Handle dependent statements by parsing the braces as a compound statement.
2286  // This is not the same behavior as Visual C++, which don't treat this as a
2287  // compound statement, but for Clang's type checking we can't have anything
2288  // inside these braces escaping to the surrounding code.
2289  if (Result.Behavior == IEB_Dependent) {
2290  if (!Tok.is(tok::l_brace)) {
2291  Diag(Tok, diag::err_expected) << tok::l_brace;
2292  return;
2293  }
2294 
2295  StmtResult Compound = ParseCompoundStatement();
2296  if (Compound.isInvalid())
2297  return;
2298 
2299  StmtResult DepResult = Actions.ActOnMSDependentExistsStmt(Result.KeywordLoc,
2300  Result.IsIfExists,
2301  Result.SS,
2302  Result.Name,
2303  Compound.get());
2304  if (DepResult.isUsable())
2305  Stmts.push_back(DepResult.get());
2306  return;
2307  }
2308 
2309  BalancedDelimiterTracker Braces(*this, tok::l_brace);
2310  if (Braces.consumeOpen()) {
2311  Diag(Tok, diag::err_expected) << tok::l_brace;
2312  return;
2313  }
2314 
2315  switch (Result.Behavior) {
2316  case IEB_Parse:
2317  // Parse the statements below.
2318  break;
2319 
2320  case IEB_Dependent:
2321  llvm_unreachable("Dependent case handled above");
2322 
2323  case IEB_Skip:
2324  Braces.skipToEnd();
2325  return;
2326  }
2327 
2328  // Condition is true, parse the statements.
2329  while (Tok.isNot(tok::r_brace)) {
2330  StmtResult R = ParseStatementOrDeclaration(Stmts, ACK_Any);
2331  if (R.isUsable())
2332  Stmts.push_back(R.get());
2333  }
2334  Braces.consumeClose();
2335 }
2336 
2337 bool Parser::ParseOpenCLUnrollHintAttribute(ParsedAttributes &Attrs) {
2338  MaybeParseGNUAttributes(Attrs);
2339 
2340  if (Attrs.empty())
2341  return true;
2342 
2343  if (Attrs.begin()->getKind() != ParsedAttr::AT_OpenCLUnrollHint)
2344  return true;
2345 
2346  if (!(Tok.is(tok::kw_for) || Tok.is(tok::kw_while) || Tok.is(tok::kw_do))) {
2347  Diag(Tok, diag::err_opencl_unroll_hint_on_non_loop);
2348  return false;
2349  }
2350  return true;
2351 }
void AddFlags(unsigned Flags)
Sets up the specified scope flags and adjusts the scope state variables accordingly.
Definition: Scope.cpp:108
IdentifierLoc * PragmaNameLoc
Definition: LoopHint.h:27
This is the scope of a C++ try statement.
Definition: Scope.h:102
Sema::FullExprArg FullExprArg
Definition: Parser.h:393
ExprResult ParseExpression(TypeCastState isTypeCast=NotTypeCast)
Simple precedence-based parser for binary/ternary operators.
Definition: ParseExpr.cpp:123
Simple class containing the result of Sema::CorrectTypo.
llvm::PointerUnion< Expr *, IdentifierLoc * > ArgsUnion
A union of the various pointer types that can be passed to an ParsedAttr as an argument.
Definition: ParsedAttr.h:105
static ConditionResult ConditionError()
Definition: Sema.h:9919
Stmt - This represents one statement.
Definition: Stmt.h:66
bool is(tok::TokenKind K) const
is/isNot - Predicates to check if this token is a specific kind, as in "if (Tok.is(tok::l_brace)) {...
Definition: Token.h:95
Decl - This represents one declaration (or definition), e.g.
Definition: DeclBase.h:87
Defines the PrettyStackTraceEntry class, which is used to make crashes give more contextual informati...
This is a while, do, switch, for, etc that can have break statements embedded into it...
Definition: Scope.h:52
IdentifierInfo * Ident
Definition: ParsedAttr.h:97
Represent a C++ namespace.
Definition: Decl.h:515
RAII object that enters a new expression evaluation context.
Definition: Sema.h:10853
Represents a variable declaration or definition.
Definition: Decl.h:813
ActionResult< Stmt * > StmtResult
Definition: Ownership.h:268
Information about one declarator, including the parsed type information and the identifier.
Definition: DeclSpec.h:1765
IdentifierLoc * OptionLoc
Definition: LoopHint.h:31
Records and restores the FP_CONTRACT state on entry/exit of compound statements.
Definition: Sema.h:1209
IdentifierLoc * StateLoc
Definition: LoopHint.h:34
NestedNameSpecifier * getCorrectionSpecifier() const
Gets the NestedNameSpecifier needed to use the typo correction.
DeclClass * getCorrectionDeclAs() const
RAII object that makes sure paren/bracket/brace count is correct after declaration/statement parsing...
ColonProtectionRAIIObject - This sets the Parser::ColonIsSacred bool and restores it when destroyed...
bool SkipUntil(tok::TokenKind T, SkipUntilFlags Flags=static_cast< SkipUntilFlags >(0))
SkipUntil - Read tokens until we get to the specified token, then consume it (unless StopBeforeMatch ...
Definition: Parser.h:1056
SourceLocation Loc
Definition: ParsedAttr.h:96
const Token & NextToken()
NextToken - This peeks ahead one token and returns it without consuming it.
Definition: Parser.h:724
bool TryConsumeToken(tok::TokenKind Expected)
Definition: Parser.h:425
One of these records is kept for each identifier that is lexed.
Base class for callback objects used by Sema::CorrectTypo to check the validity of a potential typo c...
Represents a member of a struct/union/class.
Definition: Decl.h:2579
void decrementMSManglingNumber()
Definition: Scope.h:302
Token - This structure provides full information about a lexed token.
Definition: Token.h:35
bool isInvalid() const
Definition: Sema.h:9908
RAII class that helps handle the parsing of an open/close delimiter pair, such as braces { ...
std::pair< VarDecl *, Expr * > get() const
Definition: Sema.h:9909
The controlling scope in a if/switch/while/for statement.
Definition: Scope.h:63
PtrTy get() const
Definition: Ownership.h:174
bool isNot(T Kind) const
Definition: FormatToken.h:323
This is a scope that corresponds to a switch statement.
Definition: Scope.h:99
const FormatToken & Tok
This is a while, do, for, which can have continue statements embedded into it.
Definition: Scope.h:56
Code completion occurs within an expression.
Definition: Sema.h:10311
StmtResult StmtError()
Definition: Ownership.h:284
If a crash happens while one of these objects are live, the message is printed out along with the spe...
The current expression occurs within a discarded statement.
llvm::Optional< bool > getKnownValue() const
Definition: Sema.h:9913
A RAII object to enter scope of a compound statement.
Definition: Sema.h:3715
Stop at code completion.
Definition: Parser.h:1039
virtual bool ValidateCandidate(const TypoCorrection &candidate)
Simple predicate used by the default RankCandidate to determine whether to return an edit distance of...
This represents one expression.
Definition: Expr.h:106
StmtResult StmtEmpty()
Definition: Ownership.h:290
This scope corresponds to an SEH try.
Definition: Scope.h:122
This file defines the classes used to store parsed information about declaration-specifiers and decla...
void SkipMalformedDecl()
SkipMalformedDecl - Read tokens until we get to some likely good stopping point for skipping past a s...
Definition: ParseDecl.cpp:1839
This scope corresponds to an SEH except.
Definition: Scope.h:125
SourceLocation getLocation() const
Return a source location identifier for the specified offset in the current file. ...
Definition: Token.h:124
Initial building of a for-range statement.
Definition: Sema.h:3798
This is a compound statement scope.
Definition: Scope.h:131
Code completion occurs within a statement, which may also be an expression or a declaration.
Definition: Sema.h:10314
A boolean condition, from &#39;if&#39;, &#39;while&#39;, &#39;for&#39;, or &#39;do&#39;.
ConditionKind
Definition: Sema.h:9921
bool isInvalid() const
Definition: Ownership.h:170
bool isUsable() const
Definition: Ownership.h:171
The result type of a method or function.
OpaquePtr< DeclGroupRef > DeclGroupPtrTy
Definition: Parser.h:388
PrettyDeclStackTraceEntry - If a crash occurs in the parser while parsing something related to a decl...
const LangOptions & getLangOpts() const
Definition: Parser.h:372
Kind
Stop skipping at semicolon.
Definition: Parser.h:1036
ActionResult - This structure is used while parsing/acting on expressions, stmts, etc...
Definition: Ownership.h:157
Encodes a location in the source.
bool is(tok::TokenKind Kind) const
Definition: FormatToken.h:307
IdentifierInfo * getIdentifierInfo() const
Definition: Token.h:177
Represents the declaration of a label.
Definition: Decl.h:469
ExtensionRAIIObject - This saves the state of extension warnings when constructed and disables them...
TokenKind
Provides a simple uniform namespace for tokens from all C languages.
Definition: TokenKinds.h:25
Scope * getCurScope() const
Definition: Parser.h:379
We are currently in the filter expression of an SEH except block.
Definition: Scope.h:128
bool isNot(tok::TokenKind K) const
Definition: Token.h:96
Dataflow Directional Tag Classes.
bool isValid() const
Return true if this is a valid SourceLocation object.
ExprResult ParseCaseExpression(SourceLocation CaseLoc)
Definition: ParseExpr.cpp:220
static FixItHint CreateRemoval(CharSourceRange RemoveRange)
Create a code modification hint that removes the given source range.
Definition: Diagnostic.h:118
A constant boolean condition from &#39;if constexpr&#39;.
bool isOneOf(tok::TokenKind K1, tok::TokenKind K2) const
Definition: Token.h:97
This is the scope for a function-level C++ try or catch scope.
Definition: Scope.h:105
DiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID)
Definition: Parser.cpp:73
Expr * ValueExpr
Definition: LoopHint.h:36
static FixItHint CreateInsertion(SourceLocation InsertionLoc, StringRef Code, bool BeforePreviousInsertions=false)
Create a code modification hint that inserts the given code string at a specific location.
Definition: Diagnostic.h:92
This is a scope that can contain a declaration.
Definition: Scope.h:60
StmtResult ProcessStmtAttributes(Stmt *Stmt, const ParsedAttributesView &Attrs, SourceRange Range)
Stmt attributes - this routine is the top level dispatcher.
An integral condition for a &#39;switch&#39; statement.
Captures information about "declaration specifiers".
Definition: DeclSpec.h:228
Code completion occurs at the beginning of the initialization statement (or expression) in a for loop...
Definition: Sema.h:10317
bool isSwitchScope() const
isSwitchScope - Return true if this scope is a switch scope.
Definition: Scope.h:392
SourceLocation ConsumeToken()
ConsumeToken - Consume the current &#39;peek token&#39; and lex the next one.
Definition: Parser.h:417
static FixItHint CreateReplacement(CharSourceRange RemoveRange, StringRef Code)
Create a code modification hint that replaces the given source range with the given code string...
Definition: Diagnostic.h:129
SourceRange Range
Definition: LoopHint.h:23
Annotates a diagnostic with some code that should be inserted, removed, or replaced to fix the proble...
Definition: Diagnostic.h:66
Loop optimization hint for loop and unroll pragmas.
Definition: LoopHint.h:21
A trivial tuple used to represent a source range.
ParsedAttributes - A collection of parsed attributes.
Definition: ParsedAttr.h:855
SourceLocation ColonLoc
Location of &#39;:&#39;.
Definition: OpenMPClause.h:108
An RAII object for [un]poisoning an identifier within a scope.
Stop skipping at specified token, but don&#39;t skip the token itself.
Definition: Parser.h:1038