1//===--- Parser.cpp - C Language Family Parser ----------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file implements the Parser interfaces.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Parse/Parser.h"
15#include "RAIIObjectsForParser.h"
16#include "clang/AST/ASTConsumer.h"
17#include "clang/AST/ASTContext.h"
18#include "clang/AST/DeclTemplate.h"
19#include "clang/Parse/ParseDiagnostic.h"
20#include "clang/Sema/DeclSpec.h"
21#include "clang/Sema/ParsedTemplate.h"
22#include "clang/Sema/Scope.h"
23#include "llvm/Support/raw_ostream.h"
24using namespace clang;
25
26
27namespace {
28/// \brief A comment handler that passes comments found by the preprocessor
29/// to the parser action.
30class ActionCommentHandler : public CommentHandler {
31  Sema &S;
32
33public:
34  explicit ActionCommentHandler(Sema &S) : S(S) { }
35
36  bool HandleComment(Preprocessor &PP, SourceRange Comment) override {
37    S.ActOnComment(Comment);
38    return false;
39  }
40};
41} // end anonymous namespace
42
43IdentifierInfo *Parser::getSEHExceptKeyword() {
44  // __except is accepted as a (contextual) keyword
45  if (!Ident__except && (getLangOpts().MicrosoftExt || getLangOpts().Borland))
46    Ident__except = PP.getIdentifierInfo("__except");
47
48  return Ident__except;
49}
50
51Parser::Parser(Preprocessor &pp, Sema &actions, bool skipFunctionBodies)
52  : PP(pp), Actions(actions), Diags(PP.getDiagnostics()),
53    GreaterThanIsOperator(true), ColonIsSacred(false),
54    InMessageExpression(false), TemplateParameterDepth(0),
55    ParsingInObjCContainer(false) {
56  SkipFunctionBodies = pp.isCodeCompletionEnabled() || skipFunctionBodies;
57  Tok.startToken();
58  Tok.setKind(tok::eof);
59  Actions.CurScope = nullptr;
60  NumCachedScopes = 0;
61  ParenCount = BracketCount = BraceCount = 0;
62  CurParsedObjCImpl = nullptr;
63
64  // Add #pragma handlers. These are removed and destroyed in the
65  // destructor.
66  initializePragmaHandlers();
67
68  CommentSemaHandler.reset(new ActionCommentHandler(actions));
69  PP.addCommentHandler(CommentSemaHandler.get());
70
71  PP.setCodeCompletionHandler(*this);
72}
73
74DiagnosticBuilder Parser::Diag(SourceLocation Loc, unsigned DiagID) {
75  return Diags.Report(Loc, DiagID);
76}
77
78DiagnosticBuilder Parser::Diag(const Token &Tok, unsigned DiagID) {
79  return Diag(Tok.getLocation(), DiagID);
80}
81
82/// \brief Emits a diagnostic suggesting parentheses surrounding a
83/// given range.
84///
85/// \param Loc The location where we'll emit the diagnostic.
86/// \param DK The kind of diagnostic to emit.
87/// \param ParenRange Source range enclosing code that should be parenthesized.
88void Parser::SuggestParentheses(SourceLocation Loc, unsigned DK,
89                                SourceRange ParenRange) {
90  SourceLocation EndLoc = PP.getLocForEndOfToken(ParenRange.getEnd());
91  if (!ParenRange.getEnd().isFileID() || EndLoc.isInvalid()) {
92    // We can't display the parentheses, so just dig the
93    // warning/error and return.
94    Diag(Loc, DK);
95    return;
96  }
97
98  Diag(Loc, DK)
99    << FixItHint::CreateInsertion(ParenRange.getBegin(), "(")
100    << FixItHint::CreateInsertion(EndLoc, ")");
101}
102
103static bool IsCommonTypo(tok::TokenKind ExpectedTok, const Token &Tok) {
104  switch (ExpectedTok) {
105  case tok::semi:
106    return Tok.is(tok::colon) || Tok.is(tok::comma); // : or , for ;
107  default: return false;
108  }
109}
110
111bool Parser::ExpectAndConsume(tok::TokenKind ExpectedTok, unsigned DiagID,
112                              StringRef Msg) {
113  if (Tok.is(ExpectedTok) || Tok.is(tok::code_completion)) {
114    ConsumeAnyToken();
115    return false;
116  }
117
118  // Detect common single-character typos and resume.
119  if (IsCommonTypo(ExpectedTok, Tok)) {
120    SourceLocation Loc = Tok.getLocation();
121    {
122      DiagnosticBuilder DB = Diag(Loc, DiagID);
123      DB << FixItHint::CreateReplacement(
124                SourceRange(Loc), tok::getPunctuatorSpelling(ExpectedTok));
125      if (DiagID == diag::err_expected)
126        DB << ExpectedTok;
127      else if (DiagID == diag::err_expected_after)
128        DB << Msg << ExpectedTok;
129      else
130        DB << Msg;
131    }
132
133    // Pretend there wasn't a problem.
134    ConsumeAnyToken();
135    return false;
136  }
137
138  SourceLocation EndLoc = PP.getLocForEndOfToken(PrevTokLocation);
139  const char *Spelling = nullptr;
140  if (EndLoc.isValid())
141    Spelling = tok::getPunctuatorSpelling(ExpectedTok);
142
143  DiagnosticBuilder DB =
144      Spelling
145          ? Diag(EndLoc, DiagID) << FixItHint::CreateInsertion(EndLoc, Spelling)
146          : Diag(Tok, DiagID);
147  if (DiagID == diag::err_expected)
148    DB << ExpectedTok;
149  else if (DiagID == diag::err_expected_after)
150    DB << Msg << ExpectedTok;
151  else
152    DB << Msg;
153
154  return true;
155}
156
157bool Parser::ExpectAndConsumeSemi(unsigned DiagID) {
158  if (TryConsumeToken(tok::semi))
159    return false;
160
161  if (Tok.is(tok::code_completion)) {
162    handleUnexpectedCodeCompletionToken();
163    return false;
164  }
165
166  if ((Tok.is(tok::r_paren) || Tok.is(tok::r_square)) &&
167      NextToken().is(tok::semi)) {
168    Diag(Tok, diag::err_extraneous_token_before_semi)
169      << PP.getSpelling(Tok)
170      << FixItHint::CreateRemoval(Tok.getLocation());
171    ConsumeAnyToken(); // The ')' or ']'.
172    ConsumeToken(); // The ';'.
173    return false;
174  }
175
176  return ExpectAndConsume(tok::semi, DiagID);
177}
178
179void Parser::ConsumeExtraSemi(ExtraSemiKind Kind, unsigned TST) {
180  if (!Tok.is(tok::semi)) return;
181
182  bool HadMultipleSemis = false;
183  SourceLocation StartLoc = Tok.getLocation();
184  SourceLocation EndLoc = Tok.getLocation();
185  ConsumeToken();
186
187  while ((Tok.is(tok::semi) && !Tok.isAtStartOfLine())) {
188    HadMultipleSemis = true;
189    EndLoc = Tok.getLocation();
190    ConsumeToken();
191  }
192
193  // C++11 allows extra semicolons at namespace scope, but not in any of the
194  // other contexts.
195  if (Kind == OutsideFunction && getLangOpts().CPlusPlus) {
196    if (getLangOpts().CPlusPlus11)
197      Diag(StartLoc, diag::warn_cxx98_compat_top_level_semi)
198          << FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
199    else
200      Diag(StartLoc, diag::ext_extra_semi_cxx11)
201          << FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
202    return;
203  }
204
205  if (Kind != AfterMemberFunctionDefinition || HadMultipleSemis)
206    Diag(StartLoc, diag::ext_extra_semi)
207        << Kind << DeclSpec::getSpecifierName((DeclSpec::TST)TST,
208                                    Actions.getASTContext().getPrintingPolicy())
209        << FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
210  else
211    // A single semicolon is valid after a member function definition.
212    Diag(StartLoc, diag::warn_extra_semi_after_mem_fn_def)
213      << FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
214}
215
216//===----------------------------------------------------------------------===//
217// Error recovery.
218//===----------------------------------------------------------------------===//
219
220static bool HasFlagsSet(Parser::SkipUntilFlags L, Parser::SkipUntilFlags R) {
221  return (static_cast<unsigned>(L) & static_cast<unsigned>(R)) != 0;
222}
223
224/// SkipUntil - Read tokens until we get to the specified token, then consume
225/// it (unless no flag StopBeforeMatch).  Because we cannot guarantee that the
226/// token will ever occur, this skips to the next token, or to some likely
227/// good stopping point.  If StopAtSemi is true, skipping will stop at a ';'
228/// character.
229///
230/// If SkipUntil finds the specified token, it returns true, otherwise it
231/// returns false.
232bool Parser::SkipUntil(ArrayRef<tok::TokenKind> Toks, SkipUntilFlags Flags) {
233  // We always want this function to skip at least one token if the first token
234  // isn't T and if not at EOF.
235  bool isFirstTokenSkipped = true;
236  while (1) {
237    // If we found one of the tokens, stop and return true.
238    for (unsigned i = 0, NumToks = Toks.size(); i != NumToks; ++i) {
239      if (Tok.is(Toks[i])) {
240        if (HasFlagsSet(Flags, StopBeforeMatch)) {
241          // Noop, don't consume the token.
242        } else {
243          ConsumeAnyToken();
244        }
245        return true;
246      }
247    }
248
249    // Important special case: The caller has given up and just wants us to
250    // skip the rest of the file. Do this without recursing, since we can
251    // get here precisely because the caller detected too much recursion.
252    if (Toks.size() == 1 && Toks[0] == tok::eof &&
253        !HasFlagsSet(Flags, StopAtSemi) &&
254        !HasFlagsSet(Flags, StopAtCodeCompletion)) {
255      while (Tok.isNot(tok::eof))
256        ConsumeAnyToken();
257      return true;
258    }
259
260    switch (Tok.getKind()) {
261    case tok::eof:
262      // Ran out of tokens.
263      return false;
264
265    case tok::annot_pragma_openmp_end:
266      // Stop before an OpenMP pragma boundary.
267    case tok::annot_module_begin:
268    case tok::annot_module_end:
269    case tok::annot_module_include:
270      // Stop before we change submodules. They generally indicate a "good"
271      // place to pick up parsing again (except in the special case where
272      // we're trying to skip to EOF).
273      return false;
274
275    case tok::code_completion:
276      if (!HasFlagsSet(Flags, StopAtCodeCompletion))
277        handleUnexpectedCodeCompletionToken();
278      return false;
279
280    case tok::l_paren:
281      // Recursively skip properly-nested parens.
282      ConsumeParen();
283      if (HasFlagsSet(Flags, StopAtCodeCompletion))
284        SkipUntil(tok::r_paren, StopAtCodeCompletion);
285      else
286        SkipUntil(tok::r_paren);
287      break;
288    case tok::l_square:
289      // Recursively skip properly-nested square brackets.
290      ConsumeBracket();
291      if (HasFlagsSet(Flags, StopAtCodeCompletion))
292        SkipUntil(tok::r_square, StopAtCodeCompletion);
293      else
294        SkipUntil(tok::r_square);
295      break;
296    case tok::l_brace:
297      // Recursively skip properly-nested braces.
298      ConsumeBrace();
299      if (HasFlagsSet(Flags, StopAtCodeCompletion))
300        SkipUntil(tok::r_brace, StopAtCodeCompletion);
301      else
302        SkipUntil(tok::r_brace);
303      break;
304
305    // Okay, we found a ']' or '}' or ')', which we think should be balanced.
306    // Since the user wasn't looking for this token (if they were, it would
307    // already be handled), this isn't balanced.  If there is a LHS token at a
308    // higher level, we will assume that this matches the unbalanced token
309    // and return it.  Otherwise, this is a spurious RHS token, which we skip.
310    case tok::r_paren:
311      if (ParenCount && !isFirstTokenSkipped)
312        return false;  // Matches something.
313      ConsumeParen();
314      break;
315    case tok::r_square:
316      if (BracketCount && !isFirstTokenSkipped)
317        return false;  // Matches something.
318      ConsumeBracket();
319      break;
320    case tok::r_brace:
321      if (BraceCount && !isFirstTokenSkipped)
322        return false;  // Matches something.
323      ConsumeBrace();
324      break;
325
326    case tok::string_literal:
327    case tok::wide_string_literal:
328    case tok::utf8_string_literal:
329    case tok::utf16_string_literal:
330    case tok::utf32_string_literal:
331      ConsumeStringToken();
332      break;
333
334    case tok::semi:
335      if (HasFlagsSet(Flags, StopAtSemi))
336        return false;
337      // FALL THROUGH.
338    default:
339      // Skip this token.
340      ConsumeToken();
341      break;
342    }
343    isFirstTokenSkipped = false;
344  }
345}
346
347//===----------------------------------------------------------------------===//
348// Scope manipulation
349//===----------------------------------------------------------------------===//
350
351/// EnterScope - Start a new scope.
352void Parser::EnterScope(unsigned ScopeFlags) {
353  if (NumCachedScopes) {
354    Scope *N = ScopeCache[--NumCachedScopes];
355    N->Init(getCurScope(), ScopeFlags);
356    Actions.CurScope = N;
357  } else {
358    Actions.CurScope = new Scope(getCurScope(), ScopeFlags, Diags);
359  }
360}
361
362/// ExitScope - Pop a scope off the scope stack.
363void Parser::ExitScope() {
364  assert(getCurScope() && "Scope imbalance!");
365
366  // Inform the actions module that this scope is going away if there are any
367  // decls in it.
368  Actions.ActOnPopScope(Tok.getLocation(), getCurScope());
369
370  Scope *OldScope = getCurScope();
371  Actions.CurScope = OldScope->getParent();
372
373  if (NumCachedScopes == ScopeCacheSize)
374    delete OldScope;
375  else
376    ScopeCache[NumCachedScopes++] = OldScope;
377}
378
379/// Set the flags for the current scope to ScopeFlags. If ManageFlags is false,
380/// this object does nothing.
381Parser::ParseScopeFlags::ParseScopeFlags(Parser *Self, unsigned ScopeFlags,
382                                 bool ManageFlags)
383  : CurScope(ManageFlags ? Self->getCurScope() : nullptr) {
384  if (CurScope) {
385    OldFlags = CurScope->getFlags();
386    CurScope->setFlags(ScopeFlags);
387  }
388}
389
390/// Restore the flags for the current scope to what they were before this
391/// object overrode them.
392Parser::ParseScopeFlags::~ParseScopeFlags() {
393  if (CurScope)
394    CurScope->setFlags(OldFlags);
395}
396
397
398//===----------------------------------------------------------------------===//
399// C99 6.9: External Definitions.
400//===----------------------------------------------------------------------===//
401
402Parser::~Parser() {
403  // If we still have scopes active, delete the scope tree.
404  delete getCurScope();
405  Actions.CurScope = nullptr;
406
407  // Free the scope cache.
408  for (unsigned i = 0, e = NumCachedScopes; i != e; ++i)
409    delete ScopeCache[i];
410
411  resetPragmaHandlers();
412
413  PP.removeCommentHandler(CommentSemaHandler.get());
414
415  PP.clearCodeCompletionHandler();
416
417  assert(TemplateIds.empty() && "Still alive TemplateIdAnnotations around?");
418}
419
420/// Initialize - Warm up the parser.
421///
422void Parser::Initialize() {
423  // Create the translation unit scope.  Install it as the current scope.
424  assert(getCurScope() == nullptr && "A scope is already active?");
425  EnterScope(Scope::DeclScope);
426  Actions.ActOnTranslationUnitScope(getCurScope());
427
428  // Initialization for Objective-C context sensitive keywords recognition.
429  // Referenced in Parser::ParseObjCTypeQualifierList.
430  if (getLangOpts().ObjC1) {
431    ObjCTypeQuals[objc_in] = &PP.getIdentifierTable().get("in");
432    ObjCTypeQuals[objc_out] = &PP.getIdentifierTable().get("out");
433    ObjCTypeQuals[objc_inout] = &PP.getIdentifierTable().get("inout");
434    ObjCTypeQuals[objc_oneway] = &PP.getIdentifierTable().get("oneway");
435    ObjCTypeQuals[objc_bycopy] = &PP.getIdentifierTable().get("bycopy");
436    ObjCTypeQuals[objc_byref] = &PP.getIdentifierTable().get("byref");
437  }
438
439  Ident_instancetype = nullptr;
440  Ident_final = nullptr;
441  Ident_sealed = nullptr;
442  Ident_override = nullptr;
443
444  Ident_super = &PP.getIdentifierTable().get("super");
445
446  if (getLangOpts().AltiVec) {
447    Ident_vector = &PP.getIdentifierTable().get("vector");
448    Ident_pixel = &PP.getIdentifierTable().get("pixel");
449    Ident_bool = &PP.getIdentifierTable().get("bool");
450  }
451
452  Ident_introduced = nullptr;
453  Ident_deprecated = nullptr;
454  Ident_obsoleted = nullptr;
455  Ident_unavailable = nullptr;
456
457  Ident__except = nullptr;
458
459  Ident__exception_code = Ident__exception_info = nullptr;
460  Ident__abnormal_termination = Ident___exception_code = nullptr;
461  Ident___exception_info = Ident___abnormal_termination = nullptr;
462  Ident_GetExceptionCode = Ident_GetExceptionInfo = nullptr;
463  Ident_AbnormalTermination = nullptr;
464
465  if(getLangOpts().Borland) {
466    Ident__exception_info        = PP.getIdentifierInfo("_exception_info");
467    Ident___exception_info       = PP.getIdentifierInfo("__exception_info");
468    Ident_GetExceptionInfo       = PP.getIdentifierInfo("GetExceptionInformation");
469    Ident__exception_code        = PP.getIdentifierInfo("_exception_code");
470    Ident___exception_code       = PP.getIdentifierInfo("__exception_code");
471    Ident_GetExceptionCode       = PP.getIdentifierInfo("GetExceptionCode");
472    Ident__abnormal_termination  = PP.getIdentifierInfo("_abnormal_termination");
473    Ident___abnormal_termination = PP.getIdentifierInfo("__abnormal_termination");
474    Ident_AbnormalTermination    = PP.getIdentifierInfo("AbnormalTermination");
475
476    PP.SetPoisonReason(Ident__exception_code,diag::err_seh___except_block);
477    PP.SetPoisonReason(Ident___exception_code,diag::err_seh___except_block);
478    PP.SetPoisonReason(Ident_GetExceptionCode,diag::err_seh___except_block);
479    PP.SetPoisonReason(Ident__exception_info,diag::err_seh___except_filter);
480    PP.SetPoisonReason(Ident___exception_info,diag::err_seh___except_filter);
481    PP.SetPoisonReason(Ident_GetExceptionInfo,diag::err_seh___except_filter);
482    PP.SetPoisonReason(Ident__abnormal_termination,diag::err_seh___finally_block);
483    PP.SetPoisonReason(Ident___abnormal_termination,diag::err_seh___finally_block);
484    PP.SetPoisonReason(Ident_AbnormalTermination,diag::err_seh___finally_block);
485  }
486
487  Actions.Initialize();
488
489  // Prime the lexer look-ahead.
490  ConsumeToken();
491}
492
493namespace {
494  /// \brief RAIIObject to destroy the contents of a SmallVector of
495  /// TemplateIdAnnotation pointers and clear the vector.
496  class DestroyTemplateIdAnnotationsRAIIObj {
497    SmallVectorImpl<TemplateIdAnnotation *> &Container;
498  public:
499    DestroyTemplateIdAnnotationsRAIIObj(SmallVectorImpl<TemplateIdAnnotation *>
500                                       &Container)
501      : Container(Container) {}
502
503    ~DestroyTemplateIdAnnotationsRAIIObj() {
504      for (SmallVectorImpl<TemplateIdAnnotation *>::iterator I =
505           Container.begin(), E = Container.end();
506           I != E; ++I)
507        (*I)->Destroy();
508      Container.clear();
509    }
510  };
511}
512
513void Parser::LateTemplateParserCleanupCallback(void *P) {
514  // While this RAII helper doesn't bracket any actual work, the destructor will
515  // clean up annotations that were created during ActOnEndOfTranslationUnit
516  // when incremental processing is enabled.
517  DestroyTemplateIdAnnotationsRAIIObj CleanupRAII(((Parser *)P)->TemplateIds);
518}
519
520/// ParseTopLevelDecl - Parse one top-level declaration, return whatever the
521/// action tells us to.  This returns true if the EOF was encountered.
522bool Parser::ParseTopLevelDecl(DeclGroupPtrTy &Result) {
523  DestroyTemplateIdAnnotationsRAIIObj CleanupRAII(TemplateIds);
524
525  // Skip over the EOF token, flagging end of previous input for incremental
526  // processing
527  if (PP.isIncrementalProcessingEnabled() && Tok.is(tok::eof))
528    ConsumeToken();
529
530  Result = DeclGroupPtrTy();
531  switch (Tok.getKind()) {
532  case tok::annot_pragma_unused:
533    HandlePragmaUnused();
534    return false;
535
536  case tok::annot_module_include:
537    Actions.ActOnModuleInclude(Tok.getLocation(),
538                               reinterpret_cast<Module *>(
539                                   Tok.getAnnotationValue()));
540    ConsumeToken();
541    return false;
542
543  case tok::annot_module_begin:
544  case tok::annot_module_end:
545    // FIXME: Update visibility based on the submodule we're in.
546    ConsumeToken();
547    return false;
548
549  case tok::eof:
550    // Late template parsing can begin.
551    if (getLangOpts().DelayedTemplateParsing)
552      Actions.SetLateTemplateParser(LateTemplateParserCallback,
553                                    PP.isIncrementalProcessingEnabled() ?
554                                    LateTemplateParserCleanupCallback : nullptr,
555                                    this);
556    if (!PP.isIncrementalProcessingEnabled())
557      Actions.ActOnEndOfTranslationUnit();
558    //else don't tell Sema that we ended parsing: more input might come.
559    return true;
560
561  default:
562    break;
563  }
564
565  ParsedAttributesWithRange attrs(AttrFactory);
566  MaybeParseCXX11Attributes(attrs);
567  MaybeParseMicrosoftAttributes(attrs);
568
569  Result = ParseExternalDeclaration(attrs);
570  return false;
571}
572
573/// ParseExternalDeclaration:
574///
575///       external-declaration: [C99 6.9], declaration: [C++ dcl.dcl]
576///         function-definition
577///         declaration
578/// [GNU]   asm-definition
579/// [GNU]   __extension__ external-declaration
580/// [OBJC]  objc-class-definition
581/// [OBJC]  objc-class-declaration
582/// [OBJC]  objc-alias-declaration
583/// [OBJC]  objc-protocol-definition
584/// [OBJC]  objc-method-definition
585/// [OBJC]  @end
586/// [C++]   linkage-specification
587/// [GNU] asm-definition:
588///         simple-asm-expr ';'
589/// [C++11] empty-declaration
590/// [C++11] attribute-declaration
591///
592/// [C++11] empty-declaration:
593///           ';'
594///
595/// [C++0x/GNU] 'extern' 'template' declaration
596Parser::DeclGroupPtrTy
597Parser::ParseExternalDeclaration(ParsedAttributesWithRange &attrs,
598                                 ParsingDeclSpec *DS) {
599  DestroyTemplateIdAnnotationsRAIIObj CleanupRAII(TemplateIds);
600  ParenBraceBracketBalancer BalancerRAIIObj(*this);
601
602  if (PP.isCodeCompletionReached()) {
603    cutOffParsing();
604    return DeclGroupPtrTy();
605  }
606
607  Decl *SingleDecl = nullptr;
608  switch (Tok.getKind()) {
609  case tok::annot_pragma_vis:
610    HandlePragmaVisibility();
611    return DeclGroupPtrTy();
612  case tok::annot_pragma_pack:
613    HandlePragmaPack();
614    return DeclGroupPtrTy();
615  case tok::annot_pragma_msstruct:
616    HandlePragmaMSStruct();
617    return DeclGroupPtrTy();
618  case tok::annot_pragma_align:
619    HandlePragmaAlign();
620    return DeclGroupPtrTy();
621  case tok::annot_pragma_weak:
622    HandlePragmaWeak();
623    return DeclGroupPtrTy();
624  case tok::annot_pragma_weakalias:
625    HandlePragmaWeakAlias();
626    return DeclGroupPtrTy();
627  case tok::annot_pragma_redefine_extname:
628    HandlePragmaRedefineExtname();
629    return DeclGroupPtrTy();
630  case tok::annot_pragma_fp_contract:
631    HandlePragmaFPContract();
632    return DeclGroupPtrTy();
633  case tok::annot_pragma_opencl_extension:
634    HandlePragmaOpenCLExtension();
635    return DeclGroupPtrTy();
636  case tok::annot_pragma_openmp:
637    return ParseOpenMPDeclarativeDirective();
638  case tok::annot_pragma_ms_pointers_to_members:
639    HandlePragmaMSPointersToMembers();
640    return DeclGroupPtrTy();
641  case tok::annot_pragma_ms_vtordisp:
642    HandlePragmaMSVtorDisp();
643    return DeclGroupPtrTy();
644  case tok::annot_pragma_ms_pragma:
645    HandlePragmaMSPragma();
646    return DeclGroupPtrTy();
647  case tok::semi:
648    // Either a C++11 empty-declaration or attribute-declaration.
649    SingleDecl = Actions.ActOnEmptyDeclaration(getCurScope(),
650                                               attrs.getList(),
651                                               Tok.getLocation());
652    ConsumeExtraSemi(OutsideFunction);
653    break;
654  case tok::r_brace:
655    Diag(Tok, diag::err_extraneous_closing_brace);
656    ConsumeBrace();
657    return DeclGroupPtrTy();
658  case tok::eof:
659    Diag(Tok, diag::err_expected_external_declaration);
660    return DeclGroupPtrTy();
661  case tok::kw___extension__: {
662    // __extension__ silences extension warnings in the subexpression.
663    ExtensionRAIIObject O(Diags);  // Use RAII to do this.
664    ConsumeToken();
665    return ParseExternalDeclaration(attrs);
666  }
667  case tok::kw_asm: {
668    ProhibitAttributes(attrs);
669
670    SourceLocation StartLoc = Tok.getLocation();
671    SourceLocation EndLoc;
672    ExprResult Result(ParseSimpleAsm(&EndLoc));
673
674    ExpectAndConsume(tok::semi, diag::err_expected_after,
675                     "top-level asm block");
676
677    if (Result.isInvalid())
678      return DeclGroupPtrTy();
679    SingleDecl = Actions.ActOnFileScopeAsmDecl(Result.get(), StartLoc, EndLoc);
680    break;
681  }
682  case tok::at:
683    return ParseObjCAtDirectives();
684  case tok::minus:
685  case tok::plus:
686    if (!getLangOpts().ObjC1) {
687      Diag(Tok, diag::err_expected_external_declaration);
688      ConsumeToken();
689      return DeclGroupPtrTy();
690    }
691    SingleDecl = ParseObjCMethodDefinition();
692    break;
693  case tok::code_completion:
694      Actions.CodeCompleteOrdinaryName(getCurScope(),
695                             CurParsedObjCImpl? Sema::PCC_ObjCImplementation
696                                              : Sema::PCC_Namespace);
697    cutOffParsing();
698    return DeclGroupPtrTy();
699  case tok::kw_using:
700  case tok::kw_namespace:
701  case tok::kw_typedef:
702  case tok::kw_template:
703  case tok::kw_export:    // As in 'export template'
704  case tok::kw_static_assert:
705  case tok::kw__Static_assert:
706    // A function definition cannot start with any of these keywords.
707    {
708      SourceLocation DeclEnd;
709      return ParseDeclaration(Declarator::FileContext, DeclEnd, attrs);
710    }
711
712  case tok::kw_static:
713    // Parse (then ignore) 'static' prior to a template instantiation. This is
714    // a GCC extension that we intentionally do not support.
715    if (getLangOpts().CPlusPlus && NextToken().is(tok::kw_template)) {
716      Diag(ConsumeToken(), diag::warn_static_inline_explicit_inst_ignored)
717        << 0;
718      SourceLocation DeclEnd;
719      return ParseDeclaration(Declarator::FileContext, DeclEnd, attrs);
720    }
721    goto dont_know;
722
723  case tok::kw_inline:
724    if (getLangOpts().CPlusPlus) {
725      tok::TokenKind NextKind = NextToken().getKind();
726
727      // Inline namespaces. Allowed as an extension even in C++03.
728      if (NextKind == tok::kw_namespace) {
729        SourceLocation DeclEnd;
730        return ParseDeclaration(Declarator::FileContext, DeclEnd, attrs);
731      }
732
733      // Parse (then ignore) 'inline' prior to a template instantiation. This is
734      // a GCC extension that we intentionally do not support.
735      if (NextKind == tok::kw_template) {
736        Diag(ConsumeToken(), diag::warn_static_inline_explicit_inst_ignored)
737          << 1;
738        SourceLocation DeclEnd;
739        return ParseDeclaration(Declarator::FileContext, DeclEnd, attrs);
740      }
741    }
742    goto dont_know;
743
744  case tok::kw_extern:
745    if (getLangOpts().CPlusPlus && NextToken().is(tok::kw_template)) {
746      // Extern templates
747      SourceLocation ExternLoc = ConsumeToken();
748      SourceLocation TemplateLoc = ConsumeToken();
749      Diag(ExternLoc, getLangOpts().CPlusPlus11 ?
750             diag::warn_cxx98_compat_extern_template :
751             diag::ext_extern_template) << SourceRange(ExternLoc, TemplateLoc);
752      SourceLocation DeclEnd;
753      return Actions.ConvertDeclToDeclGroup(
754                  ParseExplicitInstantiation(Declarator::FileContext,
755                                             ExternLoc, TemplateLoc, DeclEnd));
756    }
757    goto dont_know;
758
759  case tok::kw___if_exists:
760  case tok::kw___if_not_exists:
761    ParseMicrosoftIfExistsExternalDeclaration();
762    return DeclGroupPtrTy();
763
764  default:
765  dont_know:
766    // We can't tell whether this is a function-definition or declaration yet.
767    return ParseDeclarationOrFunctionDefinition(attrs, DS);
768  }
769
770  // This routine returns a DeclGroup, if the thing we parsed only contains a
771  // single decl, convert it now.
772  return Actions.ConvertDeclToDeclGroup(SingleDecl);
773}
774
775/// \brief Determine whether the current token, if it occurs after a
776/// declarator, continues a declaration or declaration list.
777bool Parser::isDeclarationAfterDeclarator() {
778  // Check for '= delete' or '= default'
779  if (getLangOpts().CPlusPlus && Tok.is(tok::equal)) {
780    const Token &KW = NextToken();
781    if (KW.is(tok::kw_default) || KW.is(tok::kw_delete))
782      return false;
783  }
784
785  return Tok.is(tok::equal) ||      // int X()=  -> not a function def
786    Tok.is(tok::comma) ||           // int X(),  -> not a function def
787    Tok.is(tok::semi)  ||           // int X();  -> not a function def
788    Tok.is(tok::kw_asm) ||          // int X() __asm__ -> not a function def
789    Tok.is(tok::kw___attribute) ||  // int X() __attr__ -> not a function def
790    (getLangOpts().CPlusPlus &&
791     Tok.is(tok::l_paren));         // int X(0) -> not a function def [C++]
792}
793
794/// \brief Determine whether the current token, if it occurs after a
795/// declarator, indicates the start of a function definition.
796bool Parser::isStartOfFunctionDefinition(const ParsingDeclarator &Declarator) {
797  assert(Declarator.isFunctionDeclarator() && "Isn't a function declarator");
798  if (Tok.is(tok::l_brace))   // int X() {}
799    return true;
800
801  // Handle K&R C argument lists: int X(f) int f; {}
802  if (!getLangOpts().CPlusPlus &&
803      Declarator.getFunctionTypeInfo().isKNRPrototype())
804    return isDeclarationSpecifier();
805
806  if (getLangOpts().CPlusPlus && Tok.is(tok::equal)) {
807    const Token &KW = NextToken();
808    return KW.is(tok::kw_default) || KW.is(tok::kw_delete);
809  }
810
811  return Tok.is(tok::colon) ||         // X() : Base() {} (used for ctors)
812         Tok.is(tok::kw_try);          // X() try { ... }
813}
814
815/// ParseDeclarationOrFunctionDefinition - Parse either a function-definition or
816/// a declaration.  We can't tell which we have until we read up to the
817/// compound-statement in function-definition. TemplateParams, if
818/// non-NULL, provides the template parameters when we're parsing a
819/// C++ template-declaration.
820///
821///       function-definition: [C99 6.9.1]
822///         decl-specs      declarator declaration-list[opt] compound-statement
823/// [C90] function-definition: [C99 6.7.1] - implicit int result
824/// [C90]   decl-specs[opt] declarator declaration-list[opt] compound-statement
825///
826///       declaration: [C99 6.7]
827///         declaration-specifiers init-declarator-list[opt] ';'
828/// [!C99]  init-declarator-list ';'                   [TODO: warn in c99 mode]
829/// [OMP]   threadprivate-directive                              [TODO]
830///
831Parser::DeclGroupPtrTy
832Parser::ParseDeclOrFunctionDefInternal(ParsedAttributesWithRange &attrs,
833                                       ParsingDeclSpec &DS,
834                                       AccessSpecifier AS) {
835  // Parse the common declaration-specifiers piece.
836  ParseDeclarationSpecifiers(DS, ParsedTemplateInfo(), AS, DSC_top_level);
837
838  // If we had a free-standing type definition with a missing semicolon, we
839  // may get this far before the problem becomes obvious.
840  if (DS.hasTagDefinition() &&
841      DiagnoseMissingSemiAfterTagDefinition(DS, AS, DSC_top_level))
842    return DeclGroupPtrTy();
843
844  // C99 6.7.2.3p6: Handle "struct-or-union identifier;", "enum { X };"
845  // declaration-specifiers init-declarator-list[opt] ';'
846  if (Tok.is(tok::semi)) {
847    ProhibitAttributes(attrs);
848    ConsumeToken();
849    Decl *TheDecl = Actions.ParsedFreeStandingDeclSpec(getCurScope(), AS, DS);
850    DS.complete(TheDecl);
851    return Actions.ConvertDeclToDeclGroup(TheDecl);
852  }
853
854  DS.takeAttributesFrom(attrs);
855
856  // ObjC2 allows prefix attributes on class interfaces and protocols.
857  // FIXME: This still needs better diagnostics. We should only accept
858  // attributes here, no types, etc.
859  if (getLangOpts().ObjC2 && Tok.is(tok::at)) {
860    SourceLocation AtLoc = ConsumeToken(); // the "@"
861    if (!Tok.isObjCAtKeyword(tok::objc_interface) &&
862        !Tok.isObjCAtKeyword(tok::objc_protocol)) {
863      Diag(Tok, diag::err_objc_unexpected_attr);
864      SkipUntil(tok::semi); // FIXME: better skip?
865      return DeclGroupPtrTy();
866    }
867
868    DS.abort();
869
870    const char *PrevSpec = nullptr;
871    unsigned DiagID;
872    if (DS.SetTypeSpecType(DeclSpec::TST_unspecified, AtLoc, PrevSpec, DiagID,
873                           Actions.getASTContext().getPrintingPolicy()))
874      Diag(AtLoc, DiagID) << PrevSpec;
875
876    if (Tok.isObjCAtKeyword(tok::objc_protocol))
877      return ParseObjCAtProtocolDeclaration(AtLoc, DS.getAttributes());
878
879    return Actions.ConvertDeclToDeclGroup(
880            ParseObjCAtInterfaceDeclaration(AtLoc, DS.getAttributes()));
881  }
882
883  // If the declspec consisted only of 'extern' and we have a string
884  // literal following it, this must be a C++ linkage specifier like
885  // 'extern "C"'.
886  if (getLangOpts().CPlusPlus && isTokenStringLiteral() &&
887      DS.getStorageClassSpec() == DeclSpec::SCS_extern &&
888      DS.getParsedSpecifiers() == DeclSpec::PQ_StorageClassSpecifier) {
889    Decl *TheDecl = ParseLinkage(DS, Declarator::FileContext);
890    return Actions.ConvertDeclToDeclGroup(TheDecl);
891  }
892
893  return ParseDeclGroup(DS, Declarator::FileContext);
894}
895
896Parser::DeclGroupPtrTy
897Parser::ParseDeclarationOrFunctionDefinition(ParsedAttributesWithRange &attrs,
898                                             ParsingDeclSpec *DS,
899                                             AccessSpecifier AS) {
900  if (DS) {
901    return ParseDeclOrFunctionDefInternal(attrs, *DS, AS);
902  } else {
903    ParsingDeclSpec PDS(*this);
904    // Must temporarily exit the objective-c container scope for
905    // parsing c constructs and re-enter objc container scope
906    // afterwards.
907    ObjCDeclContextSwitch ObjCDC(*this);
908
909    return ParseDeclOrFunctionDefInternal(attrs, PDS, AS);
910  }
911}
912
913/// ParseFunctionDefinition - We parsed and verified that the specified
914/// Declarator is well formed.  If this is a K&R-style function, read the
915/// parameters declaration-list, then start the compound-statement.
916///
917///       function-definition: [C99 6.9.1]
918///         decl-specs      declarator declaration-list[opt] compound-statement
919/// [C90] function-definition: [C99 6.7.1] - implicit int result
920/// [C90]   decl-specs[opt] declarator declaration-list[opt] compound-statement
921/// [C++] function-definition: [C++ 8.4]
922///         decl-specifier-seq[opt] declarator ctor-initializer[opt]
923///         function-body
924/// [C++] function-definition: [C++ 8.4]
925///         decl-specifier-seq[opt] declarator function-try-block
926///
927Decl *Parser::ParseFunctionDefinition(ParsingDeclarator &D,
928                                      const ParsedTemplateInfo &TemplateInfo,
929                                      LateParsedAttrList *LateParsedAttrs) {
930  // Poison SEH identifiers so they are flagged as illegal in function bodies.
931  PoisonSEHIdentifiersRAIIObject PoisonSEHIdentifiers(*this, true);
932  const DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
933
934  // If this is C90 and the declspecs were completely missing, fudge in an
935  // implicit int.  We do this here because this is the only place where
936  // declaration-specifiers are completely optional in the grammar.
937  if (getLangOpts().ImplicitInt && D.getDeclSpec().isEmpty()) {
938    const char *PrevSpec;
939    unsigned DiagID;
940    const PrintingPolicy &Policy = Actions.getASTContext().getPrintingPolicy();
941    D.getMutableDeclSpec().SetTypeSpecType(DeclSpec::TST_int,
942                                           D.getIdentifierLoc(),
943                                           PrevSpec, DiagID,
944                                           Policy);
945    D.SetRangeBegin(D.getDeclSpec().getSourceRange().getBegin());
946  }
947
948  // If this declaration was formed with a K&R-style identifier list for the
949  // arguments, parse declarations for all of the args next.
950  // int foo(a,b) int a; float b; {}
951  if (FTI.isKNRPrototype())
952    ParseKNRParamDeclarations(D);
953
954  // We should have either an opening brace or, in a C++ constructor,
955  // we may have a colon.
956  if (Tok.isNot(tok::l_brace) &&
957      (!getLangOpts().CPlusPlus ||
958       (Tok.isNot(tok::colon) && Tok.isNot(tok::kw_try) &&
959        Tok.isNot(tok::equal)))) {
960    Diag(Tok, diag::err_expected_fn_body);
961
962    // Skip over garbage, until we get to '{'.  Don't eat the '{'.
963    SkipUntil(tok::l_brace, StopAtSemi | StopBeforeMatch);
964
965    // If we didn't find the '{', bail out.
966    if (Tok.isNot(tok::l_brace))
967      return nullptr;
968  }
969
970  // Check to make sure that any normal attributes are allowed to be on
971  // a definition.  Late parsed attributes are checked at the end.
972  if (Tok.isNot(tok::equal)) {
973    AttributeList *DtorAttrs = D.getAttributes();
974    while (DtorAttrs) {
975      if (DtorAttrs->isKnownToGCC() &&
976          !DtorAttrs->isCXX11Attribute()) {
977        Diag(DtorAttrs->getLoc(), diag::warn_attribute_on_function_definition)
978          << DtorAttrs->getName();
979      }
980      DtorAttrs = DtorAttrs->getNext();
981    }
982  }
983
984  // In delayed template parsing mode, for function template we consume the
985  // tokens and store them for late parsing at the end of the translation unit.
986  if (getLangOpts().DelayedTemplateParsing && Tok.isNot(tok::equal) &&
987      TemplateInfo.Kind == ParsedTemplateInfo::Template &&
988      Actions.canDelayFunctionBody(D)) {
989    MultiTemplateParamsArg TemplateParameterLists(*TemplateInfo.TemplateParams);
990
991    ParseScope BodyScope(this, Scope::FnScope|Scope::DeclScope);
992    Scope *ParentScope = getCurScope()->getParent();
993
994    D.setFunctionDefinitionKind(FDK_Definition);
995    Decl *DP = Actions.HandleDeclarator(ParentScope, D,
996                                        TemplateParameterLists);
997    D.complete(DP);
998    D.getMutableDeclSpec().abort();
999
1000    CachedTokens Toks;
1001    LexTemplateFunctionForLateParsing(Toks);
1002
1003    if (DP) {
1004      FunctionDecl *FnD = DP->getAsFunction();
1005      Actions.CheckForFunctionRedefinition(FnD);
1006      Actions.MarkAsLateParsedTemplate(FnD, DP, Toks);
1007    }
1008    return DP;
1009  }
1010  else if (CurParsedObjCImpl &&
1011           !TemplateInfo.TemplateParams &&
1012           (Tok.is(tok::l_brace) || Tok.is(tok::kw_try) ||
1013            Tok.is(tok::colon)) &&
1014      Actions.CurContext->isTranslationUnit()) {
1015    ParseScope BodyScope(this, Scope::FnScope|Scope::DeclScope);
1016    Scope *ParentScope = getCurScope()->getParent();
1017
1018    D.setFunctionDefinitionKind(FDK_Definition);
1019    Decl *FuncDecl = Actions.HandleDeclarator(ParentScope, D,
1020                                              MultiTemplateParamsArg());
1021    D.complete(FuncDecl);
1022    D.getMutableDeclSpec().abort();
1023    if (FuncDecl) {
1024      // Consume the tokens and store them for later parsing.
1025      StashAwayMethodOrFunctionBodyTokens(FuncDecl);
1026      CurParsedObjCImpl->HasCFunction = true;
1027      return FuncDecl;
1028    }
1029    // FIXME: Should we really fall through here?
1030  }
1031
1032  // Enter a scope for the function body.
1033  ParseScope BodyScope(this, Scope::FnScope|Scope::DeclScope);
1034
1035  // Tell the actions module that we have entered a function definition with the
1036  // specified Declarator for the function.
1037  Decl *Res = TemplateInfo.TemplateParams?
1038      Actions.ActOnStartOfFunctionTemplateDef(getCurScope(),
1039                                              *TemplateInfo.TemplateParams, D)
1040    : Actions.ActOnStartOfFunctionDef(getCurScope(), D);
1041
1042  // Break out of the ParsingDeclarator context before we parse the body.
1043  D.complete(Res);
1044
1045  // Break out of the ParsingDeclSpec context, too.  This const_cast is
1046  // safe because we're always the sole owner.
1047  D.getMutableDeclSpec().abort();
1048
1049  if (TryConsumeToken(tok::equal)) {
1050    assert(getLangOpts().CPlusPlus && "Only C++ function definitions have '='");
1051
1052    bool Delete = false;
1053    SourceLocation KWLoc;
1054    if (TryConsumeToken(tok::kw_delete, KWLoc)) {
1055      Diag(KWLoc, getLangOpts().CPlusPlus11
1056                      ? diag::warn_cxx98_compat_deleted_function
1057                      : diag::ext_deleted_function);
1058      Actions.SetDeclDeleted(Res, KWLoc);
1059      Delete = true;
1060    } else if (TryConsumeToken(tok::kw_default, KWLoc)) {
1061      Diag(KWLoc, getLangOpts().CPlusPlus11
1062                      ? diag::warn_cxx98_compat_defaulted_function
1063                      : diag::ext_defaulted_function);
1064      Actions.SetDeclDefaulted(Res, KWLoc);
1065    } else {
1066      llvm_unreachable("function definition after = not 'delete' or 'default'");
1067    }
1068
1069    if (Tok.is(tok::comma)) {
1070      Diag(KWLoc, diag::err_default_delete_in_multiple_declaration)
1071        << Delete;
1072      SkipUntil(tok::semi);
1073    } else if (ExpectAndConsume(tok::semi, diag::err_expected_after,
1074                                Delete ? "delete" : "default")) {
1075      SkipUntil(tok::semi);
1076    }
1077
1078    Stmt *GeneratedBody = Res ? Res->getBody() : nullptr;
1079    Actions.ActOnFinishFunctionBody(Res, GeneratedBody, false);
1080    return Res;
1081  }
1082
1083  if (Tok.is(tok::kw_try))
1084    return ParseFunctionTryBlock(Res, BodyScope);
1085
1086  // If we have a colon, then we're probably parsing a C++
1087  // ctor-initializer.
1088  if (Tok.is(tok::colon)) {
1089    ParseConstructorInitializer(Res);
1090
1091    // Recover from error.
1092    if (!Tok.is(tok::l_brace)) {
1093      BodyScope.Exit();
1094      Actions.ActOnFinishFunctionBody(Res, nullptr);
1095      return Res;
1096    }
1097  } else
1098    Actions.ActOnDefaultCtorInitializers(Res);
1099
1100  // Late attributes are parsed in the same scope as the function body.
1101  if (LateParsedAttrs)
1102    ParseLexedAttributeList(*LateParsedAttrs, Res, false, true);
1103
1104  return ParseFunctionStatementBody(Res, BodyScope);
1105}
1106
1107/// ParseKNRParamDeclarations - Parse 'declaration-list[opt]' which provides
1108/// types for a function with a K&R-style identifier list for arguments.
1109void Parser::ParseKNRParamDeclarations(Declarator &D) {
1110  // We know that the top-level of this declarator is a function.
1111  DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
1112
1113  // Enter function-declaration scope, limiting any declarators to the
1114  // function prototype scope, including parameter declarators.
1115  ParseScope PrototypeScope(this, Scope::FunctionPrototypeScope |
1116                            Scope::FunctionDeclarationScope | Scope::DeclScope);
1117
1118  // Read all the argument declarations.
1119  while (isDeclarationSpecifier()) {
1120    SourceLocation DSStart = Tok.getLocation();
1121
1122    // Parse the common declaration-specifiers piece.
1123    DeclSpec DS(AttrFactory);
1124    ParseDeclarationSpecifiers(DS);
1125
1126    // C99 6.9.1p6: 'each declaration in the declaration list shall have at
1127    // least one declarator'.
1128    // NOTE: GCC just makes this an ext-warn.  It's not clear what it does with
1129    // the declarations though.  It's trivial to ignore them, really hard to do
1130    // anything else with them.
1131    if (TryConsumeToken(tok::semi)) {
1132      Diag(DSStart, diag::err_declaration_does_not_declare_param);
1133      continue;
1134    }
1135
1136    // C99 6.9.1p6: Declarations shall contain no storage-class specifiers other
1137    // than register.
1138    if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified &&
1139        DS.getStorageClassSpec() != DeclSpec::SCS_register) {
1140      Diag(DS.getStorageClassSpecLoc(),
1141           diag::err_invalid_storage_class_in_func_decl);
1142      DS.ClearStorageClassSpecs();
1143    }
1144    if (DS.getThreadStorageClassSpec() != DeclSpec::TSCS_unspecified) {
1145      Diag(DS.getThreadStorageClassSpecLoc(),
1146           diag::err_invalid_storage_class_in_func_decl);
1147      DS.ClearStorageClassSpecs();
1148    }
1149
1150    // Parse the first declarator attached to this declspec.
1151    Declarator ParmDeclarator(DS, Declarator::KNRTypeListContext);
1152    ParseDeclarator(ParmDeclarator);
1153
1154    // Handle the full declarator list.
1155    while (1) {
1156      // If attributes are present, parse them.
1157      MaybeParseGNUAttributes(ParmDeclarator);
1158
1159      // Ask the actions module to compute the type for this declarator.
1160      Decl *Param =
1161        Actions.ActOnParamDeclarator(getCurScope(), ParmDeclarator);
1162
1163      if (Param &&
1164          // A missing identifier has already been diagnosed.
1165          ParmDeclarator.getIdentifier()) {
1166
1167        // Scan the argument list looking for the correct param to apply this
1168        // type.
1169        for (unsigned i = 0; ; ++i) {
1170          // C99 6.9.1p6: those declarators shall declare only identifiers from
1171          // the identifier list.
1172          if (i == FTI.NumParams) {
1173            Diag(ParmDeclarator.getIdentifierLoc(), diag::err_no_matching_param)
1174              << ParmDeclarator.getIdentifier();
1175            break;
1176          }
1177
1178          if (FTI.Params[i].Ident == ParmDeclarator.getIdentifier()) {
1179            // Reject redefinitions of parameters.
1180            if (FTI.Params[i].Param) {
1181              Diag(ParmDeclarator.getIdentifierLoc(),
1182                   diag::err_param_redefinition)
1183                 << ParmDeclarator.getIdentifier();
1184            } else {
1185              FTI.Params[i].Param = Param;
1186            }
1187            break;
1188          }
1189        }
1190      }
1191
1192      // If we don't have a comma, it is either the end of the list (a ';') or
1193      // an error, bail out.
1194      if (Tok.isNot(tok::comma))
1195        break;
1196
1197      ParmDeclarator.clear();
1198
1199      // Consume the comma.
1200      ParmDeclarator.setCommaLoc(ConsumeToken());
1201
1202      // Parse the next declarator.
1203      ParseDeclarator(ParmDeclarator);
1204    }
1205
1206    // Consume ';' and continue parsing.
1207    if (!ExpectAndConsumeSemi(diag::err_expected_semi_declaration))
1208      continue;
1209
1210    // Otherwise recover by skipping to next semi or mandatory function body.
1211    if (SkipUntil(tok::l_brace, StopAtSemi | StopBeforeMatch))
1212      break;
1213    TryConsumeToken(tok::semi);
1214  }
1215
1216  // The actions module must verify that all arguments were declared.
1217  Actions.ActOnFinishKNRParamDeclarations(getCurScope(), D, Tok.getLocation());
1218}
1219
1220
1221/// ParseAsmStringLiteral - This is just a normal string-literal, but is not
1222/// allowed to be a wide string, and is not subject to character translation.
1223///
1224/// [GNU] asm-string-literal:
1225///         string-literal
1226///
1227ExprResult Parser::ParseAsmStringLiteral() {
1228  if (!isTokenStringLiteral()) {
1229    Diag(Tok, diag::err_expected_string_literal)
1230      << /*Source='in...'*/0 << "'asm'";
1231    return ExprError();
1232  }
1233
1234  ExprResult AsmString(ParseStringLiteralExpression());
1235  if (!AsmString.isInvalid()) {
1236    const auto *SL = cast<StringLiteral>(AsmString.get());
1237    if (!SL->isAscii()) {
1238      Diag(Tok, diag::err_asm_operand_wide_string_literal)
1239        << SL->isWide()
1240        << SL->getSourceRange();
1241      return ExprError();
1242    }
1243  }
1244  return AsmString;
1245}
1246
1247/// ParseSimpleAsm
1248///
1249/// [GNU] simple-asm-expr:
1250///         'asm' '(' asm-string-literal ')'
1251///
1252ExprResult Parser::ParseSimpleAsm(SourceLocation *EndLoc) {
1253  assert(Tok.is(tok::kw_asm) && "Not an asm!");
1254  SourceLocation Loc = ConsumeToken();
1255
1256  if (Tok.is(tok::kw_volatile)) {
1257    // Remove from the end of 'asm' to the end of 'volatile'.
1258    SourceRange RemovalRange(PP.getLocForEndOfToken(Loc),
1259                             PP.getLocForEndOfToken(Tok.getLocation()));
1260
1261    Diag(Tok, diag::warn_file_asm_volatile)
1262      << FixItHint::CreateRemoval(RemovalRange);
1263    ConsumeToken();
1264  }
1265
1266  BalancedDelimiterTracker T(*this, tok::l_paren);
1267  if (T.consumeOpen()) {
1268    Diag(Tok, diag::err_expected_lparen_after) << "asm";
1269    return ExprError();
1270  }
1271
1272  ExprResult Result(ParseAsmStringLiteral());
1273
1274  if (!Result.isInvalid()) {
1275    // Close the paren and get the location of the end bracket
1276    T.consumeClose();
1277    if (EndLoc)
1278      *EndLoc = T.getCloseLocation();
1279  } else if (SkipUntil(tok::r_paren, StopAtSemi | StopBeforeMatch)) {
1280    if (EndLoc)
1281      *EndLoc = Tok.getLocation();
1282    ConsumeParen();
1283  }
1284
1285  return Result;
1286}
1287
1288/// \brief Get the TemplateIdAnnotation from the token and put it in the
1289/// cleanup pool so that it gets destroyed when parsing the current top level
1290/// declaration is finished.
1291TemplateIdAnnotation *Parser::takeTemplateIdAnnotation(const Token &tok) {
1292  assert(tok.is(tok::annot_template_id) && "Expected template-id token");
1293  TemplateIdAnnotation *
1294      Id = static_cast<TemplateIdAnnotation *>(tok.getAnnotationValue());
1295  return Id;
1296}
1297
1298void Parser::AnnotateScopeToken(CXXScopeSpec &SS, bool IsNewAnnotation) {
1299  // Push the current token back into the token stream (or revert it if it is
1300  // cached) and use an annotation scope token for current token.
1301  if (PP.isBacktrackEnabled())
1302    PP.RevertCachedTokens(1);
1303  else
1304    PP.EnterToken(Tok);
1305  Tok.setKind(tok::annot_cxxscope);
1306  Tok.setAnnotationValue(Actions.SaveNestedNameSpecifierAnnotation(SS));
1307  Tok.setAnnotationRange(SS.getRange());
1308
1309  // In case the tokens were cached, have Preprocessor replace them
1310  // with the annotation token.  We don't need to do this if we've
1311  // just reverted back to a prior state.
1312  if (IsNewAnnotation)
1313    PP.AnnotateCachedTokens(Tok);
1314}
1315
1316/// \brief Attempt to classify the name at the current token position. This may
1317/// form a type, scope or primary expression annotation, or replace the token
1318/// with a typo-corrected keyword. This is only appropriate when the current
1319/// name must refer to an entity which has already been declared.
1320///
1321/// \param IsAddressOfOperand Must be \c true if the name is preceded by an '&'
1322///        and might possibly have a dependent nested name specifier.
1323/// \param CCC Indicates how to perform typo-correction for this name. If NULL,
1324///        no typo correction will be performed.
1325Parser::AnnotatedNameKind
1326Parser::TryAnnotateName(bool IsAddressOfOperand,
1327                        std::unique_ptr<CorrectionCandidateCallback> CCC) {
1328  assert(Tok.is(tok::identifier) || Tok.is(tok::annot_cxxscope));
1329
1330  const bool EnteringContext = false;
1331  const bool WasScopeAnnotation = Tok.is(tok::annot_cxxscope);
1332
1333  CXXScopeSpec SS;
1334  if (getLangOpts().CPlusPlus &&
1335      ParseOptionalCXXScopeSpecifier(SS, ParsedType(), EnteringContext))
1336    return ANK_Error;
1337
1338  if (Tok.isNot(tok::identifier) || SS.isInvalid()) {
1339    if (TryAnnotateTypeOrScopeTokenAfterScopeSpec(EnteringContext, false, SS,
1340                                                  !WasScopeAnnotation))
1341      return ANK_Error;
1342    return ANK_Unresolved;
1343  }
1344
1345  IdentifierInfo *Name = Tok.getIdentifierInfo();
1346  SourceLocation NameLoc = Tok.getLocation();
1347
1348  // FIXME: Move the tentative declaration logic into ClassifyName so we can
1349  // typo-correct to tentatively-declared identifiers.
1350  if (isTentativelyDeclared(Name)) {
1351    // Identifier has been tentatively declared, and thus cannot be resolved as
1352    // an expression. Fall back to annotating it as a type.
1353    if (TryAnnotateTypeOrScopeTokenAfterScopeSpec(EnteringContext, false, SS,
1354                                                  !WasScopeAnnotation))
1355      return ANK_Error;
1356    return Tok.is(tok::annot_typename) ? ANK_Success : ANK_TentativeDecl;
1357  }
1358
1359  Token Next = NextToken();
1360
1361  // Look up and classify the identifier. We don't perform any typo-correction
1362  // after a scope specifier, because in general we can't recover from typos
1363  // there (eg, after correcting 'A::tempalte B<X>::C' [sic], we would need to
1364  // jump back into scope specifier parsing).
1365  Sema::NameClassification Classification = Actions.ClassifyName(
1366      getCurScope(), SS, Name, NameLoc, Next, IsAddressOfOperand,
1367      SS.isEmpty() ? std::move(CCC) : nullptr);
1368
1369  switch (Classification.getKind()) {
1370  case Sema::NC_Error:
1371    return ANK_Error;
1372
1373  case Sema::NC_Keyword:
1374    // The identifier was typo-corrected to a keyword.
1375    Tok.setIdentifierInfo(Name);
1376    Tok.setKind(Name->getTokenID());
1377    PP.TypoCorrectToken(Tok);
1378    if (SS.isNotEmpty())
1379      AnnotateScopeToken(SS, !WasScopeAnnotation);
1380    // We've "annotated" this as a keyword.
1381    return ANK_Success;
1382
1383  case Sema::NC_Unknown:
1384    // It's not something we know about. Leave it unannotated.
1385    break;
1386
1387  case Sema::NC_Type:
1388    Tok.setKind(tok::annot_typename);
1389    setTypeAnnotation(Tok, Classification.getType());
1390    Tok.setAnnotationEndLoc(NameLoc);
1391    if (SS.isNotEmpty())
1392      Tok.setLocation(SS.getBeginLoc());
1393    PP.AnnotateCachedTokens(Tok);
1394    return ANK_Success;
1395
1396  case Sema::NC_Expression:
1397    Tok.setKind(tok::annot_primary_expr);
1398    setExprAnnotation(Tok, Classification.getExpression());
1399    Tok.setAnnotationEndLoc(NameLoc);
1400    if (SS.isNotEmpty())
1401      Tok.setLocation(SS.getBeginLoc());
1402    PP.AnnotateCachedTokens(Tok);
1403    return ANK_Success;
1404
1405  case Sema::NC_TypeTemplate:
1406    if (Next.isNot(tok::less)) {
1407      // This may be a type template being used as a template template argument.
1408      if (SS.isNotEmpty())
1409        AnnotateScopeToken(SS, !WasScopeAnnotation);
1410      return ANK_TemplateName;
1411    }
1412    // Fall through.
1413  case Sema::NC_VarTemplate:
1414  case Sema::NC_FunctionTemplate: {
1415    // We have a type, variable or function template followed by '<'.
1416    ConsumeToken();
1417    UnqualifiedId Id;
1418    Id.setIdentifier(Name, NameLoc);
1419    if (AnnotateTemplateIdToken(
1420            TemplateTy::make(Classification.getTemplateName()),
1421            Classification.getTemplateNameKind(), SS, SourceLocation(), Id))
1422      return ANK_Error;
1423    return ANK_Success;
1424  }
1425
1426  case Sema::NC_NestedNameSpecifier:
1427    llvm_unreachable("already parsed nested name specifier");
1428  }
1429
1430  // Unable to classify the name, but maybe we can annotate a scope specifier.
1431  if (SS.isNotEmpty())
1432    AnnotateScopeToken(SS, !WasScopeAnnotation);
1433  return ANK_Unresolved;
1434}
1435
1436bool Parser::TryKeywordIdentFallback(bool DisableKeyword) {
1437  assert(Tok.isNot(tok::identifier));
1438  Diag(Tok, diag::ext_keyword_as_ident)
1439    << PP.getSpelling(Tok)
1440    << DisableKeyword;
1441  if (DisableKeyword)
1442    Tok.getIdentifierInfo()->RevertTokenIDToIdentifier();
1443  Tok.setKind(tok::identifier);
1444  return true;
1445}
1446
1447/// TryAnnotateTypeOrScopeToken - If the current token position is on a
1448/// typename (possibly qualified in C++) or a C++ scope specifier not followed
1449/// by a typename, TryAnnotateTypeOrScopeToken will replace one or more tokens
1450/// with a single annotation token representing the typename or C++ scope
1451/// respectively.
1452/// This simplifies handling of C++ scope specifiers and allows efficient
1453/// backtracking without the need to re-parse and resolve nested-names and
1454/// typenames.
1455/// It will mainly be called when we expect to treat identifiers as typenames
1456/// (if they are typenames). For example, in C we do not expect identifiers
1457/// inside expressions to be treated as typenames so it will not be called
1458/// for expressions in C.
1459/// The benefit for C/ObjC is that a typename will be annotated and
1460/// Actions.getTypeName will not be needed to be called again (e.g. getTypeName
1461/// will not be called twice, once to check whether we have a declaration
1462/// specifier, and another one to get the actual type inside
1463/// ParseDeclarationSpecifiers).
1464///
1465/// This returns true if an error occurred.
1466///
1467/// Note that this routine emits an error if you call it with ::new or ::delete
1468/// as the current tokens, so only call it in contexts where these are invalid.
1469bool Parser::TryAnnotateTypeOrScopeToken(bool EnteringContext, bool NeedType) {
1470  assert((Tok.is(tok::identifier) || Tok.is(tok::coloncolon) ||
1471          Tok.is(tok::kw_typename) || Tok.is(tok::annot_cxxscope) ||
1472          Tok.is(tok::kw_decltype) || Tok.is(tok::annot_template_id) ||
1473          Tok.is(tok::kw___super)) &&
1474         "Cannot be a type or scope token!");
1475
1476  if (Tok.is(tok::kw_typename)) {
1477    // MSVC lets you do stuff like:
1478    //   typename typedef T_::D D;
1479    //
1480    // We will consume the typedef token here and put it back after we have
1481    // parsed the first identifier, transforming it into something more like:
1482    //   typename T_::D typedef D;
1483    if (getLangOpts().MSVCCompat && NextToken().is(tok::kw_typedef)) {
1484      Token TypedefToken;
1485      PP.Lex(TypedefToken);
1486      bool Result = TryAnnotateTypeOrScopeToken(EnteringContext, NeedType);
1487      PP.EnterToken(Tok);
1488      Tok = TypedefToken;
1489      if (!Result)
1490        Diag(Tok.getLocation(), diag::warn_expected_qualified_after_typename);
1491      return Result;
1492    }
1493
1494    // Parse a C++ typename-specifier, e.g., "typename T::type".
1495    //
1496    //   typename-specifier:
1497    //     'typename' '::' [opt] nested-name-specifier identifier
1498    //     'typename' '::' [opt] nested-name-specifier template [opt]
1499    //            simple-template-id
1500    SourceLocation TypenameLoc = ConsumeToken();
1501    CXXScopeSpec SS;
1502    if (ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/ParsedType(),
1503                                       /*EnteringContext=*/false,
1504                                       nullptr, /*IsTypename*/ true))
1505      return true;
1506    if (!SS.isSet()) {
1507      if (Tok.is(tok::identifier) || Tok.is(tok::annot_template_id) ||
1508          Tok.is(tok::annot_decltype)) {
1509        // Attempt to recover by skipping the invalid 'typename'
1510        if (Tok.is(tok::annot_decltype) ||
1511            (!TryAnnotateTypeOrScopeToken(EnteringContext, NeedType) &&
1512             Tok.isAnnotation())) {
1513          unsigned DiagID = diag::err_expected_qualified_after_typename;
1514          // MS compatibility: MSVC permits using known types with typename.
1515          // e.g. "typedef typename T* pointer_type"
1516          if (getLangOpts().MicrosoftExt)
1517            DiagID = diag::warn_expected_qualified_after_typename;
1518          Diag(Tok.getLocation(), DiagID);
1519          return false;
1520        }
1521      }
1522
1523      Diag(Tok.getLocation(), diag::err_expected_qualified_after_typename);
1524      return true;
1525    }
1526
1527    TypeResult Ty;
1528    if (Tok.is(tok::identifier)) {
1529      // FIXME: check whether the next token is '<', first!
1530      Ty = Actions.ActOnTypenameType(getCurScope(), TypenameLoc, SS,
1531                                     *Tok.getIdentifierInfo(),
1532                                     Tok.getLocation());
1533    } else if (Tok.is(tok::annot_template_id)) {
1534      TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok);
1535      if (TemplateId->Kind != TNK_Type_template &&
1536          TemplateId->Kind != TNK_Dependent_template_name) {
1537        Diag(Tok, diag::err_typename_refers_to_non_type_template)
1538          << Tok.getAnnotationRange();
1539        return true;
1540      }
1541
1542      ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
1543                                         TemplateId->NumArgs);
1544
1545      Ty = Actions.ActOnTypenameType(getCurScope(), TypenameLoc, SS,
1546                                     TemplateId->TemplateKWLoc,
1547                                     TemplateId->Template,
1548                                     TemplateId->TemplateNameLoc,
1549                                     TemplateId->LAngleLoc,
1550                                     TemplateArgsPtr,
1551                                     TemplateId->RAngleLoc);
1552    } else {
1553      Diag(Tok, diag::err_expected_type_name_after_typename)
1554        << SS.getRange();
1555      return true;
1556    }
1557
1558    SourceLocation EndLoc = Tok.getLastLoc();
1559    Tok.setKind(tok::annot_typename);
1560    setTypeAnnotation(Tok, Ty.isInvalid() ? ParsedType() : Ty.get());
1561    Tok.setAnnotationEndLoc(EndLoc);
1562    Tok.setLocation(TypenameLoc);
1563    PP.AnnotateCachedTokens(Tok);
1564    return false;
1565  }
1566
1567  // Remembers whether the token was originally a scope annotation.
1568  bool WasScopeAnnotation = Tok.is(tok::annot_cxxscope);
1569
1570  CXXScopeSpec SS;
1571  if (getLangOpts().CPlusPlus)
1572    if (ParseOptionalCXXScopeSpecifier(SS, ParsedType(), EnteringContext))
1573      return true;
1574
1575  return TryAnnotateTypeOrScopeTokenAfterScopeSpec(EnteringContext, NeedType,
1576                                                   SS, !WasScopeAnnotation);
1577}
1578
1579/// \brief Try to annotate a type or scope token, having already parsed an
1580/// optional scope specifier. \p IsNewScope should be \c true unless the scope
1581/// specifier was extracted from an existing tok::annot_cxxscope annotation.
1582bool Parser::TryAnnotateTypeOrScopeTokenAfterScopeSpec(bool EnteringContext,
1583                                                       bool NeedType,
1584                                                       CXXScopeSpec &SS,
1585                                                       bool IsNewScope) {
1586  if (Tok.is(tok::identifier)) {
1587    IdentifierInfo *CorrectedII = nullptr;
1588    // Determine whether the identifier is a type name.
1589    if (ParsedType Ty = Actions.getTypeName(*Tok.getIdentifierInfo(),
1590                                            Tok.getLocation(), getCurScope(),
1591                                            &SS, false,
1592                                            NextToken().is(tok::period),
1593                                            ParsedType(),
1594                                            /*IsCtorOrDtorName=*/false,
1595                                            /*NonTrivialTypeSourceInfo*/ true,
1596                                            NeedType ? &CorrectedII
1597                                                     : nullptr)) {
1598      // A FixIt was applied as a result of typo correction
1599      if (CorrectedII)
1600        Tok.setIdentifierInfo(CorrectedII);
1601      // This is a typename. Replace the current token in-place with an
1602      // annotation type token.
1603      Tok.setKind(tok::annot_typename);
1604      setTypeAnnotation(Tok, Ty);
1605      Tok.setAnnotationEndLoc(Tok.getLocation());
1606      if (SS.isNotEmpty()) // it was a C++ qualified type name.
1607        Tok.setLocation(SS.getBeginLoc());
1608
1609      // In case the tokens were cached, have Preprocessor replace
1610      // them with the annotation token.
1611      PP.AnnotateCachedTokens(Tok);
1612      return false;
1613    }
1614
1615    if (!getLangOpts().CPlusPlus) {
1616      // If we're in C, we can't have :: tokens at all (the lexer won't return
1617      // them).  If the identifier is not a type, then it can't be scope either,
1618      // just early exit.
1619      return false;
1620    }
1621
1622    // If this is a template-id, annotate with a template-id or type token.
1623    if (NextToken().is(tok::less)) {
1624      TemplateTy Template;
1625      UnqualifiedId TemplateName;
1626      TemplateName.setIdentifier(Tok.getIdentifierInfo(), Tok.getLocation());
1627      bool MemberOfUnknownSpecialization;
1628      if (TemplateNameKind TNK
1629          = Actions.isTemplateName(getCurScope(), SS,
1630                                   /*hasTemplateKeyword=*/false, TemplateName,
1631                                   /*ObjectType=*/ ParsedType(),
1632                                   EnteringContext,
1633                                   Template, MemberOfUnknownSpecialization)) {
1634        // Consume the identifier.
1635        ConsumeToken();
1636        if (AnnotateTemplateIdToken(Template, TNK, SS, SourceLocation(),
1637                                    TemplateName)) {
1638          // If an unrecoverable error occurred, we need to return true here,
1639          // because the token stream is in a damaged state.  We may not return
1640          // a valid identifier.
1641          return true;
1642        }
1643      }
1644    }
1645
1646    // The current token, which is either an identifier or a
1647    // template-id, is not part of the annotation. Fall through to
1648    // push that token back into the stream and complete the C++ scope
1649    // specifier annotation.
1650  }
1651
1652  if (Tok.is(tok::annot_template_id)) {
1653    TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok);
1654    if (TemplateId->Kind == TNK_Type_template) {
1655      // A template-id that refers to a type was parsed into a
1656      // template-id annotation in a context where we weren't allowed
1657      // to produce a type annotation token. Update the template-id
1658      // annotation token to a type annotation token now.
1659      AnnotateTemplateIdTokenAsType();
1660      return false;
1661    }
1662  }
1663
1664  if (SS.isEmpty())
1665    return false;
1666
1667  // A C++ scope specifier that isn't followed by a typename.
1668  AnnotateScopeToken(SS, IsNewScope);
1669  return false;
1670}
1671
1672/// TryAnnotateScopeToken - Like TryAnnotateTypeOrScopeToken but only
1673/// annotates C++ scope specifiers and template-ids.  This returns
1674/// true if there was an error that could not be recovered from.
1675///
1676/// Note that this routine emits an error if you call it with ::new or ::delete
1677/// as the current tokens, so only call it in contexts where these are invalid.
1678bool Parser::TryAnnotateCXXScopeToken(bool EnteringContext) {
1679  assert(getLangOpts().CPlusPlus &&
1680         "Call sites of this function should be guarded by checking for C++");
1681  assert((Tok.is(tok::identifier) || Tok.is(tok::coloncolon) ||
1682          (Tok.is(tok::annot_template_id) && NextToken().is(tok::coloncolon)) ||
1683          Tok.is(tok::kw_decltype) || Tok.is(tok::kw___super)) &&
1684         "Cannot be a type or scope token!");
1685
1686  CXXScopeSpec SS;
1687  if (ParseOptionalCXXScopeSpecifier(SS, ParsedType(), EnteringContext))
1688    return true;
1689  if (SS.isEmpty())
1690    return false;
1691
1692  AnnotateScopeToken(SS, true);
1693  return false;
1694}
1695
1696bool Parser::isTokenEqualOrEqualTypo() {
1697  tok::TokenKind Kind = Tok.getKind();
1698  switch (Kind) {
1699  default:
1700    return false;
1701  case tok::ampequal:            // &=
1702  case tok::starequal:           // *=
1703  case tok::plusequal:           // +=
1704  case tok::minusequal:          // -=
1705  case tok::exclaimequal:        // !=
1706  case tok::slashequal:          // /=
1707  case tok::percentequal:        // %=
1708  case tok::lessequal:           // <=
1709  case tok::lesslessequal:       // <<=
1710  case tok::greaterequal:        // >=
1711  case tok::greatergreaterequal: // >>=
1712  case tok::caretequal:          // ^=
1713  case tok::pipeequal:           // |=
1714  case tok::equalequal:          // ==
1715    Diag(Tok, diag::err_invalid_token_after_declarator_suggest_equal)
1716        << Kind
1717        << FixItHint::CreateReplacement(SourceRange(Tok.getLocation()), "=");
1718  case tok::equal:
1719    return true;
1720  }
1721}
1722
1723SourceLocation Parser::handleUnexpectedCodeCompletionToken() {
1724  assert(Tok.is(tok::code_completion));
1725  PrevTokLocation = Tok.getLocation();
1726
1727  for (Scope *S = getCurScope(); S; S = S->getParent()) {
1728    if (S->getFlags() & Scope::FnScope) {
1729      Actions.CodeCompleteOrdinaryName(getCurScope(),
1730                                       Sema::PCC_RecoveryInFunction);
1731      cutOffParsing();
1732      return PrevTokLocation;
1733    }
1734
1735    if (S->getFlags() & Scope::ClassScope) {
1736      Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Class);
1737      cutOffParsing();
1738      return PrevTokLocation;
1739    }
1740  }
1741
1742  Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Namespace);
1743  cutOffParsing();
1744  return PrevTokLocation;
1745}
1746
1747// Code-completion pass-through functions
1748
1749void Parser::CodeCompleteDirective(bool InConditional) {
1750  Actions.CodeCompletePreprocessorDirective(InConditional);
1751}
1752
1753void Parser::CodeCompleteInConditionalExclusion() {
1754  Actions.CodeCompleteInPreprocessorConditionalExclusion(getCurScope());
1755}
1756
1757void Parser::CodeCompleteMacroName(bool IsDefinition) {
1758  Actions.CodeCompletePreprocessorMacroName(IsDefinition);
1759}
1760
1761void Parser::CodeCompletePreprocessorExpression() {
1762  Actions.CodeCompletePreprocessorExpression();
1763}
1764
1765void Parser::CodeCompleteMacroArgument(IdentifierInfo *Macro,
1766                                       MacroInfo *MacroInfo,
1767                                       unsigned ArgumentIndex) {
1768  Actions.CodeCompletePreprocessorMacroArgument(getCurScope(), Macro, MacroInfo,
1769                                                ArgumentIndex);
1770}
1771
1772void Parser::CodeCompleteNaturalLanguage() {
1773  Actions.CodeCompleteNaturalLanguage();
1774}
1775
1776bool Parser::ParseMicrosoftIfExistsCondition(IfExistsCondition& Result) {
1777  assert((Tok.is(tok::kw___if_exists) || Tok.is(tok::kw___if_not_exists)) &&
1778         "Expected '__if_exists' or '__if_not_exists'");
1779  Result.IsIfExists = Tok.is(tok::kw___if_exists);
1780  Result.KeywordLoc = ConsumeToken();
1781
1782  BalancedDelimiterTracker T(*this, tok::l_paren);
1783  if (T.consumeOpen()) {
1784    Diag(Tok, diag::err_expected_lparen_after)
1785      << (Result.IsIfExists? "__if_exists" : "__if_not_exists");
1786    return true;
1787  }
1788
1789  // Parse nested-name-specifier.
1790  if (getLangOpts().CPlusPlus)
1791    ParseOptionalCXXScopeSpecifier(Result.SS, ParsedType(),
1792                                   /*EnteringContext=*/false);
1793
1794  // Check nested-name specifier.
1795  if (Result.SS.isInvalid()) {
1796    T.skipToEnd();
1797    return true;
1798  }
1799
1800  // Parse the unqualified-id.
1801  SourceLocation TemplateKWLoc; // FIXME: parsed, but unused.
1802  if (ParseUnqualifiedId(Result.SS, false, true, true, ParsedType(),
1803                         TemplateKWLoc, Result.Name)) {
1804    T.skipToEnd();
1805    return true;
1806  }
1807
1808  if (T.consumeClose())
1809    return true;
1810
1811  // Check if the symbol exists.
1812  switch (Actions.CheckMicrosoftIfExistsSymbol(getCurScope(), Result.KeywordLoc,
1813                                               Result.IsIfExists, Result.SS,
1814                                               Result.Name)) {
1815  case Sema::IER_Exists:
1816    Result.Behavior = Result.IsIfExists ? IEB_Parse : IEB_Skip;
1817    break;
1818
1819  case Sema::IER_DoesNotExist:
1820    Result.Behavior = !Result.IsIfExists ? IEB_Parse : IEB_Skip;
1821    break;
1822
1823  case Sema::IER_Dependent:
1824    Result.Behavior = IEB_Dependent;
1825    break;
1826
1827  case Sema::IER_Error:
1828    return true;
1829  }
1830
1831  return false;
1832}
1833
1834void Parser::ParseMicrosoftIfExistsExternalDeclaration() {
1835  IfExistsCondition Result;
1836  if (ParseMicrosoftIfExistsCondition(Result))
1837    return;
1838
1839  BalancedDelimiterTracker Braces(*this, tok::l_brace);
1840  if (Braces.consumeOpen()) {
1841    Diag(Tok, diag::err_expected) << tok::l_brace;
1842    return;
1843  }
1844
1845  switch (Result.Behavior) {
1846  case IEB_Parse:
1847    // Parse declarations below.
1848    break;
1849
1850  case IEB_Dependent:
1851    llvm_unreachable("Cannot have a dependent external declaration");
1852
1853  case IEB_Skip:
1854    Braces.skipToEnd();
1855    return;
1856  }
1857
1858  // Parse the declarations.
1859  // FIXME: Support module import within __if_exists?
1860  while (Tok.isNot(tok::r_brace) && !isEofOrEom()) {
1861    ParsedAttributesWithRange attrs(AttrFactory);
1862    MaybeParseCXX11Attributes(attrs);
1863    MaybeParseMicrosoftAttributes(attrs);
1864    DeclGroupPtrTy Result = ParseExternalDeclaration(attrs);
1865    if (Result && !getCurScope()->getParent())
1866      Actions.getASTConsumer().HandleTopLevelDecl(Result.get());
1867  }
1868  Braces.consumeClose();
1869}
1870
1871Parser::DeclGroupPtrTy Parser::ParseModuleImport(SourceLocation AtLoc) {
1872  assert(Tok.isObjCAtKeyword(tok::objc_import) &&
1873         "Improper start to module import");
1874  SourceLocation ImportLoc = ConsumeToken();
1875
1876  SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Path;
1877
1878  // Parse the module path.
1879  do {
1880    if (!Tok.is(tok::identifier)) {
1881      if (Tok.is(tok::code_completion)) {
1882        Actions.CodeCompleteModuleImport(ImportLoc, Path);
1883        cutOffParsing();
1884        return DeclGroupPtrTy();
1885      }
1886
1887      Diag(Tok, diag::err_module_expected_ident);
1888      SkipUntil(tok::semi);
1889      return DeclGroupPtrTy();
1890    }
1891
1892    // Record this part of the module path.
1893    Path.push_back(std::make_pair(Tok.getIdentifierInfo(), Tok.getLocation()));
1894    ConsumeToken();
1895
1896    if (Tok.is(tok::period)) {
1897      ConsumeToken();
1898      continue;
1899    }
1900
1901    break;
1902  } while (true);
1903
1904  if (PP.hadModuleLoaderFatalFailure()) {
1905    // With a fatal failure in the module loader, we abort parsing.
1906    cutOffParsing();
1907    return DeclGroupPtrTy();
1908  }
1909
1910  DeclResult Import = Actions.ActOnModuleImport(AtLoc, ImportLoc, Path);
1911  ExpectAndConsumeSemi(diag::err_module_expected_semi);
1912  if (Import.isInvalid())
1913    return DeclGroupPtrTy();
1914
1915  return Actions.ConvertDeclToDeclGroup(Import.get());
1916}
1917
1918bool BalancedDelimiterTracker::diagnoseOverflow() {
1919  P.Diag(P.Tok, diag::err_bracket_depth_exceeded)
1920    << P.getLangOpts().BracketDepth;
1921  P.Diag(P.Tok, diag::note_bracket_depth);
1922  P.cutOffParsing();
1923  return true;
1924}
1925
1926bool BalancedDelimiterTracker::expectAndConsume(unsigned DiagID,
1927                                                const char *Msg,
1928                                                tok::TokenKind SkipToTok) {
1929  LOpen = P.Tok.getLocation();
1930  if (P.ExpectAndConsume(Kind, DiagID, Msg)) {
1931    if (SkipToTok != tok::unknown)
1932      P.SkipUntil(SkipToTok, Parser::StopAtSemi);
1933    return true;
1934  }
1935
1936  if (getDepth() < MaxDepth)
1937    return false;
1938
1939  return diagnoseOverflow();
1940}
1941
1942bool BalancedDelimiterTracker::diagnoseMissingClose() {
1943  assert(!P.Tok.is(Close) && "Should have consumed closing delimiter");
1944
1945  P.Diag(P.Tok, diag::err_expected) << Close;
1946  P.Diag(LOpen, diag::note_matching) << Kind;
1947
1948  // If we're not already at some kind of closing bracket, skip to our closing
1949  // token.
1950  if (P.Tok.isNot(tok::r_paren) && P.Tok.isNot(tok::r_brace) &&
1951      P.Tok.isNot(tok::r_square) &&
1952      P.SkipUntil(Close, FinalToken,
1953                  Parser::StopAtSemi | Parser::StopBeforeMatch) &&
1954      P.Tok.is(Close))
1955    LClose = P.ConsumeAnyToken();
1956  return true;
1957}
1958
1959void BalancedDelimiterTracker::skipToEnd() {
1960  P.SkipUntil(Close, Parser::StopBeforeMatch);
1961  consumeClose();
1962}
1963