1 //===--- Parser.cpp - C Language Family Parser ----------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements the Parser interfaces.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "clang/Parse/Parser.h"
14 #include "clang/AST/ASTConsumer.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/DeclTemplate.h"
17 #include "clang/Basic/FileManager.h"
18 #include "clang/Parse/ParseDiagnostic.h"
19 #include "clang/Parse/RAIIObjectsForParser.h"
20 #include "clang/Sema/DeclSpec.h"
21 #include "clang/Sema/ParsedTemplate.h"
22 #include "clang/Sema/Scope.h"
23 #include "llvm/Support/Path.h"
24 using namespace clang;
25
26
27 namespace {
28 /// A comment handler that passes comments found by the preprocessor
29 /// to the parser action.
30 class ActionCommentHandler : public CommentHandler {
31 Sema &S;
32
33 public:
ActionCommentHandler(Sema & S)34 explicit ActionCommentHandler(Sema &S) : S(S) { }
35
HandleComment(Preprocessor & PP,SourceRange Comment)36 bool HandleComment(Preprocessor &PP, SourceRange Comment) override {
37 S.ActOnComment(Comment);
38 return false;
39 }
40 };
41 } // end anonymous namespace
42
getSEHExceptKeyword()43 IdentifierInfo *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
Parser(Preprocessor & pp,Sema & actions,bool skipFunctionBodies)51 Parser::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 CurParsedObjCImpl = nullptr;
62
63 // Add #pragma handlers. These are removed and destroyed in the
64 // destructor.
65 initializePragmaHandlers();
66
67 CommentSemaHandler.reset(new ActionCommentHandler(actions));
68 PP.addCommentHandler(CommentSemaHandler.get());
69
70 PP.setCodeCompletionHandler(*this);
71 }
72
Diag(SourceLocation Loc,unsigned DiagID)73 DiagnosticBuilder Parser::Diag(SourceLocation Loc, unsigned DiagID) {
74 return Diags.Report(Loc, DiagID);
75 }
76
Diag(const Token & Tok,unsigned DiagID)77 DiagnosticBuilder Parser::Diag(const Token &Tok, unsigned DiagID) {
78 return Diag(Tok.getLocation(), DiagID);
79 }
80
81 /// Emits a diagnostic suggesting parentheses surrounding a
82 /// given range.
83 ///
84 /// \param Loc The location where we'll emit the diagnostic.
85 /// \param DK The kind of diagnostic to emit.
86 /// \param ParenRange Source range enclosing code that should be parenthesized.
SuggestParentheses(SourceLocation Loc,unsigned DK,SourceRange ParenRange)87 void Parser::SuggestParentheses(SourceLocation Loc, unsigned DK,
88 SourceRange ParenRange) {
89 SourceLocation EndLoc = PP.getLocForEndOfToken(ParenRange.getEnd());
90 if (!ParenRange.getEnd().isFileID() || EndLoc.isInvalid()) {
91 // We can't display the parentheses, so just dig the
92 // warning/error and return.
93 Diag(Loc, DK);
94 return;
95 }
96
97 Diag(Loc, DK)
98 << FixItHint::CreateInsertion(ParenRange.getBegin(), "(")
99 << FixItHint::CreateInsertion(EndLoc, ")");
100 }
101
IsCommonTypo(tok::TokenKind ExpectedTok,const Token & Tok)102 static bool IsCommonTypo(tok::TokenKind ExpectedTok, const Token &Tok) {
103 switch (ExpectedTok) {
104 case tok::semi:
105 return Tok.is(tok::colon) || Tok.is(tok::comma); // : or , for ;
106 default: return false;
107 }
108 }
109
ExpectAndConsume(tok::TokenKind ExpectedTok,unsigned DiagID,StringRef Msg)110 bool Parser::ExpectAndConsume(tok::TokenKind ExpectedTok, unsigned DiagID,
111 StringRef Msg) {
112 if (Tok.is(ExpectedTok) || Tok.is(tok::code_completion)) {
113 ConsumeAnyToken();
114 return false;
115 }
116
117 // Detect common single-character typos and resume.
118 if (IsCommonTypo(ExpectedTok, Tok)) {
119 SourceLocation Loc = Tok.getLocation();
120 {
121 DiagnosticBuilder DB = Diag(Loc, DiagID);
122 DB << FixItHint::CreateReplacement(
123 SourceRange(Loc), tok::getPunctuatorSpelling(ExpectedTok));
124 if (DiagID == diag::err_expected)
125 DB << ExpectedTok;
126 else if (DiagID == diag::err_expected_after)
127 DB << Msg << ExpectedTok;
128 else
129 DB << Msg;
130 }
131
132 // Pretend there wasn't a problem.
133 ConsumeAnyToken();
134 return false;
135 }
136
137 SourceLocation EndLoc = PP.getLocForEndOfToken(PrevTokLocation);
138 const char *Spelling = nullptr;
139 if (EndLoc.isValid())
140 Spelling = tok::getPunctuatorSpelling(ExpectedTok);
141
142 DiagnosticBuilder DB =
143 Spelling
144 ? Diag(EndLoc, DiagID) << FixItHint::CreateInsertion(EndLoc, Spelling)
145 : Diag(Tok, DiagID);
146 if (DiagID == diag::err_expected)
147 DB << ExpectedTok;
148 else if (DiagID == diag::err_expected_after)
149 DB << Msg << ExpectedTok;
150 else
151 DB << Msg;
152
153 return true;
154 }
155
ExpectAndConsumeSemi(unsigned DiagID)156 bool Parser::ExpectAndConsumeSemi(unsigned DiagID) {
157 if (TryConsumeToken(tok::semi))
158 return false;
159
160 if (Tok.is(tok::code_completion)) {
161 handleUnexpectedCodeCompletionToken();
162 return false;
163 }
164
165 if ((Tok.is(tok::r_paren) || Tok.is(tok::r_square)) &&
166 NextToken().is(tok::semi)) {
167 Diag(Tok, diag::err_extraneous_token_before_semi)
168 << PP.getSpelling(Tok)
169 << FixItHint::CreateRemoval(Tok.getLocation());
170 ConsumeAnyToken(); // The ')' or ']'.
171 ConsumeToken(); // The ';'.
172 return false;
173 }
174
175 return ExpectAndConsume(tok::semi, DiagID);
176 }
177
ConsumeExtraSemi(ExtraSemiKind Kind,DeclSpec::TST TST)178 void Parser::ConsumeExtraSemi(ExtraSemiKind Kind, DeclSpec::TST TST) {
179 if (!Tok.is(tok::semi)) return;
180
181 bool HadMultipleSemis = false;
182 SourceLocation StartLoc = Tok.getLocation();
183 SourceLocation EndLoc = Tok.getLocation();
184 ConsumeToken();
185
186 while ((Tok.is(tok::semi) && !Tok.isAtStartOfLine())) {
187 HadMultipleSemis = true;
188 EndLoc = Tok.getLocation();
189 ConsumeToken();
190 }
191
192 // C++11 allows extra semicolons at namespace scope, but not in any of the
193 // other contexts.
194 if (Kind == OutsideFunction && getLangOpts().CPlusPlus) {
195 if (getLangOpts().CPlusPlus11)
196 Diag(StartLoc, diag::warn_cxx98_compat_top_level_semi)
197 << FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
198 else
199 Diag(StartLoc, diag::ext_extra_semi_cxx11)
200 << FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
201 return;
202 }
203
204 if (Kind != AfterMemberFunctionDefinition || HadMultipleSemis)
205 Diag(StartLoc, diag::ext_extra_semi)
206 << Kind << DeclSpec::getSpecifierName(TST,
207 Actions.getASTContext().getPrintingPolicy())
208 << FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
209 else
210 // A single semicolon is valid after a member function definition.
211 Diag(StartLoc, diag::warn_extra_semi_after_mem_fn_def)
212 << FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
213 }
214
expectIdentifier()215 bool Parser::expectIdentifier() {
216 if (Tok.is(tok::identifier))
217 return false;
218 if (const auto *II = Tok.getIdentifierInfo()) {
219 if (II->isCPlusPlusKeyword(getLangOpts())) {
220 Diag(Tok, diag::err_expected_token_instead_of_objcxx_keyword)
221 << tok::identifier << Tok.getIdentifierInfo();
222 // Objective-C++: Recover by treating this keyword as a valid identifier.
223 return false;
224 }
225 }
226 Diag(Tok, diag::err_expected) << tok::identifier;
227 return true;
228 }
229
checkCompoundToken(SourceLocation FirstTokLoc,tok::TokenKind FirstTokKind,CompoundToken Op)230 void Parser::checkCompoundToken(SourceLocation FirstTokLoc,
231 tok::TokenKind FirstTokKind, CompoundToken Op) {
232 if (FirstTokLoc.isInvalid())
233 return;
234 SourceLocation SecondTokLoc = Tok.getLocation();
235
236 // If either token is in a macro, we expect both tokens to come from the same
237 // macro expansion.
238 if ((FirstTokLoc.isMacroID() || SecondTokLoc.isMacroID()) &&
239 PP.getSourceManager().getFileID(FirstTokLoc) !=
240 PP.getSourceManager().getFileID(SecondTokLoc)) {
241 Diag(FirstTokLoc, diag::warn_compound_token_split_by_macro)
242 << (FirstTokKind == Tok.getKind()) << FirstTokKind << Tok.getKind()
243 << static_cast<int>(Op) << SourceRange(FirstTokLoc);
244 Diag(SecondTokLoc, diag::note_compound_token_split_second_token_here)
245 << (FirstTokKind == Tok.getKind()) << Tok.getKind()
246 << SourceRange(SecondTokLoc);
247 return;
248 }
249
250 // We expect the tokens to abut.
251 if (Tok.hasLeadingSpace() || Tok.isAtStartOfLine()) {
252 SourceLocation SpaceLoc = PP.getLocForEndOfToken(FirstTokLoc);
253 if (SpaceLoc.isInvalid())
254 SpaceLoc = FirstTokLoc;
255 Diag(SpaceLoc, diag::warn_compound_token_split_by_whitespace)
256 << (FirstTokKind == Tok.getKind()) << FirstTokKind << Tok.getKind()
257 << static_cast<int>(Op) << SourceRange(FirstTokLoc, SecondTokLoc);
258 return;
259 }
260 }
261
262 //===----------------------------------------------------------------------===//
263 // Error recovery.
264 //===----------------------------------------------------------------------===//
265
HasFlagsSet(Parser::SkipUntilFlags L,Parser::SkipUntilFlags R)266 static bool HasFlagsSet(Parser::SkipUntilFlags L, Parser::SkipUntilFlags R) {
267 return (static_cast<unsigned>(L) & static_cast<unsigned>(R)) != 0;
268 }
269
270 /// SkipUntil - Read tokens until we get to the specified token, then consume
271 /// it (unless no flag StopBeforeMatch). Because we cannot guarantee that the
272 /// token will ever occur, this skips to the next token, or to some likely
273 /// good stopping point. If StopAtSemi is true, skipping will stop at a ';'
274 /// character.
275 ///
276 /// If SkipUntil finds the specified token, it returns true, otherwise it
277 /// returns false.
SkipUntil(ArrayRef<tok::TokenKind> Toks,SkipUntilFlags Flags)278 bool Parser::SkipUntil(ArrayRef<tok::TokenKind> Toks, SkipUntilFlags Flags) {
279 // We always want this function to skip at least one token if the first token
280 // isn't T and if not at EOF.
281 bool isFirstTokenSkipped = true;
282 while (1) {
283 // If we found one of the tokens, stop and return true.
284 for (unsigned i = 0, NumToks = Toks.size(); i != NumToks; ++i) {
285 if (Tok.is(Toks[i])) {
286 if (HasFlagsSet(Flags, StopBeforeMatch)) {
287 // Noop, don't consume the token.
288 } else {
289 ConsumeAnyToken();
290 }
291 return true;
292 }
293 }
294
295 // Important special case: The caller has given up and just wants us to
296 // skip the rest of the file. Do this without recursing, since we can
297 // get here precisely because the caller detected too much recursion.
298 if (Toks.size() == 1 && Toks[0] == tok::eof &&
299 !HasFlagsSet(Flags, StopAtSemi) &&
300 !HasFlagsSet(Flags, StopAtCodeCompletion)) {
301 while (Tok.isNot(tok::eof))
302 ConsumeAnyToken();
303 return true;
304 }
305
306 switch (Tok.getKind()) {
307 case tok::eof:
308 // Ran out of tokens.
309 return false;
310
311 case tok::annot_pragma_openmp:
312 case tok::annot_pragma_openmp_end:
313 // Stop before an OpenMP pragma boundary.
314 if (OpenMPDirectiveParsing)
315 return false;
316 ConsumeAnnotationToken();
317 break;
318 case tok::annot_module_begin:
319 case tok::annot_module_end:
320 case tok::annot_module_include:
321 // Stop before we change submodules. They generally indicate a "good"
322 // place to pick up parsing again (except in the special case where
323 // we're trying to skip to EOF).
324 return false;
325
326 case tok::code_completion:
327 if (!HasFlagsSet(Flags, StopAtCodeCompletion))
328 handleUnexpectedCodeCompletionToken();
329 return false;
330
331 case tok::l_paren:
332 // Recursively skip properly-nested parens.
333 ConsumeParen();
334 if (HasFlagsSet(Flags, StopAtCodeCompletion))
335 SkipUntil(tok::r_paren, StopAtCodeCompletion);
336 else
337 SkipUntil(tok::r_paren);
338 break;
339 case tok::l_square:
340 // Recursively skip properly-nested square brackets.
341 ConsumeBracket();
342 if (HasFlagsSet(Flags, StopAtCodeCompletion))
343 SkipUntil(tok::r_square, StopAtCodeCompletion);
344 else
345 SkipUntil(tok::r_square);
346 break;
347 case tok::l_brace:
348 // Recursively skip properly-nested braces.
349 ConsumeBrace();
350 if (HasFlagsSet(Flags, StopAtCodeCompletion))
351 SkipUntil(tok::r_brace, StopAtCodeCompletion);
352 else
353 SkipUntil(tok::r_brace);
354 break;
355 case tok::question:
356 // Recursively skip ? ... : pairs; these function as brackets. But
357 // still stop at a semicolon if requested.
358 ConsumeToken();
359 SkipUntil(tok::colon,
360 SkipUntilFlags(unsigned(Flags) &
361 unsigned(StopAtCodeCompletion | StopAtSemi)));
362 break;
363
364 // Okay, we found a ']' or '}' or ')', which we think should be balanced.
365 // Since the user wasn't looking for this token (if they were, it would
366 // already be handled), this isn't balanced. If there is a LHS token at a
367 // higher level, we will assume that this matches the unbalanced token
368 // and return it. Otherwise, this is a spurious RHS token, which we skip.
369 case tok::r_paren:
370 if (ParenCount && !isFirstTokenSkipped)
371 return false; // Matches something.
372 ConsumeParen();
373 break;
374 case tok::r_square:
375 if (BracketCount && !isFirstTokenSkipped)
376 return false; // Matches something.
377 ConsumeBracket();
378 break;
379 case tok::r_brace:
380 if (BraceCount && !isFirstTokenSkipped)
381 return false; // Matches something.
382 ConsumeBrace();
383 break;
384
385 case tok::semi:
386 if (HasFlagsSet(Flags, StopAtSemi))
387 return false;
388 LLVM_FALLTHROUGH;
389 default:
390 // Skip this token.
391 ConsumeAnyToken();
392 break;
393 }
394 isFirstTokenSkipped = false;
395 }
396 }
397
398 //===----------------------------------------------------------------------===//
399 // Scope manipulation
400 //===----------------------------------------------------------------------===//
401
402 /// EnterScope - Start a new scope.
EnterScope(unsigned ScopeFlags)403 void Parser::EnterScope(unsigned ScopeFlags) {
404 if (NumCachedScopes) {
405 Scope *N = ScopeCache[--NumCachedScopes];
406 N->Init(getCurScope(), ScopeFlags);
407 Actions.CurScope = N;
408 } else {
409 Actions.CurScope = new Scope(getCurScope(), ScopeFlags, Diags);
410 }
411 }
412
413 /// ExitScope - Pop a scope off the scope stack.
ExitScope()414 void Parser::ExitScope() {
415 assert(getCurScope() && "Scope imbalance!");
416
417 // Inform the actions module that this scope is going away if there are any
418 // decls in it.
419 Actions.ActOnPopScope(Tok.getLocation(), getCurScope());
420
421 Scope *OldScope = getCurScope();
422 Actions.CurScope = OldScope->getParent();
423
424 if (NumCachedScopes == ScopeCacheSize)
425 delete OldScope;
426 else
427 ScopeCache[NumCachedScopes++] = OldScope;
428 }
429
430 /// Set the flags for the current scope to ScopeFlags. If ManageFlags is false,
431 /// this object does nothing.
ParseScopeFlags(Parser * Self,unsigned ScopeFlags,bool ManageFlags)432 Parser::ParseScopeFlags::ParseScopeFlags(Parser *Self, unsigned ScopeFlags,
433 bool ManageFlags)
434 : CurScope(ManageFlags ? Self->getCurScope() : nullptr) {
435 if (CurScope) {
436 OldFlags = CurScope->getFlags();
437 CurScope->setFlags(ScopeFlags);
438 }
439 }
440
441 /// Restore the flags for the current scope to what they were before this
442 /// object overrode them.
~ParseScopeFlags()443 Parser::ParseScopeFlags::~ParseScopeFlags() {
444 if (CurScope)
445 CurScope->setFlags(OldFlags);
446 }
447
448
449 //===----------------------------------------------------------------------===//
450 // C99 6.9: External Definitions.
451 //===----------------------------------------------------------------------===//
452
~Parser()453 Parser::~Parser() {
454 // If we still have scopes active, delete the scope tree.
455 delete getCurScope();
456 Actions.CurScope = nullptr;
457
458 // Free the scope cache.
459 for (unsigned i = 0, e = NumCachedScopes; i != e; ++i)
460 delete ScopeCache[i];
461
462 resetPragmaHandlers();
463
464 PP.removeCommentHandler(CommentSemaHandler.get());
465
466 PP.clearCodeCompletionHandler();
467
468 DestroyTemplateIds();
469 }
470
471 /// Initialize - Warm up the parser.
472 ///
Initialize()473 void Parser::Initialize() {
474 // Create the translation unit scope. Install it as the current scope.
475 assert(getCurScope() == nullptr && "A scope is already active?");
476 EnterScope(Scope::DeclScope);
477 Actions.ActOnTranslationUnitScope(getCurScope());
478
479 // Initialization for Objective-C context sensitive keywords recognition.
480 // Referenced in Parser::ParseObjCTypeQualifierList.
481 if (getLangOpts().ObjC) {
482 ObjCTypeQuals[objc_in] = &PP.getIdentifierTable().get("in");
483 ObjCTypeQuals[objc_out] = &PP.getIdentifierTable().get("out");
484 ObjCTypeQuals[objc_inout] = &PP.getIdentifierTable().get("inout");
485 ObjCTypeQuals[objc_oneway] = &PP.getIdentifierTable().get("oneway");
486 ObjCTypeQuals[objc_bycopy] = &PP.getIdentifierTable().get("bycopy");
487 ObjCTypeQuals[objc_byref] = &PP.getIdentifierTable().get("byref");
488 ObjCTypeQuals[objc_nonnull] = &PP.getIdentifierTable().get("nonnull");
489 ObjCTypeQuals[objc_nullable] = &PP.getIdentifierTable().get("nullable");
490 ObjCTypeQuals[objc_null_unspecified]
491 = &PP.getIdentifierTable().get("null_unspecified");
492 }
493
494 Ident_instancetype = nullptr;
495 Ident_final = nullptr;
496 Ident_sealed = nullptr;
497 Ident_override = nullptr;
498 Ident_GNU_final = nullptr;
499 Ident_import = nullptr;
500 Ident_module = nullptr;
501
502 Ident_super = &PP.getIdentifierTable().get("super");
503
504 Ident_vector = nullptr;
505 Ident_bool = nullptr;
506 Ident_pixel = nullptr;
507 if (getLangOpts().AltiVec || getLangOpts().ZVector) {
508 Ident_vector = &PP.getIdentifierTable().get("vector");
509 Ident_bool = &PP.getIdentifierTable().get("bool");
510 }
511 if (getLangOpts().AltiVec)
512 Ident_pixel = &PP.getIdentifierTable().get("pixel");
513
514 Ident_introduced = nullptr;
515 Ident_deprecated = nullptr;
516 Ident_obsoleted = nullptr;
517 Ident_unavailable = nullptr;
518 Ident_strict = nullptr;
519 Ident_replacement = nullptr;
520
521 Ident_language = Ident_defined_in = Ident_generated_declaration = nullptr;
522
523 Ident__except = nullptr;
524
525 Ident__exception_code = Ident__exception_info = nullptr;
526 Ident__abnormal_termination = Ident___exception_code = nullptr;
527 Ident___exception_info = Ident___abnormal_termination = nullptr;
528 Ident_GetExceptionCode = Ident_GetExceptionInfo = nullptr;
529 Ident_AbnormalTermination = nullptr;
530
531 if(getLangOpts().Borland) {
532 Ident__exception_info = PP.getIdentifierInfo("_exception_info");
533 Ident___exception_info = PP.getIdentifierInfo("__exception_info");
534 Ident_GetExceptionInfo = PP.getIdentifierInfo("GetExceptionInformation");
535 Ident__exception_code = PP.getIdentifierInfo("_exception_code");
536 Ident___exception_code = PP.getIdentifierInfo("__exception_code");
537 Ident_GetExceptionCode = PP.getIdentifierInfo("GetExceptionCode");
538 Ident__abnormal_termination = PP.getIdentifierInfo("_abnormal_termination");
539 Ident___abnormal_termination = PP.getIdentifierInfo("__abnormal_termination");
540 Ident_AbnormalTermination = PP.getIdentifierInfo("AbnormalTermination");
541
542 PP.SetPoisonReason(Ident__exception_code,diag::err_seh___except_block);
543 PP.SetPoisonReason(Ident___exception_code,diag::err_seh___except_block);
544 PP.SetPoisonReason(Ident_GetExceptionCode,diag::err_seh___except_block);
545 PP.SetPoisonReason(Ident__exception_info,diag::err_seh___except_filter);
546 PP.SetPoisonReason(Ident___exception_info,diag::err_seh___except_filter);
547 PP.SetPoisonReason(Ident_GetExceptionInfo,diag::err_seh___except_filter);
548 PP.SetPoisonReason(Ident__abnormal_termination,diag::err_seh___finally_block);
549 PP.SetPoisonReason(Ident___abnormal_termination,diag::err_seh___finally_block);
550 PP.SetPoisonReason(Ident_AbnormalTermination,diag::err_seh___finally_block);
551 }
552
553 if (getLangOpts().CPlusPlusModules) {
554 Ident_import = PP.getIdentifierInfo("import");
555 Ident_module = PP.getIdentifierInfo("module");
556 }
557
558 Actions.Initialize();
559
560 // Prime the lexer look-ahead.
561 ConsumeToken();
562 }
563
DestroyTemplateIds()564 void Parser::DestroyTemplateIds() {
565 for (TemplateIdAnnotation *Id : TemplateIds)
566 Id->Destroy();
567 TemplateIds.clear();
568 }
569
570 /// Parse the first top-level declaration in a translation unit.
571 ///
572 /// translation-unit:
573 /// [C] external-declaration
574 /// [C] translation-unit external-declaration
575 /// [C++] top-level-declaration-seq[opt]
576 /// [C++20] global-module-fragment[opt] module-declaration
577 /// top-level-declaration-seq[opt] private-module-fragment[opt]
578 ///
579 /// Note that in C, it is an error if there is no first declaration.
ParseFirstTopLevelDecl(DeclGroupPtrTy & Result)580 bool Parser::ParseFirstTopLevelDecl(DeclGroupPtrTy &Result) {
581 Actions.ActOnStartOfTranslationUnit();
582
583 // C11 6.9p1 says translation units must have at least one top-level
584 // declaration. C++ doesn't have this restriction. We also don't want to
585 // complain if we have a precompiled header, although technically if the PCH
586 // is empty we should still emit the (pedantic) diagnostic.
587 // If the main file is a header, we're only pretending it's a TU; don't warn.
588 bool NoTopLevelDecls = ParseTopLevelDecl(Result, true);
589 if (NoTopLevelDecls && !Actions.getASTContext().getExternalSource() &&
590 !getLangOpts().CPlusPlus && !getLangOpts().IsHeaderFile)
591 Diag(diag::ext_empty_translation_unit);
592
593 return NoTopLevelDecls;
594 }
595
596 /// ParseTopLevelDecl - Parse one top-level declaration, return whatever the
597 /// action tells us to. This returns true if the EOF was encountered.
598 ///
599 /// top-level-declaration:
600 /// declaration
601 /// [C++20] module-import-declaration
ParseTopLevelDecl(DeclGroupPtrTy & Result,bool IsFirstDecl)602 bool Parser::ParseTopLevelDecl(DeclGroupPtrTy &Result, bool IsFirstDecl) {
603 DestroyTemplateIdAnnotationsRAIIObj CleanupRAII(*this);
604
605 // Skip over the EOF token, flagging end of previous input for incremental
606 // processing
607 if (PP.isIncrementalProcessingEnabled() && Tok.is(tok::eof))
608 ConsumeToken();
609
610 Result = nullptr;
611 switch (Tok.getKind()) {
612 case tok::annot_pragma_unused:
613 HandlePragmaUnused();
614 return false;
615
616 case tok::kw_export:
617 switch (NextToken().getKind()) {
618 case tok::kw_module:
619 goto module_decl;
620
621 // Note: no need to handle kw_import here. We only form kw_import under
622 // the Modules TS, and in that case 'export import' is parsed as an
623 // export-declaration containing an import-declaration.
624
625 // Recognize context-sensitive C++20 'export module' and 'export import'
626 // declarations.
627 case tok::identifier: {
628 IdentifierInfo *II = NextToken().getIdentifierInfo();
629 if ((II == Ident_module || II == Ident_import) &&
630 GetLookAheadToken(2).isNot(tok::coloncolon)) {
631 if (II == Ident_module)
632 goto module_decl;
633 else
634 goto import_decl;
635 }
636 break;
637 }
638
639 default:
640 break;
641 }
642 break;
643
644 case tok::kw_module:
645 module_decl:
646 Result = ParseModuleDecl(IsFirstDecl);
647 return false;
648
649 // tok::kw_import is handled by ParseExternalDeclaration. (Under the Modules
650 // TS, an import can occur within an export block.)
651 import_decl: {
652 Decl *ImportDecl = ParseModuleImport(SourceLocation());
653 Result = Actions.ConvertDeclToDeclGroup(ImportDecl);
654 return false;
655 }
656
657 case tok::annot_module_include:
658 Actions.ActOnModuleInclude(Tok.getLocation(),
659 reinterpret_cast<Module *>(
660 Tok.getAnnotationValue()));
661 ConsumeAnnotationToken();
662 return false;
663
664 case tok::annot_module_begin:
665 Actions.ActOnModuleBegin(Tok.getLocation(), reinterpret_cast<Module *>(
666 Tok.getAnnotationValue()));
667 ConsumeAnnotationToken();
668 return false;
669
670 case tok::annot_module_end:
671 Actions.ActOnModuleEnd(Tok.getLocation(), reinterpret_cast<Module *>(
672 Tok.getAnnotationValue()));
673 ConsumeAnnotationToken();
674 return false;
675
676 case tok::eof:
677 // Check whether -fmax-tokens= was reached.
678 if (PP.getMaxTokens() != 0 && PP.getTokenCount() > PP.getMaxTokens()) {
679 PP.Diag(Tok.getLocation(), diag::warn_max_tokens_total)
680 << PP.getTokenCount() << PP.getMaxTokens();
681 SourceLocation OverrideLoc = PP.getMaxTokensOverrideLoc();
682 if (OverrideLoc.isValid()) {
683 PP.Diag(OverrideLoc, diag::note_max_tokens_total_override);
684 }
685 }
686
687 // Late template parsing can begin.
688 Actions.SetLateTemplateParser(LateTemplateParserCallback, nullptr, this);
689 if (!PP.isIncrementalProcessingEnabled())
690 Actions.ActOnEndOfTranslationUnit();
691 //else don't tell Sema that we ended parsing: more input might come.
692 return true;
693
694 case tok::identifier:
695 // C++2a [basic.link]p3:
696 // A token sequence beginning with 'export[opt] module' or
697 // 'export[opt] import' and not immediately followed by '::'
698 // is never interpreted as the declaration of a top-level-declaration.
699 if ((Tok.getIdentifierInfo() == Ident_module ||
700 Tok.getIdentifierInfo() == Ident_import) &&
701 NextToken().isNot(tok::coloncolon)) {
702 if (Tok.getIdentifierInfo() == Ident_module)
703 goto module_decl;
704 else
705 goto import_decl;
706 }
707 break;
708
709 default:
710 break;
711 }
712
713 ParsedAttributesWithRange attrs(AttrFactory);
714 MaybeParseCXX11Attributes(attrs);
715
716 Result = ParseExternalDeclaration(attrs);
717 return false;
718 }
719
720 /// ParseExternalDeclaration:
721 ///
722 /// external-declaration: [C99 6.9], declaration: [C++ dcl.dcl]
723 /// function-definition
724 /// declaration
725 /// [GNU] asm-definition
726 /// [GNU] __extension__ external-declaration
727 /// [OBJC] objc-class-definition
728 /// [OBJC] objc-class-declaration
729 /// [OBJC] objc-alias-declaration
730 /// [OBJC] objc-protocol-definition
731 /// [OBJC] objc-method-definition
732 /// [OBJC] @end
733 /// [C++] linkage-specification
734 /// [GNU] asm-definition:
735 /// simple-asm-expr ';'
736 /// [C++11] empty-declaration
737 /// [C++11] attribute-declaration
738 ///
739 /// [C++11] empty-declaration:
740 /// ';'
741 ///
742 /// [C++0x/GNU] 'extern' 'template' declaration
743 ///
744 /// [Modules-TS] module-import-declaration
745 ///
746 Parser::DeclGroupPtrTy
ParseExternalDeclaration(ParsedAttributesWithRange & attrs,ParsingDeclSpec * DS)747 Parser::ParseExternalDeclaration(ParsedAttributesWithRange &attrs,
748 ParsingDeclSpec *DS) {
749 DestroyTemplateIdAnnotationsRAIIObj CleanupRAII(*this);
750 ParenBraceBracketBalancer BalancerRAIIObj(*this);
751
752 if (PP.isCodeCompletionReached()) {
753 cutOffParsing();
754 return nullptr;
755 }
756
757 Decl *SingleDecl = nullptr;
758 switch (Tok.getKind()) {
759 case tok::annot_pragma_vis:
760 HandlePragmaVisibility();
761 return nullptr;
762 case tok::annot_pragma_pack:
763 HandlePragmaPack();
764 return nullptr;
765 case tok::annot_pragma_msstruct:
766 HandlePragmaMSStruct();
767 return nullptr;
768 case tok::annot_pragma_align:
769 HandlePragmaAlign();
770 return nullptr;
771 case tok::annot_pragma_weak:
772 HandlePragmaWeak();
773 return nullptr;
774 case tok::annot_pragma_weakalias:
775 HandlePragmaWeakAlias();
776 return nullptr;
777 case tok::annot_pragma_redefine_extname:
778 HandlePragmaRedefineExtname();
779 return nullptr;
780 case tok::annot_pragma_fp_contract:
781 HandlePragmaFPContract();
782 return nullptr;
783 case tok::annot_pragma_fenv_access:
784 HandlePragmaFEnvAccess();
785 return nullptr;
786 case tok::annot_pragma_fenv_round:
787 HandlePragmaFEnvRound();
788 return nullptr;
789 case tok::annot_pragma_float_control:
790 HandlePragmaFloatControl();
791 return nullptr;
792 case tok::annot_pragma_fp:
793 HandlePragmaFP();
794 break;
795 case tok::annot_pragma_opencl_extension:
796 HandlePragmaOpenCLExtension();
797 return nullptr;
798 case tok::annot_pragma_openmp: {
799 AccessSpecifier AS = AS_none;
800 return ParseOpenMPDeclarativeDirectiveWithExtDecl(AS, attrs);
801 }
802 case tok::annot_pragma_ms_pointers_to_members:
803 HandlePragmaMSPointersToMembers();
804 return nullptr;
805 case tok::annot_pragma_ms_vtordisp:
806 HandlePragmaMSVtorDisp();
807 return nullptr;
808 case tok::annot_pragma_ms_pragma:
809 HandlePragmaMSPragma();
810 return nullptr;
811 case tok::annot_pragma_dump:
812 HandlePragmaDump();
813 return nullptr;
814 case tok::annot_pragma_attribute:
815 HandlePragmaAttribute();
816 return nullptr;
817 case tok::semi:
818 // Either a C++11 empty-declaration or attribute-declaration.
819 SingleDecl =
820 Actions.ActOnEmptyDeclaration(getCurScope(), attrs, Tok.getLocation());
821 ConsumeExtraSemi(OutsideFunction);
822 break;
823 case tok::r_brace:
824 Diag(Tok, diag::err_extraneous_closing_brace);
825 ConsumeBrace();
826 return nullptr;
827 case tok::eof:
828 Diag(Tok, diag::err_expected_external_declaration);
829 return nullptr;
830 case tok::kw___extension__: {
831 // __extension__ silences extension warnings in the subexpression.
832 ExtensionRAIIObject O(Diags); // Use RAII to do this.
833 ConsumeToken();
834 return ParseExternalDeclaration(attrs);
835 }
836 case tok::kw_asm: {
837 ProhibitAttributes(attrs);
838
839 SourceLocation StartLoc = Tok.getLocation();
840 SourceLocation EndLoc;
841
842 ExprResult Result(ParseSimpleAsm(/*ForAsmLabel*/ false, &EndLoc));
843
844 // Check if GNU-style InlineAsm is disabled.
845 // Empty asm string is allowed because it will not introduce
846 // any assembly code.
847 if (!(getLangOpts().GNUAsm || Result.isInvalid())) {
848 const auto *SL = cast<StringLiteral>(Result.get());
849 if (!SL->getString().trim().empty())
850 Diag(StartLoc, diag::err_gnu_inline_asm_disabled);
851 }
852
853 ExpectAndConsume(tok::semi, diag::err_expected_after,
854 "top-level asm block");
855
856 if (Result.isInvalid())
857 return nullptr;
858 SingleDecl = Actions.ActOnFileScopeAsmDecl(Result.get(), StartLoc, EndLoc);
859 break;
860 }
861 case tok::at:
862 return ParseObjCAtDirectives(attrs);
863 case tok::minus:
864 case tok::plus:
865 if (!getLangOpts().ObjC) {
866 Diag(Tok, diag::err_expected_external_declaration);
867 ConsumeToken();
868 return nullptr;
869 }
870 SingleDecl = ParseObjCMethodDefinition();
871 break;
872 case tok::code_completion:
873 if (CurParsedObjCImpl) {
874 // Code-complete Objective-C methods even without leading '-'/'+' prefix.
875 Actions.CodeCompleteObjCMethodDecl(getCurScope(),
876 /*IsInstanceMethod=*/None,
877 /*ReturnType=*/nullptr);
878 }
879 Actions.CodeCompleteOrdinaryName(
880 getCurScope(),
881 CurParsedObjCImpl ? Sema::PCC_ObjCImplementation : Sema::PCC_Namespace);
882 cutOffParsing();
883 return nullptr;
884 case tok::kw_import:
885 SingleDecl = ParseModuleImport(SourceLocation());
886 break;
887 case tok::kw_export:
888 if (getLangOpts().CPlusPlusModules || getLangOpts().ModulesTS) {
889 SingleDecl = ParseExportDeclaration();
890 break;
891 }
892 // This must be 'export template'. Parse it so we can diagnose our lack
893 // of support.
894 LLVM_FALLTHROUGH;
895 case tok::kw_using:
896 case tok::kw_namespace:
897 case tok::kw_typedef:
898 case tok::kw_template:
899 case tok::kw_static_assert:
900 case tok::kw__Static_assert:
901 // A function definition cannot start with any of these keywords.
902 {
903 SourceLocation DeclEnd;
904 return ParseDeclaration(DeclaratorContext::File, DeclEnd, attrs);
905 }
906
907 case tok::kw_static:
908 // Parse (then ignore) 'static' prior to a template instantiation. This is
909 // a GCC extension that we intentionally do not support.
910 if (getLangOpts().CPlusPlus && NextToken().is(tok::kw_template)) {
911 Diag(ConsumeToken(), diag::warn_static_inline_explicit_inst_ignored)
912 << 0;
913 SourceLocation DeclEnd;
914 return ParseDeclaration(DeclaratorContext::File, DeclEnd, attrs);
915 }
916 goto dont_know;
917
918 case tok::kw_inline:
919 if (getLangOpts().CPlusPlus) {
920 tok::TokenKind NextKind = NextToken().getKind();
921
922 // Inline namespaces. Allowed as an extension even in C++03.
923 if (NextKind == tok::kw_namespace) {
924 SourceLocation DeclEnd;
925 return ParseDeclaration(DeclaratorContext::File, DeclEnd, attrs);
926 }
927
928 // Parse (then ignore) 'inline' prior to a template instantiation. This is
929 // a GCC extension that we intentionally do not support.
930 if (NextKind == tok::kw_template) {
931 Diag(ConsumeToken(), diag::warn_static_inline_explicit_inst_ignored)
932 << 1;
933 SourceLocation DeclEnd;
934 return ParseDeclaration(DeclaratorContext::File, DeclEnd, attrs);
935 }
936 }
937 goto dont_know;
938
939 case tok::kw_extern:
940 if (getLangOpts().CPlusPlus && NextToken().is(tok::kw_template)) {
941 // Extern templates
942 SourceLocation ExternLoc = ConsumeToken();
943 SourceLocation TemplateLoc = ConsumeToken();
944 Diag(ExternLoc, getLangOpts().CPlusPlus11 ?
945 diag::warn_cxx98_compat_extern_template :
946 diag::ext_extern_template) << SourceRange(ExternLoc, TemplateLoc);
947 SourceLocation DeclEnd;
948 return Actions.ConvertDeclToDeclGroup(ParseExplicitInstantiation(
949 DeclaratorContext::File, ExternLoc, TemplateLoc, DeclEnd, attrs));
950 }
951 goto dont_know;
952
953 case tok::kw___if_exists:
954 case tok::kw___if_not_exists:
955 ParseMicrosoftIfExistsExternalDeclaration();
956 return nullptr;
957
958 case tok::kw_module:
959 Diag(Tok, diag::err_unexpected_module_decl);
960 SkipUntil(tok::semi);
961 return nullptr;
962
963 default:
964 dont_know:
965 if (Tok.isEditorPlaceholder()) {
966 ConsumeToken();
967 return nullptr;
968 }
969 // We can't tell whether this is a function-definition or declaration yet.
970 return ParseDeclarationOrFunctionDefinition(attrs, DS);
971 }
972
973 // This routine returns a DeclGroup, if the thing we parsed only contains a
974 // single decl, convert it now.
975 return Actions.ConvertDeclToDeclGroup(SingleDecl);
976 }
977
978 /// Determine whether the current token, if it occurs after a
979 /// declarator, continues a declaration or declaration list.
isDeclarationAfterDeclarator()980 bool Parser::isDeclarationAfterDeclarator() {
981 // Check for '= delete' or '= default'
982 if (getLangOpts().CPlusPlus && Tok.is(tok::equal)) {
983 const Token &KW = NextToken();
984 if (KW.is(tok::kw_default) || KW.is(tok::kw_delete))
985 return false;
986 }
987
988 return Tok.is(tok::equal) || // int X()= -> not a function def
989 Tok.is(tok::comma) || // int X(), -> not a function def
990 Tok.is(tok::semi) || // int X(); -> not a function def
991 Tok.is(tok::kw_asm) || // int X() __asm__ -> not a function def
992 Tok.is(tok::kw___attribute) || // int X() __attr__ -> not a function def
993 (getLangOpts().CPlusPlus &&
994 Tok.is(tok::l_paren)); // int X(0) -> not a function def [C++]
995 }
996
997 /// Determine whether the current token, if it occurs after a
998 /// declarator, indicates the start of a function definition.
isStartOfFunctionDefinition(const ParsingDeclarator & Declarator)999 bool Parser::isStartOfFunctionDefinition(const ParsingDeclarator &Declarator) {
1000 assert(Declarator.isFunctionDeclarator() && "Isn't a function declarator");
1001 if (Tok.is(tok::l_brace)) // int X() {}
1002 return true;
1003
1004 // Handle K&R C argument lists: int X(f) int f; {}
1005 if (!getLangOpts().CPlusPlus &&
1006 Declarator.getFunctionTypeInfo().isKNRPrototype())
1007 return isDeclarationSpecifier();
1008
1009 if (getLangOpts().CPlusPlus && Tok.is(tok::equal)) {
1010 const Token &KW = NextToken();
1011 return KW.is(tok::kw_default) || KW.is(tok::kw_delete);
1012 }
1013
1014 return Tok.is(tok::colon) || // X() : Base() {} (used for ctors)
1015 Tok.is(tok::kw_try); // X() try { ... }
1016 }
1017
1018 /// Parse either a function-definition or a declaration. We can't tell which
1019 /// we have until we read up to the compound-statement in function-definition.
1020 /// TemplateParams, if non-NULL, provides the template parameters when we're
1021 /// parsing a C++ template-declaration.
1022 ///
1023 /// function-definition: [C99 6.9.1]
1024 /// decl-specs declarator declaration-list[opt] compound-statement
1025 /// [C90] function-definition: [C99 6.7.1] - implicit int result
1026 /// [C90] decl-specs[opt] declarator declaration-list[opt] compound-statement
1027 ///
1028 /// declaration: [C99 6.7]
1029 /// declaration-specifiers init-declarator-list[opt] ';'
1030 /// [!C99] init-declarator-list ';' [TODO: warn in c99 mode]
1031 /// [OMP] threadprivate-directive
1032 /// [OMP] allocate-directive [TODO]
1033 ///
1034 Parser::DeclGroupPtrTy
ParseDeclOrFunctionDefInternal(ParsedAttributesWithRange & attrs,ParsingDeclSpec & DS,AccessSpecifier AS)1035 Parser::ParseDeclOrFunctionDefInternal(ParsedAttributesWithRange &attrs,
1036 ParsingDeclSpec &DS,
1037 AccessSpecifier AS) {
1038 MaybeParseMicrosoftAttributes(DS.getAttributes());
1039 // Parse the common declaration-specifiers piece.
1040 ParseDeclarationSpecifiers(DS, ParsedTemplateInfo(), AS,
1041 DeclSpecContext::DSC_top_level);
1042
1043 // If we had a free-standing type definition with a missing semicolon, we
1044 // may get this far before the problem becomes obvious.
1045 if (DS.hasTagDefinition() && DiagnoseMissingSemiAfterTagDefinition(
1046 DS, AS, DeclSpecContext::DSC_top_level))
1047 return nullptr;
1048
1049 // C99 6.7.2.3p6: Handle "struct-or-union identifier;", "enum { X };"
1050 // declaration-specifiers init-declarator-list[opt] ';'
1051 if (Tok.is(tok::semi)) {
1052 auto LengthOfTSTToken = [](DeclSpec::TST TKind) {
1053 assert(DeclSpec::isDeclRep(TKind));
1054 switch(TKind) {
1055 case DeclSpec::TST_class:
1056 return 5;
1057 case DeclSpec::TST_struct:
1058 return 6;
1059 case DeclSpec::TST_union:
1060 return 5;
1061 case DeclSpec::TST_enum:
1062 return 4;
1063 case DeclSpec::TST_interface:
1064 return 9;
1065 default:
1066 llvm_unreachable("we only expect to get the length of the class/struct/union/enum");
1067 }
1068
1069 };
1070 // Suggest correct location to fix '[[attrib]] struct' to 'struct [[attrib]]'
1071 SourceLocation CorrectLocationForAttributes =
1072 DeclSpec::isDeclRep(DS.getTypeSpecType())
1073 ? DS.getTypeSpecTypeLoc().getLocWithOffset(
1074 LengthOfTSTToken(DS.getTypeSpecType()))
1075 : SourceLocation();
1076 ProhibitAttributes(attrs, CorrectLocationForAttributes);
1077 ConsumeToken();
1078 RecordDecl *AnonRecord = nullptr;
1079 Decl *TheDecl = Actions.ParsedFreeStandingDeclSpec(getCurScope(), AS_none,
1080 DS, AnonRecord);
1081 DS.complete(TheDecl);
1082 if (getLangOpts().OpenCL)
1083 Actions.setCurrentOpenCLExtensionForDecl(TheDecl);
1084 if (AnonRecord) {
1085 Decl* decls[] = {AnonRecord, TheDecl};
1086 return Actions.BuildDeclaratorGroup(decls);
1087 }
1088 return Actions.ConvertDeclToDeclGroup(TheDecl);
1089 }
1090
1091 DS.takeAttributesFrom(attrs);
1092
1093 // ObjC2 allows prefix attributes on class interfaces and protocols.
1094 // FIXME: This still needs better diagnostics. We should only accept
1095 // attributes here, no types, etc.
1096 if (getLangOpts().ObjC && Tok.is(tok::at)) {
1097 SourceLocation AtLoc = ConsumeToken(); // the "@"
1098 if (!Tok.isObjCAtKeyword(tok::objc_interface) &&
1099 !Tok.isObjCAtKeyword(tok::objc_protocol) &&
1100 !Tok.isObjCAtKeyword(tok::objc_implementation)) {
1101 Diag(Tok, diag::err_objc_unexpected_attr);
1102 SkipUntil(tok::semi);
1103 return nullptr;
1104 }
1105
1106 DS.abort();
1107
1108 const char *PrevSpec = nullptr;
1109 unsigned DiagID;
1110 if (DS.SetTypeSpecType(DeclSpec::TST_unspecified, AtLoc, PrevSpec, DiagID,
1111 Actions.getASTContext().getPrintingPolicy()))
1112 Diag(AtLoc, DiagID) << PrevSpec;
1113
1114 if (Tok.isObjCAtKeyword(tok::objc_protocol))
1115 return ParseObjCAtProtocolDeclaration(AtLoc, DS.getAttributes());
1116
1117 if (Tok.isObjCAtKeyword(tok::objc_implementation))
1118 return ParseObjCAtImplementationDeclaration(AtLoc, DS.getAttributes());
1119
1120 return Actions.ConvertDeclToDeclGroup(
1121 ParseObjCAtInterfaceDeclaration(AtLoc, DS.getAttributes()));
1122 }
1123
1124 // If the declspec consisted only of 'extern' and we have a string
1125 // literal following it, this must be a C++ linkage specifier like
1126 // 'extern "C"'.
1127 if (getLangOpts().CPlusPlus && isTokenStringLiteral() &&
1128 DS.getStorageClassSpec() == DeclSpec::SCS_extern &&
1129 DS.getParsedSpecifiers() == DeclSpec::PQ_StorageClassSpecifier) {
1130 Decl *TheDecl = ParseLinkage(DS, DeclaratorContext::File);
1131 return Actions.ConvertDeclToDeclGroup(TheDecl);
1132 }
1133
1134 return ParseDeclGroup(DS, DeclaratorContext::File);
1135 }
1136
1137 Parser::DeclGroupPtrTy
ParseDeclarationOrFunctionDefinition(ParsedAttributesWithRange & attrs,ParsingDeclSpec * DS,AccessSpecifier AS)1138 Parser::ParseDeclarationOrFunctionDefinition(ParsedAttributesWithRange &attrs,
1139 ParsingDeclSpec *DS,
1140 AccessSpecifier AS) {
1141 if (DS) {
1142 return ParseDeclOrFunctionDefInternal(attrs, *DS, AS);
1143 } else {
1144 ParsingDeclSpec PDS(*this);
1145 // Must temporarily exit the objective-c container scope for
1146 // parsing c constructs and re-enter objc container scope
1147 // afterwards.
1148 ObjCDeclContextSwitch ObjCDC(*this);
1149
1150 return ParseDeclOrFunctionDefInternal(attrs, PDS, AS);
1151 }
1152 }
1153
1154 /// ParseFunctionDefinition - We parsed and verified that the specified
1155 /// Declarator is well formed. If this is a K&R-style function, read the
1156 /// parameters declaration-list, then start the compound-statement.
1157 ///
1158 /// function-definition: [C99 6.9.1]
1159 /// decl-specs declarator declaration-list[opt] compound-statement
1160 /// [C90] function-definition: [C99 6.7.1] - implicit int result
1161 /// [C90] decl-specs[opt] declarator declaration-list[opt] compound-statement
1162 /// [C++] function-definition: [C++ 8.4]
1163 /// decl-specifier-seq[opt] declarator ctor-initializer[opt]
1164 /// function-body
1165 /// [C++] function-definition: [C++ 8.4]
1166 /// decl-specifier-seq[opt] declarator function-try-block
1167 ///
ParseFunctionDefinition(ParsingDeclarator & D,const ParsedTemplateInfo & TemplateInfo,LateParsedAttrList * LateParsedAttrs)1168 Decl *Parser::ParseFunctionDefinition(ParsingDeclarator &D,
1169 const ParsedTemplateInfo &TemplateInfo,
1170 LateParsedAttrList *LateParsedAttrs) {
1171 // Poison SEH identifiers so they are flagged as illegal in function bodies.
1172 PoisonSEHIdentifiersRAIIObject PoisonSEHIdentifiers(*this, true);
1173 const DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
1174 TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
1175
1176 // If this is C90 and the declspecs were completely missing, fudge in an
1177 // implicit int. We do this here because this is the only place where
1178 // declaration-specifiers are completely optional in the grammar.
1179 if (getLangOpts().ImplicitInt && D.getDeclSpec().isEmpty()) {
1180 const char *PrevSpec;
1181 unsigned DiagID;
1182 const PrintingPolicy &Policy = Actions.getASTContext().getPrintingPolicy();
1183 D.getMutableDeclSpec().SetTypeSpecType(DeclSpec::TST_int,
1184 D.getIdentifierLoc(),
1185 PrevSpec, DiagID,
1186 Policy);
1187 D.SetRangeBegin(D.getDeclSpec().getSourceRange().getBegin());
1188 }
1189
1190 // If this declaration was formed with a K&R-style identifier list for the
1191 // arguments, parse declarations for all of the args next.
1192 // int foo(a,b) int a; float b; {}
1193 if (FTI.isKNRPrototype())
1194 ParseKNRParamDeclarations(D);
1195
1196 // We should have either an opening brace or, in a C++ constructor,
1197 // we may have a colon.
1198 if (Tok.isNot(tok::l_brace) &&
1199 (!getLangOpts().CPlusPlus ||
1200 (Tok.isNot(tok::colon) && Tok.isNot(tok::kw_try) &&
1201 Tok.isNot(tok::equal)))) {
1202 Diag(Tok, diag::err_expected_fn_body);
1203
1204 // Skip over garbage, until we get to '{'. Don't eat the '{'.
1205 SkipUntil(tok::l_brace, StopAtSemi | StopBeforeMatch);
1206
1207 // If we didn't find the '{', bail out.
1208 if (Tok.isNot(tok::l_brace))
1209 return nullptr;
1210 }
1211
1212 // Check to make sure that any normal attributes are allowed to be on
1213 // a definition. Late parsed attributes are checked at the end.
1214 if (Tok.isNot(tok::equal)) {
1215 for (const ParsedAttr &AL : D.getAttributes())
1216 if (AL.isKnownToGCC() && !AL.isCXX11Attribute())
1217 Diag(AL.getLoc(), diag::warn_attribute_on_function_definition) << AL;
1218 }
1219
1220 // In delayed template parsing mode, for function template we consume the
1221 // tokens and store them for late parsing at the end of the translation unit.
1222 if (getLangOpts().DelayedTemplateParsing && Tok.isNot(tok::equal) &&
1223 TemplateInfo.Kind == ParsedTemplateInfo::Template &&
1224 Actions.canDelayFunctionBody(D)) {
1225 MultiTemplateParamsArg TemplateParameterLists(*TemplateInfo.TemplateParams);
1226
1227 ParseScope BodyScope(this, Scope::FnScope | Scope::DeclScope |
1228 Scope::CompoundStmtScope);
1229 Scope *ParentScope = getCurScope()->getParent();
1230
1231 D.setFunctionDefinitionKind(FunctionDefinitionKind::Definition);
1232 Decl *DP = Actions.HandleDeclarator(ParentScope, D,
1233 TemplateParameterLists);
1234 D.complete(DP);
1235 D.getMutableDeclSpec().abort();
1236
1237 if (SkipFunctionBodies && (!DP || Actions.canSkipFunctionBody(DP)) &&
1238 trySkippingFunctionBody()) {
1239 BodyScope.Exit();
1240 return Actions.ActOnSkippedFunctionBody(DP);
1241 }
1242
1243 CachedTokens Toks;
1244 LexTemplateFunctionForLateParsing(Toks);
1245
1246 if (DP) {
1247 FunctionDecl *FnD = DP->getAsFunction();
1248 Actions.CheckForFunctionRedefinition(FnD);
1249 Actions.MarkAsLateParsedTemplate(FnD, DP, Toks);
1250 }
1251 return DP;
1252 }
1253 else if (CurParsedObjCImpl &&
1254 !TemplateInfo.TemplateParams &&
1255 (Tok.is(tok::l_brace) || Tok.is(tok::kw_try) ||
1256 Tok.is(tok::colon)) &&
1257 Actions.CurContext->isTranslationUnit()) {
1258 ParseScope BodyScope(this, Scope::FnScope | Scope::DeclScope |
1259 Scope::CompoundStmtScope);
1260 Scope *ParentScope = getCurScope()->getParent();
1261
1262 D.setFunctionDefinitionKind(FunctionDefinitionKind::Definition);
1263 Decl *FuncDecl = Actions.HandleDeclarator(ParentScope, D,
1264 MultiTemplateParamsArg());
1265 D.complete(FuncDecl);
1266 D.getMutableDeclSpec().abort();
1267 if (FuncDecl) {
1268 // Consume the tokens and store them for later parsing.
1269 StashAwayMethodOrFunctionBodyTokens(FuncDecl);
1270 CurParsedObjCImpl->HasCFunction = true;
1271 return FuncDecl;
1272 }
1273 // FIXME: Should we really fall through here?
1274 }
1275
1276 // Enter a scope for the function body.
1277 ParseScope BodyScope(this, Scope::FnScope | Scope::DeclScope |
1278 Scope::CompoundStmtScope);
1279
1280 // Tell the actions module that we have entered a function definition with the
1281 // specified Declarator for the function.
1282 Sema::SkipBodyInfo SkipBody;
1283 Decl *Res = Actions.ActOnStartOfFunctionDef(getCurScope(), D,
1284 TemplateInfo.TemplateParams
1285 ? *TemplateInfo.TemplateParams
1286 : MultiTemplateParamsArg(),
1287 &SkipBody);
1288
1289 if (SkipBody.ShouldSkip) {
1290 SkipFunctionBody();
1291 return Res;
1292 }
1293
1294 // Break out of the ParsingDeclarator context before we parse the body.
1295 D.complete(Res);
1296
1297 // Break out of the ParsingDeclSpec context, too. This const_cast is
1298 // safe because we're always the sole owner.
1299 D.getMutableDeclSpec().abort();
1300
1301 // With abbreviated function templates - we need to explicitly add depth to
1302 // account for the implicit template parameter list induced by the template.
1303 if (auto *Template = dyn_cast_or_null<FunctionTemplateDecl>(Res))
1304 if (Template->isAbbreviated() &&
1305 Template->getTemplateParameters()->getParam(0)->isImplicit())
1306 // First template parameter is implicit - meaning no explicit template
1307 // parameter list was specified.
1308 CurTemplateDepthTracker.addDepth(1);
1309
1310 if (TryConsumeToken(tok::equal)) {
1311 assert(getLangOpts().CPlusPlus && "Only C++ function definitions have '='");
1312
1313 bool Delete = false;
1314 SourceLocation KWLoc;
1315 if (TryConsumeToken(tok::kw_delete, KWLoc)) {
1316 Diag(KWLoc, getLangOpts().CPlusPlus11
1317 ? diag::warn_cxx98_compat_defaulted_deleted_function
1318 : diag::ext_defaulted_deleted_function)
1319 << 1 /* deleted */;
1320 Actions.SetDeclDeleted(Res, KWLoc);
1321 Delete = true;
1322 } else if (TryConsumeToken(tok::kw_default, KWLoc)) {
1323 Diag(KWLoc, getLangOpts().CPlusPlus11
1324 ? diag::warn_cxx98_compat_defaulted_deleted_function
1325 : diag::ext_defaulted_deleted_function)
1326 << 0 /* defaulted */;
1327 Actions.SetDeclDefaulted(Res, KWLoc);
1328 } else {
1329 llvm_unreachable("function definition after = not 'delete' or 'default'");
1330 }
1331
1332 if (Tok.is(tok::comma)) {
1333 Diag(KWLoc, diag::err_default_delete_in_multiple_declaration)
1334 << Delete;
1335 SkipUntil(tok::semi);
1336 } else if (ExpectAndConsume(tok::semi, diag::err_expected_after,
1337 Delete ? "delete" : "default")) {
1338 SkipUntil(tok::semi);
1339 }
1340
1341 Stmt *GeneratedBody = Res ? Res->getBody() : nullptr;
1342 Actions.ActOnFinishFunctionBody(Res, GeneratedBody, false);
1343 return Res;
1344 }
1345
1346 if (SkipFunctionBodies && (!Res || Actions.canSkipFunctionBody(Res)) &&
1347 trySkippingFunctionBody()) {
1348 BodyScope.Exit();
1349 Actions.ActOnSkippedFunctionBody(Res);
1350 return Actions.ActOnFinishFunctionBody(Res, nullptr, false);
1351 }
1352
1353 if (Tok.is(tok::kw_try))
1354 return ParseFunctionTryBlock(Res, BodyScope);
1355
1356 // If we have a colon, then we're probably parsing a C++
1357 // ctor-initializer.
1358 if (Tok.is(tok::colon)) {
1359 ParseConstructorInitializer(Res);
1360
1361 // Recover from error.
1362 if (!Tok.is(tok::l_brace)) {
1363 BodyScope.Exit();
1364 Actions.ActOnFinishFunctionBody(Res, nullptr);
1365 return Res;
1366 }
1367 } else
1368 Actions.ActOnDefaultCtorInitializers(Res);
1369
1370 // Late attributes are parsed in the same scope as the function body.
1371 if (LateParsedAttrs)
1372 ParseLexedAttributeList(*LateParsedAttrs, Res, false, true);
1373
1374 return ParseFunctionStatementBody(Res, BodyScope);
1375 }
1376
SkipFunctionBody()1377 void Parser::SkipFunctionBody() {
1378 if (Tok.is(tok::equal)) {
1379 SkipUntil(tok::semi);
1380 return;
1381 }
1382
1383 bool IsFunctionTryBlock = Tok.is(tok::kw_try);
1384 if (IsFunctionTryBlock)
1385 ConsumeToken();
1386
1387 CachedTokens Skipped;
1388 if (ConsumeAndStoreFunctionPrologue(Skipped))
1389 SkipMalformedDecl();
1390 else {
1391 SkipUntil(tok::r_brace);
1392 while (IsFunctionTryBlock && Tok.is(tok::kw_catch)) {
1393 SkipUntil(tok::l_brace);
1394 SkipUntil(tok::r_brace);
1395 }
1396 }
1397 }
1398
1399 /// ParseKNRParamDeclarations - Parse 'declaration-list[opt]' which provides
1400 /// types for a function with a K&R-style identifier list for arguments.
ParseKNRParamDeclarations(Declarator & D)1401 void Parser::ParseKNRParamDeclarations(Declarator &D) {
1402 // We know that the top-level of this declarator is a function.
1403 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
1404
1405 // Enter function-declaration scope, limiting any declarators to the
1406 // function prototype scope, including parameter declarators.
1407 ParseScope PrototypeScope(this, Scope::FunctionPrototypeScope |
1408 Scope::FunctionDeclarationScope | Scope::DeclScope);
1409
1410 // Read all the argument declarations.
1411 while (isDeclarationSpecifier()) {
1412 SourceLocation DSStart = Tok.getLocation();
1413
1414 // Parse the common declaration-specifiers piece.
1415 DeclSpec DS(AttrFactory);
1416 ParseDeclarationSpecifiers(DS);
1417
1418 // C99 6.9.1p6: 'each declaration in the declaration list shall have at
1419 // least one declarator'.
1420 // NOTE: GCC just makes this an ext-warn. It's not clear what it does with
1421 // the declarations though. It's trivial to ignore them, really hard to do
1422 // anything else with them.
1423 if (TryConsumeToken(tok::semi)) {
1424 Diag(DSStart, diag::err_declaration_does_not_declare_param);
1425 continue;
1426 }
1427
1428 // C99 6.9.1p6: Declarations shall contain no storage-class specifiers other
1429 // than register.
1430 if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified &&
1431 DS.getStorageClassSpec() != DeclSpec::SCS_register) {
1432 Diag(DS.getStorageClassSpecLoc(),
1433 diag::err_invalid_storage_class_in_func_decl);
1434 DS.ClearStorageClassSpecs();
1435 }
1436 if (DS.getThreadStorageClassSpec() != DeclSpec::TSCS_unspecified) {
1437 Diag(DS.getThreadStorageClassSpecLoc(),
1438 diag::err_invalid_storage_class_in_func_decl);
1439 DS.ClearStorageClassSpecs();
1440 }
1441
1442 // Parse the first declarator attached to this declspec.
1443 Declarator ParmDeclarator(DS, DeclaratorContext::KNRTypeList);
1444 ParseDeclarator(ParmDeclarator);
1445
1446 // Handle the full declarator list.
1447 while (1) {
1448 // If attributes are present, parse them.
1449 MaybeParseGNUAttributes(ParmDeclarator);
1450
1451 // Ask the actions module to compute the type for this declarator.
1452 Decl *Param =
1453 Actions.ActOnParamDeclarator(getCurScope(), ParmDeclarator);
1454
1455 if (Param &&
1456 // A missing identifier has already been diagnosed.
1457 ParmDeclarator.getIdentifier()) {
1458
1459 // Scan the argument list looking for the correct param to apply this
1460 // type.
1461 for (unsigned i = 0; ; ++i) {
1462 // C99 6.9.1p6: those declarators shall declare only identifiers from
1463 // the identifier list.
1464 if (i == FTI.NumParams) {
1465 Diag(ParmDeclarator.getIdentifierLoc(), diag::err_no_matching_param)
1466 << ParmDeclarator.getIdentifier();
1467 break;
1468 }
1469
1470 if (FTI.Params[i].Ident == ParmDeclarator.getIdentifier()) {
1471 // Reject redefinitions of parameters.
1472 if (FTI.Params[i].Param) {
1473 Diag(ParmDeclarator.getIdentifierLoc(),
1474 diag::err_param_redefinition)
1475 << ParmDeclarator.getIdentifier();
1476 } else {
1477 FTI.Params[i].Param = Param;
1478 }
1479 break;
1480 }
1481 }
1482 }
1483
1484 // If we don't have a comma, it is either the end of the list (a ';') or
1485 // an error, bail out.
1486 if (Tok.isNot(tok::comma))
1487 break;
1488
1489 ParmDeclarator.clear();
1490
1491 // Consume the comma.
1492 ParmDeclarator.setCommaLoc(ConsumeToken());
1493
1494 // Parse the next declarator.
1495 ParseDeclarator(ParmDeclarator);
1496 }
1497
1498 // Consume ';' and continue parsing.
1499 if (!ExpectAndConsumeSemi(diag::err_expected_semi_declaration))
1500 continue;
1501
1502 // Otherwise recover by skipping to next semi or mandatory function body.
1503 if (SkipUntil(tok::l_brace, StopAtSemi | StopBeforeMatch))
1504 break;
1505 TryConsumeToken(tok::semi);
1506 }
1507
1508 // The actions module must verify that all arguments were declared.
1509 Actions.ActOnFinishKNRParamDeclarations(getCurScope(), D, Tok.getLocation());
1510 }
1511
1512
1513 /// ParseAsmStringLiteral - This is just a normal string-literal, but is not
1514 /// allowed to be a wide string, and is not subject to character translation.
1515 /// Unlike GCC, we also diagnose an empty string literal when parsing for an
1516 /// asm label as opposed to an asm statement, because such a construct does not
1517 /// behave well.
1518 ///
1519 /// [GNU] asm-string-literal:
1520 /// string-literal
1521 ///
ParseAsmStringLiteral(bool ForAsmLabel)1522 ExprResult Parser::ParseAsmStringLiteral(bool ForAsmLabel) {
1523 if (!isTokenStringLiteral()) {
1524 Diag(Tok, diag::err_expected_string_literal)
1525 << /*Source='in...'*/0 << "'asm'";
1526 return ExprError();
1527 }
1528
1529 ExprResult AsmString(ParseStringLiteralExpression());
1530 if (!AsmString.isInvalid()) {
1531 const auto *SL = cast<StringLiteral>(AsmString.get());
1532 if (!SL->isAscii()) {
1533 Diag(Tok, diag::err_asm_operand_wide_string_literal)
1534 << SL->isWide()
1535 << SL->getSourceRange();
1536 return ExprError();
1537 }
1538 if (ForAsmLabel && SL->getString().empty()) {
1539 Diag(Tok, diag::err_asm_operand_wide_string_literal)
1540 << 2 /* an empty */ << SL->getSourceRange();
1541 return ExprError();
1542 }
1543 }
1544 return AsmString;
1545 }
1546
1547 /// ParseSimpleAsm
1548 ///
1549 /// [GNU] simple-asm-expr:
1550 /// 'asm' '(' asm-string-literal ')'
1551 ///
ParseSimpleAsm(bool ForAsmLabel,SourceLocation * EndLoc)1552 ExprResult Parser::ParseSimpleAsm(bool ForAsmLabel, SourceLocation *EndLoc) {
1553 assert(Tok.is(tok::kw_asm) && "Not an asm!");
1554 SourceLocation Loc = ConsumeToken();
1555
1556 if (isGNUAsmQualifier(Tok)) {
1557 // Remove from the end of 'asm' to the end of the asm qualifier.
1558 SourceRange RemovalRange(PP.getLocForEndOfToken(Loc),
1559 PP.getLocForEndOfToken(Tok.getLocation()));
1560 Diag(Tok, diag::err_global_asm_qualifier_ignored)
1561 << GNUAsmQualifiers::getQualifierName(getGNUAsmQualifier(Tok))
1562 << FixItHint::CreateRemoval(RemovalRange);
1563 ConsumeToken();
1564 }
1565
1566 BalancedDelimiterTracker T(*this, tok::l_paren);
1567 if (T.consumeOpen()) {
1568 Diag(Tok, diag::err_expected_lparen_after) << "asm";
1569 return ExprError();
1570 }
1571
1572 ExprResult Result(ParseAsmStringLiteral(ForAsmLabel));
1573
1574 if (!Result.isInvalid()) {
1575 // Close the paren and get the location of the end bracket
1576 T.consumeClose();
1577 if (EndLoc)
1578 *EndLoc = T.getCloseLocation();
1579 } else if (SkipUntil(tok::r_paren, StopAtSemi | StopBeforeMatch)) {
1580 if (EndLoc)
1581 *EndLoc = Tok.getLocation();
1582 ConsumeParen();
1583 }
1584
1585 return Result;
1586 }
1587
1588 /// Get the TemplateIdAnnotation from the token and put it in the
1589 /// cleanup pool so that it gets destroyed when parsing the current top level
1590 /// declaration is finished.
takeTemplateIdAnnotation(const Token & tok)1591 TemplateIdAnnotation *Parser::takeTemplateIdAnnotation(const Token &tok) {
1592 assert(tok.is(tok::annot_template_id) && "Expected template-id token");
1593 TemplateIdAnnotation *
1594 Id = static_cast<TemplateIdAnnotation *>(tok.getAnnotationValue());
1595 return Id;
1596 }
1597
AnnotateScopeToken(CXXScopeSpec & SS,bool IsNewAnnotation)1598 void Parser::AnnotateScopeToken(CXXScopeSpec &SS, bool IsNewAnnotation) {
1599 // Push the current token back into the token stream (or revert it if it is
1600 // cached) and use an annotation scope token for current token.
1601 if (PP.isBacktrackEnabled())
1602 PP.RevertCachedTokens(1);
1603 else
1604 PP.EnterToken(Tok, /*IsReinject=*/true);
1605 Tok.setKind(tok::annot_cxxscope);
1606 Tok.setAnnotationValue(Actions.SaveNestedNameSpecifierAnnotation(SS));
1607 Tok.setAnnotationRange(SS.getRange());
1608
1609 // In case the tokens were cached, have Preprocessor replace them
1610 // with the annotation token. We don't need to do this if we've
1611 // just reverted back to a prior state.
1612 if (IsNewAnnotation)
1613 PP.AnnotateCachedTokens(Tok);
1614 }
1615
1616 /// Attempt to classify the name at the current token position. This may
1617 /// form a type, scope or primary expression annotation, or replace the token
1618 /// with a typo-corrected keyword. This is only appropriate when the current
1619 /// name must refer to an entity which has already been declared.
1620 ///
1621 /// \param CCC Indicates how to perform typo-correction for this name. If NULL,
1622 /// no typo correction will be performed.
1623 Parser::AnnotatedNameKind
TryAnnotateName(CorrectionCandidateCallback * CCC)1624 Parser::TryAnnotateName(CorrectionCandidateCallback *CCC) {
1625 assert(Tok.is(tok::identifier) || Tok.is(tok::annot_cxxscope));
1626
1627 const bool EnteringContext = false;
1628 const bool WasScopeAnnotation = Tok.is(tok::annot_cxxscope);
1629
1630 CXXScopeSpec SS;
1631 if (getLangOpts().CPlusPlus &&
1632 ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
1633 /*ObjectHadErrors=*/false,
1634 EnteringContext))
1635 return ANK_Error;
1636
1637 if (Tok.isNot(tok::identifier) || SS.isInvalid()) {
1638 if (TryAnnotateTypeOrScopeTokenAfterScopeSpec(SS, !WasScopeAnnotation))
1639 return ANK_Error;
1640 return ANK_Unresolved;
1641 }
1642
1643 IdentifierInfo *Name = Tok.getIdentifierInfo();
1644 SourceLocation NameLoc = Tok.getLocation();
1645
1646 // FIXME: Move the tentative declaration logic into ClassifyName so we can
1647 // typo-correct to tentatively-declared identifiers.
1648 if (isTentativelyDeclared(Name)) {
1649 // Identifier has been tentatively declared, and thus cannot be resolved as
1650 // an expression. Fall back to annotating it as a type.
1651 if (TryAnnotateTypeOrScopeTokenAfterScopeSpec(SS, !WasScopeAnnotation))
1652 return ANK_Error;
1653 return Tok.is(tok::annot_typename) ? ANK_Success : ANK_TentativeDecl;
1654 }
1655
1656 Token Next = NextToken();
1657
1658 // Look up and classify the identifier. We don't perform any typo-correction
1659 // after a scope specifier, because in general we can't recover from typos
1660 // there (eg, after correcting 'A::template B<X>::C' [sic], we would need to
1661 // jump back into scope specifier parsing).
1662 Sema::NameClassification Classification = Actions.ClassifyName(
1663 getCurScope(), SS, Name, NameLoc, Next, SS.isEmpty() ? CCC : nullptr);
1664
1665 // If name lookup found nothing and we guessed that this was a template name,
1666 // double-check before committing to that interpretation. C++20 requires that
1667 // we interpret this as a template-id if it can be, but if it can't be, then
1668 // this is an error recovery case.
1669 if (Classification.getKind() == Sema::NC_UndeclaredTemplate &&
1670 isTemplateArgumentList(1) == TPResult::False) {
1671 // It's not a template-id; re-classify without the '<' as a hint.
1672 Token FakeNext = Next;
1673 FakeNext.setKind(tok::unknown);
1674 Classification =
1675 Actions.ClassifyName(getCurScope(), SS, Name, NameLoc, FakeNext,
1676 SS.isEmpty() ? CCC : nullptr);
1677 }
1678
1679 switch (Classification.getKind()) {
1680 case Sema::NC_Error:
1681 return ANK_Error;
1682
1683 case Sema::NC_Keyword:
1684 // The identifier was typo-corrected to a keyword.
1685 Tok.setIdentifierInfo(Name);
1686 Tok.setKind(Name->getTokenID());
1687 PP.TypoCorrectToken(Tok);
1688 if (SS.isNotEmpty())
1689 AnnotateScopeToken(SS, !WasScopeAnnotation);
1690 // We've "annotated" this as a keyword.
1691 return ANK_Success;
1692
1693 case Sema::NC_Unknown:
1694 // It's not something we know about. Leave it unannotated.
1695 break;
1696
1697 case Sema::NC_Type: {
1698 SourceLocation BeginLoc = NameLoc;
1699 if (SS.isNotEmpty())
1700 BeginLoc = SS.getBeginLoc();
1701
1702 /// An Objective-C object type followed by '<' is a specialization of
1703 /// a parameterized class type or a protocol-qualified type.
1704 ParsedType Ty = Classification.getType();
1705 if (getLangOpts().ObjC && NextToken().is(tok::less) &&
1706 (Ty.get()->isObjCObjectType() ||
1707 Ty.get()->isObjCObjectPointerType())) {
1708 // Consume the name.
1709 SourceLocation IdentifierLoc = ConsumeToken();
1710 SourceLocation NewEndLoc;
1711 TypeResult NewType
1712 = parseObjCTypeArgsAndProtocolQualifiers(IdentifierLoc, Ty,
1713 /*consumeLastToken=*/false,
1714 NewEndLoc);
1715 if (NewType.isUsable())
1716 Ty = NewType.get();
1717 else if (Tok.is(tok::eof)) // Nothing to do here, bail out...
1718 return ANK_Error;
1719 }
1720
1721 Tok.setKind(tok::annot_typename);
1722 setTypeAnnotation(Tok, Ty);
1723 Tok.setAnnotationEndLoc(Tok.getLocation());
1724 Tok.setLocation(BeginLoc);
1725 PP.AnnotateCachedTokens(Tok);
1726 return ANK_Success;
1727 }
1728
1729 case Sema::NC_OverloadSet:
1730 Tok.setKind(tok::annot_overload_set);
1731 setExprAnnotation(Tok, Classification.getExpression());
1732 Tok.setAnnotationEndLoc(NameLoc);
1733 if (SS.isNotEmpty())
1734 Tok.setLocation(SS.getBeginLoc());
1735 PP.AnnotateCachedTokens(Tok);
1736 return ANK_Success;
1737
1738 case Sema::NC_NonType:
1739 Tok.setKind(tok::annot_non_type);
1740 setNonTypeAnnotation(Tok, Classification.getNonTypeDecl());
1741 Tok.setLocation(NameLoc);
1742 Tok.setAnnotationEndLoc(NameLoc);
1743 PP.AnnotateCachedTokens(Tok);
1744 if (SS.isNotEmpty())
1745 AnnotateScopeToken(SS, !WasScopeAnnotation);
1746 return ANK_Success;
1747
1748 case Sema::NC_UndeclaredNonType:
1749 case Sema::NC_DependentNonType:
1750 Tok.setKind(Classification.getKind() == Sema::NC_UndeclaredNonType
1751 ? tok::annot_non_type_undeclared
1752 : tok::annot_non_type_dependent);
1753 setIdentifierAnnotation(Tok, Name);
1754 Tok.setLocation(NameLoc);
1755 Tok.setAnnotationEndLoc(NameLoc);
1756 PP.AnnotateCachedTokens(Tok);
1757 if (SS.isNotEmpty())
1758 AnnotateScopeToken(SS, !WasScopeAnnotation);
1759 return ANK_Success;
1760
1761 case Sema::NC_TypeTemplate:
1762 if (Next.isNot(tok::less)) {
1763 // This may be a type template being used as a template template argument.
1764 if (SS.isNotEmpty())
1765 AnnotateScopeToken(SS, !WasScopeAnnotation);
1766 return ANK_TemplateName;
1767 }
1768 LLVM_FALLTHROUGH;
1769 case Sema::NC_VarTemplate:
1770 case Sema::NC_FunctionTemplate:
1771 case Sema::NC_UndeclaredTemplate: {
1772 // We have a type, variable or function template followed by '<'.
1773 ConsumeToken();
1774 UnqualifiedId Id;
1775 Id.setIdentifier(Name, NameLoc);
1776 if (AnnotateTemplateIdToken(
1777 TemplateTy::make(Classification.getTemplateName()),
1778 Classification.getTemplateNameKind(), SS, SourceLocation(), Id))
1779 return ANK_Error;
1780 return ANK_Success;
1781 }
1782 case Sema::NC_Concept: {
1783 UnqualifiedId Id;
1784 Id.setIdentifier(Name, NameLoc);
1785 if (Next.is(tok::less))
1786 // We have a concept name followed by '<'. Consume the identifier token so
1787 // we reach the '<' and annotate it.
1788 ConsumeToken();
1789 if (AnnotateTemplateIdToken(
1790 TemplateTy::make(Classification.getTemplateName()),
1791 Classification.getTemplateNameKind(), SS, SourceLocation(), Id,
1792 /*AllowTypeAnnotation=*/false, /*TypeConstraint=*/true))
1793 return ANK_Error;
1794 return ANK_Success;
1795 }
1796 }
1797
1798 // Unable to classify the name, but maybe we can annotate a scope specifier.
1799 if (SS.isNotEmpty())
1800 AnnotateScopeToken(SS, !WasScopeAnnotation);
1801 return ANK_Unresolved;
1802 }
1803
TryKeywordIdentFallback(bool DisableKeyword)1804 bool Parser::TryKeywordIdentFallback(bool DisableKeyword) {
1805 assert(Tok.isNot(tok::identifier));
1806 Diag(Tok, diag::ext_keyword_as_ident)
1807 << PP.getSpelling(Tok)
1808 << DisableKeyword;
1809 if (DisableKeyword)
1810 Tok.getIdentifierInfo()->revertTokenIDToIdentifier();
1811 Tok.setKind(tok::identifier);
1812 return true;
1813 }
1814
1815 /// TryAnnotateTypeOrScopeToken - If the current token position is on a
1816 /// typename (possibly qualified in C++) or a C++ scope specifier not followed
1817 /// by a typename, TryAnnotateTypeOrScopeToken will replace one or more tokens
1818 /// with a single annotation token representing the typename or C++ scope
1819 /// respectively.
1820 /// This simplifies handling of C++ scope specifiers and allows efficient
1821 /// backtracking without the need to re-parse and resolve nested-names and
1822 /// typenames.
1823 /// It will mainly be called when we expect to treat identifiers as typenames
1824 /// (if they are typenames). For example, in C we do not expect identifiers
1825 /// inside expressions to be treated as typenames so it will not be called
1826 /// for expressions in C.
1827 /// The benefit for C/ObjC is that a typename will be annotated and
1828 /// Actions.getTypeName will not be needed to be called again (e.g. getTypeName
1829 /// will not be called twice, once to check whether we have a declaration
1830 /// specifier, and another one to get the actual type inside
1831 /// ParseDeclarationSpecifiers).
1832 ///
1833 /// This returns true if an error occurred.
1834 ///
1835 /// Note that this routine emits an error if you call it with ::new or ::delete
1836 /// as the current tokens, so only call it in contexts where these are invalid.
TryAnnotateTypeOrScopeToken()1837 bool Parser::TryAnnotateTypeOrScopeToken() {
1838 assert((Tok.is(tok::identifier) || Tok.is(tok::coloncolon) ||
1839 Tok.is(tok::kw_typename) || Tok.is(tok::annot_cxxscope) ||
1840 Tok.is(tok::kw_decltype) || Tok.is(tok::annot_template_id) ||
1841 Tok.is(tok::kw___super)) &&
1842 "Cannot be a type or scope token!");
1843
1844 if (Tok.is(tok::kw_typename)) {
1845 // MSVC lets you do stuff like:
1846 // typename typedef T_::D D;
1847 //
1848 // We will consume the typedef token here and put it back after we have
1849 // parsed the first identifier, transforming it into something more like:
1850 // typename T_::D typedef D;
1851 if (getLangOpts().MSVCCompat && NextToken().is(tok::kw_typedef)) {
1852 Token TypedefToken;
1853 PP.Lex(TypedefToken);
1854 bool Result = TryAnnotateTypeOrScopeToken();
1855 PP.EnterToken(Tok, /*IsReinject=*/true);
1856 Tok = TypedefToken;
1857 if (!Result)
1858 Diag(Tok.getLocation(), diag::warn_expected_qualified_after_typename);
1859 return Result;
1860 }
1861
1862 // Parse a C++ typename-specifier, e.g., "typename T::type".
1863 //
1864 // typename-specifier:
1865 // 'typename' '::' [opt] nested-name-specifier identifier
1866 // 'typename' '::' [opt] nested-name-specifier template [opt]
1867 // simple-template-id
1868 SourceLocation TypenameLoc = ConsumeToken();
1869 CXXScopeSpec SS;
1870 if (ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
1871 /*ObjectHadErrors=*/false,
1872 /*EnteringContext=*/false, nullptr,
1873 /*IsTypename*/ true))
1874 return true;
1875 if (SS.isEmpty()) {
1876 if (Tok.is(tok::identifier) || Tok.is(tok::annot_template_id) ||
1877 Tok.is(tok::annot_decltype)) {
1878 // Attempt to recover by skipping the invalid 'typename'
1879 if (Tok.is(tok::annot_decltype) ||
1880 (!TryAnnotateTypeOrScopeToken() && Tok.isAnnotation())) {
1881 unsigned DiagID = diag::err_expected_qualified_after_typename;
1882 // MS compatibility: MSVC permits using known types with typename.
1883 // e.g. "typedef typename T* pointer_type"
1884 if (getLangOpts().MicrosoftExt)
1885 DiagID = diag::warn_expected_qualified_after_typename;
1886 Diag(Tok.getLocation(), DiagID);
1887 return false;
1888 }
1889 }
1890 if (Tok.isEditorPlaceholder())
1891 return true;
1892
1893 Diag(Tok.getLocation(), diag::err_expected_qualified_after_typename);
1894 return true;
1895 }
1896
1897 TypeResult Ty;
1898 if (Tok.is(tok::identifier)) {
1899 // FIXME: check whether the next token is '<', first!
1900 Ty = Actions.ActOnTypenameType(getCurScope(), TypenameLoc, SS,
1901 *Tok.getIdentifierInfo(),
1902 Tok.getLocation());
1903 } else if (Tok.is(tok::annot_template_id)) {
1904 TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok);
1905 if (!TemplateId->mightBeType()) {
1906 Diag(Tok, diag::err_typename_refers_to_non_type_template)
1907 << Tok.getAnnotationRange();
1908 return true;
1909 }
1910
1911 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
1912 TemplateId->NumArgs);
1913
1914 Ty = TemplateId->isInvalid()
1915 ? TypeError()
1916 : Actions.ActOnTypenameType(
1917 getCurScope(), TypenameLoc, SS, TemplateId->TemplateKWLoc,
1918 TemplateId->Template, TemplateId->Name,
1919 TemplateId->TemplateNameLoc, TemplateId->LAngleLoc,
1920 TemplateArgsPtr, TemplateId->RAngleLoc);
1921 } else {
1922 Diag(Tok, diag::err_expected_type_name_after_typename)
1923 << SS.getRange();
1924 return true;
1925 }
1926
1927 SourceLocation EndLoc = Tok.getLastLoc();
1928 Tok.setKind(tok::annot_typename);
1929 setTypeAnnotation(Tok, Ty);
1930 Tok.setAnnotationEndLoc(EndLoc);
1931 Tok.setLocation(TypenameLoc);
1932 PP.AnnotateCachedTokens(Tok);
1933 return false;
1934 }
1935
1936 // Remembers whether the token was originally a scope annotation.
1937 bool WasScopeAnnotation = Tok.is(tok::annot_cxxscope);
1938
1939 CXXScopeSpec SS;
1940 if (getLangOpts().CPlusPlus)
1941 if (ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
1942 /*ObjectHadErrors=*/false,
1943 /*EnteringContext*/ false))
1944 return true;
1945
1946 return TryAnnotateTypeOrScopeTokenAfterScopeSpec(SS, !WasScopeAnnotation);
1947 }
1948
1949 /// Try to annotate a type or scope token, having already parsed an
1950 /// optional scope specifier. \p IsNewScope should be \c true unless the scope
1951 /// specifier was extracted from an existing tok::annot_cxxscope annotation.
TryAnnotateTypeOrScopeTokenAfterScopeSpec(CXXScopeSpec & SS,bool IsNewScope)1952 bool Parser::TryAnnotateTypeOrScopeTokenAfterScopeSpec(CXXScopeSpec &SS,
1953 bool IsNewScope) {
1954 if (Tok.is(tok::identifier)) {
1955 // Determine whether the identifier is a type name.
1956 if (ParsedType Ty = Actions.getTypeName(
1957 *Tok.getIdentifierInfo(), Tok.getLocation(), getCurScope(), &SS,
1958 false, NextToken().is(tok::period), nullptr,
1959 /*IsCtorOrDtorName=*/false,
1960 /*NonTrivialTypeSourceInfo*/true,
1961 /*IsClassTemplateDeductionContext*/true)) {
1962 SourceLocation BeginLoc = Tok.getLocation();
1963 if (SS.isNotEmpty()) // it was a C++ qualified type name.
1964 BeginLoc = SS.getBeginLoc();
1965
1966 /// An Objective-C object type followed by '<' is a specialization of
1967 /// a parameterized class type or a protocol-qualified type.
1968 if (getLangOpts().ObjC && NextToken().is(tok::less) &&
1969 (Ty.get()->isObjCObjectType() ||
1970 Ty.get()->isObjCObjectPointerType())) {
1971 // Consume the name.
1972 SourceLocation IdentifierLoc = ConsumeToken();
1973 SourceLocation NewEndLoc;
1974 TypeResult NewType
1975 = parseObjCTypeArgsAndProtocolQualifiers(IdentifierLoc, Ty,
1976 /*consumeLastToken=*/false,
1977 NewEndLoc);
1978 if (NewType.isUsable())
1979 Ty = NewType.get();
1980 else if (Tok.is(tok::eof)) // Nothing to do here, bail out...
1981 return false;
1982 }
1983
1984 // This is a typename. Replace the current token in-place with an
1985 // annotation type token.
1986 Tok.setKind(tok::annot_typename);
1987 setTypeAnnotation(Tok, Ty);
1988 Tok.setAnnotationEndLoc(Tok.getLocation());
1989 Tok.setLocation(BeginLoc);
1990
1991 // In case the tokens were cached, have Preprocessor replace
1992 // them with the annotation token.
1993 PP.AnnotateCachedTokens(Tok);
1994 return false;
1995 }
1996
1997 if (!getLangOpts().CPlusPlus) {
1998 // If we're in C, we can't have :: tokens at all (the lexer won't return
1999 // them). If the identifier is not a type, then it can't be scope either,
2000 // just early exit.
2001 return false;
2002 }
2003
2004 // If this is a template-id, annotate with a template-id or type token.
2005 // FIXME: This appears to be dead code. We already have formed template-id
2006 // tokens when parsing the scope specifier; this can never form a new one.
2007 if (NextToken().is(tok::less)) {
2008 TemplateTy Template;
2009 UnqualifiedId TemplateName;
2010 TemplateName.setIdentifier(Tok.getIdentifierInfo(), Tok.getLocation());
2011 bool MemberOfUnknownSpecialization;
2012 if (TemplateNameKind TNK = Actions.isTemplateName(
2013 getCurScope(), SS,
2014 /*hasTemplateKeyword=*/false, TemplateName,
2015 /*ObjectType=*/nullptr, /*EnteringContext*/false, Template,
2016 MemberOfUnknownSpecialization)) {
2017 // Only annotate an undeclared template name as a template-id if the
2018 // following tokens have the form of a template argument list.
2019 if (TNK != TNK_Undeclared_template ||
2020 isTemplateArgumentList(1) != TPResult::False) {
2021 // Consume the identifier.
2022 ConsumeToken();
2023 if (AnnotateTemplateIdToken(Template, TNK, SS, SourceLocation(),
2024 TemplateName)) {
2025 // If an unrecoverable error occurred, we need to return true here,
2026 // because the token stream is in a damaged state. We may not
2027 // return a valid identifier.
2028 return true;
2029 }
2030 }
2031 }
2032 }
2033
2034 // The current token, which is either an identifier or a
2035 // template-id, is not part of the annotation. Fall through to
2036 // push that token back into the stream and complete the C++ scope
2037 // specifier annotation.
2038 }
2039
2040 if (Tok.is(tok::annot_template_id)) {
2041 TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok);
2042 if (TemplateId->Kind == TNK_Type_template) {
2043 // A template-id that refers to a type was parsed into a
2044 // template-id annotation in a context where we weren't allowed
2045 // to produce a type annotation token. Update the template-id
2046 // annotation token to a type annotation token now.
2047 AnnotateTemplateIdTokenAsType(SS);
2048 return false;
2049 }
2050 }
2051
2052 if (SS.isEmpty())
2053 return false;
2054
2055 // A C++ scope specifier that isn't followed by a typename.
2056 AnnotateScopeToken(SS, IsNewScope);
2057 return false;
2058 }
2059
2060 /// TryAnnotateScopeToken - Like TryAnnotateTypeOrScopeToken but only
2061 /// annotates C++ scope specifiers and template-ids. This returns
2062 /// true if there was an error that could not be recovered from.
2063 ///
2064 /// Note that this routine emits an error if you call it with ::new or ::delete
2065 /// as the current tokens, so only call it in contexts where these are invalid.
TryAnnotateCXXScopeToken(bool EnteringContext)2066 bool Parser::TryAnnotateCXXScopeToken(bool EnteringContext) {
2067 assert(getLangOpts().CPlusPlus &&
2068 "Call sites of this function should be guarded by checking for C++");
2069 assert(MightBeCXXScopeToken() && "Cannot be a type or scope token!");
2070
2071 CXXScopeSpec SS;
2072 if (ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
2073 /*ObjectHadErrors=*/false,
2074 EnteringContext))
2075 return true;
2076 if (SS.isEmpty())
2077 return false;
2078
2079 AnnotateScopeToken(SS, true);
2080 return false;
2081 }
2082
isTokenEqualOrEqualTypo()2083 bool Parser::isTokenEqualOrEqualTypo() {
2084 tok::TokenKind Kind = Tok.getKind();
2085 switch (Kind) {
2086 default:
2087 return false;
2088 case tok::ampequal: // &=
2089 case tok::starequal: // *=
2090 case tok::plusequal: // +=
2091 case tok::minusequal: // -=
2092 case tok::exclaimequal: // !=
2093 case tok::slashequal: // /=
2094 case tok::percentequal: // %=
2095 case tok::lessequal: // <=
2096 case tok::lesslessequal: // <<=
2097 case tok::greaterequal: // >=
2098 case tok::greatergreaterequal: // >>=
2099 case tok::caretequal: // ^=
2100 case tok::pipeequal: // |=
2101 case tok::equalequal: // ==
2102 Diag(Tok, diag::err_invalid_token_after_declarator_suggest_equal)
2103 << Kind
2104 << FixItHint::CreateReplacement(SourceRange(Tok.getLocation()), "=");
2105 LLVM_FALLTHROUGH;
2106 case tok::equal:
2107 return true;
2108 }
2109 }
2110
handleUnexpectedCodeCompletionToken()2111 SourceLocation Parser::handleUnexpectedCodeCompletionToken() {
2112 assert(Tok.is(tok::code_completion));
2113 PrevTokLocation = Tok.getLocation();
2114
2115 for (Scope *S = getCurScope(); S; S = S->getParent()) {
2116 if (S->getFlags() & Scope::FnScope) {
2117 Actions.CodeCompleteOrdinaryName(getCurScope(),
2118 Sema::PCC_RecoveryInFunction);
2119 cutOffParsing();
2120 return PrevTokLocation;
2121 }
2122
2123 if (S->getFlags() & Scope::ClassScope) {
2124 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Class);
2125 cutOffParsing();
2126 return PrevTokLocation;
2127 }
2128 }
2129
2130 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Namespace);
2131 cutOffParsing();
2132 return PrevTokLocation;
2133 }
2134
2135 // Code-completion pass-through functions
2136
CodeCompleteDirective(bool InConditional)2137 void Parser::CodeCompleteDirective(bool InConditional) {
2138 Actions.CodeCompletePreprocessorDirective(InConditional);
2139 }
2140
CodeCompleteInConditionalExclusion()2141 void Parser::CodeCompleteInConditionalExclusion() {
2142 Actions.CodeCompleteInPreprocessorConditionalExclusion(getCurScope());
2143 }
2144
CodeCompleteMacroName(bool IsDefinition)2145 void Parser::CodeCompleteMacroName(bool IsDefinition) {
2146 Actions.CodeCompletePreprocessorMacroName(IsDefinition);
2147 }
2148
CodeCompletePreprocessorExpression()2149 void Parser::CodeCompletePreprocessorExpression() {
2150 Actions.CodeCompletePreprocessorExpression();
2151 }
2152
CodeCompleteMacroArgument(IdentifierInfo * Macro,MacroInfo * MacroInfo,unsigned ArgumentIndex)2153 void Parser::CodeCompleteMacroArgument(IdentifierInfo *Macro,
2154 MacroInfo *MacroInfo,
2155 unsigned ArgumentIndex) {
2156 Actions.CodeCompletePreprocessorMacroArgument(getCurScope(), Macro, MacroInfo,
2157 ArgumentIndex);
2158 }
2159
CodeCompleteIncludedFile(llvm::StringRef Dir,bool IsAngled)2160 void Parser::CodeCompleteIncludedFile(llvm::StringRef Dir, bool IsAngled) {
2161 Actions.CodeCompleteIncludedFile(Dir, IsAngled);
2162 }
2163
CodeCompleteNaturalLanguage()2164 void Parser::CodeCompleteNaturalLanguage() {
2165 Actions.CodeCompleteNaturalLanguage();
2166 }
2167
ParseMicrosoftIfExistsCondition(IfExistsCondition & Result)2168 bool Parser::ParseMicrosoftIfExistsCondition(IfExistsCondition& Result) {
2169 assert((Tok.is(tok::kw___if_exists) || Tok.is(tok::kw___if_not_exists)) &&
2170 "Expected '__if_exists' or '__if_not_exists'");
2171 Result.IsIfExists = Tok.is(tok::kw___if_exists);
2172 Result.KeywordLoc = ConsumeToken();
2173
2174 BalancedDelimiterTracker T(*this, tok::l_paren);
2175 if (T.consumeOpen()) {
2176 Diag(Tok, diag::err_expected_lparen_after)
2177 << (Result.IsIfExists? "__if_exists" : "__if_not_exists");
2178 return true;
2179 }
2180
2181 // Parse nested-name-specifier.
2182 if (getLangOpts().CPlusPlus)
2183 ParseOptionalCXXScopeSpecifier(Result.SS, /*ObjectType=*/nullptr,
2184 /*ObjectHadErrors=*/false,
2185 /*EnteringContext=*/false);
2186
2187 // Check nested-name specifier.
2188 if (Result.SS.isInvalid()) {
2189 T.skipToEnd();
2190 return true;
2191 }
2192
2193 // Parse the unqualified-id.
2194 SourceLocation TemplateKWLoc; // FIXME: parsed, but unused.
2195 if (ParseUnqualifiedId(Result.SS, /*ObjectType=*/nullptr,
2196 /*ObjectHadErrors=*/false, /*EnteringContext*/ false,
2197 /*AllowDestructorName*/ true,
2198 /*AllowConstructorName*/ true,
2199 /*AllowDeductionGuide*/ false, &TemplateKWLoc,
2200 Result.Name)) {
2201 T.skipToEnd();
2202 return true;
2203 }
2204
2205 if (T.consumeClose())
2206 return true;
2207
2208 // Check if the symbol exists.
2209 switch (Actions.CheckMicrosoftIfExistsSymbol(getCurScope(), Result.KeywordLoc,
2210 Result.IsIfExists, Result.SS,
2211 Result.Name)) {
2212 case Sema::IER_Exists:
2213 Result.Behavior = Result.IsIfExists ? IEB_Parse : IEB_Skip;
2214 break;
2215
2216 case Sema::IER_DoesNotExist:
2217 Result.Behavior = !Result.IsIfExists ? IEB_Parse : IEB_Skip;
2218 break;
2219
2220 case Sema::IER_Dependent:
2221 Result.Behavior = IEB_Dependent;
2222 break;
2223
2224 case Sema::IER_Error:
2225 return true;
2226 }
2227
2228 return false;
2229 }
2230
ParseMicrosoftIfExistsExternalDeclaration()2231 void Parser::ParseMicrosoftIfExistsExternalDeclaration() {
2232 IfExistsCondition Result;
2233 if (ParseMicrosoftIfExistsCondition(Result))
2234 return;
2235
2236 BalancedDelimiterTracker Braces(*this, tok::l_brace);
2237 if (Braces.consumeOpen()) {
2238 Diag(Tok, diag::err_expected) << tok::l_brace;
2239 return;
2240 }
2241
2242 switch (Result.Behavior) {
2243 case IEB_Parse:
2244 // Parse declarations below.
2245 break;
2246
2247 case IEB_Dependent:
2248 llvm_unreachable("Cannot have a dependent external declaration");
2249
2250 case IEB_Skip:
2251 Braces.skipToEnd();
2252 return;
2253 }
2254
2255 // Parse the declarations.
2256 // FIXME: Support module import within __if_exists?
2257 while (Tok.isNot(tok::r_brace) && !isEofOrEom()) {
2258 ParsedAttributesWithRange attrs(AttrFactory);
2259 MaybeParseCXX11Attributes(attrs);
2260 DeclGroupPtrTy Result = ParseExternalDeclaration(attrs);
2261 if (Result && !getCurScope()->getParent())
2262 Actions.getASTConsumer().HandleTopLevelDecl(Result.get());
2263 }
2264 Braces.consumeClose();
2265 }
2266
2267 /// Parse a declaration beginning with the 'module' keyword or C++20
2268 /// context-sensitive keyword (optionally preceded by 'export').
2269 ///
2270 /// module-declaration: [Modules TS + P0629R0]
2271 /// 'export'[opt] 'module' module-name attribute-specifier-seq[opt] ';'
2272 ///
2273 /// global-module-fragment: [C++2a]
2274 /// 'module' ';' top-level-declaration-seq[opt]
2275 /// module-declaration: [C++2a]
2276 /// 'export'[opt] 'module' module-name module-partition[opt]
2277 /// attribute-specifier-seq[opt] ';'
2278 /// private-module-fragment: [C++2a]
2279 /// 'module' ':' 'private' ';' top-level-declaration-seq[opt]
ParseModuleDecl(bool IsFirstDecl)2280 Parser::DeclGroupPtrTy Parser::ParseModuleDecl(bool IsFirstDecl) {
2281 SourceLocation StartLoc = Tok.getLocation();
2282
2283 Sema::ModuleDeclKind MDK = TryConsumeToken(tok::kw_export)
2284 ? Sema::ModuleDeclKind::Interface
2285 : Sema::ModuleDeclKind::Implementation;
2286
2287 assert(
2288 (Tok.is(tok::kw_module) ||
2289 (Tok.is(tok::identifier) && Tok.getIdentifierInfo() == Ident_module)) &&
2290 "not a module declaration");
2291 SourceLocation ModuleLoc = ConsumeToken();
2292
2293 // Attributes appear after the module name, not before.
2294 // FIXME: Suggest moving the attributes later with a fixit.
2295 DiagnoseAndSkipCXX11Attributes();
2296
2297 // Parse a global-module-fragment, if present.
2298 if (getLangOpts().CPlusPlusModules && Tok.is(tok::semi)) {
2299 SourceLocation SemiLoc = ConsumeToken();
2300 if (!IsFirstDecl) {
2301 Diag(StartLoc, diag::err_global_module_introducer_not_at_start)
2302 << SourceRange(StartLoc, SemiLoc);
2303 return nullptr;
2304 }
2305 if (MDK == Sema::ModuleDeclKind::Interface) {
2306 Diag(StartLoc, diag::err_module_fragment_exported)
2307 << /*global*/0 << FixItHint::CreateRemoval(StartLoc);
2308 }
2309 return Actions.ActOnGlobalModuleFragmentDecl(ModuleLoc);
2310 }
2311
2312 // Parse a private-module-fragment, if present.
2313 if (getLangOpts().CPlusPlusModules && Tok.is(tok::colon) &&
2314 NextToken().is(tok::kw_private)) {
2315 if (MDK == Sema::ModuleDeclKind::Interface) {
2316 Diag(StartLoc, diag::err_module_fragment_exported)
2317 << /*private*/1 << FixItHint::CreateRemoval(StartLoc);
2318 }
2319 ConsumeToken();
2320 SourceLocation PrivateLoc = ConsumeToken();
2321 DiagnoseAndSkipCXX11Attributes();
2322 ExpectAndConsumeSemi(diag::err_private_module_fragment_expected_semi);
2323 return Actions.ActOnPrivateModuleFragmentDecl(ModuleLoc, PrivateLoc);
2324 }
2325
2326 SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Path;
2327 if (ParseModuleName(ModuleLoc, Path, /*IsImport*/false))
2328 return nullptr;
2329
2330 // Parse the optional module-partition.
2331 if (Tok.is(tok::colon)) {
2332 SourceLocation ColonLoc = ConsumeToken();
2333 SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Partition;
2334 if (ParseModuleName(ModuleLoc, Partition, /*IsImport*/false))
2335 return nullptr;
2336
2337 // FIXME: Support module partition declarations.
2338 Diag(ColonLoc, diag::err_unsupported_module_partition)
2339 << SourceRange(ColonLoc, Partition.back().second);
2340 // Recover by parsing as a non-partition.
2341 }
2342
2343 // We don't support any module attributes yet; just parse them and diagnose.
2344 ParsedAttributesWithRange Attrs(AttrFactory);
2345 MaybeParseCXX11Attributes(Attrs);
2346 ProhibitCXX11Attributes(Attrs, diag::err_attribute_not_module_attr);
2347
2348 ExpectAndConsumeSemi(diag::err_module_expected_semi);
2349
2350 return Actions.ActOnModuleDecl(StartLoc, ModuleLoc, MDK, Path, IsFirstDecl);
2351 }
2352
2353 /// Parse a module import declaration. This is essentially the same for
2354 /// Objective-C and the C++ Modules TS, except for the leading '@' (in ObjC)
2355 /// and the trailing optional attributes (in C++).
2356 ///
2357 /// [ObjC] @import declaration:
2358 /// '@' 'import' module-name ';'
2359 /// [ModTS] module-import-declaration:
2360 /// 'import' module-name attribute-specifier-seq[opt] ';'
2361 /// [C++2a] module-import-declaration:
2362 /// 'export'[opt] 'import' module-name
2363 /// attribute-specifier-seq[opt] ';'
2364 /// 'export'[opt] 'import' module-partition
2365 /// attribute-specifier-seq[opt] ';'
2366 /// 'export'[opt] 'import' header-name
2367 /// attribute-specifier-seq[opt] ';'
ParseModuleImport(SourceLocation AtLoc)2368 Decl *Parser::ParseModuleImport(SourceLocation AtLoc) {
2369 SourceLocation StartLoc = AtLoc.isInvalid() ? Tok.getLocation() : AtLoc;
2370
2371 SourceLocation ExportLoc;
2372 TryConsumeToken(tok::kw_export, ExportLoc);
2373
2374 assert((AtLoc.isInvalid() ? Tok.isOneOf(tok::kw_import, tok::identifier)
2375 : Tok.isObjCAtKeyword(tok::objc_import)) &&
2376 "Improper start to module import");
2377 bool IsObjCAtImport = Tok.isObjCAtKeyword(tok::objc_import);
2378 SourceLocation ImportLoc = ConsumeToken();
2379
2380 SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Path;
2381 Module *HeaderUnit = nullptr;
2382
2383 if (Tok.is(tok::header_name)) {
2384 // This is a header import that the preprocessor decided we should skip
2385 // because it was malformed in some way. Parse and ignore it; it's already
2386 // been diagnosed.
2387 ConsumeToken();
2388 } else if (Tok.is(tok::annot_header_unit)) {
2389 // This is a header import that the preprocessor mapped to a module import.
2390 HeaderUnit = reinterpret_cast<Module *>(Tok.getAnnotationValue());
2391 ConsumeAnnotationToken();
2392 } else if (getLangOpts().CPlusPlusModules && Tok.is(tok::colon)) {
2393 SourceLocation ColonLoc = ConsumeToken();
2394 if (ParseModuleName(ImportLoc, Path, /*IsImport*/true))
2395 return nullptr;
2396
2397 // FIXME: Support module partition import.
2398 Diag(ColonLoc, diag::err_unsupported_module_partition)
2399 << SourceRange(ColonLoc, Path.back().second);
2400 return nullptr;
2401 } else {
2402 if (ParseModuleName(ImportLoc, Path, /*IsImport*/true))
2403 return nullptr;
2404 }
2405
2406 ParsedAttributesWithRange Attrs(AttrFactory);
2407 MaybeParseCXX11Attributes(Attrs);
2408 // We don't support any module import attributes yet.
2409 ProhibitCXX11Attributes(Attrs, diag::err_attribute_not_import_attr);
2410
2411 if (PP.hadModuleLoaderFatalFailure()) {
2412 // With a fatal failure in the module loader, we abort parsing.
2413 cutOffParsing();
2414 return nullptr;
2415 }
2416
2417 DeclResult Import;
2418 if (HeaderUnit)
2419 Import =
2420 Actions.ActOnModuleImport(StartLoc, ExportLoc, ImportLoc, HeaderUnit);
2421 else if (!Path.empty())
2422 Import = Actions.ActOnModuleImport(StartLoc, ExportLoc, ImportLoc, Path);
2423 ExpectAndConsumeSemi(diag::err_module_expected_semi);
2424 if (Import.isInvalid())
2425 return nullptr;
2426
2427 // Using '@import' in framework headers requires modules to be enabled so that
2428 // the header is parseable. Emit a warning to make the user aware.
2429 if (IsObjCAtImport && AtLoc.isValid()) {
2430 auto &SrcMgr = PP.getSourceManager();
2431 auto *FE = SrcMgr.getFileEntryForID(SrcMgr.getFileID(AtLoc));
2432 if (FE && llvm::sys::path::parent_path(FE->getDir()->getName())
2433 .endswith(".framework"))
2434 Diags.Report(AtLoc, diag::warn_atimport_in_framework_header);
2435 }
2436
2437 return Import.get();
2438 }
2439
2440 /// Parse a C++ Modules TS / Objective-C module name (both forms use the same
2441 /// grammar).
2442 ///
2443 /// module-name:
2444 /// module-name-qualifier[opt] identifier
2445 /// module-name-qualifier:
2446 /// module-name-qualifier[opt] identifier '.'
ParseModuleName(SourceLocation UseLoc,SmallVectorImpl<std::pair<IdentifierInfo *,SourceLocation>> & Path,bool IsImport)2447 bool Parser::ParseModuleName(
2448 SourceLocation UseLoc,
2449 SmallVectorImpl<std::pair<IdentifierInfo *, SourceLocation>> &Path,
2450 bool IsImport) {
2451 // Parse the module path.
2452 while (true) {
2453 if (!Tok.is(tok::identifier)) {
2454 if (Tok.is(tok::code_completion)) {
2455 Actions.CodeCompleteModuleImport(UseLoc, Path);
2456 cutOffParsing();
2457 return true;
2458 }
2459
2460 Diag(Tok, diag::err_module_expected_ident) << IsImport;
2461 SkipUntil(tok::semi);
2462 return true;
2463 }
2464
2465 // Record this part of the module path.
2466 Path.push_back(std::make_pair(Tok.getIdentifierInfo(), Tok.getLocation()));
2467 ConsumeToken();
2468
2469 if (Tok.isNot(tok::period))
2470 return false;
2471
2472 ConsumeToken();
2473 }
2474 }
2475
2476 /// Try recover parser when module annotation appears where it must not
2477 /// be found.
2478 /// \returns false if the recover was successful and parsing may be continued, or
2479 /// true if parser must bail out to top level and handle the token there.
parseMisplacedModuleImport()2480 bool Parser::parseMisplacedModuleImport() {
2481 while (true) {
2482 switch (Tok.getKind()) {
2483 case tok::annot_module_end:
2484 // If we recovered from a misplaced module begin, we expect to hit a
2485 // misplaced module end too. Stay in the current context when this
2486 // happens.
2487 if (MisplacedModuleBeginCount) {
2488 --MisplacedModuleBeginCount;
2489 Actions.ActOnModuleEnd(Tok.getLocation(),
2490 reinterpret_cast<Module *>(
2491 Tok.getAnnotationValue()));
2492 ConsumeAnnotationToken();
2493 continue;
2494 }
2495 // Inform caller that recovery failed, the error must be handled at upper
2496 // level. This will generate the desired "missing '}' at end of module"
2497 // diagnostics on the way out.
2498 return true;
2499 case tok::annot_module_begin:
2500 // Recover by entering the module (Sema will diagnose).
2501 Actions.ActOnModuleBegin(Tok.getLocation(),
2502 reinterpret_cast<Module *>(
2503 Tok.getAnnotationValue()));
2504 ConsumeAnnotationToken();
2505 ++MisplacedModuleBeginCount;
2506 continue;
2507 case tok::annot_module_include:
2508 // Module import found where it should not be, for instance, inside a
2509 // namespace. Recover by importing the module.
2510 Actions.ActOnModuleInclude(Tok.getLocation(),
2511 reinterpret_cast<Module *>(
2512 Tok.getAnnotationValue()));
2513 ConsumeAnnotationToken();
2514 // If there is another module import, process it.
2515 continue;
2516 default:
2517 return false;
2518 }
2519 }
2520 return false;
2521 }
2522
diagnoseOverflow()2523 bool BalancedDelimiterTracker::diagnoseOverflow() {
2524 P.Diag(P.Tok, diag::err_bracket_depth_exceeded)
2525 << P.getLangOpts().BracketDepth;
2526 P.Diag(P.Tok, diag::note_bracket_depth);
2527 P.cutOffParsing();
2528 return true;
2529 }
2530
expectAndConsume(unsigned DiagID,const char * Msg,tok::TokenKind SkipToTok)2531 bool BalancedDelimiterTracker::expectAndConsume(unsigned DiagID,
2532 const char *Msg,
2533 tok::TokenKind SkipToTok) {
2534 LOpen = P.Tok.getLocation();
2535 if (P.ExpectAndConsume(Kind, DiagID, Msg)) {
2536 if (SkipToTok != tok::unknown)
2537 P.SkipUntil(SkipToTok, Parser::StopAtSemi);
2538 return true;
2539 }
2540
2541 if (getDepth() < P.getLangOpts().BracketDepth)
2542 return false;
2543
2544 return diagnoseOverflow();
2545 }
2546
diagnoseMissingClose()2547 bool BalancedDelimiterTracker::diagnoseMissingClose() {
2548 assert(!P.Tok.is(Close) && "Should have consumed closing delimiter");
2549
2550 if (P.Tok.is(tok::annot_module_end))
2551 P.Diag(P.Tok, diag::err_missing_before_module_end) << Close;
2552 else
2553 P.Diag(P.Tok, diag::err_expected) << Close;
2554 P.Diag(LOpen, diag::note_matching) << Kind;
2555
2556 // If we're not already at some kind of closing bracket, skip to our closing
2557 // token.
2558 if (P.Tok.isNot(tok::r_paren) && P.Tok.isNot(tok::r_brace) &&
2559 P.Tok.isNot(tok::r_square) &&
2560 P.SkipUntil(Close, FinalToken,
2561 Parser::StopAtSemi | Parser::StopBeforeMatch) &&
2562 P.Tok.is(Close))
2563 LClose = P.ConsumeAnyToken();
2564 return true;
2565 }
2566
skipToEnd()2567 void BalancedDelimiterTracker::skipToEnd() {
2568 P.SkipUntil(Close, Parser::StopBeforeMatch);
2569 consumeClose();
2570 }
2571