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/ASTLambda.h"
17	#include "clang/AST/DeclTemplate.h"
18	#include "clang/Basic/FileManager.h"
19	#include "clang/Parse/ParseDiagnostic.h"
20	#include "clang/Parse/RAIIObjectsForParser.h"
21	#include "clang/Sema/DeclSpec.h"
22	#include "clang/Sema/ParsedTemplate.h"
23	#include "clang/Sema/Scope.h"
24	#include "llvm/Support/Path.h"
25	#include "llvm/Support/TimeProfiler.h"
26	using namespace clang;
27
28
29	namespace {
30	/// A comment handler that passes comments found by the preprocessor
31	/// to the parser action.
32	class ActionCommentHandler : public CommentHandler {
33	Sema &S;
34
35	public:
36	explicit ActionCommentHandler(Sema &S) : S(S) { }
37
38	bool HandleComment(Preprocessor &PP, SourceRange Comment) override {
39	S.ActOnComment(Comment);
40	return false;
41	}
42	};
43	} // end anonymous namespace
44
45	IdentifierInfo *Parser::getSEHExceptKeyword() {
46	// __except is accepted as a (contextual) keyword
47	if (!Ident__except && (getLangOpts().MicrosoftExt || getLangOpts().Borland))
48	Ident__except = PP.getIdentifierInfo(Name: "__except");
49
50	return Ident__except;
51	}
52
53	Parser::Parser(Preprocessor &pp, Sema &actions, bool skipFunctionBodies)
54	: PP(pp), PreferredType(pp.isCodeCompletionEnabled()), Actions(actions),
55	Diags(PP.getDiagnostics()), GreaterThanIsOperator(true),
56	ColonIsSacred(false), InMessageExpression(false),
57	TemplateParameterDepth(0), ParsingInObjCContainer(false) {
58	SkipFunctionBodies = pp.isCodeCompletionEnabled() || skipFunctionBodies;
59	Tok.startToken();
60	Tok.setKind(tok::eof);
61	Actions.CurScope = nullptr;
62	NumCachedScopes = 0;
63	CurParsedObjCImpl = nullptr;
64
65	// Add #pragma handlers. These are removed and destroyed in the
66	// destructor.
67	initializePragmaHandlers();
68
69	CommentSemaHandler.reset(p: new ActionCommentHandler(actions));
70	PP.addCommentHandler(Handler: CommentSemaHandler.get());
71
72	PP.setCodeCompletionHandler(*this);
73
74	Actions.ParseTypeFromStringCallback =
75	[this](StringRef TypeStr, StringRef Context, SourceLocation IncludeLoc) {
76	return this->ParseTypeFromString(TypeStr, Context, IncludeLoc);
77	};
78	}
79
80	DiagnosticBuilder Parser::Diag(SourceLocation Loc, unsigned DiagID) {
81	return Diags.Report(Loc, DiagID);
82	}
83
84	DiagnosticBuilder Parser::Diag(const Token &Tok, unsigned DiagID) {
85	return Diag(Loc: Tok.getLocation(), DiagID);
86	}
87
88	/// Emits a diagnostic suggesting parentheses surrounding a
89	/// given range.
90	///
91	/// \param Loc The location where we'll emit the diagnostic.
92	/// \param DK The kind of diagnostic to emit.
93	/// \param ParenRange Source range enclosing code that should be parenthesized.
94	void Parser::SuggestParentheses(SourceLocation Loc, unsigned DK,
95	SourceRange ParenRange) {
96	SourceLocation EndLoc = PP.getLocForEndOfToken(Loc: ParenRange.getEnd());
97	if (!ParenRange.getEnd().isFileID() || EndLoc.isInvalid()) {
98	// We can't display the parentheses, so just dig the
99	// warning/error and return.
100	Diag(Loc, DiagID: DK);
101	return;
102	}
103
104	Diag(Loc, DiagID: DK)
105	<< FixItHint::CreateInsertion(InsertionLoc: ParenRange.getBegin(), Code: "(")
106	<< FixItHint::CreateInsertion(InsertionLoc: EndLoc, Code: ")");
107	}
108
109	static bool IsCommonTypo(tok::TokenKind ExpectedTok, const Token &Tok) {
110	switch (ExpectedTok) {
111	case tok::semi:
112	return Tok.is(K: tok::colon) || Tok.is(K: tok::comma); // : or , for ;
113	default: return false;
114	}
115	}
116
117	bool Parser::ExpectAndConsume(tok::TokenKind ExpectedTok, unsigned DiagID,
118	StringRef Msg) {
119	if (Tok.is(K: ExpectedTok) || Tok.is(K: tok::code_completion)) {
120	ConsumeAnyToken();
121	return false;
122	}
123
124	// Detect common single-character typos and resume.
125	if (IsCommonTypo(ExpectedTok, Tok)) {
126	SourceLocation Loc = Tok.getLocation();
127	{
128	DiagnosticBuilder DB = Diag(Loc, DiagID);
129	DB << FixItHint::CreateReplacement(
130	RemoveRange: SourceRange(Loc), Code: tok::getPunctuatorSpelling(Kind: ExpectedTok));
131	if (DiagID == diag::err_expected)
132	DB << ExpectedTok;
133	else if (DiagID == diag::err_expected_after)
134	DB << Msg << ExpectedTok;
135	else
136	DB << Msg;
137	}
138
139	// Pretend there wasn't a problem.
140	ConsumeAnyToken();
141	return false;
142	}
143
144	SourceLocation EndLoc = PP.getLocForEndOfToken(Loc: PrevTokLocation);
145	const char *Spelling = nullptr;
146	if (EndLoc.isValid())
147	Spelling = tok::getPunctuatorSpelling(Kind: ExpectedTok);
148
149	DiagnosticBuilder DB =
150	Spelling
151	? Diag(Loc: EndLoc, DiagID) << FixItHint::CreateInsertion(InsertionLoc: EndLoc, Code: Spelling)
152	: Diag(Tok, DiagID);
153	if (DiagID == diag::err_expected)
154	DB << ExpectedTok;
155	else if (DiagID == diag::err_expected_after)
156	DB << Msg << ExpectedTok;
157	else
158	DB << Msg;
159
160	return true;
161	}
162
163	bool Parser::ExpectAndConsumeSemi(unsigned DiagID, StringRef TokenUsed) {
164	if (TryConsumeToken(Expected: tok::semi))
165	return false;
166
167	if (Tok.is(K: tok::code_completion)) {
168	handleUnexpectedCodeCompletionToken();
169	return false;
170	}
171
172	if ((Tok.is(K: tok::r_paren) || Tok.is(K: tok::r_square)) &&
173	NextToken().is(K: tok::semi)) {
174	Diag(Tok, diag::err_extraneous_token_before_semi)
175	<< PP.getSpelling(Tok)
176	<< FixItHint::CreateRemoval(Tok.getLocation());
177	ConsumeAnyToken(); // The ')' or ']'.
178	ConsumeToken(); // The ';'.
179	return false;
180	}
181
182	return ExpectAndConsume(ExpectedTok: tok::semi, DiagID , Msg: TokenUsed);
183	}
184
185	void Parser::ConsumeExtraSemi(ExtraSemiKind Kind, DeclSpec::TST TST) {
186	if (!Tok.is(K: tok::semi)) return;
187
188	bool HadMultipleSemis = false;
189	SourceLocation StartLoc = Tok.getLocation();
190	SourceLocation EndLoc = Tok.getLocation();
191	ConsumeToken();
192
193	while ((Tok.is(K: tok::semi) && !Tok.isAtStartOfLine())) {
194	HadMultipleSemis = true;
195	EndLoc = Tok.getLocation();
196	ConsumeToken();
197	}
198
199	// C++11 allows extra semicolons at namespace scope, but not in any of the
200	// other contexts.
201	if (Kind == OutsideFunction && getLangOpts().CPlusPlus) {
202	if (getLangOpts().CPlusPlus11)
203	Diag(StartLoc, diag::warn_cxx98_compat_top_level_semi)
204	<< FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
205	else
206	Diag(StartLoc, diag::ext_extra_semi_cxx11)
207	<< FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
208	return;
209	}
210
211	if (Kind != AfterMemberFunctionDefinition || HadMultipleSemis)
212	Diag(StartLoc, diag::ext_extra_semi)
213	<< Kind << DeclSpec::getSpecifierName(TST,
214	Actions.getASTContext().getPrintingPolicy())
215	<< FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
216	else
217	// A single semicolon is valid after a member function definition.
218	Diag(StartLoc, diag::warn_extra_semi_after_mem_fn_def)
219	<< FixItHint::CreateRemoval(SourceRange(StartLoc, EndLoc));
220	}
221
222	bool Parser::expectIdentifier() {
223	if (Tok.is(K: tok::identifier))
224	return false;
225	if (const auto *II = Tok.getIdentifierInfo()) {
226	if (II->isCPlusPlusKeyword(LangOpts: getLangOpts())) {
227	Diag(Tok, diag::err_expected_token_instead_of_objcxx_keyword)
228	<< tok::identifier << Tok.getIdentifierInfo();
229	// Objective-C++: Recover by treating this keyword as a valid identifier.
230	return false;
231	}
232	}
233	Diag(Tok, diag::err_expected) << tok::identifier;
234	return true;
235	}
236
237	void Parser::checkCompoundToken(SourceLocation FirstTokLoc,
238	tok::TokenKind FirstTokKind, CompoundToken Op) {
239	if (FirstTokLoc.isInvalid())
240	return;
241	SourceLocation SecondTokLoc = Tok.getLocation();
242
243	// If either token is in a macro, we expect both tokens to come from the same
244	// macro expansion.
245	if ((FirstTokLoc.isMacroID() || SecondTokLoc.isMacroID()) &&
246	PP.getSourceManager().getFileID(SpellingLoc: FirstTokLoc) !=
247	PP.getSourceManager().getFileID(SpellingLoc: SecondTokLoc)) {
248	Diag(FirstTokLoc, diag::warn_compound_token_split_by_macro)
249	<< (FirstTokKind == Tok.getKind()) << FirstTokKind << Tok.getKind()
250	<< static_cast<int>(Op) << SourceRange(FirstTokLoc);
251	Diag(SecondTokLoc, diag::note_compound_token_split_second_token_here)
252	<< (FirstTokKind == Tok.getKind()) << Tok.getKind()
253	<< SourceRange(SecondTokLoc);
254	return;
255	}
256
257	// We expect the tokens to abut.
258	if (Tok.hasLeadingSpace() || Tok.isAtStartOfLine()) {
259	SourceLocation SpaceLoc = PP.getLocForEndOfToken(Loc: FirstTokLoc);
260	if (SpaceLoc.isInvalid())
261	SpaceLoc = FirstTokLoc;
262	Diag(SpaceLoc, diag::warn_compound_token_split_by_whitespace)
263	<< (FirstTokKind == Tok.getKind()) << FirstTokKind << Tok.getKind()
264	<< static_cast<int>(Op) << SourceRange(FirstTokLoc, SecondTokLoc);
265	return;
266	}
267	}
268
269	//===----------------------------------------------------------------------===//
270	// Error recovery.
271	//===----------------------------------------------------------------------===//
272
273	static bool HasFlagsSet(Parser::SkipUntilFlags L, Parser::SkipUntilFlags R) {
274	return (static_cast<unsigned>(L) & static_cast<unsigned>(R)) != 0;
275	}
276
277	/// SkipUntil - Read tokens until we get to the specified token, then consume
278	/// it (unless no flag StopBeforeMatch). Because we cannot guarantee that the
279	/// token will ever occur, this skips to the next token, or to some likely
280	/// good stopping point. If StopAtSemi is true, skipping will stop at a ';'
281	/// character.
282	///
283	/// If SkipUntil finds the specified token, it returns true, otherwise it
284	/// returns false.
285	bool Parser::SkipUntil(ArrayRef<tok::TokenKind> Toks, SkipUntilFlags Flags) {
286	// We always want this function to skip at least one token if the first token
287	// isn't T and if not at EOF.
288	bool isFirstTokenSkipped = true;
289	while (true) {
290	// If we found one of the tokens, stop and return true.
291	for (unsigned i = 0, NumToks = Toks.size(); i != NumToks; ++i) {
292	if (Tok.is(K: Toks[i])) {
293	if (HasFlagsSet(L: Flags, R: StopBeforeMatch)) {
294	// Noop, don't consume the token.
295	} else {
296	ConsumeAnyToken();
297	}
298	return true;
299	}
300	}
301
302	// Important special case: The caller has given up and just wants us to
303	// skip the rest of the file. Do this without recursing, since we can
304	// get here precisely because the caller detected too much recursion.
305	if (Toks.size() == 1 && Toks[0] == tok::eof &&
306	!HasFlagsSet(L: Flags, R: StopAtSemi) &&
307	!HasFlagsSet(L: Flags, R: StopAtCodeCompletion)) {
308	while (Tok.isNot(K: tok::eof))
309	ConsumeAnyToken();
310	return true;
311	}
312
313	switch (Tok.getKind()) {
314	case tok::eof:
315	// Ran out of tokens.
316	return false;
317
318	case tok::annot_pragma_openmp:
319	case tok::annot_attr_openmp:
320	case tok::annot_pragma_openmp_end:
321	// Stop before an OpenMP pragma boundary.
322	if (OpenMPDirectiveParsing)
323	return false;
324	ConsumeAnnotationToken();
325	break;
326	case tok::annot_pragma_openacc:
327	case tok::annot_pragma_openacc_end:
328	// Stop before an OpenACC pragma boundary.
329	if (OpenACCDirectiveParsing)
330	return false;
331	ConsumeAnnotationToken();
332	break;
333	case tok::annot_module_begin:
334	case tok::annot_module_end:
335	case tok::annot_module_include:
336	case tok::annot_repl_input_end:
337	// Stop before we change submodules. They generally indicate a "good"
338	// place to pick up parsing again (except in the special case where
339	// we're trying to skip to EOF).
340	return false;
341
342	case tok::code_completion:
343	if (!HasFlagsSet(L: Flags, R: StopAtCodeCompletion))
344	handleUnexpectedCodeCompletionToken();
345	return false;
346
347	case tok::l_paren:
348	// Recursively skip properly-nested parens.
349	ConsumeParen();
350	if (HasFlagsSet(L: Flags, R: StopAtCodeCompletion))
351	SkipUntil(T: tok::r_paren, Flags: StopAtCodeCompletion);
352	else
353	SkipUntil(T: tok::r_paren);
354	break;
355	case tok::l_square:
356	// Recursively skip properly-nested square brackets.
357	ConsumeBracket();
358	if (HasFlagsSet(L: Flags, R: StopAtCodeCompletion))
359	SkipUntil(T: tok::r_square, Flags: StopAtCodeCompletion);
360	else
361	SkipUntil(T: tok::r_square);
362	break;
363	case tok::l_brace:
364	// Recursively skip properly-nested braces.
365	ConsumeBrace();
366	if (HasFlagsSet(L: Flags, R: StopAtCodeCompletion))
367	SkipUntil(T: tok::r_brace, Flags: StopAtCodeCompletion);
368	else
369	SkipUntil(T: tok::r_brace);
370	break;
371	case tok::question:
372	// Recursively skip ? ... : pairs; these function as brackets. But
373	// still stop at a semicolon if requested.
374	ConsumeToken();
375	SkipUntil(T: tok::colon,
376	Flags: SkipUntilFlags(unsigned(Flags) &
377	unsigned(StopAtCodeCompletion | StopAtSemi)));
378	break;
379
380	// Okay, we found a ']' or '}' or ')', which we think should be balanced.
381	// Since the user wasn't looking for this token (if they were, it would
382	// already be handled), this isn't balanced. If there is a LHS token at a
383	// higher level, we will assume that this matches the unbalanced token
384	// and return it. Otherwise, this is a spurious RHS token, which we skip.
385	case tok::r_paren:
386	if (ParenCount && !isFirstTokenSkipped)
387	return false; // Matches something.
388	ConsumeParen();
389	break;
390	case tok::r_square:
391	if (BracketCount && !isFirstTokenSkipped)
392	return false; // Matches something.
393	ConsumeBracket();
394	break;
395	case tok::r_brace:
396	if (BraceCount && !isFirstTokenSkipped)
397	return false; // Matches something.
398	ConsumeBrace();
399	break;
400
401	case tok::semi:
402	if (HasFlagsSet(L: Flags, R: StopAtSemi))
403	return false;
404	[[fallthrough]];
405	default:
406	// Skip this token.
407	ConsumeAnyToken();
408	break;
409	}
410	isFirstTokenSkipped = false;
411	}
412	}
413
414	//===----------------------------------------------------------------------===//
415	// Scope manipulation
416	//===----------------------------------------------------------------------===//
417
418	/// EnterScope - Start a new scope.
419	void Parser::EnterScope(unsigned ScopeFlags) {
420	if (NumCachedScopes) {
421	Scope *N = ScopeCache[--NumCachedScopes];
422	N->Init(parent: getCurScope(), flags: ScopeFlags);
423	Actions.CurScope = N;
424	} else {
425	Actions.CurScope = new Scope(getCurScope(), ScopeFlags, Diags);
426	}
427	}
428
429	/// ExitScope - Pop a scope off the scope stack.
430	void Parser::ExitScope() {
431	assert(getCurScope() && "Scope imbalance!");
432
433	// Inform the actions module that this scope is going away if there are any
434	// decls in it.
435	Actions.ActOnPopScope(Loc: Tok.getLocation(), S: getCurScope());
436
437	Scope *OldScope = getCurScope();
438	Actions.CurScope = OldScope->getParent();
439
440	if (NumCachedScopes == ScopeCacheSize)
441	delete OldScope;
442	else
443	ScopeCache[NumCachedScopes++] = OldScope;
444	}
445
446	/// Set the flags for the current scope to ScopeFlags. If ManageFlags is false,
447	/// this object does nothing.
448	Parser::ParseScopeFlags::ParseScopeFlags(Parser *Self, unsigned ScopeFlags,
449	bool ManageFlags)
450	: CurScope(ManageFlags ? Self->getCurScope() : nullptr) {
451	if (CurScope) {
452	OldFlags = CurScope->getFlags();
453	CurScope->setFlags(ScopeFlags);
454	}
455	}
456
457	/// Restore the flags for the current scope to what they were before this
458	/// object overrode them.
459	Parser::ParseScopeFlags::~ParseScopeFlags() {
460	if (CurScope)
461	CurScope->setFlags(OldFlags);
462	}
463
464
465	//===----------------------------------------------------------------------===//
466	// C99 6.9: External Definitions.
467	//===----------------------------------------------------------------------===//
468
469	Parser::~Parser() {
470	// If we still have scopes active, delete the scope tree.
471	delete getCurScope();
472	Actions.CurScope = nullptr;
473
474	// Free the scope cache.
475	for (unsigned i = 0, e = NumCachedScopes; i != e; ++i)
476	delete ScopeCache[i];
477
478	resetPragmaHandlers();
479
480	PP.removeCommentHandler(Handler: CommentSemaHandler.get());
481
482	PP.clearCodeCompletionHandler();
483
484	DestroyTemplateIds();
485	}
486
487	/// Initialize - Warm up the parser.
488	///
489	void Parser::Initialize() {
490	// Create the translation unit scope. Install it as the current scope.
491	assert(getCurScope() == nullptr && "A scope is already active?");
492	EnterScope(ScopeFlags: Scope::DeclScope);
493	Actions.ActOnTranslationUnitScope(S: getCurScope());
494
495	// Initialization for Objective-C context sensitive keywords recognition.
496	// Referenced in Parser::ParseObjCTypeQualifierList.
497	if (getLangOpts().ObjC) {
498	ObjCTypeQuals[objc_in] = &PP.getIdentifierTable().get(Name: "in");
499	ObjCTypeQuals[objc_out] = &PP.getIdentifierTable().get(Name: "out");
500	ObjCTypeQuals[objc_inout] = &PP.getIdentifierTable().get(Name: "inout");
501	ObjCTypeQuals[objc_oneway] = &PP.getIdentifierTable().get(Name: "oneway");
502	ObjCTypeQuals[objc_bycopy] = &PP.getIdentifierTable().get(Name: "bycopy");
503	ObjCTypeQuals[objc_byref] = &PP.getIdentifierTable().get(Name: "byref");
504	ObjCTypeQuals[objc_nonnull] = &PP.getIdentifierTable().get(Name: "nonnull");
505	ObjCTypeQuals[objc_nullable] = &PP.getIdentifierTable().get(Name: "nullable");
506	ObjCTypeQuals[objc_null_unspecified]
507	= &PP.getIdentifierTable().get(Name: "null_unspecified");
508	}
509
510	Ident_instancetype = nullptr;
511	Ident_final = nullptr;
512	Ident_sealed = nullptr;
513	Ident_abstract = nullptr;
514	Ident_override = nullptr;
515	Ident_GNU_final = nullptr;
516	Ident_import = nullptr;
517	Ident_module = nullptr;
518
519	Ident_super = &PP.getIdentifierTable().get(Name: "super");
520
521	Ident_vector = nullptr;
522	Ident_bool = nullptr;
523	Ident_Bool = nullptr;
524	Ident_pixel = nullptr;
525	if (getLangOpts().AltiVec || getLangOpts().ZVector) {
526	Ident_vector = &PP.getIdentifierTable().get(Name: "vector");
527	Ident_bool = &PP.getIdentifierTable().get(Name: "bool");
528	Ident_Bool = &PP.getIdentifierTable().get(Name: "_Bool");
529	}
530	if (getLangOpts().AltiVec)
531	Ident_pixel = &PP.getIdentifierTable().get(Name: "pixel");
532
533	Ident_introduced = nullptr;
534	Ident_deprecated = nullptr;
535	Ident_obsoleted = nullptr;
536	Ident_unavailable = nullptr;
537	Ident_strict = nullptr;
538	Ident_replacement = nullptr;
539
540	Ident_language = Ident_defined_in = Ident_generated_declaration = Ident_USR =
541	nullptr;
542
543	Ident__except = nullptr;
544
545	Ident__exception_code = Ident__exception_info = nullptr;
546	Ident__abnormal_termination = Ident___exception_code = nullptr;
547	Ident___exception_info = Ident___abnormal_termination = nullptr;
548	Ident_GetExceptionCode = Ident_GetExceptionInfo = nullptr;
549	Ident_AbnormalTermination = nullptr;
550
551	if(getLangOpts().Borland) {
552	Ident__exception_info = PP.getIdentifierInfo(Name: "_exception_info");
553	Ident___exception_info = PP.getIdentifierInfo(Name: "__exception_info");
554	Ident_GetExceptionInfo = PP.getIdentifierInfo(Name: "GetExceptionInformation");
555	Ident__exception_code = PP.getIdentifierInfo(Name: "_exception_code");
556	Ident___exception_code = PP.getIdentifierInfo(Name: "__exception_code");
557	Ident_GetExceptionCode = PP.getIdentifierInfo(Name: "GetExceptionCode");
558	Ident__abnormal_termination = PP.getIdentifierInfo(Name: "_abnormal_termination");
559	Ident___abnormal_termination = PP.getIdentifierInfo(Name: "__abnormal_termination");
560	Ident_AbnormalTermination = PP.getIdentifierInfo(Name: "AbnormalTermination");
561
562	PP.SetPoisonReason(Ident__exception_code,diag::err_seh___except_block);
563	PP.SetPoisonReason(Ident___exception_code,diag::err_seh___except_block);
564	PP.SetPoisonReason(Ident_GetExceptionCode,diag::err_seh___except_block);
565	PP.SetPoisonReason(Ident__exception_info,diag::err_seh___except_filter);
566	PP.SetPoisonReason(Ident___exception_info,diag::err_seh___except_filter);
567	PP.SetPoisonReason(Ident_GetExceptionInfo,diag::err_seh___except_filter);
568	PP.SetPoisonReason(Ident__abnormal_termination,diag::err_seh___finally_block);
569	PP.SetPoisonReason(Ident___abnormal_termination,diag::err_seh___finally_block);
570	PP.SetPoisonReason(Ident_AbnormalTermination,diag::err_seh___finally_block);
571	}
572
573	if (getLangOpts().CPlusPlusModules) {
574	Ident_import = PP.getIdentifierInfo(Name: "import");
575	Ident_module = PP.getIdentifierInfo(Name: "module");
576	}
577
578	Actions.Initialize();
579
580	// Prime the lexer look-ahead.
581	ConsumeToken();
582	}
583
584	void Parser::DestroyTemplateIds() {
585	for (TemplateIdAnnotation *Id : TemplateIds)
586	Id->Destroy();
587	TemplateIds.clear();
588	}
589
590	/// Parse the first top-level declaration in a translation unit.
591	///
592	/// translation-unit:
593	/// [C] external-declaration
594	/// [C] translation-unit external-declaration
595	/// [C++] top-level-declaration-seq[opt]
596	/// [C++20] global-module-fragment[opt] module-declaration
597	/// top-level-declaration-seq[opt] private-module-fragment[opt]
598	///
599	/// Note that in C, it is an error if there is no first declaration.
600	bool Parser::ParseFirstTopLevelDecl(DeclGroupPtrTy &Result,
601	Sema::ModuleImportState &ImportState) {
602	Actions.ActOnStartOfTranslationUnit();
603
604	// For C++20 modules, a module decl must be the first in the TU. We also
605	// need to track module imports.
606	ImportState = Sema::ModuleImportState::FirstDecl;
607	bool NoTopLevelDecls = ParseTopLevelDecl(Result, ImportState);
608
609	// C11 6.9p1 says translation units must have at least one top-level
610	// declaration. C++ doesn't have this restriction. We also don't want to
611	// complain if we have a precompiled header, although technically if the PCH
612	// is empty we should still emit the (pedantic) diagnostic.
613	// If the main file is a header, we're only pretending it's a TU; don't warn.
614	if (NoTopLevelDecls && !Actions.getASTContext().getExternalSource() &&
615	!getLangOpts().CPlusPlus && !getLangOpts().IsHeaderFile)
616	Diag(diag::ext_empty_translation_unit);
617
618	return NoTopLevelDecls;
619	}
620
621	/// ParseTopLevelDecl - Parse one top-level declaration, return whatever the
622	/// action tells us to. This returns true if the EOF was encountered.
623	///
624	/// top-level-declaration:
625	/// declaration
626	/// [C++20] module-import-declaration
627	bool Parser::ParseTopLevelDecl(DeclGroupPtrTy &Result,
628	Sema::ModuleImportState &ImportState) {
629	DestroyTemplateIdAnnotationsRAIIObj CleanupRAII(*this);
630
631	// Skip over the EOF token, flagging end of previous input for incremental
632	// processing
633	if (PP.isIncrementalProcessingEnabled() && Tok.is(K: tok::eof))
634	ConsumeToken();
635
636	Result = nullptr;
637	switch (Tok.getKind()) {
638	case tok::annot_pragma_unused:
639	HandlePragmaUnused();
640	return false;
641
642	case tok::kw_export:
643	switch (NextToken().getKind()) {
644	case tok::kw_module:
645	goto module_decl;
646
647	// Note: no need to handle kw_import here. We only form kw_import under
648	// the Standard C++ Modules, and in that case 'export import' is parsed as
649	// an export-declaration containing an import-declaration.
650
651	// Recognize context-sensitive C++20 'export module' and 'export import'
652	// declarations.
653	case tok::identifier: {
654	IdentifierInfo *II = NextToken().getIdentifierInfo();
655	if ((II == Ident_module || II == Ident_import) &&
656	GetLookAheadToken(N: 2).isNot(K: tok::coloncolon)) {
657	if (II == Ident_module)
658	goto module_decl;
659	else
660	goto import_decl;
661	}
662	break;
663	}
664
665	default:
666	break;
667	}
668	break;
669
670	case tok::kw_module:
671	module_decl:
672	Result = ParseModuleDecl(ImportState);
673	return false;
674
675	case tok::kw_import:
676	import_decl: {
677	Decl *ImportDecl = ParseModuleImport(AtLoc: SourceLocation(), ImportState);
678	Result = Actions.ConvertDeclToDeclGroup(Ptr: ImportDecl);
679	return false;
680	}
681
682	case tok::annot_module_include: {
683	auto Loc = Tok.getLocation();
684	Module *Mod = reinterpret_cast<Module *>(Tok.getAnnotationValue());
685	// FIXME: We need a better way to disambiguate C++ clang modules and
686	// standard C++ modules.
687	if (!getLangOpts().CPlusPlusModules || !Mod->isHeaderUnit())
688	Actions.ActOnAnnotModuleInclude(DirectiveLoc: Loc, Mod);
689	else {
690	DeclResult Import =
691	Actions.ActOnModuleImport(StartLoc: Loc, ExportLoc: SourceLocation(), ImportLoc: Loc, M: Mod);
692	Decl *ImportDecl = Import.isInvalid() ? nullptr : Import.get();
693	Result = Actions.ConvertDeclToDeclGroup(Ptr: ImportDecl);
694	}
695	ConsumeAnnotationToken();
696	return false;
697	}
698
699	case tok::annot_module_begin:
700	Actions.ActOnAnnotModuleBegin(
701	DirectiveLoc: Tok.getLocation(),
702	Mod: reinterpret_cast<Module *>(Tok.getAnnotationValue()));
703	ConsumeAnnotationToken();
704	ImportState = Sema::ModuleImportState::NotACXX20Module;
705	return false;
706
707	case tok::annot_module_end:
708	Actions.ActOnAnnotModuleEnd(
709	DirectiveLoc: Tok.getLocation(),
710	Mod: reinterpret_cast<Module *>(Tok.getAnnotationValue()));
711	ConsumeAnnotationToken();
712	ImportState = Sema::ModuleImportState::NotACXX20Module;
713	return false;
714
715	case tok::eof:
716	case tok::annot_repl_input_end:
717	// Check whether -fmax-tokens= was reached.
718	if (PP.getMaxTokens() != 0 && PP.getTokenCount() > PP.getMaxTokens()) {
719	PP.Diag(Tok.getLocation(), diag::warn_max_tokens_total)
720	<< PP.getTokenCount() << PP.getMaxTokens();
721	SourceLocation OverrideLoc = PP.getMaxTokensOverrideLoc();
722	if (OverrideLoc.isValid()) {
723	PP.Diag(OverrideLoc, diag::note_max_tokens_total_override);
724	}
725	}
726
727	// Late template parsing can begin.
728	Actions.SetLateTemplateParser(LTP: LateTemplateParserCallback, LTPCleanup: nullptr, P: this);
729	Actions.ActOnEndOfTranslationUnit();
730	//else don't tell Sema that we ended parsing: more input might come.
731	return true;
732
733	case tok::identifier:
734	// C++2a [basic.link]p3:
735	// A token sequence beginning with 'export[opt] module' or
736	// 'export[opt] import' and not immediately followed by '::'
737	// is never interpreted as the declaration of a top-level-declaration.
738	if ((Tok.getIdentifierInfo() == Ident_module ||
739	Tok.getIdentifierInfo() == Ident_import) &&
740	NextToken().isNot(K: tok::coloncolon)) {
741	if (Tok.getIdentifierInfo() == Ident_module)
742	goto module_decl;
743	else
744	goto import_decl;
745	}
746	break;
747
748	default:
749	break;
750	}
751
752	ParsedAttributes DeclAttrs(AttrFactory);
753	ParsedAttributes DeclSpecAttrs(AttrFactory);
754	// GNU attributes are applied to the declaration specification while the
755	// standard attributes are applied to the declaration. We parse the two
756	// attribute sets into different containters so we can apply them during
757	// the regular parsing process.
758	while (MaybeParseCXX11Attributes(Attrs&: DeclAttrs) ||
759	MaybeParseGNUAttributes(Attrs&: DeclSpecAttrs))
760	;
761
762	Result = ParseExternalDeclaration(DeclAttrs, DeclSpecAttrs);
763	// An empty Result might mean a line with ';' or some parsing error, ignore
764	// it.
765	if (Result) {
766	if (ImportState == Sema::ModuleImportState::FirstDecl)
767	// First decl was not modular.
768	ImportState = Sema::ModuleImportState::NotACXX20Module;
769	else if (ImportState == Sema::ModuleImportState::ImportAllowed)
770	// Non-imports disallow further imports.
771	ImportState = Sema::ModuleImportState::ImportFinished;
772	else if (ImportState ==
773	Sema::ModuleImportState::PrivateFragmentImportAllowed)
774	// Non-imports disallow further imports.
775	ImportState = Sema::ModuleImportState::PrivateFragmentImportFinished;
776	}
777	return false;
778	}
779
780	/// ParseExternalDeclaration:
781	///
782	/// The `Attrs` that are passed in are C++11 attributes and appertain to the
783	/// declaration.
784	///
785	/// external-declaration: [C99 6.9], declaration: [C++ dcl.dcl]
786	/// function-definition
787	/// declaration
788	/// [GNU] asm-definition
789	/// [GNU] __extension__ external-declaration
790	/// [OBJC] objc-class-definition
791	/// [OBJC] objc-class-declaration
792	/// [OBJC] objc-alias-declaration
793	/// [OBJC] objc-protocol-definition
794	/// [OBJC] objc-method-definition
795	/// [OBJC] @end
796	/// [C++] linkage-specification
797	/// [GNU] asm-definition:
798	/// simple-asm-expr ';'
799	/// [C++11] empty-declaration
800	/// [C++11] attribute-declaration
801	///
802	/// [C++11] empty-declaration:
803	/// ';'
804	///
805	/// [C++0x/GNU] 'extern' 'template' declaration
806	///
807	/// [C++20] module-import-declaration
808	///
809	Parser::DeclGroupPtrTy
810	Parser::ParseExternalDeclaration(ParsedAttributes &Attrs,
811	ParsedAttributes &DeclSpecAttrs,
812	ParsingDeclSpec *DS) {
813	DestroyTemplateIdAnnotationsRAIIObj CleanupRAII(*this);
814	ParenBraceBracketBalancer BalancerRAIIObj(*this);
815
816	if (PP.isCodeCompletionReached()) {
817	cutOffParsing();
818	return nullptr;
819	}
820
821	Decl *SingleDecl = nullptr;
822	switch (Tok.getKind()) {
823	case tok::annot_pragma_vis:
824	HandlePragmaVisibility();
825	return nullptr;
826	case tok::annot_pragma_pack:
827	HandlePragmaPack();
828	return nullptr;
829	case tok::annot_pragma_msstruct:
830	HandlePragmaMSStruct();
831	return nullptr;
832	case tok::annot_pragma_align:
833	HandlePragmaAlign();
834	return nullptr;
835	case tok::annot_pragma_weak:
836	HandlePragmaWeak();
837	return nullptr;
838	case tok::annot_pragma_weakalias:
839	HandlePragmaWeakAlias();
840	return nullptr;
841	case tok::annot_pragma_redefine_extname:
842	HandlePragmaRedefineExtname();
843	return nullptr;
844	case tok::annot_pragma_fp_contract:
845	HandlePragmaFPContract();
846	return nullptr;
847	case tok::annot_pragma_fenv_access:
848	case tok::annot_pragma_fenv_access_ms:
849	HandlePragmaFEnvAccess();
850	return nullptr;
851	case tok::annot_pragma_fenv_round:
852	HandlePragmaFEnvRound();
853	return nullptr;
854	case tok::annot_pragma_cx_limited_range:
855	HandlePragmaCXLimitedRange();
856	return nullptr;
857	case tok::annot_pragma_float_control:
858	HandlePragmaFloatControl();
859	return nullptr;
860	case tok::annot_pragma_fp:
861	HandlePragmaFP();
862	break;
863	case tok::annot_pragma_opencl_extension:
864	HandlePragmaOpenCLExtension();
865	return nullptr;
866	case tok::annot_attr_openmp:
867	case tok::annot_pragma_openmp: {
868	AccessSpecifier AS = AS_none;
869	return ParseOpenMPDeclarativeDirectiveWithExtDecl(AS, Attrs);
870	}
871	case tok::annot_pragma_openacc:
872	return ParseOpenACCDirectiveDecl();
873	case tok::annot_pragma_ms_pointers_to_members:
874	HandlePragmaMSPointersToMembers();
875	return nullptr;
876	case tok::annot_pragma_ms_vtordisp:
877	HandlePragmaMSVtorDisp();
878	return nullptr;
879	case tok::annot_pragma_ms_pragma:
880	HandlePragmaMSPragma();
881	return nullptr;
882	case tok::annot_pragma_dump:
883	HandlePragmaDump();
884	return nullptr;
885	case tok::annot_pragma_attribute:
886	HandlePragmaAttribute();
887	return nullptr;
888	case tok::semi:
889	// Either a C++11 empty-declaration or attribute-declaration.
890	SingleDecl =
891	Actions.ActOnEmptyDeclaration(S: getCurScope(), AttrList: Attrs, SemiLoc: Tok.getLocation());
892	ConsumeExtraSemi(Kind: OutsideFunction);
893	break;
894	case tok::r_brace:
895	Diag(Tok, diag::err_extraneous_closing_brace);
896	ConsumeBrace();
897	return nullptr;
898	case tok::eof:
899	Diag(Tok, diag::err_expected_external_declaration);
900	return nullptr;
901	case tok::kw___extension__: {
902	// __extension__ silences extension warnings in the subexpression.
903	ExtensionRAIIObject O(Diags); // Use RAII to do this.
904	ConsumeToken();
905	return ParseExternalDeclaration(Attrs, DeclSpecAttrs);
906	}
907	case tok::kw_asm: {
908	ProhibitAttributes(Attrs);
909
910	SourceLocation StartLoc = Tok.getLocation();
911	SourceLocation EndLoc;
912
913	ExprResult Result(ParseSimpleAsm(/*ForAsmLabel*/ false, EndLoc: &EndLoc));
914
915	// Check if GNU-style InlineAsm is disabled.
916	// Empty asm string is allowed because it will not introduce
917	// any assembly code.
918	if (!(getLangOpts().GNUAsm || Result.isInvalid())) {
919	const auto *SL = cast<StringLiteral>(Val: Result.get());
920	if (!SL->getString().trim().empty())
921	Diag(StartLoc, diag::err_gnu_inline_asm_disabled);
922	}
923
924	ExpectAndConsume(tok::semi, diag::err_expected_after,
925	"top-level asm block");
926
927	if (Result.isInvalid())
928	return nullptr;
929	SingleDecl = Actions.ActOnFileScopeAsmDecl(expr: Result.get(), AsmLoc: StartLoc, RParenLoc: EndLoc);
930	break;
931	}
932	case tok::at:
933	return ParseObjCAtDirectives(DeclAttrs&: Attrs, DeclSpecAttrs);
934	case tok::minus:
935	case tok::plus:
936	if (!getLangOpts().ObjC) {
937	Diag(Tok, diag::err_expected_external_declaration);
938	ConsumeToken();
939	return nullptr;
940	}
941	SingleDecl = ParseObjCMethodDefinition();
942	break;
943	case tok::code_completion:
944	cutOffParsing();
945	if (CurParsedObjCImpl) {
946	// Code-complete Objective-C methods even without leading '-'/'+' prefix.
947	Actions.CodeCompleteObjCMethodDecl(S: getCurScope(),
948	/*IsInstanceMethod=*/std::nullopt,
949	/*ReturnType=*/nullptr);
950	}
951
952	Sema::ParserCompletionContext PCC;
953	if (CurParsedObjCImpl) {
954	PCC = Sema::PCC_ObjCImplementation;
955	} else if (PP.isIncrementalProcessingEnabled()) {
956	PCC = Sema::PCC_TopLevelOrExpression;
957	} else {
958	PCC = Sema::PCC_Namespace;
959	};
960	Actions.CodeCompleteOrdinaryName(S: getCurScope(), CompletionContext: PCC);
961	return nullptr;
962	case tok::kw_import: {
963	Sema::ModuleImportState IS = Sema::ModuleImportState::NotACXX20Module;
964	if (getLangOpts().CPlusPlusModules) {
965	llvm_unreachable("not expecting a c++20 import here");
966	ProhibitAttributes(Attrs);
967	}
968	SingleDecl = ParseModuleImport(AtLoc: SourceLocation(), ImportState&: IS);
969	} break;
970	case tok::kw_export:
971	if (getLangOpts().CPlusPlusModules) {
972	ProhibitAttributes(Attrs);
973	SingleDecl = ParseExportDeclaration();
974	break;
975	}
976	// This must be 'export template'. Parse it so we can diagnose our lack
977	// of support.
978	[[fallthrough]];
979	case tok::kw_using:
980	case tok::kw_namespace:
981	case tok::kw_typedef:
982	case tok::kw_template:
983	case tok::kw_static_assert:
984	case tok::kw__Static_assert:
985	// A function definition cannot start with any of these keywords.
986	{
987	SourceLocation DeclEnd;
988	return ParseDeclaration(Context: DeclaratorContext::File, DeclEnd, DeclAttrs&: Attrs,
989	DeclSpecAttrs);
990	}
991
992	case tok::kw_cbuffer:
993	case tok::kw_tbuffer:
994	if (getLangOpts().HLSL) {
995	SourceLocation DeclEnd;
996	return ParseDeclaration(Context: DeclaratorContext::File, DeclEnd, DeclAttrs&: Attrs,
997	DeclSpecAttrs);
998	}
999	goto dont_know;
1000
1001	case tok::kw_static:
1002	// Parse (then ignore) 'static' prior to a template instantiation. This is
1003	// a GCC extension that we intentionally do not support.
1004	if (getLangOpts().CPlusPlus && NextToken().is(K: tok::kw_template)) {
1005	Diag(ConsumeToken(), diag::warn_static_inline_explicit_inst_ignored)
1006	<< 0;
1007	SourceLocation DeclEnd;
1008	return ParseDeclaration(Context: DeclaratorContext::File, DeclEnd, DeclAttrs&: Attrs,
1009	DeclSpecAttrs);
1010	}
1011	goto dont_know;
1012
1013	case tok::kw_inline:
1014	if (getLangOpts().CPlusPlus) {
1015	tok::TokenKind NextKind = NextToken().getKind();
1016
1017	// Inline namespaces. Allowed as an extension even in C++03.
1018	if (NextKind == tok::kw_namespace) {
1019	SourceLocation DeclEnd;
1020	return ParseDeclaration(Context: DeclaratorContext::File, DeclEnd, DeclAttrs&: Attrs,
1021	DeclSpecAttrs);
1022	}
1023
1024	// Parse (then ignore) 'inline' prior to a template instantiation. This is
1025	// a GCC extension that we intentionally do not support.
1026	if (NextKind == tok::kw_template) {
1027	Diag(ConsumeToken(), diag::warn_static_inline_explicit_inst_ignored)
1028	<< 1;
1029	SourceLocation DeclEnd;
1030	return ParseDeclaration(Context: DeclaratorContext::File, DeclEnd, DeclAttrs&: Attrs,
1031	DeclSpecAttrs);
1032	}
1033	}
1034	goto dont_know;
1035
1036	case tok::kw_extern:
1037	if (getLangOpts().CPlusPlus && NextToken().is(K: tok::kw_template)) {
1038	// Extern templates
1039	SourceLocation ExternLoc = ConsumeToken();
1040	SourceLocation TemplateLoc = ConsumeToken();
1041	Diag(ExternLoc, getLangOpts().CPlusPlus11 ?
1042	diag::warn_cxx98_compat_extern_template :
1043	diag::ext_extern_template) << SourceRange(ExternLoc, TemplateLoc);
1044	SourceLocation DeclEnd;
1045	return ParseExplicitInstantiation(Context: DeclaratorContext::File, ExternLoc,
1046	TemplateLoc, DeclEnd, AccessAttrs&: Attrs);
1047	}
1048	goto dont_know;
1049
1050	case tok::kw___if_exists:
1051	case tok::kw___if_not_exists:
1052	ParseMicrosoftIfExistsExternalDeclaration();
1053	return nullptr;
1054
1055	case tok::kw_module:
1056	Diag(Tok, diag::err_unexpected_module_decl);
1057	SkipUntil(T: tok::semi);
1058	return nullptr;
1059
1060	default:
1061	dont_know:
1062	if (Tok.isEditorPlaceholder()) {
1063	ConsumeToken();
1064	return nullptr;
1065	}
1066	if (getLangOpts().IncrementalExtensions &&
1067	!isDeclarationStatement(/*DisambiguatingWithExpression=*/true))
1068	return ParseTopLevelStmtDecl();
1069
1070	// We can't tell whether this is a function-definition or declaration yet.
1071	if (!SingleDecl)
1072	return ParseDeclarationOrFunctionDefinition(DeclAttrs&: Attrs, DeclSpecAttrs, DS);
1073	}
1074
1075	// This routine returns a DeclGroup, if the thing we parsed only contains a
1076	// single decl, convert it now.
1077	return Actions.ConvertDeclToDeclGroup(Ptr: SingleDecl);
1078	}
1079
1080	/// Determine whether the current token, if it occurs after a
1081	/// declarator, continues a declaration or declaration list.
1082	bool Parser::isDeclarationAfterDeclarator() {
1083	// Check for '= delete' or '= default'
1084	if (getLangOpts().CPlusPlus && Tok.is(K: tok::equal)) {
1085	const Token &KW = NextToken();
1086	if (KW.is(K: tok::kw_default) || KW.is(K: tok::kw_delete))
1087	return false;
1088	}
1089
1090	return Tok.is(K: tok::equal) || // int X()= -> not a function def
1091	Tok.is(K: tok::comma) || // int X(), -> not a function def
1092	Tok.is(K: tok::semi) || // int X(); -> not a function def
1093	Tok.is(K: tok::kw_asm) || // int X() __asm__ -> not a function def
1094	Tok.is(K: tok::kw___attribute) || // int X() __attr__ -> not a function def
1095	(getLangOpts().CPlusPlus &&
1096	Tok.is(K: tok::l_paren)); // int X(0) -> not a function def [C++]
1097	}
1098
1099	/// Determine whether the current token, if it occurs after a
1100	/// declarator, indicates the start of a function definition.
1101	bool Parser::isStartOfFunctionDefinition(const ParsingDeclarator &Declarator) {
1102	assert(Declarator.isFunctionDeclarator() && "Isn't a function declarator");
1103	if (Tok.is(K: tok::l_brace)) // int X() {}
1104	return true;
1105
1106	// Handle K&R C argument lists: int X(f) int f; {}
1107	if (!getLangOpts().CPlusPlus &&
1108	Declarator.getFunctionTypeInfo().isKNRPrototype())
1109	return isDeclarationSpecifier(AllowImplicitTypename: ImplicitTypenameContext::No);
1110
1111	if (getLangOpts().CPlusPlus && Tok.is(K: tok::equal)) {
1112	const Token &KW = NextToken();
1113	return KW.is(K: tok::kw_default) || KW.is(K: tok::kw_delete);
1114	}
1115
1116	return Tok.is(K: tok::colon) || // X() : Base() {} (used for ctors)
1117	Tok.is(K: tok::kw_try); // X() try { ... }
1118	}
1119
1120	/// Parse either a function-definition or a declaration. We can't tell which
1121	/// we have until we read up to the compound-statement in function-definition.
1122	/// TemplateParams, if non-NULL, provides the template parameters when we're
1123	/// parsing a C++ template-declaration.
1124	///
1125	/// function-definition: [C99 6.9.1]
1126	/// decl-specs declarator declaration-list[opt] compound-statement
1127	/// [C90] function-definition: [C99 6.7.1] - implicit int result
1128	/// [C90] decl-specs[opt] declarator declaration-list[opt] compound-statement
1129	///
1130	/// declaration: [C99 6.7]
1131	/// declaration-specifiers init-declarator-list[opt] ';'
1132	/// [!C99] init-declarator-list ';' [TODO: warn in c99 mode]
1133	/// [OMP] threadprivate-directive
1134	/// [OMP] allocate-directive [TODO]
1135	///
1136	Parser::DeclGroupPtrTy Parser::ParseDeclOrFunctionDefInternal(
1137	ParsedAttributes &Attrs, ParsedAttributes &DeclSpecAttrs,
1138	ParsingDeclSpec &DS, AccessSpecifier AS) {
1139	// Because we assume that the DeclSpec has not yet been initialised, we simply
1140	// overwrite the source range and attribute the provided leading declspec
1141	// attributes.
1142	assert(DS.getSourceRange().isInvalid() &&
1143	"expected uninitialised source range");
1144	DS.SetRangeStart(DeclSpecAttrs.Range.getBegin());
1145	DS.SetRangeEnd(DeclSpecAttrs.Range.getEnd());
1146	DS.takeAttributesFrom(attrs&: DeclSpecAttrs);
1147
1148	ParsedTemplateInfo TemplateInfo;
1149	MaybeParseMicrosoftAttributes(Attrs&: DS.getAttributes());
1150	// Parse the common declaration-specifiers piece.
1151	ParseDeclarationSpecifiers(DS, TemplateInfo, AS,
1152	DSC: DeclSpecContext::DSC_top_level);
1153
1154	// If we had a free-standing type definition with a missing semicolon, we
1155	// may get this far before the problem becomes obvious.
1156	if (DS.hasTagDefinition() && DiagnoseMissingSemiAfterTagDefinition(
1157	DS, AS, DSContext: DeclSpecContext::DSC_top_level))
1158	return nullptr;
1159
1160	// C99 6.7.2.3p6: Handle "struct-or-union identifier;", "enum { X };"
1161	// declaration-specifiers init-declarator-list[opt] ';'
1162	if (Tok.is(K: tok::semi)) {
1163	auto LengthOfTSTToken = [](DeclSpec::TST TKind) {
1164	assert(DeclSpec::isDeclRep(TKind));
1165	switch(TKind) {
1166	case DeclSpec::TST_class:
1167	return 5;
1168	case DeclSpec::TST_struct:
1169	return 6;
1170	case DeclSpec::TST_union:
1171	return 5;
1172	case DeclSpec::TST_enum:
1173	return 4;
1174	case DeclSpec::TST_interface:
1175	return 9;
1176	default:
1177	llvm_unreachable("we only expect to get the length of the class/struct/union/enum");
1178	}
1179
1180	};
1181	// Suggest correct location to fix '[[attrib]] struct' to 'struct [[attrib]]'
1182	SourceLocation CorrectLocationForAttributes =
1183	DeclSpec::isDeclRep(T: DS.getTypeSpecType())
1184	? DS.getTypeSpecTypeLoc().getLocWithOffset(
1185	Offset: LengthOfTSTToken(DS.getTypeSpecType()))
1186	: SourceLocation();
1187	ProhibitAttributes(Attrs, FixItLoc: CorrectLocationForAttributes);
1188	ConsumeToken();
1189	RecordDecl *AnonRecord = nullptr;
1190	Decl *TheDecl = Actions.ParsedFreeStandingDeclSpec(
1191	S: getCurScope(), AS: AS_none, DS, DeclAttrs: ParsedAttributesView::none(), AnonRecord);
1192	DS.complete(D: TheDecl);
1193	Actions.ActOnDefinedDeclarationSpecifier(D: TheDecl);
1194	if (AnonRecord) {
1195	Decl* decls[] = {AnonRecord, TheDecl};
1196	return Actions.BuildDeclaratorGroup(decls);
1197	}
1198	return Actions.ConvertDeclToDeclGroup(Ptr: TheDecl);
1199	}
1200
1201	if (DS.hasTagDefinition())
1202	Actions.ActOnDefinedDeclarationSpecifier(D: DS.getRepAsDecl());
1203
1204	// ObjC2 allows prefix attributes on class interfaces and protocols.
1205	// FIXME: This still needs better diagnostics. We should only accept
1206	// attributes here, no types, etc.
1207	if (getLangOpts().ObjC && Tok.is(K: tok::at)) {
1208	SourceLocation AtLoc = ConsumeToken(); // the "@"
1209	if (!Tok.isObjCAtKeyword(objcKey: tok::objc_interface) &&
1210	!Tok.isObjCAtKeyword(objcKey: tok::objc_protocol) &&
1211	!Tok.isObjCAtKeyword(objcKey: tok::objc_implementation)) {
1212	Diag(Tok, diag::err_objc_unexpected_attr);
1213	SkipUntil(T: tok::semi);
1214	return nullptr;
1215	}
1216
1217	DS.abort();
1218	DS.takeAttributesFrom(attrs&: Attrs);
1219
1220	const char *PrevSpec = nullptr;
1221	unsigned DiagID;
1222	if (DS.SetTypeSpecType(T: DeclSpec::TST_unspecified, Loc: AtLoc, PrevSpec, DiagID,
1223	Policy: Actions.getASTContext().getPrintingPolicy()))
1224	Diag(Loc: AtLoc, DiagID) << PrevSpec;
1225
1226	if (Tok.isObjCAtKeyword(objcKey: tok::objc_protocol))
1227	return ParseObjCAtProtocolDeclaration(atLoc: AtLoc, prefixAttrs&: DS.getAttributes());
1228
1229	if (Tok.isObjCAtKeyword(objcKey: tok::objc_implementation))
1230	return ParseObjCAtImplementationDeclaration(AtLoc, Attrs&: DS.getAttributes());
1231
1232	return Actions.ConvertDeclToDeclGroup(
1233	Ptr: ParseObjCAtInterfaceDeclaration(AtLoc, prefixAttrs&: DS.getAttributes()));
1234	}
1235
1236	// If the declspec consisted only of 'extern' and we have a string
1237	// literal following it, this must be a C++ linkage specifier like
1238	// 'extern "C"'.
1239	if (getLangOpts().CPlusPlus && isTokenStringLiteral() &&
1240	DS.getStorageClassSpec() == DeclSpec::SCS_extern &&
1241	DS.getParsedSpecifiers() == DeclSpec::PQ_StorageClassSpecifier) {
1242	ProhibitAttributes(Attrs);
1243	Decl *TheDecl = ParseLinkage(DS, Context: DeclaratorContext::File);
1244	return Actions.ConvertDeclToDeclGroup(Ptr: TheDecl);
1245	}
1246
1247	return ParseDeclGroup(DS, Context: DeclaratorContext::File, Attrs, TemplateInfo);
1248	}
1249
1250	Parser::DeclGroupPtrTy Parser::ParseDeclarationOrFunctionDefinition(
1251	ParsedAttributes &Attrs, ParsedAttributes &DeclSpecAttrs,
1252	ParsingDeclSpec *DS, AccessSpecifier AS) {
1253	// Add an enclosing time trace scope for a bunch of small scopes with
1254	// "EvaluateAsConstExpr".
1255	llvm::TimeTraceScope TimeScope("ParseDeclarationOrFunctionDefinition", [&]() {
1256	return Tok.getLocation().printToString(
1257	SM: Actions.getASTContext().getSourceManager());
1258	});
1259
1260	if (DS) {
1261	return ParseDeclOrFunctionDefInternal(Attrs, DeclSpecAttrs, DS&: *DS, AS);
1262	} else {
1263	ParsingDeclSpec PDS(*this);
1264	// Must temporarily exit the objective-c container scope for
1265	// parsing c constructs and re-enter objc container scope
1266	// afterwards.
1267	ObjCDeclContextSwitch ObjCDC(*this);
1268
1269	return ParseDeclOrFunctionDefInternal(Attrs, DeclSpecAttrs, DS&: PDS, AS);
1270	}
1271	}
1272
1273	/// ParseFunctionDefinition - We parsed and verified that the specified
1274	/// Declarator is well formed. If this is a K&R-style function, read the
1275	/// parameters declaration-list, then start the compound-statement.
1276	///
1277	/// function-definition: [C99 6.9.1]
1278	/// decl-specs declarator declaration-list[opt] compound-statement
1279	/// [C90] function-definition: [C99 6.7.1] - implicit int result
1280	/// [C90] decl-specs[opt] declarator declaration-list[opt] compound-statement
1281	/// [C++] function-definition: [C++ 8.4]
1282	/// decl-specifier-seq[opt] declarator ctor-initializer[opt]
1283	/// function-body
1284	/// [C++] function-definition: [C++ 8.4]
1285	/// decl-specifier-seq[opt] declarator function-try-block
1286	///
1287	Decl *Parser::ParseFunctionDefinition(ParsingDeclarator &D,
1288	const ParsedTemplateInfo &TemplateInfo,
1289	LateParsedAttrList *LateParsedAttrs) {
1290	llvm::TimeTraceScope TimeScope("ParseFunctionDefinition", [&]() {
1291	return Actions.GetNameForDeclarator(D).getName().getAsString();
1292	});
1293
1294	// Poison SEH identifiers so they are flagged as illegal in function bodies.
1295	PoisonSEHIdentifiersRAIIObject PoisonSEHIdentifiers(*this, true);
1296	const DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
1297	TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
1298
1299	// If this is C89 and the declspecs were completely missing, fudge in an
1300	// implicit int. We do this here because this is the only place where
1301	// declaration-specifiers are completely optional in the grammar.
1302	if (getLangOpts().isImplicitIntRequired() && D.getDeclSpec().isEmpty()) {
1303	Diag(D.getIdentifierLoc(), diag::warn_missing_type_specifier)
1304	<< D.getDeclSpec().getSourceRange();
1305	const char *PrevSpec;
1306	unsigned DiagID;
1307	const PrintingPolicy &Policy = Actions.getASTContext().getPrintingPolicy();
1308	D.getMutableDeclSpec().SetTypeSpecType(T: DeclSpec::TST_int,
1309	Loc: D.getIdentifierLoc(),
1310	PrevSpec, DiagID,
1311	Policy);
1312	D.SetRangeBegin(D.getDeclSpec().getSourceRange().getBegin());
1313	}
1314
1315	// If this declaration was formed with a K&R-style identifier list for the
1316	// arguments, parse declarations for all of the args next.
1317	// int foo(a,b) int a; float b; {}
1318	if (FTI.isKNRPrototype())
1319	ParseKNRParamDeclarations(D);
1320
1321	// We should have either an opening brace or, in a C++ constructor,
1322	// we may have a colon.
1323	if (Tok.isNot(K: tok::l_brace) &&
1324	(!getLangOpts().CPlusPlus ||
1325	(Tok.isNot(K: tok::colon) && Tok.isNot(K: tok::kw_try) &&
1326	Tok.isNot(K: tok::equal)))) {
1327	Diag(Tok, diag::err_expected_fn_body);
1328
1329	// Skip over garbage, until we get to '{'. Don't eat the '{'.
1330	SkipUntil(T: tok::l_brace, Flags: StopAtSemi | StopBeforeMatch);
1331
1332	// If we didn't find the '{', bail out.
1333	if (Tok.isNot(K: tok::l_brace))
1334	return nullptr;
1335	}
1336
1337	// Check to make sure that any normal attributes are allowed to be on
1338	// a definition. Late parsed attributes are checked at the end.
1339	if (Tok.isNot(K: tok::equal)) {
1340	for (const ParsedAttr &AL : D.getAttributes())
1341	if (AL.isKnownToGCC() && !AL.isStandardAttributeSyntax())
1342	Diag(AL.getLoc(), diag::warn_attribute_on_function_definition) << AL;
1343	}
1344
1345	// In delayed template parsing mode, for function template we consume the
1346	// tokens and store them for late parsing at the end of the translation unit.
1347	if (getLangOpts().DelayedTemplateParsing && Tok.isNot(K: tok::equal) &&
1348	TemplateInfo.Kind == ParsedTemplateInfo::Template &&
1349	Actions.canDelayFunctionBody(D)) {
1350	MultiTemplateParamsArg TemplateParameterLists(*TemplateInfo.TemplateParams);
1351
1352	ParseScope BodyScope(this, Scope::FnScope | Scope::DeclScope |
1353	Scope::CompoundStmtScope);
1354	Scope *ParentScope = getCurScope()->getParent();
1355
1356	D.setFunctionDefinitionKind(FunctionDefinitionKind::Definition);
1357	Decl *DP = Actions.HandleDeclarator(S: ParentScope, D,
1358	TemplateParameterLists);
1359	D.complete(D: DP);
1360	D.getMutableDeclSpec().abort();
1361
1362	if (SkipFunctionBodies && (!DP || Actions.canSkipFunctionBody(D: DP)) &&
1363	trySkippingFunctionBody()) {
1364	BodyScope.Exit();
1365	return Actions.ActOnSkippedFunctionBody(Decl: DP);
1366	}
1367
1368	CachedTokens Toks;
1369	LexTemplateFunctionForLateParsing(Toks);
1370
1371	if (DP) {
1372	FunctionDecl *FnD = DP->getAsFunction();
1373	Actions.CheckForFunctionRedefinition(FD: FnD);
1374	Actions.MarkAsLateParsedTemplate(FD: FnD, FnD: DP, Toks);
1375	}
1376	return DP;
1377	}
1378	else if (CurParsedObjCImpl &&
1379	!TemplateInfo.TemplateParams &&
1380	(Tok.is(K: tok::l_brace) || Tok.is(K: tok::kw_try) ||
1381	Tok.is(K: tok::colon)) &&
1382	Actions.CurContext->isTranslationUnit()) {
1383	ParseScope BodyScope(this, Scope::FnScope | Scope::DeclScope |
1384	Scope::CompoundStmtScope);
1385	Scope *ParentScope = getCurScope()->getParent();
1386
1387	D.setFunctionDefinitionKind(FunctionDefinitionKind::Definition);
1388	Decl *FuncDecl = Actions.HandleDeclarator(S: ParentScope, D,
1389	TemplateParameterLists: MultiTemplateParamsArg());
1390	D.complete(D: FuncDecl);
1391	D.getMutableDeclSpec().abort();
1392	if (FuncDecl) {
1393	// Consume the tokens and store them for later parsing.
1394	StashAwayMethodOrFunctionBodyTokens(MDecl: FuncDecl);
1395	CurParsedObjCImpl->HasCFunction = true;
1396	return FuncDecl;
1397	}
1398	// FIXME: Should we really fall through here?
1399	}
1400
1401	// Enter a scope for the function body.
1402	ParseScope BodyScope(this, Scope::FnScope | Scope::DeclScope |
1403	Scope::CompoundStmtScope);
1404
1405	// Parse function body eagerly if it is either '= delete;' or '= default;' as
1406	// ActOnStartOfFunctionDef needs to know whether the function is deleted.
1407	StringLiteral *DeletedMessage = nullptr;
1408	Sema::FnBodyKind BodyKind = Sema::FnBodyKind::Other;
1409	SourceLocation KWLoc;
1410	if (TryConsumeToken(Expected: tok::equal)) {
1411	assert(getLangOpts().CPlusPlus && "Only C++ function definitions have '='");
1412
1413	if (TryConsumeToken(Expected: tok::kw_delete, Loc&: KWLoc)) {
1414	Diag(KWLoc, getLangOpts().CPlusPlus11
1415	? diag::warn_cxx98_compat_defaulted_deleted_function
1416	: diag::ext_defaulted_deleted_function)
1417	<< 1 /* deleted */;
1418	BodyKind = Sema::FnBodyKind::Delete;
1419	DeletedMessage = ParseCXXDeletedFunctionMessage();
1420	} else if (TryConsumeToken(Expected: tok::kw_default, Loc&: KWLoc)) {
1421	Diag(KWLoc, getLangOpts().CPlusPlus11
1422	? diag::warn_cxx98_compat_defaulted_deleted_function
1423	: diag::ext_defaulted_deleted_function)
1424	<< 0 /* defaulted */;
1425	BodyKind = Sema::FnBodyKind::Default;
1426	} else {
1427	llvm_unreachable("function definition after = not 'delete' or 'default'");
1428	}
1429
1430	if (Tok.is(K: tok::comma)) {
1431	Diag(KWLoc, diag::err_default_delete_in_multiple_declaration)
1432	<< (BodyKind == Sema::FnBodyKind::Delete);
1433	SkipUntil(T: tok::semi);
1434	} else if (ExpectAndConsume(tok::semi, diag::err_expected_after,
1435	BodyKind == Sema::FnBodyKind::Delete
1436	? "delete"
1437	: "default")) {
1438	SkipUntil(T: tok::semi);
1439	}
1440	}
1441
1442	// Tell the actions module that we have entered a function definition with the
1443	// specified Declarator for the function.
1444	SkipBodyInfo SkipBody;
1445	Decl *Res = Actions.ActOnStartOfFunctionDef(S: getCurScope(), D,
1446	TemplateParamLists: TemplateInfo.TemplateParams
1447	? *TemplateInfo.TemplateParams
1448	: MultiTemplateParamsArg(),
1449	SkipBody: &SkipBody, BodyKind);
1450
1451	if (SkipBody.ShouldSkip) {
1452	// Do NOT enter SkipFunctionBody if we already consumed the tokens.
1453	if (BodyKind == Sema::FnBodyKind::Other)
1454	SkipFunctionBody();
1455
1456	// ExpressionEvaluationContext is pushed in ActOnStartOfFunctionDef
1457	// and it would be popped in ActOnFinishFunctionBody.
1458	// We pop it explcitly here since ActOnFinishFunctionBody won't get called.
1459	//
1460	// Do not call PopExpressionEvaluationContext() if it is a lambda because
1461	// one is already popped when finishing the lambda in BuildLambdaExpr().
1462	//
1463	// FIXME: It looks not easy to balance PushExpressionEvaluationContext()
1464	// and PopExpressionEvaluationContext().
1465	if (!isLambdaCallOperator(dyn_cast_if_present<FunctionDecl>(Val: Res)))
1466	Actions.PopExpressionEvaluationContext();
1467	return Res;
1468	}
1469
1470	// Break out of the ParsingDeclarator context before we parse the body.
1471	D.complete(D: Res);
1472
1473	// Break out of the ParsingDeclSpec context, too. This const_cast is
1474	// safe because we're always the sole owner.
1475	D.getMutableDeclSpec().abort();
1476
1477	if (BodyKind != Sema::FnBodyKind::Other) {
1478	Actions.SetFunctionBodyKind(D: Res, Loc: KWLoc, BodyKind, DeletedMessage);
1479	Stmt *GeneratedBody = Res ? Res->getBody() : nullptr;
1480	Actions.ActOnFinishFunctionBody(Decl: Res, Body: GeneratedBody, IsInstantiation: false);
1481	return Res;
1482	}
1483
1484	// With abbreviated function templates - we need to explicitly add depth to
1485	// account for the implicit template parameter list induced by the template.
1486	if (const auto *Template = dyn_cast_if_present<FunctionTemplateDecl>(Val: Res);
1487	Template && Template->isAbbreviated() &&
1488	Template->getTemplateParameters()->getParam(0)->isImplicit())
1489	// First template parameter is implicit - meaning no explicit template
1490	// parameter list was specified.
1491	CurTemplateDepthTracker.addDepth(D: 1);
1492
1493	if (SkipFunctionBodies && (!Res || Actions.canSkipFunctionBody(D: Res)) &&
1494	trySkippingFunctionBody()) {
1495	BodyScope.Exit();
1496	Actions.ActOnSkippedFunctionBody(Decl: Res);
1497	return Actions.ActOnFinishFunctionBody(Decl: Res, Body: nullptr, IsInstantiation: false);
1498	}
1499
1500	Sema::FPFeaturesStateRAII SaveFPFeatures(Actions);
1501
1502	if (Tok.is(K: tok::kw_try))
1503	return ParseFunctionTryBlock(Decl: Res, BodyScope);
1504
1505	// If we have a colon, then we're probably parsing a C++
1506	// ctor-initializer.
1507	if (Tok.is(K: tok::colon)) {
1508	ParseConstructorInitializer(ConstructorDecl: Res);
1509
1510	// Recover from error.
1511	if (!Tok.is(K: tok::l_brace)) {
1512	BodyScope.Exit();
1513	Actions.ActOnFinishFunctionBody(Decl: Res, Body: nullptr);
1514	return Res;
1515	}
1516	} else
1517	Actions.ActOnDefaultCtorInitializers(CDtorDecl: Res);
1518
1519	// Late attributes are parsed in the same scope as the function body.
1520	if (LateParsedAttrs)
1521	ParseLexedAttributeList(LAs&: *LateParsedAttrs, D: Res, EnterScope: false, OnDefinition: true);
1522
1523	return ParseFunctionStatementBody(Decl: Res, BodyScope);
1524	}
1525
1526	void Parser::SkipFunctionBody() {
1527	if (Tok.is(K: tok::equal)) {
1528	SkipUntil(T: tok::semi);
1529	return;
1530	}
1531
1532	bool IsFunctionTryBlock = Tok.is(K: tok::kw_try);
1533	if (IsFunctionTryBlock)
1534	ConsumeToken();
1535
1536	CachedTokens Skipped;
1537	if (ConsumeAndStoreFunctionPrologue(Toks&: Skipped))
1538	SkipMalformedDecl();
1539	else {
1540	SkipUntil(T: tok::r_brace);
1541	while (IsFunctionTryBlock && Tok.is(K: tok::kw_catch)) {
1542	SkipUntil(T: tok::l_brace);
1543	SkipUntil(T: tok::r_brace);
1544	}
1545	}
1546	}
1547
1548	/// ParseKNRParamDeclarations - Parse 'declaration-list[opt]' which provides
1549	/// types for a function with a K&R-style identifier list for arguments.
1550	void Parser::ParseKNRParamDeclarations(Declarator &D) {
1551	// We know that the top-level of this declarator is a function.
1552	DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
1553
1554	// Enter function-declaration scope, limiting any declarators to the
1555	// function prototype scope, including parameter declarators.
1556	ParseScope PrototypeScope(this, Scope::FunctionPrototypeScope |
1557	Scope::FunctionDeclarationScope | Scope::DeclScope);
1558
1559	// Read all the argument declarations.
1560	while (isDeclarationSpecifier(AllowImplicitTypename: ImplicitTypenameContext::No)) {
1561	SourceLocation DSStart = Tok.getLocation();
1562
1563	// Parse the common declaration-specifiers piece.
1564	DeclSpec DS(AttrFactory);
1565	ParseDeclarationSpecifiers(DS);
1566
1567	// C99 6.9.1p6: 'each declaration in the declaration list shall have at
1568	// least one declarator'.
1569	// NOTE: GCC just makes this an ext-warn. It's not clear what it does with
1570	// the declarations though. It's trivial to ignore them, really hard to do
1571	// anything else with them.
1572	if (TryConsumeToken(Expected: tok::semi)) {
1573	Diag(DSStart, diag::err_declaration_does_not_declare_param);
1574	continue;
1575	}
1576
1577	// C99 6.9.1p6: Declarations shall contain no storage-class specifiers other
1578	// than register.
1579	if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified &&
1580	DS.getStorageClassSpec() != DeclSpec::SCS_register) {
1581	Diag(DS.getStorageClassSpecLoc(),
1582	diag::err_invalid_storage_class_in_func_decl);
1583	DS.ClearStorageClassSpecs();
1584	}
1585	if (DS.getThreadStorageClassSpec() != DeclSpec::TSCS_unspecified) {
1586	Diag(DS.getThreadStorageClassSpecLoc(),
1587	diag::err_invalid_storage_class_in_func_decl);
1588	DS.ClearStorageClassSpecs();
1589	}
1590
1591	// Parse the first declarator attached to this declspec.
1592	Declarator ParmDeclarator(DS, ParsedAttributesView::none(),
1593	DeclaratorContext::KNRTypeList);
1594	ParseDeclarator(D&: ParmDeclarator);
1595
1596	// Handle the full declarator list.
1597	while (true) {
1598	// If attributes are present, parse them.
1599	MaybeParseGNUAttributes(D&: ParmDeclarator);
1600
1601	// Ask the actions module to compute the type for this declarator.
1602	Decl *Param =
1603	Actions.ActOnParamDeclarator(S: getCurScope(), D&: ParmDeclarator);
1604
1605	if (Param &&
1606	// A missing identifier has already been diagnosed.
1607	ParmDeclarator.getIdentifier()) {
1608
1609	// Scan the argument list looking for the correct param to apply this
1610	// type.
1611	for (unsigned i = 0; ; ++i) {
1612	// C99 6.9.1p6: those declarators shall declare only identifiers from
1613	// the identifier list.
1614	if (i == FTI.NumParams) {
1615	Diag(ParmDeclarator.getIdentifierLoc(), diag::err_no_matching_param)
1616	<< ParmDeclarator.getIdentifier();
1617	break;
1618	}
1619
1620	if (FTI.Params[i].Ident == ParmDeclarator.getIdentifier()) {
1621	// Reject redefinitions of parameters.
1622	if (FTI.Params[i].Param) {
1623	Diag(ParmDeclarator.getIdentifierLoc(),
1624	diag::err_param_redefinition)
1625	<< ParmDeclarator.getIdentifier();
1626	} else {
1627	FTI.Params[i].Param = Param;
1628	}
1629	break;
1630	}
1631	}
1632	}
1633
1634	// If we don't have a comma, it is either the end of the list (a ';') or
1635	// an error, bail out.
1636	if (Tok.isNot(K: tok::comma))
1637	break;
1638
1639	ParmDeclarator.clear();
1640
1641	// Consume the comma.
1642	ParmDeclarator.setCommaLoc(ConsumeToken());
1643
1644	// Parse the next declarator.
1645	ParseDeclarator(D&: ParmDeclarator);
1646	}
1647
1648	// Consume ';' and continue parsing.
1649	if (!ExpectAndConsumeSemi(diag::err_expected_semi_declaration))
1650	continue;
1651
1652	// Otherwise recover by skipping to next semi or mandatory function body.
1653	if (SkipUntil(T: tok::l_brace, Flags: StopAtSemi | StopBeforeMatch))
1654	break;
1655	TryConsumeToken(Expected: tok::semi);
1656	}
1657
1658	// The actions module must verify that all arguments were declared.
1659	Actions.ActOnFinishKNRParamDeclarations(S: getCurScope(), D, LocAfterDecls: Tok.getLocation());
1660	}
1661
1662
1663	/// ParseAsmStringLiteral - This is just a normal string-literal, but is not
1664	/// allowed to be a wide string, and is not subject to character translation.
1665	/// Unlike GCC, we also diagnose an empty string literal when parsing for an
1666	/// asm label as opposed to an asm statement, because such a construct does not
1667	/// behave well.
1668	///
1669	/// [GNU] asm-string-literal:
1670	/// string-literal
1671	///
1672	ExprResult Parser::ParseAsmStringLiteral(bool ForAsmLabel) {
1673	if (!isTokenStringLiteral()) {
1674	Diag(Tok, diag::err_expected_string_literal)
1675	<< /*Source='in...'*/0 << "'asm'";
1676	return ExprError();
1677	}
1678
1679	ExprResult AsmString(ParseStringLiteralExpression());
1680	if (!AsmString.isInvalid()) {
1681	const auto *SL = cast<StringLiteral>(Val: AsmString.get());
1682	if (!SL->isOrdinary()) {
1683	Diag(Tok, diag::err_asm_operand_wide_string_literal)
1684	<< SL->isWide()
1685	<< SL->getSourceRange();
1686	return ExprError();
1687	}
1688	if (ForAsmLabel && SL->getString().empty()) {
1689	Diag(Tok, diag::err_asm_operand_wide_string_literal)
1690	<< 2 /* an empty */ << SL->getSourceRange();
1691	return ExprError();
1692	}
1693	}
1694	return AsmString;
1695	}
1696
1697	/// ParseSimpleAsm
1698	///
1699	/// [GNU] simple-asm-expr:
1700	/// 'asm' '(' asm-string-literal ')'
1701	///
1702	ExprResult Parser::ParseSimpleAsm(bool ForAsmLabel, SourceLocation *EndLoc) {
1703	assert(Tok.is(tok::kw_asm) && "Not an asm!");
1704	SourceLocation Loc = ConsumeToken();
1705
1706	if (isGNUAsmQualifier(TokAfterAsm: Tok)) {
1707	// Remove from the end of 'asm' to the end of the asm qualifier.
1708	SourceRange RemovalRange(PP.getLocForEndOfToken(Loc),
1709	PP.getLocForEndOfToken(Loc: Tok.getLocation()));
1710	Diag(Tok, diag::err_global_asm_qualifier_ignored)
1711	<< GNUAsmQualifiers::getQualifierName(getGNUAsmQualifier(Tok))
1712	<< FixItHint::CreateRemoval(RemovalRange);
1713	ConsumeToken();
1714	}
1715
1716	BalancedDelimiterTracker T(*this, tok::l_paren);
1717	if (T.consumeOpen()) {
1718	Diag(Tok, diag::err_expected_lparen_after) << "asm";
1719	return ExprError();
1720	}
1721
1722	ExprResult Result(ParseAsmStringLiteral(ForAsmLabel));
1723
1724	if (!Result.isInvalid()) {
1725	// Close the paren and get the location of the end bracket
1726	T.consumeClose();
1727	if (EndLoc)
1728	*EndLoc = T.getCloseLocation();
1729	} else if (SkipUntil(T: tok::r_paren, Flags: StopAtSemi | StopBeforeMatch)) {
1730	if (EndLoc)
1731	*EndLoc = Tok.getLocation();
1732	ConsumeParen();
1733	}
1734
1735	return Result;
1736	}
1737
1738	/// Get the TemplateIdAnnotation from the token and put it in the
1739	/// cleanup pool so that it gets destroyed when parsing the current top level
1740	/// declaration is finished.
1741	TemplateIdAnnotation *Parser::takeTemplateIdAnnotation(const Token &tok) {
1742	assert(tok.is(tok::annot_template_id) && "Expected template-id token");
1743	TemplateIdAnnotation *
1744	Id = static_cast<TemplateIdAnnotation *>(tok.getAnnotationValue());
1745	return Id;
1746	}
1747
1748	void Parser::AnnotateScopeToken(CXXScopeSpec &SS, bool IsNewAnnotation) {
1749	// Push the current token back into the token stream (or revert it if it is
1750	// cached) and use an annotation scope token for current token.
1751	if (PP.isBacktrackEnabled())
1752	PP.RevertCachedTokens(N: 1);
1753	else
1754	PP.EnterToken(Tok, /*IsReinject=*/true);
1755	Tok.setKind(tok::annot_cxxscope);
1756	Tok.setAnnotationValue(Actions.SaveNestedNameSpecifierAnnotation(SS));
1757	Tok.setAnnotationRange(SS.getRange());
1758
1759	// In case the tokens were cached, have Preprocessor replace them
1760	// with the annotation token. We don't need to do this if we've
1761	// just reverted back to a prior state.
1762	if (IsNewAnnotation)
1763	PP.AnnotateCachedTokens(Tok);
1764	}
1765
1766	/// Attempt to classify the name at the current token position. This may
1767	/// form a type, scope or primary expression annotation, or replace the token
1768	/// with a typo-corrected keyword. This is only appropriate when the current
1769	/// name must refer to an entity which has already been declared.
1770	///
1771	/// \param CCC Indicates how to perform typo-correction for this name. If NULL,
1772	/// no typo correction will be performed.
1773	/// \param AllowImplicitTypename Whether we are in a context where a dependent
1774	/// nested-name-specifier without typename is treated as a type (e.g.
1775	/// T::type).
1776	Parser::AnnotatedNameKind
1777	Parser::TryAnnotateName(CorrectionCandidateCallback *CCC,
1778	ImplicitTypenameContext AllowImplicitTypename) {
1779	assert(Tok.is(tok::identifier) || Tok.is(tok::annot_cxxscope));
1780
1781	const bool EnteringContext = false;
1782	const bool WasScopeAnnotation = Tok.is(K: tok::annot_cxxscope);
1783
1784	CXXScopeSpec SS;
1785	if (getLangOpts().CPlusPlus &&
1786	ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
1787	/*ObjectHasErrors=*/false,
1788	EnteringContext))
1789	return ANK_Error;
1790
1791	if (Tok.isNot(K: tok::identifier) || SS.isInvalid()) {
1792	if (TryAnnotateTypeOrScopeTokenAfterScopeSpec(SS, IsNewScope: !WasScopeAnnotation,
1793	AllowImplicitTypename))
1794	return ANK_Error;
1795	return ANK_Unresolved;
1796	}
1797
1798	IdentifierInfo *Name = Tok.getIdentifierInfo();
1799	SourceLocation NameLoc = Tok.getLocation();
1800
1801	// FIXME: Move the tentative declaration logic into ClassifyName so we can
1802	// typo-correct to tentatively-declared identifiers.
1803	if (isTentativelyDeclared(II: Name) && SS.isEmpty()) {
1804	// Identifier has been tentatively declared, and thus cannot be resolved as
1805	// an expression. Fall back to annotating it as a type.
1806	if (TryAnnotateTypeOrScopeTokenAfterScopeSpec(SS, IsNewScope: !WasScopeAnnotation,
1807	AllowImplicitTypename))
1808	return ANK_Error;
1809	return Tok.is(K: tok::annot_typename) ? ANK_Success : ANK_TentativeDecl;
1810	}
1811
1812	Token Next = NextToken();
1813
1814	// Look up and classify the identifier. We don't perform any typo-correction
1815	// after a scope specifier, because in general we can't recover from typos
1816	// there (eg, after correcting 'A::template B<X>::C' [sic], we would need to
1817	// jump back into scope specifier parsing).
1818	Sema::NameClassification Classification = Actions.ClassifyName(
1819	S: getCurScope(), SS, Name, NameLoc, NextToken: Next, CCC: SS.isEmpty() ? CCC : nullptr);
1820
1821	// If name lookup found nothing and we guessed that this was a template name,
1822	// double-check before committing to that interpretation. C++20 requires that
1823	// we interpret this as a template-id if it can be, but if it can't be, then
1824	// this is an error recovery case.
1825	if (Classification.getKind() == Sema::NC_UndeclaredTemplate &&
1826	isTemplateArgumentList(TokensToSkip: 1) == TPResult::False) {
1827	// It's not a template-id; re-classify without the '<' as a hint.
1828	Token FakeNext = Next;
1829	FakeNext.setKind(tok::unknown);
1830	Classification =
1831	Actions.ClassifyName(S: getCurScope(), SS, Name, NameLoc, NextToken: FakeNext,
1832	CCC: SS.isEmpty() ? CCC : nullptr);
1833	}
1834
1835	switch (Classification.getKind()) {
1836	case Sema::NC_Error:
1837	return ANK_Error;
1838
1839	case Sema::NC_Keyword:
1840	// The identifier was typo-corrected to a keyword.
1841	Tok.setIdentifierInfo(Name);
1842	Tok.setKind(Name->getTokenID());
1843	PP.TypoCorrectToken(Tok);
1844	if (SS.isNotEmpty())
1845	AnnotateScopeToken(SS, IsNewAnnotation: !WasScopeAnnotation);
1846	// We've "annotated" this as a keyword.
1847	return ANK_Success;
1848
1849	case Sema::NC_Unknown:
1850	// It's not something we know about. Leave it unannotated.
1851	break;
1852
1853	case Sema::NC_Type: {
1854	if (TryAltiVecVectorToken())
1855	// vector has been found as a type id when altivec is enabled but
1856	// this is followed by a declaration specifier so this is really the
1857	// altivec vector token. Leave it unannotated.
1858	break;
1859	SourceLocation BeginLoc = NameLoc;
1860	if (SS.isNotEmpty())
1861	BeginLoc = SS.getBeginLoc();
1862
1863	/// An Objective-C object type followed by '<' is a specialization of
1864	/// a parameterized class type or a protocol-qualified type.
1865	ParsedType Ty = Classification.getType();
1866	if (getLangOpts().ObjC && NextToken().is(K: tok::less) &&
1867	(Ty.get()->isObjCObjectType() ||
1868	Ty.get()->isObjCObjectPointerType())) {
1869	// Consume the name.
1870	SourceLocation IdentifierLoc = ConsumeToken();
1871	SourceLocation NewEndLoc;
1872	TypeResult NewType
1873	= parseObjCTypeArgsAndProtocolQualifiers(loc: IdentifierLoc, type: Ty,
1874	/*consumeLastToken=*/false,
1875	endLoc&: NewEndLoc);
1876	if (NewType.isUsable())
1877	Ty = NewType.get();
1878	else if (Tok.is(K: tok::eof)) // Nothing to do here, bail out...
1879	return ANK_Error;
1880	}
1881
1882	Tok.setKind(tok::annot_typename);
1883	setTypeAnnotation(Tok, T: Ty);
1884	Tok.setAnnotationEndLoc(Tok.getLocation());
1885	Tok.setLocation(BeginLoc);
1886	PP.AnnotateCachedTokens(Tok);
1887	return ANK_Success;
1888	}
1889
1890	case Sema::NC_OverloadSet:
1891	Tok.setKind(tok::annot_overload_set);
1892	setExprAnnotation(Tok, ER: Classification.getExpression());
1893	Tok.setAnnotationEndLoc(NameLoc);
1894	if (SS.isNotEmpty())
1895	Tok.setLocation(SS.getBeginLoc());
1896	PP.AnnotateCachedTokens(Tok);
1897	return ANK_Success;
1898
1899	case Sema::NC_NonType:
1900	if (TryAltiVecVectorToken())
1901	// vector has been found as a non-type id when altivec is enabled but
1902	// this is followed by a declaration specifier so this is really the
1903	// altivec vector token. Leave it unannotated.
1904	break;
1905	Tok.setKind(tok::annot_non_type);
1906	setNonTypeAnnotation(Tok, ND: Classification.getNonTypeDecl());
1907	Tok.setLocation(NameLoc);
1908	Tok.setAnnotationEndLoc(NameLoc);
1909	PP.AnnotateCachedTokens(Tok);
1910	if (SS.isNotEmpty())
1911	AnnotateScopeToken(SS, IsNewAnnotation: !WasScopeAnnotation);
1912	return ANK_Success;
1913
1914	case Sema::NC_UndeclaredNonType:
1915	case Sema::NC_DependentNonType:
1916	Tok.setKind(Classification.getKind() == Sema::NC_UndeclaredNonType
1917	? tok::annot_non_type_undeclared
1918	: tok::annot_non_type_dependent);
1919	setIdentifierAnnotation(Tok, ND: Name);
1920	Tok.setLocation(NameLoc);
1921	Tok.setAnnotationEndLoc(NameLoc);
1922	PP.AnnotateCachedTokens(Tok);
1923	if (SS.isNotEmpty())
1924	AnnotateScopeToken(SS, IsNewAnnotation: !WasScopeAnnotation);
1925	return ANK_Success;
1926
1927	case Sema::NC_TypeTemplate:
1928	if (Next.isNot(K: tok::less)) {
1929	// This may be a type template being used as a template template argument.
1930	if (SS.isNotEmpty())
1931	AnnotateScopeToken(SS, IsNewAnnotation: !WasScopeAnnotation);
1932	return ANK_TemplateName;
1933	}
1934	[[fallthrough]];
1935	case Sema::NC_Concept:
1936	case Sema::NC_VarTemplate:
1937	case Sema::NC_FunctionTemplate:
1938	case Sema::NC_UndeclaredTemplate: {
1939	bool IsConceptName = Classification.getKind() == Sema::NC_Concept;
1940	// We have a template name followed by '<'. Consume the identifier token so
1941	// we reach the '<' and annotate it.
1942	if (Next.is(K: tok::less))
1943	ConsumeToken();
1944	UnqualifiedId Id;
1945	Id.setIdentifier(Id: Name, IdLoc: NameLoc);
1946	if (AnnotateTemplateIdToken(
1947	Template: TemplateTy::make(P: Classification.getTemplateName()),
1948	TNK: Classification.getTemplateNameKind(), SS, TemplateKWLoc: SourceLocation(), TemplateName&: Id,
1949	/*AllowTypeAnnotation=*/!IsConceptName,
1950	/*TypeConstraint=*/IsConceptName))
1951	return ANK_Error;
1952	if (SS.isNotEmpty())
1953	AnnotateScopeToken(SS, IsNewAnnotation: !WasScopeAnnotation);
1954	return ANK_Success;
1955	}
1956	}
1957
1958	// Unable to classify the name, but maybe we can annotate a scope specifier.
1959	if (SS.isNotEmpty())
1960	AnnotateScopeToken(SS, IsNewAnnotation: !WasScopeAnnotation);
1961	return ANK_Unresolved;
1962	}
1963
1964	bool Parser::TryKeywordIdentFallback(bool DisableKeyword) {
1965	assert(Tok.isNot(tok::identifier));
1966	Diag(Tok, diag::ext_keyword_as_ident)
1967	<< PP.getSpelling(Tok)
1968	<< DisableKeyword;
1969	if (DisableKeyword)
1970	Tok.getIdentifierInfo()->revertTokenIDToIdentifier();
1971	Tok.setKind(tok::identifier);
1972	return true;
1973	}
1974
1975	/// TryAnnotateTypeOrScopeToken - If the current token position is on a
1976	/// typename (possibly qualified in C++) or a C++ scope specifier not followed
1977	/// by a typename, TryAnnotateTypeOrScopeToken will replace one or more tokens
1978	/// with a single annotation token representing the typename or C++ scope
1979	/// respectively.
1980	/// This simplifies handling of C++ scope specifiers and allows efficient
1981	/// backtracking without the need to re-parse and resolve nested-names and
1982	/// typenames.
1983	/// It will mainly be called when we expect to treat identifiers as typenames
1984	/// (if they are typenames). For example, in C we do not expect identifiers
1985	/// inside expressions to be treated as typenames so it will not be called
1986	/// for expressions in C.
1987	/// The benefit for C/ObjC is that a typename will be annotated and
1988	/// Actions.getTypeName will not be needed to be called again (e.g. getTypeName
1989	/// will not be called twice, once to check whether we have a declaration
1990	/// specifier, and another one to get the actual type inside
1991	/// ParseDeclarationSpecifiers).
1992	///
1993	/// This returns true if an error occurred.
1994	///
1995	/// Note that this routine emits an error if you call it with ::new or ::delete
1996	/// as the current tokens, so only call it in contexts where these are invalid.
1997	bool Parser::TryAnnotateTypeOrScopeToken(
1998	ImplicitTypenameContext AllowImplicitTypename) {
1999	assert((Tok.is(tok::identifier) || Tok.is(tok::coloncolon) ||
2000	Tok.is(tok::kw_typename) || Tok.is(tok::annot_cxxscope) ||
2001	Tok.is(tok::kw_decltype) || Tok.is(tok::annot_template_id) ||
2002	Tok.is(tok::kw___super) || Tok.is(tok::kw_auto) ||
2003	Tok.is(tok::annot_pack_indexing_type)) &&
2004	"Cannot be a type or scope token!");
2005
2006	if (Tok.is(K: tok::kw_typename)) {
2007	// MSVC lets you do stuff like:
2008	// typename typedef T_::D D;
2009	//
2010	// We will consume the typedef token here and put it back after we have
2011	// parsed the first identifier, transforming it into something more like:
2012	// typename T_::D typedef D;
2013	if (getLangOpts().MSVCCompat && NextToken().is(K: tok::kw_typedef)) {
2014	Token TypedefToken;
2015	PP.Lex(Result&: TypedefToken);
2016	bool Result = TryAnnotateTypeOrScopeToken(AllowImplicitTypename);
2017	PP.EnterToken(Tok, /*IsReinject=*/true);
2018	Tok = TypedefToken;
2019	if (!Result)
2020	Diag(Tok.getLocation(), diag::warn_expected_qualified_after_typename);
2021	return Result;
2022	}
2023
2024	// Parse a C++ typename-specifier, e.g., "typename T::type".
2025	//
2026	// typename-specifier:
2027	// 'typename' '::' [opt] nested-name-specifier identifier
2028	// 'typename' '::' [opt] nested-name-specifier template [opt]
2029	// simple-template-id
2030	SourceLocation TypenameLoc = ConsumeToken();
2031	CXXScopeSpec SS;
2032	if (ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
2033	/*ObjectHasErrors=*/false,
2034	/*EnteringContext=*/false, MayBePseudoDestructor: nullptr,
2035	/*IsTypename*/ true))
2036	return true;
2037	if (SS.isEmpty()) {
2038	if (Tok.is(K: tok::identifier) || Tok.is(K: tok::annot_template_id) ||
2039	Tok.is(K: tok::annot_decltype)) {
2040	// Attempt to recover by skipping the invalid 'typename'
2041	if (Tok.is(K: tok::annot_decltype) ||
2042	(!TryAnnotateTypeOrScopeToken(AllowImplicitTypename) &&
2043	Tok.isAnnotation())) {
2044	unsigned DiagID = diag::err_expected_qualified_after_typename;
2045	// MS compatibility: MSVC permits using known types with typename.
2046	// e.g. "typedef typename T* pointer_type"
2047	if (getLangOpts().MicrosoftExt)
2048	DiagID = diag::warn_expected_qualified_after_typename;
2049	Diag(Loc: Tok.getLocation(), DiagID);
2050	return false;
2051	}
2052	}
2053	if (Tok.isEditorPlaceholder())
2054	return true;
2055
2056	Diag(Tok.getLocation(), diag::err_expected_qualified_after_typename);
2057	return true;
2058	}
2059
2060	TypeResult Ty;
2061	if (Tok.is(K: tok::identifier)) {
2062	// FIXME: check whether the next token is '<', first!
2063	Ty = Actions.ActOnTypenameType(S: getCurScope(), TypenameLoc, SS,
2064	II: *Tok.getIdentifierInfo(),
2065	IdLoc: Tok.getLocation());
2066	} else if (Tok.is(K: tok::annot_template_id)) {
2067	TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(tok: Tok);
2068	if (!TemplateId->mightBeType()) {
2069	Diag(Tok, diag::err_typename_refers_to_non_type_template)
2070	<< Tok.getAnnotationRange();
2071	return true;
2072	}
2073
2074	ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
2075	TemplateId->NumArgs);
2076
2077	Ty = TemplateId->isInvalid()
2078	? TypeError()
2079	: Actions.ActOnTypenameType(
2080	S: getCurScope(), TypenameLoc, SS, TemplateLoc: TemplateId->TemplateKWLoc,
2081	TemplateName: TemplateId->Template, TemplateII: TemplateId->Name,
2082	TemplateIILoc: TemplateId->TemplateNameLoc, LAngleLoc: TemplateId->LAngleLoc,
2083	TemplateArgs: TemplateArgsPtr, RAngleLoc: TemplateId->RAngleLoc);
2084	} else {
2085	Diag(Tok, diag::err_expected_type_name_after_typename)
2086	<< SS.getRange();
2087	return true;
2088	}
2089
2090	SourceLocation EndLoc = Tok.getLastLoc();
2091	Tok.setKind(tok::annot_typename);
2092	setTypeAnnotation(Tok, T: Ty);
2093	Tok.setAnnotationEndLoc(EndLoc);
2094	Tok.setLocation(TypenameLoc);
2095	PP.AnnotateCachedTokens(Tok);
2096	return false;
2097	}
2098
2099	// Remembers whether the token was originally a scope annotation.
2100	bool WasScopeAnnotation = Tok.is(K: tok::annot_cxxscope);
2101
2102	CXXScopeSpec SS;
2103	if (getLangOpts().CPlusPlus)
2104	if (ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
2105	/*ObjectHasErrors=*/false,
2106	/*EnteringContext*/ false))
2107	return true;
2108
2109	return TryAnnotateTypeOrScopeTokenAfterScopeSpec(SS, IsNewScope: !WasScopeAnnotation,
2110	AllowImplicitTypename);
2111	}
2112
2113	/// Try to annotate a type or scope token, having already parsed an
2114	/// optional scope specifier. \p IsNewScope should be \c true unless the scope
2115	/// specifier was extracted from an existing tok::annot_cxxscope annotation.
2116	bool Parser::TryAnnotateTypeOrScopeTokenAfterScopeSpec(
2117	CXXScopeSpec &SS, bool IsNewScope,
2118	ImplicitTypenameContext AllowImplicitTypename) {
2119	if (Tok.is(K: tok::identifier)) {
2120	// Determine whether the identifier is a type name.
2121	if (ParsedType Ty = Actions.getTypeName(
2122	II: *Tok.getIdentifierInfo(), NameLoc: Tok.getLocation(), S: getCurScope(), SS: &SS,
2123	isClassName: false, HasTrailingDot: NextToken().is(K: tok::period), ObjectType: nullptr,
2124	/*IsCtorOrDtorName=*/false,
2125	/*NonTrivialTypeSourceInfo=*/WantNontrivialTypeSourceInfo: true,
2126	/*IsClassTemplateDeductionContext=*/true, AllowImplicitTypename)) {
2127	SourceLocation BeginLoc = Tok.getLocation();
2128	if (SS.isNotEmpty()) // it was a C++ qualified type name.
2129	BeginLoc = SS.getBeginLoc();
2130
2131	/// An Objective-C object type followed by '<' is a specialization of
2132	/// a parameterized class type or a protocol-qualified type.
2133	if (getLangOpts().ObjC && NextToken().is(K: tok::less) &&
2134	(Ty.get()->isObjCObjectType() ||
2135	Ty.get()->isObjCObjectPointerType())) {
2136	// Consume the name.
2137	SourceLocation IdentifierLoc = ConsumeToken();
2138	SourceLocation NewEndLoc;
2139	TypeResult NewType
2140	= parseObjCTypeArgsAndProtocolQualifiers(loc: IdentifierLoc, type: Ty,
2141	/*consumeLastToken=*/false,
2142	endLoc&: NewEndLoc);
2143	if (NewType.isUsable())
2144	Ty = NewType.get();
2145	else if (Tok.is(K: tok::eof)) // Nothing to do here, bail out...
2146	return false;
2147	}
2148
2149	// This is a typename. Replace the current token in-place with an
2150	// annotation type token.
2151	Tok.setKind(tok::annot_typename);
2152	setTypeAnnotation(Tok, T: Ty);
2153	Tok.setAnnotationEndLoc(Tok.getLocation());
2154	Tok.setLocation(BeginLoc);
2155
2156	// In case the tokens were cached, have Preprocessor replace
2157	// them with the annotation token.
2158	PP.AnnotateCachedTokens(Tok);
2159	return false;
2160	}
2161
2162	if (!getLangOpts().CPlusPlus) {
2163	// If we're in C, the only place we can have :: tokens is C23
2164	// attribute which is parsed elsewhere. If the identifier is not a type,
2165	// then it can't be scope either, just early exit.
2166	return false;
2167	}
2168
2169	// If this is a template-id, annotate with a template-id or type token.
2170	// FIXME: This appears to be dead code. We already have formed template-id
2171	// tokens when parsing the scope specifier; this can never form a new one.
2172	if (NextToken().is(K: tok::less)) {
2173	TemplateTy Template;
2174	UnqualifiedId TemplateName;
2175	TemplateName.setIdentifier(Id: Tok.getIdentifierInfo(), IdLoc: Tok.getLocation());
2176	bool MemberOfUnknownSpecialization;
2177	if (TemplateNameKind TNK = Actions.isTemplateName(
2178	S: getCurScope(), SS,
2179	/*hasTemplateKeyword=*/false, Name: TemplateName,
2180	/*ObjectType=*/nullptr, /*EnteringContext*/false, Template,
2181	MemberOfUnknownSpecialization)) {
2182	// Only annotate an undeclared template name as a template-id if the
2183	// following tokens have the form of a template argument list.
2184	if (TNK != TNK_Undeclared_template ||
2185	isTemplateArgumentList(TokensToSkip: 1) != TPResult::False) {
2186	// Consume the identifier.
2187	ConsumeToken();
2188	if (AnnotateTemplateIdToken(Template, TNK, SS, TemplateKWLoc: SourceLocation(),
2189	TemplateName)) {
2190	// If an unrecoverable error occurred, we need to return true here,
2191	// because the token stream is in a damaged state. We may not
2192	// return a valid identifier.
2193	return true;
2194	}
2195	}
2196	}
2197	}
2198
2199	// The current token, which is either an identifier or a
2200	// template-id, is not part of the annotation. Fall through to
2201	// push that token back into the stream and complete the C++ scope
2202	// specifier annotation.
2203	}
2204
2205	if (Tok.is(K: tok::annot_template_id)) {
2206	TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(tok: Tok);
2207	if (TemplateId->Kind == TNK_Type_template) {
2208	// A template-id that refers to a type was parsed into a
2209	// template-id annotation in a context where we weren't allowed
2210	// to produce a type annotation token. Update the template-id
2211	// annotation token to a type annotation token now.
2212	AnnotateTemplateIdTokenAsType(SS, AllowImplicitTypename);
2213	return false;
2214	}
2215	}
2216
2217	if (SS.isEmpty())
2218	return false;
2219
2220	// A C++ scope specifier that isn't followed by a typename.
2221	AnnotateScopeToken(SS, IsNewAnnotation: IsNewScope);
2222	return false;
2223	}
2224
2225	/// TryAnnotateScopeToken - Like TryAnnotateTypeOrScopeToken but only
2226	/// annotates C++ scope specifiers and template-ids. This returns
2227	/// true if there was an error that could not be recovered from.
2228	///
2229	/// Note that this routine emits an error if you call it with ::new or ::delete
2230	/// as the current tokens, so only call it in contexts where these are invalid.
2231	bool Parser::TryAnnotateCXXScopeToken(bool EnteringContext) {
2232	assert(getLangOpts().CPlusPlus &&
2233	"Call sites of this function should be guarded by checking for C++");
2234	assert(MightBeCXXScopeToken() && "Cannot be a type or scope token!");
2235
2236	CXXScopeSpec SS;
2237	if (ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
2238	/*ObjectHasErrors=*/false,
2239	EnteringContext))
2240	return true;
2241	if (SS.isEmpty())
2242	return false;
2243
2244	AnnotateScopeToken(SS, IsNewAnnotation: true);
2245	return false;
2246	}
2247
2248	bool Parser::isTokenEqualOrEqualTypo() {
2249	tok::TokenKind Kind = Tok.getKind();
2250	switch (Kind) {
2251	default:
2252	return false;
2253	case tok::ampequal: // &=
2254	case tok::starequal: // *=
2255	case tok::plusequal: // +=
2256	case tok::minusequal: // -=
2257	case tok::exclaimequal: // !=
2258	case tok::slashequal: // /=
2259	case tok::percentequal: // %=
2260	case tok::lessequal: // <=
2261	case tok::lesslessequal: // <<=
2262	case tok::greaterequal: // >=
2263	case tok::greatergreaterequal: // >>=
2264	case tok::caretequal: // ^=
2265	case tok::pipeequal: // |=
2266	case tok::equalequal: // ==
2267	Diag(Tok, diag::err_invalid_token_after_declarator_suggest_equal)
2268	<< Kind
2269	<< FixItHint::CreateReplacement(SourceRange(Tok.getLocation()), "=");
2270	[[fallthrough]];
2271	case tok::equal:
2272	return true;
2273	}
2274	}
2275
2276	SourceLocation Parser::handleUnexpectedCodeCompletionToken() {
2277	assert(Tok.is(tok::code_completion));
2278	PrevTokLocation = Tok.getLocation();
2279
2280	for (Scope *S = getCurScope(); S; S = S->getParent()) {
2281	if (S->isFunctionScope()) {
2282	cutOffParsing();
2283	Actions.CodeCompleteOrdinaryName(S: getCurScope(),
2284	CompletionContext: Sema::PCC_RecoveryInFunction);
2285	return PrevTokLocation;
2286	}
2287
2288	if (S->isClassScope()) {
2289	cutOffParsing();
2290	Actions.CodeCompleteOrdinaryName(S: getCurScope(), CompletionContext: Sema::PCC_Class);
2291	return PrevTokLocation;
2292	}
2293	}
2294
2295	cutOffParsing();
2296	Actions.CodeCompleteOrdinaryName(S: getCurScope(), CompletionContext: Sema::PCC_Namespace);
2297	return PrevTokLocation;
2298	}
2299
2300	// Code-completion pass-through functions
2301
2302	void Parser::CodeCompleteDirective(bool InConditional) {
2303	Actions.CodeCompletePreprocessorDirective(InConditional);
2304	}
2305
2306	void Parser::CodeCompleteInConditionalExclusion() {
2307	Actions.CodeCompleteInPreprocessorConditionalExclusion(S: getCurScope());
2308	}
2309
2310	void Parser::CodeCompleteMacroName(bool IsDefinition) {
2311	Actions.CodeCompletePreprocessorMacroName(IsDefinition);
2312	}
2313
2314	void Parser::CodeCompletePreprocessorExpression() {
2315	Actions.CodeCompletePreprocessorExpression();
2316	}
2317
2318	void Parser::CodeCompleteMacroArgument(IdentifierInfo *Macro,
2319	MacroInfo *MacroInfo,
2320	unsigned ArgumentIndex) {
2321	Actions.CodeCompletePreprocessorMacroArgument(S: getCurScope(), Macro, MacroInfo,
2322	Argument: ArgumentIndex);
2323	}
2324
2325	void Parser::CodeCompleteIncludedFile(llvm::StringRef Dir, bool IsAngled) {
2326	Actions.CodeCompleteIncludedFile(Dir, IsAngled);
2327	}
2328
2329	void Parser::CodeCompleteNaturalLanguage() {
2330	Actions.CodeCompleteNaturalLanguage();
2331	}
2332
2333	bool Parser::ParseMicrosoftIfExistsCondition(IfExistsCondition& Result) {
2334	assert((Tok.is(tok::kw___if_exists) || Tok.is(tok::kw___if_not_exists)) &&
2335	"Expected '__if_exists' or '__if_not_exists'");
2336	Result.IsIfExists = Tok.is(K: tok::kw___if_exists);
2337	Result.KeywordLoc = ConsumeToken();
2338
2339	BalancedDelimiterTracker T(*this, tok::l_paren);
2340	if (T.consumeOpen()) {
2341	Diag(Tok, diag::err_expected_lparen_after)
2342	<< (Result.IsIfExists? "__if_exists" : "__if_not_exists");
2343	return true;
2344	}
2345
2346	// Parse nested-name-specifier.
2347	if (getLangOpts().CPlusPlus)
2348	ParseOptionalCXXScopeSpecifier(SS&: Result.SS, /*ObjectType=*/nullptr,
2349	/*ObjectHasErrors=*/false,
2350	/*EnteringContext=*/false);
2351
2352	// Check nested-name specifier.
2353	if (Result.SS.isInvalid()) {
2354	T.skipToEnd();
2355	return true;
2356	}
2357
2358	// Parse the unqualified-id.
2359	SourceLocation TemplateKWLoc; // FIXME: parsed, but unused.
2360	if (ParseUnqualifiedId(SS&: Result.SS, /*ObjectType=*/nullptr,
2361	/*ObjectHadErrors=*/false, /*EnteringContext*/ false,
2362	/*AllowDestructorName*/ true,
2363	/*AllowConstructorName*/ true,
2364	/*AllowDeductionGuide*/ false, TemplateKWLoc: &TemplateKWLoc,
2365	Result&: Result.Name)) {
2366	T.skipToEnd();
2367	return true;
2368	}
2369
2370	if (T.consumeClose())
2371	return true;
2372
2373	// Check if the symbol exists.
2374	switch (Actions.CheckMicrosoftIfExistsSymbol(S: getCurScope(), KeywordLoc: Result.KeywordLoc,
2375	IsIfExists: Result.IsIfExists, SS&: Result.SS,
2376	Name&: Result.Name)) {
2377	case Sema::IER_Exists:
2378	Result.Behavior = Result.IsIfExists ? IEB_Parse : IEB_Skip;
2379	break;
2380
2381	case Sema::IER_DoesNotExist:
2382	Result.Behavior = !Result.IsIfExists ? IEB_Parse : IEB_Skip;
2383	break;
2384
2385	case Sema::IER_Dependent:
2386	Result.Behavior = IEB_Dependent;
2387	break;
2388
2389	case Sema::IER_Error:
2390	return true;
2391	}
2392
2393	return false;
2394	}
2395
2396	void Parser::ParseMicrosoftIfExistsExternalDeclaration() {
2397	IfExistsCondition Result;
2398	if (ParseMicrosoftIfExistsCondition(Result))
2399	return;
2400
2401	BalancedDelimiterTracker Braces(*this, tok::l_brace);
2402	if (Braces.consumeOpen()) {
2403	Diag(Tok, diag::err_expected) << tok::l_brace;
2404	return;
2405	}
2406
2407	switch (Result.Behavior) {
2408	case IEB_Parse:
2409	// Parse declarations below.
2410	break;
2411
2412	case IEB_Dependent:
2413	llvm_unreachable("Cannot have a dependent external declaration");
2414
2415	case IEB_Skip:
2416	Braces.skipToEnd();
2417	return;
2418	}
2419
2420	// Parse the declarations.
2421	// FIXME: Support module import within __if_exists?
2422	while (Tok.isNot(K: tok::r_brace) && !isEofOrEom()) {
2423	ParsedAttributes Attrs(AttrFactory);
2424	MaybeParseCXX11Attributes(Attrs);
2425	ParsedAttributes EmptyDeclSpecAttrs(AttrFactory);
2426	DeclGroupPtrTy Result = ParseExternalDeclaration(Attrs, DeclSpecAttrs&: EmptyDeclSpecAttrs);
2427	if (Result && !getCurScope()->getParent())
2428	Actions.getASTConsumer().HandleTopLevelDecl(D: Result.get());
2429	}
2430	Braces.consumeClose();
2431	}
2432
2433	/// Parse a declaration beginning with the 'module' keyword or C++20
2434	/// context-sensitive keyword (optionally preceded by 'export').
2435	///
2436	/// module-declaration: [C++20]
2437	/// 'export'[opt] 'module' module-name attribute-specifier-seq[opt] ';'
2438	///
2439	/// global-module-fragment: [C++2a]
2440	/// 'module' ';' top-level-declaration-seq[opt]
2441	/// module-declaration: [C++2a]
2442	/// 'export'[opt] 'module' module-name module-partition[opt]
2443	/// attribute-specifier-seq[opt] ';'
2444	/// private-module-fragment: [C++2a]
2445	/// 'module' ':' 'private' ';' top-level-declaration-seq[opt]
2446	Parser::DeclGroupPtrTy
2447	Parser::ParseModuleDecl(Sema::ModuleImportState &ImportState) {
2448	SourceLocation StartLoc = Tok.getLocation();
2449
2450	Sema::ModuleDeclKind MDK = TryConsumeToken(Expected: tok::kw_export)
2451	? Sema::ModuleDeclKind::Interface
2452	: Sema::ModuleDeclKind::Implementation;
2453
2454	assert(
2455	(Tok.is(tok::kw_module) ||
2456	(Tok.is(tok::identifier) && Tok.getIdentifierInfo() == Ident_module)) &&
2457	"not a module declaration");
2458	SourceLocation ModuleLoc = ConsumeToken();
2459
2460	// Attributes appear after the module name, not before.
2461	// FIXME: Suggest moving the attributes later with a fixit.
2462	DiagnoseAndSkipCXX11Attributes();
2463
2464	// Parse a global-module-fragment, if present.
2465	if (getLangOpts().CPlusPlusModules && Tok.is(K: tok::semi)) {
2466	SourceLocation SemiLoc = ConsumeToken();
2467	if (ImportState != Sema::ModuleImportState::FirstDecl) {
2468	Diag(StartLoc, diag::err_global_module_introducer_not_at_start)
2469	<< SourceRange(StartLoc, SemiLoc);
2470	return nullptr;
2471	}
2472	if (MDK == Sema::ModuleDeclKind::Interface) {
2473	Diag(StartLoc, diag::err_module_fragment_exported)
2474	<< /*global*/0 << FixItHint::CreateRemoval(StartLoc);
2475	}
2476	ImportState = Sema::ModuleImportState::GlobalFragment;
2477	return Actions.ActOnGlobalModuleFragmentDecl(ModuleLoc);
2478	}
2479
2480	// Parse a private-module-fragment, if present.
2481	if (getLangOpts().CPlusPlusModules && Tok.is(K: tok::colon) &&
2482	NextToken().is(K: tok::kw_private)) {
2483	if (MDK == Sema::ModuleDeclKind::Interface) {
2484	Diag(StartLoc, diag::err_module_fragment_exported)
2485	<< /*private*/1 << FixItHint::CreateRemoval(StartLoc);
2486	}
2487	ConsumeToken();
2488	SourceLocation PrivateLoc = ConsumeToken();
2489	DiagnoseAndSkipCXX11Attributes();
2490	ExpectAndConsumeSemi(diag::err_private_module_fragment_expected_semi);
2491	ImportState = ImportState == Sema::ModuleImportState::ImportAllowed
2492	? Sema::ModuleImportState::PrivateFragmentImportAllowed
2493	: Sema::ModuleImportState::PrivateFragmentImportFinished;
2494	return Actions.ActOnPrivateModuleFragmentDecl(ModuleLoc, PrivateLoc);
2495	}
2496
2497	SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Path;
2498	if (ParseModuleName(UseLoc: ModuleLoc, Path, /*IsImport*/ false))
2499	return nullptr;
2500
2501	// Parse the optional module-partition.
2502	SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Partition;
2503	if (Tok.is(K: tok::colon)) {
2504	SourceLocation ColonLoc = ConsumeToken();
2505	if (!getLangOpts().CPlusPlusModules)
2506	Diag(ColonLoc, diag::err_unsupported_module_partition)
2507	<< SourceRange(ColonLoc, Partition.back().second);
2508	// Recover by ignoring the partition name.
2509	else if (ParseModuleName(UseLoc: ModuleLoc, Path&: Partition, /*IsImport*/ false))
2510	return nullptr;
2511	}
2512
2513	// We don't support any module attributes yet; just parse them and diagnose.
2514	ParsedAttributes Attrs(AttrFactory);
2515	MaybeParseCXX11Attributes(Attrs);
2516	ProhibitCXX11Attributes(Attrs, diag::err_attribute_not_module_attr,
2517	diag::err_keyword_not_module_attr,
2518	/*DiagnoseEmptyAttrs=*/false,
2519	/*WarnOnUnknownAttrs=*/true);
2520
2521	ExpectAndConsumeSemi(diag::err_module_expected_semi);
2522
2523	return Actions.ActOnModuleDecl(StartLoc, ModuleLoc, MDK, Path, Partition,
2524	ImportState);
2525	}
2526
2527	/// Parse a module import declaration. This is essentially the same for
2528	/// Objective-C and C++20 except for the leading '@' (in ObjC) and the
2529	/// trailing optional attributes (in C++).
2530	///
2531	/// [ObjC] @import declaration:
2532	/// '@' 'import' module-name ';'
2533	/// [ModTS] module-import-declaration:
2534	/// 'import' module-name attribute-specifier-seq[opt] ';'
2535	/// [C++20] module-import-declaration:
2536	/// 'export'[opt] 'import' module-name
2537	/// attribute-specifier-seq[opt] ';'
2538	/// 'export'[opt] 'import' module-partition
2539	/// attribute-specifier-seq[opt] ';'
2540	/// 'export'[opt] 'import' header-name
2541	/// attribute-specifier-seq[opt] ';'
2542	Decl *Parser::ParseModuleImport(SourceLocation AtLoc,
2543	Sema::ModuleImportState &ImportState) {
2544	SourceLocation StartLoc = AtLoc.isInvalid() ? Tok.getLocation() : AtLoc;
2545
2546	SourceLocation ExportLoc;
2547	TryConsumeToken(Expected: tok::kw_export, Loc&: ExportLoc);
2548
2549	assert((AtLoc.isInvalid() ? Tok.isOneOf(tok::kw_import, tok::identifier)
2550	: Tok.isObjCAtKeyword(tok::objc_import)) &&
2551	"Improper start to module import");
2552	bool IsObjCAtImport = Tok.isObjCAtKeyword(objcKey: tok::objc_import);
2553	SourceLocation ImportLoc = ConsumeToken();
2554
2555	// For C++20 modules, we can have "name" or ":Partition name" as valid input.
2556	SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Path;
2557	bool IsPartition = false;
2558	Module *HeaderUnit = nullptr;
2559	if (Tok.is(K: tok::header_name)) {
2560	// This is a header import that the preprocessor decided we should skip
2561	// because it was malformed in some way. Parse and ignore it; it's already
2562	// been diagnosed.
2563	ConsumeToken();
2564	} else if (Tok.is(K: tok::annot_header_unit)) {
2565	// This is a header import that the preprocessor mapped to a module import.
2566	HeaderUnit = reinterpret_cast<Module *>(Tok.getAnnotationValue());
2567	ConsumeAnnotationToken();
2568	} else if (Tok.is(K: tok::colon)) {
2569	SourceLocation ColonLoc = ConsumeToken();
2570	if (!getLangOpts().CPlusPlusModules)
2571	Diag(ColonLoc, diag::err_unsupported_module_partition)
2572	<< SourceRange(ColonLoc, Path.back().second);
2573	// Recover by leaving partition empty.
2574	else if (ParseModuleName(UseLoc: ColonLoc, Path, /*IsImport*/ true))
2575	return nullptr;
2576	else
2577	IsPartition = true;
2578	} else {
2579	if (ParseModuleName(UseLoc: ImportLoc, Path, /*IsImport*/ true))
2580	return nullptr;
2581	}
2582
2583	ParsedAttributes Attrs(AttrFactory);
2584	MaybeParseCXX11Attributes(Attrs);
2585	// We don't support any module import attributes yet.
2586	ProhibitCXX11Attributes(Attrs, diag::err_attribute_not_import_attr,
2587	diag::err_keyword_not_import_attr,
2588	/*DiagnoseEmptyAttrs=*/false,
2589	/*WarnOnUnknownAttrs=*/true);
2590
2591	if (PP.hadModuleLoaderFatalFailure()) {
2592	// With a fatal failure in the module loader, we abort parsing.
2593	cutOffParsing();
2594	return nullptr;
2595	}
2596
2597	// Diagnose mis-imports.
2598	bool SeenError = true;
2599	switch (ImportState) {
2600	case Sema::ModuleImportState::ImportAllowed:
2601	SeenError = false;
2602	break;
2603	case Sema::ModuleImportState::FirstDecl:
2604	// If we found an import decl as the first declaration, we must be not in
2605	// a C++20 module unit or we are in an invalid state.
2606	ImportState = Sema::ModuleImportState::NotACXX20Module;
2607	[[fallthrough]];
2608	case Sema::ModuleImportState::NotACXX20Module:
2609	// We can only import a partition within a module purview.
2610	if (IsPartition)
2611	Diag(ImportLoc, diag::err_partition_import_outside_module);
2612	else
2613	SeenError = false;
2614	break;
2615	case Sema::ModuleImportState::GlobalFragment:
2616	case Sema::ModuleImportState::PrivateFragmentImportAllowed:
2617	// We can only have pre-processor directives in the global module fragment
2618	// which allows pp-import, but not of a partition (since the global module
2619	// does not have partitions).
2620	// We cannot import a partition into a private module fragment, since
2621	// [module.private.frag]/1 disallows private module fragments in a multi-
2622	// TU module.
2623	if (IsPartition || (HeaderUnit && HeaderUnit->Kind !=
2624	Module::ModuleKind::ModuleHeaderUnit))
2625	Diag(ImportLoc, diag::err_import_in_wrong_fragment)
2626	<< IsPartition
2627	<< (ImportState == Sema::ModuleImportState::GlobalFragment ? 0 : 1);
2628	else
2629	SeenError = false;
2630	break;
2631	case Sema::ModuleImportState::ImportFinished:
2632	case Sema::ModuleImportState::PrivateFragmentImportFinished:
2633	if (getLangOpts().CPlusPlusModules)
2634	Diag(ImportLoc, diag::err_import_not_allowed_here);
2635	else
2636	SeenError = false;
2637	break;
2638	}
2639	if (SeenError) {
2640	ExpectAndConsumeSemi(diag::err_module_expected_semi);
2641	return nullptr;
2642	}
2643
2644	DeclResult Import;
2645	if (HeaderUnit)
2646	Import =
2647	Actions.ActOnModuleImport(StartLoc, ExportLoc, ImportLoc, M: HeaderUnit);
2648	else if (!Path.empty())
2649	Import = Actions.ActOnModuleImport(StartLoc, ExportLoc, ImportLoc, Path,
2650	IsPartition);
2651	ExpectAndConsumeSemi(diag::err_module_expected_semi);
2652	if (Import.isInvalid())
2653	return nullptr;
2654
2655	// Using '@import' in framework headers requires modules to be enabled so that
2656	// the header is parseable. Emit a warning to make the user aware.
2657	if (IsObjCAtImport && AtLoc.isValid()) {
2658	auto &SrcMgr = PP.getSourceManager();
2659	auto FE = SrcMgr.getFileEntryRefForID(FID: SrcMgr.getFileID(SpellingLoc: AtLoc));
2660	if (FE && llvm::sys::path::parent_path(FE->getDir().getName())
2661	.ends_with(".framework"))
2662	Diags.Report(AtLoc, diag::warn_atimport_in_framework_header);
2663	}
2664
2665	return Import.get();
2666	}
2667
2668	/// Parse a C++ / Objective-C module name (both forms use the same
2669	/// grammar).
2670	///
2671	/// module-name:
2672	/// module-name-qualifier[opt] identifier
2673	/// module-name-qualifier:
2674	/// module-name-qualifier[opt] identifier '.'
2675	bool Parser::ParseModuleName(
2676	SourceLocation UseLoc,
2677	SmallVectorImpl<std::pair<IdentifierInfo *, SourceLocation>> &Path,
2678	bool IsImport) {
2679	// Parse the module path.
2680	while (true) {
2681	if (!Tok.is(K: tok::identifier)) {
2682	if (Tok.is(K: tok::code_completion)) {
2683	cutOffParsing();
2684	Actions.CodeCompleteModuleImport(ImportLoc: UseLoc, Path);
2685	return true;
2686	}
2687
2688	Diag(Tok, diag::err_module_expected_ident) << IsImport;
2689	SkipUntil(T: tok::semi);
2690	return true;
2691	}
2692
2693	// Record this part of the module path.
2694	Path.push_back(Elt: std::make_pair(x: Tok.getIdentifierInfo(), y: Tok.getLocation()));
2695	ConsumeToken();
2696
2697	if (Tok.isNot(K: tok::period))
2698	return false;
2699
2700	ConsumeToken();
2701	}
2702	}
2703
2704	/// Try recover parser when module annotation appears where it must not
2705	/// be found.
2706	/// \returns false if the recover was successful and parsing may be continued, or
2707	/// true if parser must bail out to top level and handle the token there.
2708	bool Parser::parseMisplacedModuleImport() {
2709	while (true) {
2710	switch (Tok.getKind()) {
2711	case tok::annot_module_end:
2712	// If we recovered from a misplaced module begin, we expect to hit a
2713	// misplaced module end too. Stay in the current context when this
2714	// happens.
2715	if (MisplacedModuleBeginCount) {
2716	--MisplacedModuleBeginCount;
2717	Actions.ActOnAnnotModuleEnd(
2718	DirectiveLoc: Tok.getLocation(),
2719	Mod: reinterpret_cast<Module *>(Tok.getAnnotationValue()));
2720	ConsumeAnnotationToken();
2721	continue;
2722	}
2723	// Inform caller that recovery failed, the error must be handled at upper
2724	// level. This will generate the desired "missing '}' at end of module"
2725	// diagnostics on the way out.
2726	return true;
2727	case tok::annot_module_begin:
2728	// Recover by entering the module (Sema will diagnose).
2729	Actions.ActOnAnnotModuleBegin(
2730	DirectiveLoc: Tok.getLocation(),
2731	Mod: reinterpret_cast<Module *>(Tok.getAnnotationValue()));
2732	ConsumeAnnotationToken();
2733	++MisplacedModuleBeginCount;
2734	continue;
2735	case tok::annot_module_include:
2736	// Module import found where it should not be, for instance, inside a
2737	// namespace. Recover by importing the module.
2738	Actions.ActOnAnnotModuleInclude(
2739	DirectiveLoc: Tok.getLocation(),
2740	Mod: reinterpret_cast<Module *>(Tok.getAnnotationValue()));
2741	ConsumeAnnotationToken();
2742	// If there is another module import, process it.
2743	continue;
2744	default:
2745	return false;
2746	}
2747	}
2748	return false;
2749	}
2750
2751	void Parser::diagnoseUseOfC11Keyword(const Token &Tok) {
2752	// Warn that this is a C11 extension if in an older mode or if in C++.
2753	// Otherwise, warn that it is incompatible with standards before C11 if in
2754	// C11 or later.
2755	Diag(Tok, getLangOpts().C11 ? diag::warn_c11_compat_keyword
2756	: diag::ext_c11_feature)
2757	<< Tok.getName();
2758	}
2759
2760	bool BalancedDelimiterTracker::diagnoseOverflow() {
2761	P.Diag(P.Tok, diag::err_bracket_depth_exceeded)
2762	<< P.getLangOpts().BracketDepth;
2763	P.Diag(P.Tok, diag::note_bracket_depth);
2764	P.cutOffParsing();
2765	return true;
2766	}
2767
2768	bool BalancedDelimiterTracker::expectAndConsume(unsigned DiagID,
2769	const char *Msg,
2770	tok::TokenKind SkipToTok) {
2771	LOpen = P.Tok.getLocation();
2772	if (P.ExpectAndConsume(ExpectedTok: Kind, DiagID, Msg)) {
2773	if (SkipToTok != tok::unknown)
2774	P.SkipUntil(T: SkipToTok, Flags: Parser::StopAtSemi);
2775	return true;
2776	}
2777
2778	if (getDepth() < P.getLangOpts().BracketDepth)
2779	return false;
2780
2781	return diagnoseOverflow();
2782	}
2783
2784	bool BalancedDelimiterTracker::diagnoseMissingClose() {
2785	assert(!P.Tok.is(Close) && "Should have consumed closing delimiter");
2786
2787	if (P.Tok.is(tok::annot_module_end))
2788	P.Diag(P.Tok, diag::err_missing_before_module_end) << Close;
2789	else
2790	P.Diag(P.Tok, diag::err_expected) << Close;
2791	P.Diag(LOpen, diag::note_matching) << Kind;
2792
2793	// If we're not already at some kind of closing bracket, skip to our closing
2794	// token.
2795	if (P.Tok.isNot(K: tok::r_paren) && P.Tok.isNot(K: tok::r_brace) &&
2796	P.Tok.isNot(K: tok::r_square) &&
2797	P.SkipUntil(T1: Close, T2: FinalToken,
2798	Flags: Parser::StopAtSemi | Parser::StopBeforeMatch) &&
2799	P.Tok.is(K: Close))
2800	LClose = P.ConsumeAnyToken();
2801	return true;
2802	}
2803
2804	void BalancedDelimiterTracker::skipToEnd() {
2805	P.SkipUntil(T: Close, Flags: Parser::StopBeforeMatch);
2806	consumeClose();
2807	}
2808