1 //===--- ParseDecl.cpp - Declaration Parsing --------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 //  This file implements the Declaration portions of the Parser interfaces.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/Parse/Parser.h"
15 #include "RAIIObjectsForParser.h"
16 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/DeclTemplate.h"
18 #include "clang/Basic/AddressSpaces.h"
19 #include "clang/Basic/Attributes.h"
20 #include "clang/Basic/CharInfo.h"
21 #include "clang/Basic/TargetInfo.h"
22 #include "clang/Parse/ParseDiagnostic.h"
23 #include "clang/Sema/Lookup.h"
24 #include "clang/Sema/ParsedTemplate.h"
25 #include "clang/Sema/PrettyDeclStackTrace.h"
26 #include "clang/Sema/Scope.h"
27 #include "clang/Sema/SemaDiagnostic.h"
28 #include "llvm/ADT/Optional.h"
29 #include "llvm/ADT/SmallSet.h"
30 #include "llvm/ADT/SmallString.h"
31 #include "llvm/ADT/StringSwitch.h"
32 #include "llvm/Support/ScopedPrinter.h"
33 
34 using namespace clang;
35 
36 //===----------------------------------------------------------------------===//
37 // C99 6.7: Declarations.
38 //===----------------------------------------------------------------------===//
39 
40 /// ParseTypeName
41 ///       type-name: [C99 6.7.6]
42 ///         specifier-qualifier-list abstract-declarator[opt]
43 ///
44 /// Called type-id in C++.
45 TypeResult Parser::ParseTypeName(SourceRange *Range,
46                                  Declarator::TheContext Context,
47                                  AccessSpecifier AS,
48                                  Decl **OwnedType,
49                                  ParsedAttributes *Attrs) {
50   DeclSpecContext DSC = getDeclSpecContextFromDeclaratorContext(Context);
51   if (DSC == DSC_normal)
52     DSC = DSC_type_specifier;
53 
54   // Parse the common declaration-specifiers piece.
55   DeclSpec DS(AttrFactory);
56   if (Attrs)
57     DS.addAttributes(Attrs->getList());
58   ParseSpecifierQualifierList(DS, AS, DSC);
59   if (OwnedType)
60     *OwnedType = DS.isTypeSpecOwned() ? DS.getRepAsDecl() : nullptr;
61 
62   // Parse the abstract-declarator, if present.
63   Declarator DeclaratorInfo(DS, Context);
64   ParseDeclarator(DeclaratorInfo);
65   if (Range)
66     *Range = DeclaratorInfo.getSourceRange();
67 
68   if (DeclaratorInfo.isInvalidType())
69     return true;
70 
71   return Actions.ActOnTypeName(getCurScope(), DeclaratorInfo);
72 }
73 
74 /// isAttributeLateParsed - Return true if the attribute has arguments that
75 /// require late parsing.
76 static bool isAttributeLateParsed(const IdentifierInfo &II) {
77 #define CLANG_ATTR_LATE_PARSED_LIST
78     return llvm::StringSwitch<bool>(II.getName())
79 #include "clang/Parse/AttrParserStringSwitches.inc"
80         .Default(false);
81 #undef CLANG_ATTR_LATE_PARSED_LIST
82 }
83 
84 /// ParseGNUAttributes - Parse a non-empty attributes list.
85 ///
86 /// [GNU] attributes:
87 ///         attribute
88 ///         attributes attribute
89 ///
90 /// [GNU]  attribute:
91 ///          '__attribute__' '(' '(' attribute-list ')' ')'
92 ///
93 /// [GNU]  attribute-list:
94 ///          attrib
95 ///          attribute_list ',' attrib
96 ///
97 /// [GNU]  attrib:
98 ///          empty
99 ///          attrib-name
100 ///          attrib-name '(' identifier ')'
101 ///          attrib-name '(' identifier ',' nonempty-expr-list ')'
102 ///          attrib-name '(' argument-expression-list [C99 6.5.2] ')'
103 ///
104 /// [GNU]  attrib-name:
105 ///          identifier
106 ///          typespec
107 ///          typequal
108 ///          storageclass
109 ///
110 /// Whether an attribute takes an 'identifier' is determined by the
111 /// attrib-name. GCC's behavior here is not worth imitating:
112 ///
113 ///  * In C mode, if the attribute argument list starts with an identifier
114 ///    followed by a ',' or an ')', and the identifier doesn't resolve to
115 ///    a type, it is parsed as an identifier. If the attribute actually
116 ///    wanted an expression, it's out of luck (but it turns out that no
117 ///    attributes work that way, because C constant expressions are very
118 ///    limited).
119 ///  * In C++ mode, if the attribute argument list starts with an identifier,
120 ///    and the attribute *wants* an identifier, it is parsed as an identifier.
121 ///    At block scope, any additional tokens between the identifier and the
122 ///    ',' or ')' are ignored, otherwise they produce a parse error.
123 ///
124 /// We follow the C++ model, but don't allow junk after the identifier.
125 void Parser::ParseGNUAttributes(ParsedAttributes &attrs,
126                                 SourceLocation *endLoc,
127                                 LateParsedAttrList *LateAttrs,
128                                 Declarator *D) {
129   assert(Tok.is(tok::kw___attribute) && "Not a GNU attribute list!");
130 
131   while (Tok.is(tok::kw___attribute)) {
132     ConsumeToken();
133     if (ExpectAndConsume(tok::l_paren, diag::err_expected_lparen_after,
134                          "attribute")) {
135       SkipUntil(tok::r_paren, StopAtSemi); // skip until ) or ;
136       return;
137     }
138     if (ExpectAndConsume(tok::l_paren, diag::err_expected_lparen_after, "(")) {
139       SkipUntil(tok::r_paren, StopAtSemi); // skip until ) or ;
140       return;
141     }
142     // Parse the attribute-list. e.g. __attribute__(( weak, alias("__f") ))
143     while (true) {
144       // Allow empty/non-empty attributes. ((__vector_size__(16),,,,))
145       if (TryConsumeToken(tok::comma))
146         continue;
147 
148       // Expect an identifier or declaration specifier (const, int, etc.)
149       if (Tok.isAnnotation())
150         break;
151       IdentifierInfo *AttrName = Tok.getIdentifierInfo();
152       if (!AttrName)
153         break;
154 
155       SourceLocation AttrNameLoc = ConsumeToken();
156 
157       if (Tok.isNot(tok::l_paren)) {
158         attrs.addNew(AttrName, AttrNameLoc, nullptr, AttrNameLoc, nullptr, 0,
159                      AttributeList::AS_GNU);
160         continue;
161       }
162 
163       // Handle "parameterized" attributes
164       if (!LateAttrs || !isAttributeLateParsed(*AttrName)) {
165         ParseGNUAttributeArgs(AttrName, AttrNameLoc, attrs, endLoc, nullptr,
166                               SourceLocation(), AttributeList::AS_GNU, D);
167         continue;
168       }
169 
170       // Handle attributes with arguments that require late parsing.
171       LateParsedAttribute *LA =
172           new LateParsedAttribute(this, *AttrName, AttrNameLoc);
173       LateAttrs->push_back(LA);
174 
175       // Attributes in a class are parsed at the end of the class, along
176       // with other late-parsed declarations.
177       if (!ClassStack.empty() && !LateAttrs->parseSoon())
178         getCurrentClass().LateParsedDeclarations.push_back(LA);
179 
180       // consume everything up to and including the matching right parens
181       ConsumeAndStoreUntil(tok::r_paren, LA->Toks, true, false);
182 
183       Token Eof;
184       Eof.startToken();
185       Eof.setLocation(Tok.getLocation());
186       LA->Toks.push_back(Eof);
187     }
188 
189     if (ExpectAndConsume(tok::r_paren))
190       SkipUntil(tok::r_paren, StopAtSemi);
191     SourceLocation Loc = Tok.getLocation();
192     if (ExpectAndConsume(tok::r_paren))
193       SkipUntil(tok::r_paren, StopAtSemi);
194     if (endLoc)
195       *endLoc = Loc;
196   }
197 }
198 
199 /// \brief Normalizes an attribute name by dropping prefixed and suffixed __.
200 static StringRef normalizeAttrName(StringRef Name) {
201   if (Name.size() >= 4 && Name.startswith("__") && Name.endswith("__"))
202     Name = Name.drop_front(2).drop_back(2);
203   return Name;
204 }
205 
206 /// \brief Determine whether the given attribute has an identifier argument.
207 static bool attributeHasIdentifierArg(const IdentifierInfo &II) {
208 #define CLANG_ATTR_IDENTIFIER_ARG_LIST
209   return llvm::StringSwitch<bool>(normalizeAttrName(II.getName()))
210 #include "clang/Parse/AttrParserStringSwitches.inc"
211            .Default(false);
212 #undef CLANG_ATTR_IDENTIFIER_ARG_LIST
213 }
214 
215 /// \brief Determine whether the given attribute parses a type argument.
216 static bool attributeIsTypeArgAttr(const IdentifierInfo &II) {
217 #define CLANG_ATTR_TYPE_ARG_LIST
218   return llvm::StringSwitch<bool>(normalizeAttrName(II.getName()))
219 #include "clang/Parse/AttrParserStringSwitches.inc"
220            .Default(false);
221 #undef CLANG_ATTR_TYPE_ARG_LIST
222 }
223 
224 /// \brief Determine whether the given attribute requires parsing its arguments
225 /// in an unevaluated context or not.
226 static bool attributeParsedArgsUnevaluated(const IdentifierInfo &II) {
227 #define CLANG_ATTR_ARG_CONTEXT_LIST
228   return llvm::StringSwitch<bool>(normalizeAttrName(II.getName()))
229 #include "clang/Parse/AttrParserStringSwitches.inc"
230            .Default(false);
231 #undef CLANG_ATTR_ARG_CONTEXT_LIST
232 }
233 
234 IdentifierLoc *Parser::ParseIdentifierLoc() {
235   assert(Tok.is(tok::identifier) && "expected an identifier");
236   IdentifierLoc *IL = IdentifierLoc::create(Actions.Context,
237                                             Tok.getLocation(),
238                                             Tok.getIdentifierInfo());
239   ConsumeToken();
240   return IL;
241 }
242 
243 void Parser::ParseAttributeWithTypeArg(IdentifierInfo &AttrName,
244                                        SourceLocation AttrNameLoc,
245                                        ParsedAttributes &Attrs,
246                                        SourceLocation *EndLoc,
247                                        IdentifierInfo *ScopeName,
248                                        SourceLocation ScopeLoc,
249                                        AttributeList::Syntax Syntax) {
250   BalancedDelimiterTracker Parens(*this, tok::l_paren);
251   Parens.consumeOpen();
252 
253   TypeResult T;
254   if (Tok.isNot(tok::r_paren))
255     T = ParseTypeName();
256 
257   if (Parens.consumeClose())
258     return;
259 
260   if (T.isInvalid())
261     return;
262 
263   if (T.isUsable())
264     Attrs.addNewTypeAttr(&AttrName,
265                          SourceRange(AttrNameLoc, Parens.getCloseLocation()),
266                          ScopeName, ScopeLoc, T.get(), Syntax);
267   else
268     Attrs.addNew(&AttrName, SourceRange(AttrNameLoc, Parens.getCloseLocation()),
269                  ScopeName, ScopeLoc, nullptr, 0, Syntax);
270 }
271 
272 unsigned Parser::ParseAttributeArgsCommon(
273     IdentifierInfo *AttrName, SourceLocation AttrNameLoc,
274     ParsedAttributes &Attrs, SourceLocation *EndLoc, IdentifierInfo *ScopeName,
275     SourceLocation ScopeLoc, AttributeList::Syntax Syntax) {
276   // Ignore the left paren location for now.
277   ConsumeParen();
278 
279   ArgsVector ArgExprs;
280   if (Tok.is(tok::identifier)) {
281     // If this attribute wants an 'identifier' argument, make it so.
282     bool IsIdentifierArg = attributeHasIdentifierArg(*AttrName);
283     AttributeList::Kind AttrKind =
284         AttributeList::getKind(AttrName, ScopeName, Syntax);
285 
286     // If we don't know how to parse this attribute, but this is the only
287     // token in this argument, assume it's meant to be an identifier.
288     if (AttrKind == AttributeList::UnknownAttribute ||
289         AttrKind == AttributeList::IgnoredAttribute) {
290       const Token &Next = NextToken();
291       IsIdentifierArg = Next.isOneOf(tok::r_paren, tok::comma);
292     }
293 
294     if (IsIdentifierArg)
295       ArgExprs.push_back(ParseIdentifierLoc());
296   }
297 
298   if (!ArgExprs.empty() ? Tok.is(tok::comma) : Tok.isNot(tok::r_paren)) {
299     // Eat the comma.
300     if (!ArgExprs.empty())
301       ConsumeToken();
302 
303     // Parse the non-empty comma-separated list of expressions.
304     do {
305       bool ShouldEnter = attributeParsedArgsUnevaluated(*AttrName);
306       EnterExpressionEvaluationContext Unevaluated(
307           Actions, Sema::Unevaluated, /*LambdaContextDecl=*/nullptr,
308           /*IsDecltype=*/false, ShouldEnter);
309 
310       ExprResult ArgExpr(
311           Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression()));
312       if (ArgExpr.isInvalid()) {
313         SkipUntil(tok::r_paren, StopAtSemi);
314         return 0;
315       }
316       ArgExprs.push_back(ArgExpr.get());
317       // Eat the comma, move to the next argument
318     } while (TryConsumeToken(tok::comma));
319   }
320 
321   SourceLocation RParen = Tok.getLocation();
322   if (!ExpectAndConsume(tok::r_paren)) {
323     SourceLocation AttrLoc = ScopeLoc.isValid() ? ScopeLoc : AttrNameLoc;
324     Attrs.addNew(AttrName, SourceRange(AttrLoc, RParen), ScopeName, ScopeLoc,
325                  ArgExprs.data(), ArgExprs.size(), Syntax);
326   }
327 
328   if (EndLoc)
329     *EndLoc = RParen;
330 
331   return static_cast<unsigned>(ArgExprs.size());
332 }
333 
334 /// Parse the arguments to a parameterized GNU attribute or
335 /// a C++11 attribute in "gnu" namespace.
336 void Parser::ParseGNUAttributeArgs(IdentifierInfo *AttrName,
337                                    SourceLocation AttrNameLoc,
338                                    ParsedAttributes &Attrs,
339                                    SourceLocation *EndLoc,
340                                    IdentifierInfo *ScopeName,
341                                    SourceLocation ScopeLoc,
342                                    AttributeList::Syntax Syntax,
343                                    Declarator *D) {
344 
345   assert(Tok.is(tok::l_paren) && "Attribute arg list not starting with '('");
346 
347   AttributeList::Kind AttrKind =
348       AttributeList::getKind(AttrName, ScopeName, Syntax);
349 
350   if (AttrKind == AttributeList::AT_Availability) {
351     ParseAvailabilityAttribute(*AttrName, AttrNameLoc, Attrs, EndLoc, ScopeName,
352                                ScopeLoc, Syntax);
353     return;
354   } else if (AttrKind == AttributeList::AT_ObjCBridgeRelated) {
355     ParseObjCBridgeRelatedAttribute(*AttrName, AttrNameLoc, Attrs, EndLoc,
356                                     ScopeName, ScopeLoc, Syntax);
357     return;
358   } else if (AttrKind == AttributeList::AT_TypeTagForDatatype) {
359     ParseTypeTagForDatatypeAttribute(*AttrName, AttrNameLoc, Attrs, EndLoc,
360                                      ScopeName, ScopeLoc, Syntax);
361     return;
362   } else if (attributeIsTypeArgAttr(*AttrName)) {
363     ParseAttributeWithTypeArg(*AttrName, AttrNameLoc, Attrs, EndLoc, ScopeName,
364                               ScopeLoc, Syntax);
365     return;
366   }
367 
368   // These may refer to the function arguments, but need to be parsed early to
369   // participate in determining whether it's a redeclaration.
370   llvm::Optional<ParseScope> PrototypeScope;
371   if (normalizeAttrName(AttrName->getName()) == "enable_if" &&
372       D && D->isFunctionDeclarator()) {
373     DeclaratorChunk::FunctionTypeInfo FTI = D->getFunctionTypeInfo();
374     PrototypeScope.emplace(this, Scope::FunctionPrototypeScope |
375                                      Scope::FunctionDeclarationScope |
376                                      Scope::DeclScope);
377     for (unsigned i = 0; i != FTI.NumParams; ++i) {
378       ParmVarDecl *Param = cast<ParmVarDecl>(FTI.Params[i].Param);
379       Actions.ActOnReenterCXXMethodParameter(getCurScope(), Param);
380     }
381   }
382 
383   ParseAttributeArgsCommon(AttrName, AttrNameLoc, Attrs, EndLoc, ScopeName,
384                            ScopeLoc, Syntax);
385 }
386 
387 bool Parser::ParseMicrosoftDeclSpecArgs(IdentifierInfo *AttrName,
388                                         SourceLocation AttrNameLoc,
389                                         ParsedAttributes &Attrs) {
390   // If the attribute isn't known, we will not attempt to parse any
391   // arguments.
392   if (!hasAttribute(AttrSyntax::Declspec, nullptr, AttrName,
393                     getTargetInfo(), getLangOpts())) {
394     // Eat the left paren, then skip to the ending right paren.
395     ConsumeParen();
396     SkipUntil(tok::r_paren);
397     return false;
398   }
399 
400   SourceLocation OpenParenLoc = Tok.getLocation();
401 
402   if (AttrName->getName() == "property") {
403     // The property declspec is more complex in that it can take one or two
404     // assignment expressions as a parameter, but the lhs of the assignment
405     // must be named get or put.
406 
407     BalancedDelimiterTracker T(*this, tok::l_paren);
408     T.expectAndConsume(diag::err_expected_lparen_after,
409                        AttrName->getNameStart(), tok::r_paren);
410 
411     enum AccessorKind {
412       AK_Invalid = -1,
413       AK_Put = 0,
414       AK_Get = 1 // indices into AccessorNames
415     };
416     IdentifierInfo *AccessorNames[] = {nullptr, nullptr};
417     bool HasInvalidAccessor = false;
418 
419     // Parse the accessor specifications.
420     while (true) {
421       // Stop if this doesn't look like an accessor spec.
422       if (!Tok.is(tok::identifier)) {
423         // If the user wrote a completely empty list, use a special diagnostic.
424         if (Tok.is(tok::r_paren) && !HasInvalidAccessor &&
425             AccessorNames[AK_Put] == nullptr &&
426             AccessorNames[AK_Get] == nullptr) {
427           Diag(AttrNameLoc, diag::err_ms_property_no_getter_or_putter);
428           break;
429         }
430 
431         Diag(Tok.getLocation(), diag::err_ms_property_unknown_accessor);
432         break;
433       }
434 
435       AccessorKind Kind;
436       SourceLocation KindLoc = Tok.getLocation();
437       StringRef KindStr = Tok.getIdentifierInfo()->getName();
438       if (KindStr == "get") {
439         Kind = AK_Get;
440       } else if (KindStr == "put") {
441         Kind = AK_Put;
442 
443         // Recover from the common mistake of using 'set' instead of 'put'.
444       } else if (KindStr == "set") {
445         Diag(KindLoc, diag::err_ms_property_has_set_accessor)
446             << FixItHint::CreateReplacement(KindLoc, "put");
447         Kind = AK_Put;
448 
449         // Handle the mistake of forgetting the accessor kind by skipping
450         // this accessor.
451       } else if (NextToken().is(tok::comma) || NextToken().is(tok::r_paren)) {
452         Diag(KindLoc, diag::err_ms_property_missing_accessor_kind);
453         ConsumeToken();
454         HasInvalidAccessor = true;
455         goto next_property_accessor;
456 
457         // Otherwise, complain about the unknown accessor kind.
458       } else {
459         Diag(KindLoc, diag::err_ms_property_unknown_accessor);
460         HasInvalidAccessor = true;
461         Kind = AK_Invalid;
462 
463         // Try to keep parsing unless it doesn't look like an accessor spec.
464         if (!NextToken().is(tok::equal))
465           break;
466       }
467 
468       // Consume the identifier.
469       ConsumeToken();
470 
471       // Consume the '='.
472       if (!TryConsumeToken(tok::equal)) {
473         Diag(Tok.getLocation(), diag::err_ms_property_expected_equal)
474             << KindStr;
475         break;
476       }
477 
478       // Expect the method name.
479       if (!Tok.is(tok::identifier)) {
480         Diag(Tok.getLocation(), diag::err_ms_property_expected_accessor_name);
481         break;
482       }
483 
484       if (Kind == AK_Invalid) {
485         // Just drop invalid accessors.
486       } else if (AccessorNames[Kind] != nullptr) {
487         // Complain about the repeated accessor, ignore it, and keep parsing.
488         Diag(KindLoc, diag::err_ms_property_duplicate_accessor) << KindStr;
489       } else {
490         AccessorNames[Kind] = Tok.getIdentifierInfo();
491       }
492       ConsumeToken();
493 
494     next_property_accessor:
495       // Keep processing accessors until we run out.
496       if (TryConsumeToken(tok::comma))
497         continue;
498 
499       // If we run into the ')', stop without consuming it.
500       if (Tok.is(tok::r_paren))
501         break;
502 
503       Diag(Tok.getLocation(), diag::err_ms_property_expected_comma_or_rparen);
504       break;
505     }
506 
507     // Only add the property attribute if it was well-formed.
508     if (!HasInvalidAccessor)
509       Attrs.addNewPropertyAttr(AttrName, AttrNameLoc, nullptr, SourceLocation(),
510                                AccessorNames[AK_Get], AccessorNames[AK_Put],
511                                AttributeList::AS_Declspec);
512     T.skipToEnd();
513     return !HasInvalidAccessor;
514   }
515 
516   unsigned NumArgs =
517       ParseAttributeArgsCommon(AttrName, AttrNameLoc, Attrs, nullptr, nullptr,
518                                SourceLocation(), AttributeList::AS_Declspec);
519 
520   // If this attribute's args were parsed, and it was expected to have
521   // arguments but none were provided, emit a diagnostic.
522   const AttributeList *Attr = Attrs.getList();
523   if (Attr && Attr->getMaxArgs() && !NumArgs) {
524     Diag(OpenParenLoc, diag::err_attribute_requires_arguments) << AttrName;
525     return false;
526   }
527   return true;
528 }
529 
530 /// [MS] decl-specifier:
531 ///             __declspec ( extended-decl-modifier-seq )
532 ///
533 /// [MS] extended-decl-modifier-seq:
534 ///             extended-decl-modifier[opt]
535 ///             extended-decl-modifier extended-decl-modifier-seq
536 void Parser::ParseMicrosoftDeclSpecs(ParsedAttributes &Attrs,
537                                      SourceLocation *End) {
538   assert(getLangOpts().DeclSpecKeyword && "__declspec keyword is not enabled");
539   assert(Tok.is(tok::kw___declspec) && "Not a declspec!");
540 
541   while (Tok.is(tok::kw___declspec)) {
542     ConsumeToken();
543     BalancedDelimiterTracker T(*this, tok::l_paren);
544     if (T.expectAndConsume(diag::err_expected_lparen_after, "__declspec",
545                            tok::r_paren))
546       return;
547 
548     // An empty declspec is perfectly legal and should not warn.  Additionally,
549     // you can specify multiple attributes per declspec.
550     while (Tok.isNot(tok::r_paren)) {
551       // Attribute not present.
552       if (TryConsumeToken(tok::comma))
553         continue;
554 
555       // We expect either a well-known identifier or a generic string.  Anything
556       // else is a malformed declspec.
557       bool IsString = Tok.getKind() == tok::string_literal;
558       if (!IsString && Tok.getKind() != tok::identifier &&
559           Tok.getKind() != tok::kw_restrict) {
560         Diag(Tok, diag::err_ms_declspec_type);
561         T.skipToEnd();
562         return;
563       }
564 
565       IdentifierInfo *AttrName;
566       SourceLocation AttrNameLoc;
567       if (IsString) {
568         SmallString<8> StrBuffer;
569         bool Invalid = false;
570         StringRef Str = PP.getSpelling(Tok, StrBuffer, &Invalid);
571         if (Invalid) {
572           T.skipToEnd();
573           return;
574         }
575         AttrName = PP.getIdentifierInfo(Str);
576         AttrNameLoc = ConsumeStringToken();
577       } else {
578         AttrName = Tok.getIdentifierInfo();
579         AttrNameLoc = ConsumeToken();
580       }
581 
582       bool AttrHandled = false;
583 
584       // Parse attribute arguments.
585       if (Tok.is(tok::l_paren))
586         AttrHandled = ParseMicrosoftDeclSpecArgs(AttrName, AttrNameLoc, Attrs);
587       else if (AttrName->getName() == "property")
588         // The property attribute must have an argument list.
589         Diag(Tok.getLocation(), diag::err_expected_lparen_after)
590             << AttrName->getName();
591 
592       if (!AttrHandled)
593         Attrs.addNew(AttrName, AttrNameLoc, nullptr, AttrNameLoc, nullptr, 0,
594                      AttributeList::AS_Declspec);
595     }
596     T.consumeClose();
597     if (End)
598       *End = T.getCloseLocation();
599   }
600 }
601 
602 void Parser::ParseMicrosoftTypeAttributes(ParsedAttributes &attrs) {
603   // Treat these like attributes
604   while (true) {
605     switch (Tok.getKind()) {
606     case tok::kw___fastcall:
607     case tok::kw___stdcall:
608     case tok::kw___thiscall:
609     case tok::kw___regcall:
610     case tok::kw___cdecl:
611     case tok::kw___vectorcall:
612     case tok::kw___ptr64:
613     case tok::kw___w64:
614     case tok::kw___ptr32:
615     case tok::kw___sptr:
616     case tok::kw___uptr: {
617       IdentifierInfo *AttrName = Tok.getIdentifierInfo();
618       SourceLocation AttrNameLoc = ConsumeToken();
619       attrs.addNew(AttrName, AttrNameLoc, nullptr, AttrNameLoc, nullptr, 0,
620                    AttributeList::AS_Keyword);
621       break;
622     }
623     default:
624       return;
625     }
626   }
627 }
628 
629 void Parser::DiagnoseAndSkipExtendedMicrosoftTypeAttributes() {
630   SourceLocation StartLoc = Tok.getLocation();
631   SourceLocation EndLoc = SkipExtendedMicrosoftTypeAttributes();
632 
633   if (EndLoc.isValid()) {
634     SourceRange Range(StartLoc, EndLoc);
635     Diag(StartLoc, diag::warn_microsoft_qualifiers_ignored) << Range;
636   }
637 }
638 
639 SourceLocation Parser::SkipExtendedMicrosoftTypeAttributes() {
640   SourceLocation EndLoc;
641 
642   while (true) {
643     switch (Tok.getKind()) {
644     case tok::kw_const:
645     case tok::kw_volatile:
646     case tok::kw___fastcall:
647     case tok::kw___stdcall:
648     case tok::kw___thiscall:
649     case tok::kw___cdecl:
650     case tok::kw___vectorcall:
651     case tok::kw___ptr32:
652     case tok::kw___ptr64:
653     case tok::kw___w64:
654     case tok::kw___unaligned:
655     case tok::kw___sptr:
656     case tok::kw___uptr:
657       EndLoc = ConsumeToken();
658       break;
659     default:
660       return EndLoc;
661     }
662   }
663 }
664 
665 void Parser::ParseBorlandTypeAttributes(ParsedAttributes &attrs) {
666   // Treat these like attributes
667   while (Tok.is(tok::kw___pascal)) {
668     IdentifierInfo *AttrName = Tok.getIdentifierInfo();
669     SourceLocation AttrNameLoc = ConsumeToken();
670     attrs.addNew(AttrName, AttrNameLoc, nullptr, AttrNameLoc, nullptr, 0,
671                  AttributeList::AS_Keyword);
672   }
673 }
674 
675 void Parser::ParseOpenCLKernelAttributes(ParsedAttributes &attrs) {
676   // Treat these like attributes
677   while (Tok.is(tok::kw___kernel)) {
678     IdentifierInfo *AttrName = Tok.getIdentifierInfo();
679     SourceLocation AttrNameLoc = ConsumeToken();
680     attrs.addNew(AttrName, AttrNameLoc, nullptr, AttrNameLoc, nullptr, 0,
681                  AttributeList::AS_Keyword);
682   }
683 }
684 
685 void Parser::ParseOpenCLQualifiers(ParsedAttributes &Attrs) {
686   IdentifierInfo *AttrName = Tok.getIdentifierInfo();
687   SourceLocation AttrNameLoc = Tok.getLocation();
688   Attrs.addNew(AttrName, AttrNameLoc, nullptr, AttrNameLoc, nullptr, 0,
689                AttributeList::AS_Keyword);
690 }
691 
692 void Parser::ParseNullabilityTypeSpecifiers(ParsedAttributes &attrs) {
693   // Treat these like attributes, even though they're type specifiers.
694   while (true) {
695     switch (Tok.getKind()) {
696     case tok::kw__Nonnull:
697     case tok::kw__Nullable:
698     case tok::kw__Null_unspecified: {
699       IdentifierInfo *AttrName = Tok.getIdentifierInfo();
700       SourceLocation AttrNameLoc = ConsumeToken();
701       if (!getLangOpts().ObjC1)
702         Diag(AttrNameLoc, diag::ext_nullability)
703           << AttrName;
704       attrs.addNew(AttrName, AttrNameLoc, nullptr, AttrNameLoc, nullptr, 0,
705                    AttributeList::AS_Keyword);
706       break;
707     }
708     default:
709       return;
710     }
711   }
712 }
713 
714 static bool VersionNumberSeparator(const char Separator) {
715   return (Separator == '.' || Separator == '_');
716 }
717 
718 /// \brief Parse a version number.
719 ///
720 /// version:
721 ///   simple-integer
722 ///   simple-integer ',' simple-integer
723 ///   simple-integer ',' simple-integer ',' simple-integer
724 VersionTuple Parser::ParseVersionTuple(SourceRange &Range) {
725   Range = SourceRange(Tok.getLocation(), Tok.getEndLoc());
726 
727   if (!Tok.is(tok::numeric_constant)) {
728     Diag(Tok, diag::err_expected_version);
729     SkipUntil(tok::comma, tok::r_paren,
730               StopAtSemi | StopBeforeMatch | StopAtCodeCompletion);
731     return VersionTuple();
732   }
733 
734   // Parse the major (and possibly minor and subminor) versions, which
735   // are stored in the numeric constant. We utilize a quirk of the
736   // lexer, which is that it handles something like 1.2.3 as a single
737   // numeric constant, rather than two separate tokens.
738   SmallString<512> Buffer;
739   Buffer.resize(Tok.getLength()+1);
740   const char *ThisTokBegin = &Buffer[0];
741 
742   // Get the spelling of the token, which eliminates trigraphs, etc.
743   bool Invalid = false;
744   unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin, &Invalid);
745   if (Invalid)
746     return VersionTuple();
747 
748   // Parse the major version.
749   unsigned AfterMajor = 0;
750   unsigned Major = 0;
751   while (AfterMajor < ActualLength && isDigit(ThisTokBegin[AfterMajor])) {
752     Major = Major * 10 + ThisTokBegin[AfterMajor] - '0';
753     ++AfterMajor;
754   }
755 
756   if (AfterMajor == 0) {
757     Diag(Tok, diag::err_expected_version);
758     SkipUntil(tok::comma, tok::r_paren,
759               StopAtSemi | StopBeforeMatch | StopAtCodeCompletion);
760     return VersionTuple();
761   }
762 
763   if (AfterMajor == ActualLength) {
764     ConsumeToken();
765 
766     // We only had a single version component.
767     if (Major == 0) {
768       Diag(Tok, diag::err_zero_version);
769       return VersionTuple();
770     }
771 
772     return VersionTuple(Major);
773   }
774 
775   const char AfterMajorSeparator = ThisTokBegin[AfterMajor];
776   if (!VersionNumberSeparator(AfterMajorSeparator)
777       || (AfterMajor + 1 == ActualLength)) {
778     Diag(Tok, diag::err_expected_version);
779     SkipUntil(tok::comma, tok::r_paren,
780               StopAtSemi | StopBeforeMatch | StopAtCodeCompletion);
781     return VersionTuple();
782   }
783 
784   // Parse the minor version.
785   unsigned AfterMinor = AfterMajor + 1;
786   unsigned Minor = 0;
787   while (AfterMinor < ActualLength && isDigit(ThisTokBegin[AfterMinor])) {
788     Minor = Minor * 10 + ThisTokBegin[AfterMinor] - '0';
789     ++AfterMinor;
790   }
791 
792   if (AfterMinor == ActualLength) {
793     ConsumeToken();
794 
795     // We had major.minor.
796     if (Major == 0 && Minor == 0) {
797       Diag(Tok, diag::err_zero_version);
798       return VersionTuple();
799     }
800 
801     return VersionTuple(Major, Minor, (AfterMajorSeparator == '_'));
802   }
803 
804   const char AfterMinorSeparator = ThisTokBegin[AfterMinor];
805   // If what follows is not a '.' or '_', we have a problem.
806   if (!VersionNumberSeparator(AfterMinorSeparator)) {
807     Diag(Tok, diag::err_expected_version);
808     SkipUntil(tok::comma, tok::r_paren,
809               StopAtSemi | StopBeforeMatch | StopAtCodeCompletion);
810     return VersionTuple();
811   }
812 
813   // Warn if separators, be it '.' or '_', do not match.
814   if (AfterMajorSeparator != AfterMinorSeparator)
815     Diag(Tok, diag::warn_expected_consistent_version_separator);
816 
817   // Parse the subminor version.
818   unsigned AfterSubminor = AfterMinor + 1;
819   unsigned Subminor = 0;
820   while (AfterSubminor < ActualLength && isDigit(ThisTokBegin[AfterSubminor])) {
821     Subminor = Subminor * 10 + ThisTokBegin[AfterSubminor] - '0';
822     ++AfterSubminor;
823   }
824 
825   if (AfterSubminor != ActualLength) {
826     Diag(Tok, diag::err_expected_version);
827     SkipUntil(tok::comma, tok::r_paren,
828               StopAtSemi | StopBeforeMatch | StopAtCodeCompletion);
829     return VersionTuple();
830   }
831   ConsumeToken();
832   return VersionTuple(Major, Minor, Subminor, (AfterMajorSeparator == '_'));
833 }
834 
835 /// \brief Parse the contents of the "availability" attribute.
836 ///
837 /// availability-attribute:
838 ///   'availability' '(' platform ',' opt-strict version-arg-list,
839 ///                      opt-replacement, opt-message')'
840 ///
841 /// platform:
842 ///   identifier
843 ///
844 /// opt-strict:
845 ///   'strict' ','
846 ///
847 /// version-arg-list:
848 ///   version-arg
849 ///   version-arg ',' version-arg-list
850 ///
851 /// version-arg:
852 ///   'introduced' '=' version
853 ///   'deprecated' '=' version
854 ///   'obsoleted' = version
855 ///   'unavailable'
856 /// opt-replacement:
857 ///   'replacement' '=' <string>
858 /// opt-message:
859 ///   'message' '=' <string>
860 void Parser::ParseAvailabilityAttribute(IdentifierInfo &Availability,
861                                         SourceLocation AvailabilityLoc,
862                                         ParsedAttributes &attrs,
863                                         SourceLocation *endLoc,
864                                         IdentifierInfo *ScopeName,
865                                         SourceLocation ScopeLoc,
866                                         AttributeList::Syntax Syntax) {
867   enum { Introduced, Deprecated, Obsoleted, Unknown };
868   AvailabilityChange Changes[Unknown];
869   ExprResult MessageExpr, ReplacementExpr;
870 
871   // Opening '('.
872   BalancedDelimiterTracker T(*this, tok::l_paren);
873   if (T.consumeOpen()) {
874     Diag(Tok, diag::err_expected) << tok::l_paren;
875     return;
876   }
877 
878   // Parse the platform name.
879   if (Tok.isNot(tok::identifier)) {
880     Diag(Tok, diag::err_availability_expected_platform);
881     SkipUntil(tok::r_paren, StopAtSemi);
882     return;
883   }
884   IdentifierLoc *Platform = ParseIdentifierLoc();
885   // Canonicalize platform name from "macosx" to "macos".
886   if (Platform->Ident && Platform->Ident->getName() == "macosx")
887     Platform->Ident = PP.getIdentifierInfo("macos");
888   // Canonicalize platform name from "macosx_app_extension" to
889   // "macos_app_extension".
890   if (Platform->Ident && Platform->Ident->getName() == "macosx_app_extension")
891     Platform->Ident = PP.getIdentifierInfo("macos_app_extension");
892 
893   // Parse the ',' following the platform name.
894   if (ExpectAndConsume(tok::comma)) {
895     SkipUntil(tok::r_paren, StopAtSemi);
896     return;
897   }
898 
899   // If we haven't grabbed the pointers for the identifiers
900   // "introduced", "deprecated", and "obsoleted", do so now.
901   if (!Ident_introduced) {
902     Ident_introduced = PP.getIdentifierInfo("introduced");
903     Ident_deprecated = PP.getIdentifierInfo("deprecated");
904     Ident_obsoleted = PP.getIdentifierInfo("obsoleted");
905     Ident_unavailable = PP.getIdentifierInfo("unavailable");
906     Ident_message = PP.getIdentifierInfo("message");
907     Ident_strict = PP.getIdentifierInfo("strict");
908     Ident_replacement = PP.getIdentifierInfo("replacement");
909   }
910 
911   // Parse the optional "strict", the optional "replacement" and the set of
912   // introductions/deprecations/removals.
913   SourceLocation UnavailableLoc, StrictLoc;
914   do {
915     if (Tok.isNot(tok::identifier)) {
916       Diag(Tok, diag::err_availability_expected_change);
917       SkipUntil(tok::r_paren, StopAtSemi);
918       return;
919     }
920     IdentifierInfo *Keyword = Tok.getIdentifierInfo();
921     SourceLocation KeywordLoc = ConsumeToken();
922 
923     if (Keyword == Ident_strict) {
924       if (StrictLoc.isValid()) {
925         Diag(KeywordLoc, diag::err_availability_redundant)
926           << Keyword << SourceRange(StrictLoc);
927       }
928       StrictLoc = KeywordLoc;
929       continue;
930     }
931 
932     if (Keyword == Ident_unavailable) {
933       if (UnavailableLoc.isValid()) {
934         Diag(KeywordLoc, diag::err_availability_redundant)
935           << Keyword << SourceRange(UnavailableLoc);
936       }
937       UnavailableLoc = KeywordLoc;
938       continue;
939     }
940 
941     if (Tok.isNot(tok::equal)) {
942       Diag(Tok, diag::err_expected_after) << Keyword << tok::equal;
943       SkipUntil(tok::r_paren, StopAtSemi);
944       return;
945     }
946     ConsumeToken();
947     if (Keyword == Ident_message || Keyword == Ident_replacement) {
948       if (Tok.isNot(tok::string_literal)) {
949         Diag(Tok, diag::err_expected_string_literal)
950           << /*Source='availability attribute'*/2;
951         SkipUntil(tok::r_paren, StopAtSemi);
952         return;
953       }
954       if (Keyword == Ident_message)
955         MessageExpr = ParseStringLiteralExpression();
956       else
957         ReplacementExpr = ParseStringLiteralExpression();
958       // Also reject wide string literals.
959       if (StringLiteral *MessageStringLiteral =
960               cast_or_null<StringLiteral>(MessageExpr.get())) {
961         if (MessageStringLiteral->getCharByteWidth() != 1) {
962           Diag(MessageStringLiteral->getSourceRange().getBegin(),
963                diag::err_expected_string_literal)
964             << /*Source='availability attribute'*/ 2;
965           SkipUntil(tok::r_paren, StopAtSemi);
966           return;
967         }
968       }
969       if (Keyword == Ident_message)
970         break;
971       else
972         continue;
973     }
974 
975     // Special handling of 'NA' only when applied to introduced or
976     // deprecated.
977     if ((Keyword == Ident_introduced || Keyword == Ident_deprecated) &&
978         Tok.is(tok::identifier)) {
979       IdentifierInfo *NA = Tok.getIdentifierInfo();
980       if (NA->getName() == "NA") {
981         ConsumeToken();
982         if (Keyword == Ident_introduced)
983           UnavailableLoc = KeywordLoc;
984         continue;
985       }
986     }
987 
988     SourceRange VersionRange;
989     VersionTuple Version = ParseVersionTuple(VersionRange);
990 
991     if (Version.empty()) {
992       SkipUntil(tok::r_paren, StopAtSemi);
993       return;
994     }
995 
996     unsigned Index;
997     if (Keyword == Ident_introduced)
998       Index = Introduced;
999     else if (Keyword == Ident_deprecated)
1000       Index = Deprecated;
1001     else if (Keyword == Ident_obsoleted)
1002       Index = Obsoleted;
1003     else
1004       Index = Unknown;
1005 
1006     if (Index < Unknown) {
1007       if (!Changes[Index].KeywordLoc.isInvalid()) {
1008         Diag(KeywordLoc, diag::err_availability_redundant)
1009           << Keyword
1010           << SourceRange(Changes[Index].KeywordLoc,
1011                          Changes[Index].VersionRange.getEnd());
1012       }
1013 
1014       Changes[Index].KeywordLoc = KeywordLoc;
1015       Changes[Index].Version = Version;
1016       Changes[Index].VersionRange = VersionRange;
1017     } else {
1018       Diag(KeywordLoc, diag::err_availability_unknown_change)
1019         << Keyword << VersionRange;
1020     }
1021 
1022   } while (TryConsumeToken(tok::comma));
1023 
1024   // Closing ')'.
1025   if (T.consumeClose())
1026     return;
1027 
1028   if (endLoc)
1029     *endLoc = T.getCloseLocation();
1030 
1031   // The 'unavailable' availability cannot be combined with any other
1032   // availability changes. Make sure that hasn't happened.
1033   if (UnavailableLoc.isValid()) {
1034     bool Complained = false;
1035     for (unsigned Index = Introduced; Index != Unknown; ++Index) {
1036       if (Changes[Index].KeywordLoc.isValid()) {
1037         if (!Complained) {
1038           Diag(UnavailableLoc, diag::warn_availability_and_unavailable)
1039             << SourceRange(Changes[Index].KeywordLoc,
1040                            Changes[Index].VersionRange.getEnd());
1041           Complained = true;
1042         }
1043 
1044         // Clear out the availability.
1045         Changes[Index] = AvailabilityChange();
1046       }
1047     }
1048   }
1049 
1050   // Record this attribute
1051   attrs.addNew(&Availability,
1052                SourceRange(AvailabilityLoc, T.getCloseLocation()),
1053                ScopeName, ScopeLoc,
1054                Platform,
1055                Changes[Introduced],
1056                Changes[Deprecated],
1057                Changes[Obsoleted],
1058                UnavailableLoc, MessageExpr.get(),
1059                Syntax, StrictLoc, ReplacementExpr.get());
1060 }
1061 
1062 /// \brief Parse the contents of the "objc_bridge_related" attribute.
1063 /// objc_bridge_related '(' related_class ',' opt-class_method ',' opt-instance_method ')'
1064 /// related_class:
1065 ///     Identifier
1066 ///
1067 /// opt-class_method:
1068 ///     Identifier: | <empty>
1069 ///
1070 /// opt-instance_method:
1071 ///     Identifier | <empty>
1072 ///
1073 void Parser::ParseObjCBridgeRelatedAttribute(IdentifierInfo &ObjCBridgeRelated,
1074                                 SourceLocation ObjCBridgeRelatedLoc,
1075                                 ParsedAttributes &attrs,
1076                                 SourceLocation *endLoc,
1077                                 IdentifierInfo *ScopeName,
1078                                 SourceLocation ScopeLoc,
1079                                 AttributeList::Syntax Syntax) {
1080   // Opening '('.
1081   BalancedDelimiterTracker T(*this, tok::l_paren);
1082   if (T.consumeOpen()) {
1083     Diag(Tok, diag::err_expected) << tok::l_paren;
1084     return;
1085   }
1086 
1087   // Parse the related class name.
1088   if (Tok.isNot(tok::identifier)) {
1089     Diag(Tok, diag::err_objcbridge_related_expected_related_class);
1090     SkipUntil(tok::r_paren, StopAtSemi);
1091     return;
1092   }
1093   IdentifierLoc *RelatedClass = ParseIdentifierLoc();
1094   if (ExpectAndConsume(tok::comma)) {
1095     SkipUntil(tok::r_paren, StopAtSemi);
1096     return;
1097   }
1098 
1099   // Parse optional class method name.
1100   IdentifierLoc *ClassMethod = nullptr;
1101   if (Tok.is(tok::identifier)) {
1102     ClassMethod = ParseIdentifierLoc();
1103     if (!TryConsumeToken(tok::colon)) {
1104       Diag(Tok, diag::err_objcbridge_related_selector_name);
1105       SkipUntil(tok::r_paren, StopAtSemi);
1106       return;
1107     }
1108   }
1109   if (!TryConsumeToken(tok::comma)) {
1110     if (Tok.is(tok::colon))
1111       Diag(Tok, diag::err_objcbridge_related_selector_name);
1112     else
1113       Diag(Tok, diag::err_expected) << tok::comma;
1114     SkipUntil(tok::r_paren, StopAtSemi);
1115     return;
1116   }
1117 
1118   // Parse optional instance method name.
1119   IdentifierLoc *InstanceMethod = nullptr;
1120   if (Tok.is(tok::identifier))
1121     InstanceMethod = ParseIdentifierLoc();
1122   else if (Tok.isNot(tok::r_paren)) {
1123     Diag(Tok, diag::err_expected) << tok::r_paren;
1124     SkipUntil(tok::r_paren, StopAtSemi);
1125     return;
1126   }
1127 
1128   // Closing ')'.
1129   if (T.consumeClose())
1130     return;
1131 
1132   if (endLoc)
1133     *endLoc = T.getCloseLocation();
1134 
1135   // Record this attribute
1136   attrs.addNew(&ObjCBridgeRelated,
1137                SourceRange(ObjCBridgeRelatedLoc, T.getCloseLocation()),
1138                ScopeName, ScopeLoc,
1139                RelatedClass,
1140                ClassMethod,
1141                InstanceMethod,
1142                Syntax);
1143 }
1144 
1145 // Late Parsed Attributes:
1146 // See other examples of late parsing in lib/Parse/ParseCXXInlineMethods
1147 
1148 void Parser::LateParsedDeclaration::ParseLexedAttributes() {}
1149 
1150 void Parser::LateParsedClass::ParseLexedAttributes() {
1151   Self->ParseLexedAttributes(*Class);
1152 }
1153 
1154 void Parser::LateParsedAttribute::ParseLexedAttributes() {
1155   Self->ParseLexedAttribute(*this, true, false);
1156 }
1157 
1158 /// Wrapper class which calls ParseLexedAttribute, after setting up the
1159 /// scope appropriately.
1160 void Parser::ParseLexedAttributes(ParsingClass &Class) {
1161   // Deal with templates
1162   // FIXME: Test cases to make sure this does the right thing for templates.
1163   bool HasTemplateScope = !Class.TopLevelClass && Class.TemplateScope;
1164   ParseScope ClassTemplateScope(this, Scope::TemplateParamScope,
1165                                 HasTemplateScope);
1166   if (HasTemplateScope)
1167     Actions.ActOnReenterTemplateScope(getCurScope(), Class.TagOrTemplate);
1168 
1169   // Set or update the scope flags.
1170   bool AlreadyHasClassScope = Class.TopLevelClass;
1171   unsigned ScopeFlags = Scope::ClassScope|Scope::DeclScope;
1172   ParseScope ClassScope(this, ScopeFlags, !AlreadyHasClassScope);
1173   ParseScopeFlags ClassScopeFlags(this, ScopeFlags, AlreadyHasClassScope);
1174 
1175   // Enter the scope of nested classes
1176   if (!AlreadyHasClassScope)
1177     Actions.ActOnStartDelayedMemberDeclarations(getCurScope(),
1178                                                 Class.TagOrTemplate);
1179   if (!Class.LateParsedDeclarations.empty()) {
1180     for (unsigned i = 0, ni = Class.LateParsedDeclarations.size(); i < ni; ++i){
1181       Class.LateParsedDeclarations[i]->ParseLexedAttributes();
1182     }
1183   }
1184 
1185   if (!AlreadyHasClassScope)
1186     Actions.ActOnFinishDelayedMemberDeclarations(getCurScope(),
1187                                                  Class.TagOrTemplate);
1188 }
1189 
1190 /// \brief Parse all attributes in LAs, and attach them to Decl D.
1191 void Parser::ParseLexedAttributeList(LateParsedAttrList &LAs, Decl *D,
1192                                      bool EnterScope, bool OnDefinition) {
1193   assert(LAs.parseSoon() &&
1194          "Attribute list should be marked for immediate parsing.");
1195   for (unsigned i = 0, ni = LAs.size(); i < ni; ++i) {
1196     if (D)
1197       LAs[i]->addDecl(D);
1198     ParseLexedAttribute(*LAs[i], EnterScope, OnDefinition);
1199     delete LAs[i];
1200   }
1201   LAs.clear();
1202 }
1203 
1204 /// \brief Finish parsing an attribute for which parsing was delayed.
1205 /// This will be called at the end of parsing a class declaration
1206 /// for each LateParsedAttribute. We consume the saved tokens and
1207 /// create an attribute with the arguments filled in. We add this
1208 /// to the Attribute list for the decl.
1209 void Parser::ParseLexedAttribute(LateParsedAttribute &LA,
1210                                  bool EnterScope, bool OnDefinition) {
1211   // Create a fake EOF so that attribute parsing won't go off the end of the
1212   // attribute.
1213   Token AttrEnd;
1214   AttrEnd.startToken();
1215   AttrEnd.setKind(tok::eof);
1216   AttrEnd.setLocation(Tok.getLocation());
1217   AttrEnd.setEofData(LA.Toks.data());
1218   LA.Toks.push_back(AttrEnd);
1219 
1220   // Append the current token at the end of the new token stream so that it
1221   // doesn't get lost.
1222   LA.Toks.push_back(Tok);
1223   PP.EnterTokenStream(LA.Toks, true);
1224   // Consume the previously pushed token.
1225   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
1226 
1227   ParsedAttributes Attrs(AttrFactory);
1228   SourceLocation endLoc;
1229 
1230   if (LA.Decls.size() > 0) {
1231     Decl *D = LA.Decls[0];
1232     NamedDecl *ND  = dyn_cast<NamedDecl>(D);
1233     RecordDecl *RD = dyn_cast_or_null<RecordDecl>(D->getDeclContext());
1234 
1235     // Allow 'this' within late-parsed attributes.
1236     Sema::CXXThisScopeRAII ThisScope(Actions, RD, /*TypeQuals=*/0,
1237                                      ND && ND->isCXXInstanceMember());
1238 
1239     if (LA.Decls.size() == 1) {
1240       // If the Decl is templatized, add template parameters to scope.
1241       bool HasTemplateScope = EnterScope && D->isTemplateDecl();
1242       ParseScope TempScope(this, Scope::TemplateParamScope, HasTemplateScope);
1243       if (HasTemplateScope)
1244         Actions.ActOnReenterTemplateScope(Actions.CurScope, D);
1245 
1246       // If the Decl is on a function, add function parameters to the scope.
1247       bool HasFunScope = EnterScope && D->isFunctionOrFunctionTemplate();
1248       ParseScope FnScope(this, Scope::FnScope|Scope::DeclScope, HasFunScope);
1249       if (HasFunScope)
1250         Actions.ActOnReenterFunctionContext(Actions.CurScope, D);
1251 
1252       ParseGNUAttributeArgs(&LA.AttrName, LA.AttrNameLoc, Attrs, &endLoc,
1253                             nullptr, SourceLocation(), AttributeList::AS_GNU,
1254                             nullptr);
1255 
1256       if (HasFunScope) {
1257         Actions.ActOnExitFunctionContext();
1258         FnScope.Exit();  // Pop scope, and remove Decls from IdResolver
1259       }
1260       if (HasTemplateScope) {
1261         TempScope.Exit();
1262       }
1263     } else {
1264       // If there are multiple decls, then the decl cannot be within the
1265       // function scope.
1266       ParseGNUAttributeArgs(&LA.AttrName, LA.AttrNameLoc, Attrs, &endLoc,
1267                             nullptr, SourceLocation(), AttributeList::AS_GNU,
1268                             nullptr);
1269     }
1270   } else {
1271     Diag(Tok, diag::warn_attribute_no_decl) << LA.AttrName.getName();
1272   }
1273 
1274   const AttributeList *AL = Attrs.getList();
1275   if (OnDefinition && AL && !AL->isCXX11Attribute() &&
1276       AL->isKnownToGCC())
1277     Diag(Tok, diag::warn_attribute_on_function_definition)
1278       << &LA.AttrName;
1279 
1280   for (unsigned i = 0, ni = LA.Decls.size(); i < ni; ++i)
1281     Actions.ActOnFinishDelayedAttribute(getCurScope(), LA.Decls[i], Attrs);
1282 
1283   // Due to a parsing error, we either went over the cached tokens or
1284   // there are still cached tokens left, so we skip the leftover tokens.
1285   while (Tok.isNot(tok::eof))
1286     ConsumeAnyToken();
1287 
1288   if (Tok.is(tok::eof) && Tok.getEofData() == AttrEnd.getEofData())
1289     ConsumeAnyToken();
1290 }
1291 
1292 void Parser::ParseTypeTagForDatatypeAttribute(IdentifierInfo &AttrName,
1293                                               SourceLocation AttrNameLoc,
1294                                               ParsedAttributes &Attrs,
1295                                               SourceLocation *EndLoc,
1296                                               IdentifierInfo *ScopeName,
1297                                               SourceLocation ScopeLoc,
1298                                               AttributeList::Syntax Syntax) {
1299   assert(Tok.is(tok::l_paren) && "Attribute arg list not starting with '('");
1300 
1301   BalancedDelimiterTracker T(*this, tok::l_paren);
1302   T.consumeOpen();
1303 
1304   if (Tok.isNot(tok::identifier)) {
1305     Diag(Tok, diag::err_expected) << tok::identifier;
1306     T.skipToEnd();
1307     return;
1308   }
1309   IdentifierLoc *ArgumentKind = ParseIdentifierLoc();
1310 
1311   if (ExpectAndConsume(tok::comma)) {
1312     T.skipToEnd();
1313     return;
1314   }
1315 
1316   SourceRange MatchingCTypeRange;
1317   TypeResult MatchingCType = ParseTypeName(&MatchingCTypeRange);
1318   if (MatchingCType.isInvalid()) {
1319     T.skipToEnd();
1320     return;
1321   }
1322 
1323   bool LayoutCompatible = false;
1324   bool MustBeNull = false;
1325   while (TryConsumeToken(tok::comma)) {
1326     if (Tok.isNot(tok::identifier)) {
1327       Diag(Tok, diag::err_expected) << tok::identifier;
1328       T.skipToEnd();
1329       return;
1330     }
1331     IdentifierInfo *Flag = Tok.getIdentifierInfo();
1332     if (Flag->isStr("layout_compatible"))
1333       LayoutCompatible = true;
1334     else if (Flag->isStr("must_be_null"))
1335       MustBeNull = true;
1336     else {
1337       Diag(Tok, diag::err_type_safety_unknown_flag) << Flag;
1338       T.skipToEnd();
1339       return;
1340     }
1341     ConsumeToken(); // consume flag
1342   }
1343 
1344   if (!T.consumeClose()) {
1345     Attrs.addNewTypeTagForDatatype(&AttrName, AttrNameLoc, ScopeName, ScopeLoc,
1346                                    ArgumentKind, MatchingCType.get(),
1347                                    LayoutCompatible, MustBeNull, Syntax);
1348   }
1349 
1350   if (EndLoc)
1351     *EndLoc = T.getCloseLocation();
1352 }
1353 
1354 /// DiagnoseProhibitedCXX11Attribute - We have found the opening square brackets
1355 /// of a C++11 attribute-specifier in a location where an attribute is not
1356 /// permitted. By C++11 [dcl.attr.grammar]p6, this is ill-formed. Diagnose this
1357 /// situation.
1358 ///
1359 /// \return \c true if we skipped an attribute-like chunk of tokens, \c false if
1360 /// this doesn't appear to actually be an attribute-specifier, and the caller
1361 /// should try to parse it.
1362 bool Parser::DiagnoseProhibitedCXX11Attribute() {
1363   assert(Tok.is(tok::l_square) && NextToken().is(tok::l_square));
1364 
1365   switch (isCXX11AttributeSpecifier(/*Disambiguate*/true)) {
1366   case CAK_NotAttributeSpecifier:
1367     // No diagnostic: we're in Obj-C++11 and this is not actually an attribute.
1368     return false;
1369 
1370   case CAK_InvalidAttributeSpecifier:
1371     Diag(Tok.getLocation(), diag::err_l_square_l_square_not_attribute);
1372     return false;
1373 
1374   case CAK_AttributeSpecifier:
1375     // Parse and discard the attributes.
1376     SourceLocation BeginLoc = ConsumeBracket();
1377     ConsumeBracket();
1378     SkipUntil(tok::r_square);
1379     assert(Tok.is(tok::r_square) && "isCXX11AttributeSpecifier lied");
1380     SourceLocation EndLoc = ConsumeBracket();
1381     Diag(BeginLoc, diag::err_attributes_not_allowed)
1382       << SourceRange(BeginLoc, EndLoc);
1383     return true;
1384   }
1385   llvm_unreachable("All cases handled above.");
1386 }
1387 
1388 /// \brief We have found the opening square brackets of a C++11
1389 /// attribute-specifier in a location where an attribute is not permitted, but
1390 /// we know where the attributes ought to be written. Parse them anyway, and
1391 /// provide a fixit moving them to the right place.
1392 void Parser::DiagnoseMisplacedCXX11Attribute(ParsedAttributesWithRange &Attrs,
1393                                              SourceLocation CorrectLocation) {
1394   assert((Tok.is(tok::l_square) && NextToken().is(tok::l_square)) ||
1395          Tok.is(tok::kw_alignas));
1396 
1397   // Consume the attributes.
1398   SourceLocation Loc = Tok.getLocation();
1399   ParseCXX11Attributes(Attrs);
1400   CharSourceRange AttrRange(SourceRange(Loc, Attrs.Range.getEnd()), true);
1401 
1402   Diag(Loc, diag::err_attributes_not_allowed)
1403     << FixItHint::CreateInsertionFromRange(CorrectLocation, AttrRange)
1404     << FixItHint::CreateRemoval(AttrRange);
1405 }
1406 
1407 void Parser::DiagnoseProhibitedAttributes(ParsedAttributesWithRange &attrs) {
1408   Diag(attrs.Range.getBegin(), diag::err_attributes_not_allowed)
1409     << attrs.Range;
1410 }
1411 
1412 void Parser::ProhibitCXX11Attributes(ParsedAttributesWithRange &Attrs,
1413                                      unsigned DiagID) {
1414   for (AttributeList *Attr = Attrs.getList(); Attr; Attr = Attr->getNext()) {
1415     if (!Attr->isCXX11Attribute())
1416       continue;
1417     if (Attr->getKind() == AttributeList::UnknownAttribute)
1418       Diag(Attr->getLoc(), diag::warn_unknown_attribute_ignored)
1419           << Attr->getName();
1420     else {
1421       Diag(Attr->getLoc(), DiagID)
1422         << Attr->getName();
1423       Attr->setInvalid();
1424     }
1425   }
1426 }
1427 
1428 // Usually, `__attribute__((attrib)) class Foo {} var` means that attribute
1429 // applies to var, not the type Foo.
1430 // As an exception to the rule, __declspec(align(...)) before the
1431 // class-key affects the type instead of the variable.
1432 // Also, Microsoft-style [attributes] seem to affect the type instead of the
1433 // variable.
1434 // This function moves attributes that should apply to the type off DS to Attrs.
1435 void Parser::stripTypeAttributesOffDeclSpec(ParsedAttributesWithRange &Attrs,
1436                                             DeclSpec &DS,
1437                                             Sema::TagUseKind TUK) {
1438   if (TUK == Sema::TUK_Reference)
1439     return;
1440 
1441   ParsedAttributes &PA = DS.getAttributes();
1442   AttributeList *AL = PA.getList();
1443   AttributeList *Prev = nullptr;
1444   AttributeList *TypeAttrHead = nullptr;
1445   AttributeList *TypeAttrTail = nullptr;
1446   while (AL) {
1447     AttributeList *Next = AL->getNext();
1448 
1449     if ((AL->getKind() == AttributeList::AT_Aligned &&
1450          AL->isDeclspecAttribute()) ||
1451         AL->isMicrosoftAttribute()) {
1452       // Stitch the attribute into the tag's attribute list.
1453       if (TypeAttrTail)
1454         TypeAttrTail->setNext(AL);
1455       else
1456         TypeAttrHead = AL;
1457       TypeAttrTail = AL;
1458       TypeAttrTail->setNext(nullptr);
1459 
1460       // Remove the attribute from the variable's attribute list.
1461       if (Prev) {
1462         // Set the last variable attribute's next attribute to be the attribute
1463         // after the current one.
1464         Prev->setNext(Next);
1465       } else {
1466         // Removing the head of the list requires us to reset the head to the
1467         // next attribute.
1468         PA.set(Next);
1469       }
1470     } else {
1471       Prev = AL;
1472     }
1473 
1474     AL = Next;
1475   }
1476 
1477   // Find end of type attributes Attrs and add NewTypeAttributes in the same
1478   // order they were in originally.  (Remember, in AttributeList things earlier
1479   // in source order are later in the list, since new attributes are added to
1480   // the front of the list.)
1481   Attrs.addAllAtEnd(TypeAttrHead);
1482 }
1483 
1484 /// ParseDeclaration - Parse a full 'declaration', which consists of
1485 /// declaration-specifiers, some number of declarators, and a semicolon.
1486 /// 'Context' should be a Declarator::TheContext value.  This returns the
1487 /// location of the semicolon in DeclEnd.
1488 ///
1489 ///       declaration: [C99 6.7]
1490 ///         block-declaration ->
1491 ///           simple-declaration
1492 ///           others                   [FIXME]
1493 /// [C++]   template-declaration
1494 /// [C++]   namespace-definition
1495 /// [C++]   using-directive
1496 /// [C++]   using-declaration
1497 /// [C++11/C11] static_assert-declaration
1498 ///         others... [FIXME]
1499 ///
1500 Parser::DeclGroupPtrTy Parser::ParseDeclaration(unsigned Context,
1501                                                 SourceLocation &DeclEnd,
1502                                           ParsedAttributesWithRange &attrs) {
1503   ParenBraceBracketBalancer BalancerRAIIObj(*this);
1504   // Must temporarily exit the objective-c container scope for
1505   // parsing c none objective-c decls.
1506   ObjCDeclContextSwitch ObjCDC(*this);
1507 
1508   Decl *SingleDecl = nullptr;
1509   Decl *OwnedType = nullptr;
1510   switch (Tok.getKind()) {
1511   case tok::kw_template:
1512   case tok::kw_export:
1513     ProhibitAttributes(attrs);
1514     SingleDecl = ParseDeclarationStartingWithTemplate(Context, DeclEnd);
1515     break;
1516   case tok::kw_inline:
1517     // Could be the start of an inline namespace. Allowed as an ext in C++03.
1518     if (getLangOpts().CPlusPlus && NextToken().is(tok::kw_namespace)) {
1519       ProhibitAttributes(attrs);
1520       SourceLocation InlineLoc = ConsumeToken();
1521       return ParseNamespace(Context, DeclEnd, InlineLoc);
1522     }
1523     return ParseSimpleDeclaration(Context, DeclEnd, attrs,
1524                                   true);
1525   case tok::kw_namespace:
1526     ProhibitAttributes(attrs);
1527     return ParseNamespace(Context, DeclEnd);
1528   case tok::kw_using:
1529     SingleDecl = ParseUsingDirectiveOrDeclaration(Context, ParsedTemplateInfo(),
1530                                                   DeclEnd, attrs, &OwnedType);
1531     break;
1532   case tok::kw_static_assert:
1533   case tok::kw__Static_assert:
1534     ProhibitAttributes(attrs);
1535     SingleDecl = ParseStaticAssertDeclaration(DeclEnd);
1536     break;
1537   default:
1538     return ParseSimpleDeclaration(Context, DeclEnd, attrs, true);
1539   }
1540 
1541   // This routine returns a DeclGroup, if the thing we parsed only contains a
1542   // single decl, convert it now. Alias declarations can also declare a type;
1543   // include that too if it is present.
1544   return Actions.ConvertDeclToDeclGroup(SingleDecl, OwnedType);
1545 }
1546 
1547 ///       simple-declaration: [C99 6.7: declaration] [C++ 7p1: dcl.dcl]
1548 ///         declaration-specifiers init-declarator-list[opt] ';'
1549 /// [C++11] attribute-specifier-seq decl-specifier-seq[opt]
1550 ///             init-declarator-list ';'
1551 ///[C90/C++]init-declarator-list ';'                             [TODO]
1552 /// [OMP]   threadprivate-directive                              [TODO]
1553 ///
1554 ///       for-range-declaration: [C++11 6.5p1: stmt.ranged]
1555 ///         attribute-specifier-seq[opt] type-specifier-seq declarator
1556 ///
1557 /// If RequireSemi is false, this does not check for a ';' at the end of the
1558 /// declaration.  If it is true, it checks for and eats it.
1559 ///
1560 /// If FRI is non-null, we might be parsing a for-range-declaration instead
1561 /// of a simple-declaration. If we find that we are, we also parse the
1562 /// for-range-initializer, and place it here.
1563 Parser::DeclGroupPtrTy
1564 Parser::ParseSimpleDeclaration(unsigned Context,
1565                                SourceLocation &DeclEnd,
1566                                ParsedAttributesWithRange &Attrs,
1567                                bool RequireSemi, ForRangeInit *FRI) {
1568   // Parse the common declaration-specifiers piece.
1569   ParsingDeclSpec DS(*this);
1570 
1571   DeclSpecContext DSContext = getDeclSpecContextFromDeclaratorContext(Context);
1572   ParseDeclarationSpecifiers(DS, ParsedTemplateInfo(), AS_none, DSContext);
1573 
1574   // If we had a free-standing type definition with a missing semicolon, we
1575   // may get this far before the problem becomes obvious.
1576   if (DS.hasTagDefinition() &&
1577       DiagnoseMissingSemiAfterTagDefinition(DS, AS_none, DSContext))
1578     return nullptr;
1579 
1580   // C99 6.7.2.3p6: Handle "struct-or-union identifier;", "enum { X };"
1581   // declaration-specifiers init-declarator-list[opt] ';'
1582   if (Tok.is(tok::semi)) {
1583     ProhibitAttributes(Attrs);
1584     DeclEnd = Tok.getLocation();
1585     if (RequireSemi) ConsumeToken();
1586     RecordDecl *AnonRecord = nullptr;
1587     Decl *TheDecl = Actions.ParsedFreeStandingDeclSpec(getCurScope(), AS_none,
1588                                                        DS, AnonRecord);
1589     DS.complete(TheDecl);
1590     if (AnonRecord) {
1591       Decl* decls[] = {AnonRecord, TheDecl};
1592       return Actions.BuildDeclaratorGroup(decls, /*TypeMayContainAuto=*/false);
1593     }
1594     return Actions.ConvertDeclToDeclGroup(TheDecl);
1595   }
1596 
1597   DS.takeAttributesFrom(Attrs);
1598   return ParseDeclGroup(DS, Context, &DeclEnd, FRI);
1599 }
1600 
1601 /// Returns true if this might be the start of a declarator, or a common typo
1602 /// for a declarator.
1603 bool Parser::MightBeDeclarator(unsigned Context) {
1604   switch (Tok.getKind()) {
1605   case tok::annot_cxxscope:
1606   case tok::annot_template_id:
1607   case tok::caret:
1608   case tok::code_completion:
1609   case tok::coloncolon:
1610   case tok::ellipsis:
1611   case tok::kw___attribute:
1612   case tok::kw_operator:
1613   case tok::l_paren:
1614   case tok::star:
1615     return true;
1616 
1617   case tok::amp:
1618   case tok::ampamp:
1619     return getLangOpts().CPlusPlus;
1620 
1621   case tok::l_square: // Might be an attribute on an unnamed bit-field.
1622     return Context == Declarator::MemberContext && getLangOpts().CPlusPlus11 &&
1623            NextToken().is(tok::l_square);
1624 
1625   case tok::colon: // Might be a typo for '::' or an unnamed bit-field.
1626     return Context == Declarator::MemberContext || getLangOpts().CPlusPlus;
1627 
1628   case tok::identifier:
1629     switch (NextToken().getKind()) {
1630     case tok::code_completion:
1631     case tok::coloncolon:
1632     case tok::comma:
1633     case tok::equal:
1634     case tok::equalequal: // Might be a typo for '='.
1635     case tok::kw_alignas:
1636     case tok::kw_asm:
1637     case tok::kw___attribute:
1638     case tok::l_brace:
1639     case tok::l_paren:
1640     case tok::l_square:
1641     case tok::less:
1642     case tok::r_brace:
1643     case tok::r_paren:
1644     case tok::r_square:
1645     case tok::semi:
1646       return true;
1647 
1648     case tok::colon:
1649       // At namespace scope, 'identifier:' is probably a typo for 'identifier::'
1650       // and in block scope it's probably a label. Inside a class definition,
1651       // this is a bit-field.
1652       return Context == Declarator::MemberContext ||
1653              (getLangOpts().CPlusPlus && Context == Declarator::FileContext);
1654 
1655     case tok::identifier: // Possible virt-specifier.
1656       return getLangOpts().CPlusPlus11 && isCXX11VirtSpecifier(NextToken());
1657 
1658     default:
1659       return false;
1660     }
1661 
1662   default:
1663     return false;
1664   }
1665 }
1666 
1667 /// Skip until we reach something which seems like a sensible place to pick
1668 /// up parsing after a malformed declaration. This will sometimes stop sooner
1669 /// than SkipUntil(tok::r_brace) would, but will never stop later.
1670 void Parser::SkipMalformedDecl() {
1671   while (true) {
1672     switch (Tok.getKind()) {
1673     case tok::l_brace:
1674       // Skip until matching }, then stop. We've probably skipped over
1675       // a malformed class or function definition or similar.
1676       ConsumeBrace();
1677       SkipUntil(tok::r_brace);
1678       if (Tok.isOneOf(tok::comma, tok::l_brace, tok::kw_try)) {
1679         // This declaration isn't over yet. Keep skipping.
1680         continue;
1681       }
1682       TryConsumeToken(tok::semi);
1683       return;
1684 
1685     case tok::l_square:
1686       ConsumeBracket();
1687       SkipUntil(tok::r_square);
1688       continue;
1689 
1690     case tok::l_paren:
1691       ConsumeParen();
1692       SkipUntil(tok::r_paren);
1693       continue;
1694 
1695     case tok::r_brace:
1696       return;
1697 
1698     case tok::semi:
1699       ConsumeToken();
1700       return;
1701 
1702     case tok::kw_inline:
1703       // 'inline namespace' at the start of a line is almost certainly
1704       // a good place to pick back up parsing, except in an Objective-C
1705       // @interface context.
1706       if (Tok.isAtStartOfLine() && NextToken().is(tok::kw_namespace) &&
1707           (!ParsingInObjCContainer || CurParsedObjCImpl))
1708         return;
1709       break;
1710 
1711     case tok::kw_namespace:
1712       // 'namespace' at the start of a line is almost certainly a good
1713       // place to pick back up parsing, except in an Objective-C
1714       // @interface context.
1715       if (Tok.isAtStartOfLine() &&
1716           (!ParsingInObjCContainer || CurParsedObjCImpl))
1717         return;
1718       break;
1719 
1720     case tok::at:
1721       // @end is very much like } in Objective-C contexts.
1722       if (NextToken().isObjCAtKeyword(tok::objc_end) &&
1723           ParsingInObjCContainer)
1724         return;
1725       break;
1726 
1727     case tok::minus:
1728     case tok::plus:
1729       // - and + probably start new method declarations in Objective-C contexts.
1730       if (Tok.isAtStartOfLine() && ParsingInObjCContainer)
1731         return;
1732       break;
1733 
1734     case tok::eof:
1735     case tok::annot_module_begin:
1736     case tok::annot_module_end:
1737     case tok::annot_module_include:
1738       return;
1739 
1740     default:
1741       break;
1742     }
1743 
1744     ConsumeAnyToken();
1745   }
1746 }
1747 
1748 /// ParseDeclGroup - Having concluded that this is either a function
1749 /// definition or a group of object declarations, actually parse the
1750 /// result.
1751 Parser::DeclGroupPtrTy Parser::ParseDeclGroup(ParsingDeclSpec &DS,
1752                                               unsigned Context,
1753                                               SourceLocation *DeclEnd,
1754                                               ForRangeInit *FRI) {
1755   // Parse the first declarator.
1756   ParsingDeclarator D(*this, DS, static_cast<Declarator::TheContext>(Context));
1757   ParseDeclarator(D);
1758 
1759   // Bail out if the first declarator didn't seem well-formed.
1760   if (!D.hasName() && !D.mayOmitIdentifier()) {
1761     SkipMalformedDecl();
1762     return nullptr;
1763   }
1764 
1765   // Save late-parsed attributes for now; they need to be parsed in the
1766   // appropriate function scope after the function Decl has been constructed.
1767   // These will be parsed in ParseFunctionDefinition or ParseLexedAttrList.
1768   LateParsedAttrList LateParsedAttrs(true);
1769   if (D.isFunctionDeclarator()) {
1770     MaybeParseGNUAttributes(D, &LateParsedAttrs);
1771 
1772     // The _Noreturn keyword can't appear here, unlike the GNU noreturn
1773     // attribute. If we find the keyword here, tell the user to put it
1774     // at the start instead.
1775     if (Tok.is(tok::kw__Noreturn)) {
1776       SourceLocation Loc = ConsumeToken();
1777       const char *PrevSpec;
1778       unsigned DiagID;
1779 
1780       // We can offer a fixit if it's valid to mark this function as _Noreturn
1781       // and we don't have any other declarators in this declaration.
1782       bool Fixit = !DS.setFunctionSpecNoreturn(Loc, PrevSpec, DiagID);
1783       MaybeParseGNUAttributes(D, &LateParsedAttrs);
1784       Fixit &= Tok.isOneOf(tok::semi, tok::l_brace, tok::kw_try);
1785 
1786       Diag(Loc, diag::err_c11_noreturn_misplaced)
1787           << (Fixit ? FixItHint::CreateRemoval(Loc) : FixItHint())
1788           << (Fixit ? FixItHint::CreateInsertion(D.getLocStart(), "_Noreturn ")
1789                     : FixItHint());
1790     }
1791   }
1792 
1793   // Check to see if we have a function *definition* which must have a body.
1794   if (D.isFunctionDeclarator() &&
1795       // Look at the next token to make sure that this isn't a function
1796       // declaration.  We have to check this because __attribute__ might be the
1797       // start of a function definition in GCC-extended K&R C.
1798       !isDeclarationAfterDeclarator()) {
1799 
1800     // Function definitions are only allowed at file scope and in C++ classes.
1801     // The C++ inline method definition case is handled elsewhere, so we only
1802     // need to handle the file scope definition case.
1803     if (Context == Declarator::FileContext) {
1804       if (isStartOfFunctionDefinition(D)) {
1805         if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef) {
1806           Diag(Tok, diag::err_function_declared_typedef);
1807 
1808           // Recover by treating the 'typedef' as spurious.
1809           DS.ClearStorageClassSpecs();
1810         }
1811 
1812         Decl *TheDecl =
1813           ParseFunctionDefinition(D, ParsedTemplateInfo(), &LateParsedAttrs);
1814         return Actions.ConvertDeclToDeclGroup(TheDecl);
1815       }
1816 
1817       if (isDeclarationSpecifier()) {
1818         // If there is an invalid declaration specifier right after the
1819         // function prototype, then we must be in a missing semicolon case
1820         // where this isn't actually a body.  Just fall through into the code
1821         // that handles it as a prototype, and let the top-level code handle
1822         // the erroneous declspec where it would otherwise expect a comma or
1823         // semicolon.
1824       } else {
1825         Diag(Tok, diag::err_expected_fn_body);
1826         SkipUntil(tok::semi);
1827         return nullptr;
1828       }
1829     } else {
1830       if (Tok.is(tok::l_brace)) {
1831         Diag(Tok, diag::err_function_definition_not_allowed);
1832         SkipMalformedDecl();
1833         return nullptr;
1834       }
1835     }
1836   }
1837 
1838   if (ParseAsmAttributesAfterDeclarator(D))
1839     return nullptr;
1840 
1841   // C++0x [stmt.iter]p1: Check if we have a for-range-declarator. If so, we
1842   // must parse and analyze the for-range-initializer before the declaration is
1843   // analyzed.
1844   //
1845   // Handle the Objective-C for-in loop variable similarly, although we
1846   // don't need to parse the container in advance.
1847   if (FRI && (Tok.is(tok::colon) || isTokIdentifier_in())) {
1848     bool IsForRangeLoop = false;
1849     if (TryConsumeToken(tok::colon, FRI->ColonLoc)) {
1850       IsForRangeLoop = true;
1851       if (Tok.is(tok::l_brace))
1852         FRI->RangeExpr = ParseBraceInitializer();
1853       else
1854         FRI->RangeExpr = ParseExpression();
1855     }
1856 
1857     Decl *ThisDecl = Actions.ActOnDeclarator(getCurScope(), D);
1858     if (IsForRangeLoop)
1859       Actions.ActOnCXXForRangeDecl(ThisDecl);
1860     Actions.FinalizeDeclaration(ThisDecl);
1861     D.complete(ThisDecl);
1862     return Actions.FinalizeDeclaratorGroup(getCurScope(), DS, ThisDecl);
1863   }
1864 
1865   SmallVector<Decl *, 8> DeclsInGroup;
1866   Decl *FirstDecl = ParseDeclarationAfterDeclaratorAndAttributes(
1867       D, ParsedTemplateInfo(), FRI);
1868   if (LateParsedAttrs.size() > 0)
1869     ParseLexedAttributeList(LateParsedAttrs, FirstDecl, true, false);
1870   D.complete(FirstDecl);
1871   if (FirstDecl)
1872     DeclsInGroup.push_back(FirstDecl);
1873 
1874   bool ExpectSemi = Context != Declarator::ForContext;
1875 
1876   // If we don't have a comma, it is either the end of the list (a ';') or an
1877   // error, bail out.
1878   SourceLocation CommaLoc;
1879   while (TryConsumeToken(tok::comma, CommaLoc)) {
1880     if (Tok.isAtStartOfLine() && ExpectSemi && !MightBeDeclarator(Context)) {
1881       // This comma was followed by a line-break and something which can't be
1882       // the start of a declarator. The comma was probably a typo for a
1883       // semicolon.
1884       Diag(CommaLoc, diag::err_expected_semi_declaration)
1885         << FixItHint::CreateReplacement(CommaLoc, ";");
1886       ExpectSemi = false;
1887       break;
1888     }
1889 
1890     // Parse the next declarator.
1891     D.clear();
1892     D.setCommaLoc(CommaLoc);
1893 
1894     // Accept attributes in an init-declarator.  In the first declarator in a
1895     // declaration, these would be part of the declspec.  In subsequent
1896     // declarators, they become part of the declarator itself, so that they
1897     // don't apply to declarators after *this* one.  Examples:
1898     //    short __attribute__((common)) var;    -> declspec
1899     //    short var __attribute__((common));    -> declarator
1900     //    short x, __attribute__((common)) var;    -> declarator
1901     MaybeParseGNUAttributes(D);
1902 
1903     // MSVC parses but ignores qualifiers after the comma as an extension.
1904     if (getLangOpts().MicrosoftExt)
1905       DiagnoseAndSkipExtendedMicrosoftTypeAttributes();
1906 
1907     ParseDeclarator(D);
1908     if (!D.isInvalidType()) {
1909       Decl *ThisDecl = ParseDeclarationAfterDeclarator(D);
1910       D.complete(ThisDecl);
1911       if (ThisDecl)
1912         DeclsInGroup.push_back(ThisDecl);
1913     }
1914   }
1915 
1916   if (DeclEnd)
1917     *DeclEnd = Tok.getLocation();
1918 
1919   if (ExpectSemi &&
1920       ExpectAndConsumeSemi(Context == Declarator::FileContext
1921                            ? diag::err_invalid_token_after_toplevel_declarator
1922                            : diag::err_expected_semi_declaration)) {
1923     // Okay, there was no semicolon and one was expected.  If we see a
1924     // declaration specifier, just assume it was missing and continue parsing.
1925     // Otherwise things are very confused and we skip to recover.
1926     if (!isDeclarationSpecifier()) {
1927       SkipUntil(tok::r_brace, StopAtSemi | StopBeforeMatch);
1928       TryConsumeToken(tok::semi);
1929     }
1930   }
1931 
1932   return Actions.FinalizeDeclaratorGroup(getCurScope(), DS, DeclsInGroup);
1933 }
1934 
1935 /// Parse an optional simple-asm-expr and attributes, and attach them to a
1936 /// declarator. Returns true on an error.
1937 bool Parser::ParseAsmAttributesAfterDeclarator(Declarator &D) {
1938   // If a simple-asm-expr is present, parse it.
1939   if (Tok.is(tok::kw_asm)) {
1940     SourceLocation Loc;
1941     ExprResult AsmLabel(ParseSimpleAsm(&Loc));
1942     if (AsmLabel.isInvalid()) {
1943       SkipUntil(tok::semi, StopBeforeMatch);
1944       return true;
1945     }
1946 
1947     D.setAsmLabel(AsmLabel.get());
1948     D.SetRangeEnd(Loc);
1949   }
1950 
1951   MaybeParseGNUAttributes(D);
1952   return false;
1953 }
1954 
1955 /// \brief Parse 'declaration' after parsing 'declaration-specifiers
1956 /// declarator'. This method parses the remainder of the declaration
1957 /// (including any attributes or initializer, among other things) and
1958 /// finalizes the declaration.
1959 ///
1960 ///       init-declarator: [C99 6.7]
1961 ///         declarator
1962 ///         declarator '=' initializer
1963 /// [GNU]   declarator simple-asm-expr[opt] attributes[opt]
1964 /// [GNU]   declarator simple-asm-expr[opt] attributes[opt] '=' initializer
1965 /// [C++]   declarator initializer[opt]
1966 ///
1967 /// [C++] initializer:
1968 /// [C++]   '=' initializer-clause
1969 /// [C++]   '(' expression-list ')'
1970 /// [C++0x] '=' 'default'                                                [TODO]
1971 /// [C++0x] '=' 'delete'
1972 /// [C++0x] braced-init-list
1973 ///
1974 /// According to the standard grammar, =default and =delete are function
1975 /// definitions, but that definitely doesn't fit with the parser here.
1976 ///
1977 Decl *Parser::ParseDeclarationAfterDeclarator(
1978     Declarator &D, const ParsedTemplateInfo &TemplateInfo) {
1979   if (ParseAsmAttributesAfterDeclarator(D))
1980     return nullptr;
1981 
1982   return ParseDeclarationAfterDeclaratorAndAttributes(D, TemplateInfo);
1983 }
1984 
1985 Decl *Parser::ParseDeclarationAfterDeclaratorAndAttributes(
1986     Declarator &D, const ParsedTemplateInfo &TemplateInfo, ForRangeInit *FRI) {
1987   // Inform the current actions module that we just parsed this declarator.
1988   Decl *ThisDecl = nullptr;
1989   switch (TemplateInfo.Kind) {
1990   case ParsedTemplateInfo::NonTemplate:
1991     ThisDecl = Actions.ActOnDeclarator(getCurScope(), D);
1992     break;
1993 
1994   case ParsedTemplateInfo::Template:
1995   case ParsedTemplateInfo::ExplicitSpecialization: {
1996     ThisDecl = Actions.ActOnTemplateDeclarator(getCurScope(),
1997                                                *TemplateInfo.TemplateParams,
1998                                                D);
1999     if (VarTemplateDecl *VT = dyn_cast_or_null<VarTemplateDecl>(ThisDecl))
2000       // Re-direct this decl to refer to the templated decl so that we can
2001       // initialize it.
2002       ThisDecl = VT->getTemplatedDecl();
2003     break;
2004   }
2005   case ParsedTemplateInfo::ExplicitInstantiation: {
2006     if (Tok.is(tok::semi)) {
2007       DeclResult ThisRes = Actions.ActOnExplicitInstantiation(
2008           getCurScope(), TemplateInfo.ExternLoc, TemplateInfo.TemplateLoc, D);
2009       if (ThisRes.isInvalid()) {
2010         SkipUntil(tok::semi, StopBeforeMatch);
2011         return nullptr;
2012       }
2013       ThisDecl = ThisRes.get();
2014     } else {
2015       // FIXME: This check should be for a variable template instantiation only.
2016 
2017       // Check that this is a valid instantiation
2018       if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
2019         // If the declarator-id is not a template-id, issue a diagnostic and
2020         // recover by ignoring the 'template' keyword.
2021         Diag(Tok, diag::err_template_defn_explicit_instantiation)
2022             << 2 << FixItHint::CreateRemoval(TemplateInfo.TemplateLoc);
2023         ThisDecl = Actions.ActOnDeclarator(getCurScope(), D);
2024       } else {
2025         SourceLocation LAngleLoc =
2026             PP.getLocForEndOfToken(TemplateInfo.TemplateLoc);
2027         Diag(D.getIdentifierLoc(),
2028              diag::err_explicit_instantiation_with_definition)
2029             << SourceRange(TemplateInfo.TemplateLoc)
2030             << FixItHint::CreateInsertion(LAngleLoc, "<>");
2031 
2032         // Recover as if it were an explicit specialization.
2033         TemplateParameterLists FakedParamLists;
2034         FakedParamLists.push_back(Actions.ActOnTemplateParameterList(
2035             0, SourceLocation(), TemplateInfo.TemplateLoc, LAngleLoc, None,
2036             LAngleLoc, nullptr));
2037 
2038         ThisDecl =
2039             Actions.ActOnTemplateDeclarator(getCurScope(), FakedParamLists, D);
2040       }
2041     }
2042     break;
2043     }
2044   }
2045 
2046   bool TypeContainsAuto = D.getDeclSpec().containsPlaceholderType();
2047 
2048   // Parse declarator '=' initializer.
2049   // If a '==' or '+=' is found, suggest a fixit to '='.
2050   if (isTokenEqualOrEqualTypo()) {
2051     SourceLocation EqualLoc = ConsumeToken();
2052 
2053     if (Tok.is(tok::kw_delete)) {
2054       if (D.isFunctionDeclarator())
2055         Diag(ConsumeToken(), diag::err_default_delete_in_multiple_declaration)
2056           << 1 /* delete */;
2057       else
2058         Diag(ConsumeToken(), diag::err_deleted_non_function);
2059     } else if (Tok.is(tok::kw_default)) {
2060       if (D.isFunctionDeclarator())
2061         Diag(ConsumeToken(), diag::err_default_delete_in_multiple_declaration)
2062           << 0 /* default */;
2063       else
2064         Diag(ConsumeToken(), diag::err_default_special_members);
2065     } else {
2066       if (getLangOpts().CPlusPlus && D.getCXXScopeSpec().isSet()) {
2067         EnterScope(0);
2068         Actions.ActOnCXXEnterDeclInitializer(getCurScope(), ThisDecl);
2069       }
2070 
2071       if (Tok.is(tok::code_completion)) {
2072         Actions.CodeCompleteInitializer(getCurScope(), ThisDecl);
2073         Actions.FinalizeDeclaration(ThisDecl);
2074         cutOffParsing();
2075         return nullptr;
2076       }
2077 
2078       ExprResult Init(ParseInitializer());
2079 
2080       // If this is the only decl in (possibly) range based for statement,
2081       // our best guess is that the user meant ':' instead of '='.
2082       if (Tok.is(tok::r_paren) && FRI && D.isFirstDeclarator()) {
2083         Diag(EqualLoc, diag::err_single_decl_assign_in_for_range)
2084             << FixItHint::CreateReplacement(EqualLoc, ":");
2085         // We are trying to stop parser from looking for ';' in this for
2086         // statement, therefore preventing spurious errors to be issued.
2087         FRI->ColonLoc = EqualLoc;
2088         Init = ExprError();
2089         FRI->RangeExpr = Init;
2090       }
2091 
2092       if (getLangOpts().CPlusPlus && D.getCXXScopeSpec().isSet()) {
2093         Actions.ActOnCXXExitDeclInitializer(getCurScope(), ThisDecl);
2094         ExitScope();
2095       }
2096 
2097       if (Init.isInvalid()) {
2098         SmallVector<tok::TokenKind, 2> StopTokens;
2099         StopTokens.push_back(tok::comma);
2100         if (D.getContext() == Declarator::ForContext ||
2101             D.getContext() == Declarator::InitStmtContext)
2102           StopTokens.push_back(tok::r_paren);
2103         SkipUntil(StopTokens, StopAtSemi | StopBeforeMatch);
2104         Actions.ActOnInitializerError(ThisDecl);
2105       } else
2106         Actions.AddInitializerToDecl(ThisDecl, Init.get(),
2107                                      /*DirectInit=*/false, TypeContainsAuto);
2108     }
2109   } else if (Tok.is(tok::l_paren)) {
2110     // Parse C++ direct initializer: '(' expression-list ')'
2111     BalancedDelimiterTracker T(*this, tok::l_paren);
2112     T.consumeOpen();
2113 
2114     ExprVector Exprs;
2115     CommaLocsTy CommaLocs;
2116 
2117     if (getLangOpts().CPlusPlus && D.getCXXScopeSpec().isSet()) {
2118       EnterScope(0);
2119       Actions.ActOnCXXEnterDeclInitializer(getCurScope(), ThisDecl);
2120     }
2121 
2122     if (ParseExpressionList(Exprs, CommaLocs, [&] {
2123           Actions.CodeCompleteConstructor(getCurScope(),
2124                  cast<VarDecl>(ThisDecl)->getType()->getCanonicalTypeInternal(),
2125                                           ThisDecl->getLocation(), Exprs);
2126        })) {
2127       Actions.ActOnInitializerError(ThisDecl);
2128       SkipUntil(tok::r_paren, StopAtSemi);
2129 
2130       if (getLangOpts().CPlusPlus && D.getCXXScopeSpec().isSet()) {
2131         Actions.ActOnCXXExitDeclInitializer(getCurScope(), ThisDecl);
2132         ExitScope();
2133       }
2134     } else {
2135       // Match the ')'.
2136       T.consumeClose();
2137 
2138       assert(!Exprs.empty() && Exprs.size()-1 == CommaLocs.size() &&
2139              "Unexpected number of commas!");
2140 
2141       if (getLangOpts().CPlusPlus && D.getCXXScopeSpec().isSet()) {
2142         Actions.ActOnCXXExitDeclInitializer(getCurScope(), ThisDecl);
2143         ExitScope();
2144       }
2145 
2146       ExprResult Initializer = Actions.ActOnParenListExpr(T.getOpenLocation(),
2147                                                           T.getCloseLocation(),
2148                                                           Exprs);
2149       Actions.AddInitializerToDecl(ThisDecl, Initializer.get(),
2150                                    /*DirectInit=*/true, TypeContainsAuto);
2151     }
2152   } else if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace) &&
2153              (!CurParsedObjCImpl || !D.isFunctionDeclarator())) {
2154     // Parse C++0x braced-init-list.
2155     Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists);
2156 
2157     if (D.getCXXScopeSpec().isSet()) {
2158       EnterScope(0);
2159       Actions.ActOnCXXEnterDeclInitializer(getCurScope(), ThisDecl);
2160     }
2161 
2162     ExprResult Init(ParseBraceInitializer());
2163 
2164     if (D.getCXXScopeSpec().isSet()) {
2165       Actions.ActOnCXXExitDeclInitializer(getCurScope(), ThisDecl);
2166       ExitScope();
2167     }
2168 
2169     if (Init.isInvalid()) {
2170       Actions.ActOnInitializerError(ThisDecl);
2171     } else
2172       Actions.AddInitializerToDecl(ThisDecl, Init.get(),
2173                                    /*DirectInit=*/true, TypeContainsAuto);
2174 
2175   } else {
2176     Actions.ActOnUninitializedDecl(ThisDecl, TypeContainsAuto);
2177   }
2178 
2179   Actions.FinalizeDeclaration(ThisDecl);
2180 
2181   return ThisDecl;
2182 }
2183 
2184 /// ParseSpecifierQualifierList
2185 ///        specifier-qualifier-list:
2186 ///          type-specifier specifier-qualifier-list[opt]
2187 ///          type-qualifier specifier-qualifier-list[opt]
2188 /// [GNU]    attributes     specifier-qualifier-list[opt]
2189 ///
2190 void Parser::ParseSpecifierQualifierList(DeclSpec &DS, AccessSpecifier AS,
2191                                          DeclSpecContext DSC) {
2192   /// specifier-qualifier-list is a subset of declaration-specifiers.  Just
2193   /// parse declaration-specifiers and complain about extra stuff.
2194   /// TODO: diagnose attribute-specifiers and alignment-specifiers.
2195   ParseDeclarationSpecifiers(DS, ParsedTemplateInfo(), AS, DSC);
2196 
2197   // Validate declspec for type-name.
2198   unsigned Specs = DS.getParsedSpecifiers();
2199   if (isTypeSpecifier(DSC) && !DS.hasTypeSpecifier()) {
2200     Diag(Tok, diag::err_expected_type);
2201     DS.SetTypeSpecError();
2202   } else if (Specs == DeclSpec::PQ_None && !DS.hasAttributes()) {
2203     Diag(Tok, diag::err_typename_requires_specqual);
2204     if (!DS.hasTypeSpecifier())
2205       DS.SetTypeSpecError();
2206   }
2207 
2208   // Issue diagnostic and remove storage class if present.
2209   if (Specs & DeclSpec::PQ_StorageClassSpecifier) {
2210     if (DS.getStorageClassSpecLoc().isValid())
2211       Diag(DS.getStorageClassSpecLoc(),diag::err_typename_invalid_storageclass);
2212     else
2213       Diag(DS.getThreadStorageClassSpecLoc(),
2214            diag::err_typename_invalid_storageclass);
2215     DS.ClearStorageClassSpecs();
2216   }
2217 
2218   // Issue diagnostic and remove function specifier if present.
2219   if (Specs & DeclSpec::PQ_FunctionSpecifier) {
2220     if (DS.isInlineSpecified())
2221       Diag(DS.getInlineSpecLoc(), diag::err_typename_invalid_functionspec);
2222     if (DS.isVirtualSpecified())
2223       Diag(DS.getVirtualSpecLoc(), diag::err_typename_invalid_functionspec);
2224     if (DS.isExplicitSpecified())
2225       Diag(DS.getExplicitSpecLoc(), diag::err_typename_invalid_functionspec);
2226     DS.ClearFunctionSpecs();
2227   }
2228 
2229   // Issue diagnostic and remove constexpr specfier if present.
2230   if (DS.isConstexprSpecified() && DSC != DSC_condition) {
2231     Diag(DS.getConstexprSpecLoc(), diag::err_typename_invalid_constexpr);
2232     DS.ClearConstexprSpec();
2233   }
2234 }
2235 
2236 /// isValidAfterIdentifierInDeclaratorAfterDeclSpec - Return true if the
2237 /// specified token is valid after the identifier in a declarator which
2238 /// immediately follows the declspec.  For example, these things are valid:
2239 ///
2240 ///      int x   [             4];         // direct-declarator
2241 ///      int x   (             int y);     // direct-declarator
2242 ///  int(int x   )                         // direct-declarator
2243 ///      int x   ;                         // simple-declaration
2244 ///      int x   =             17;         // init-declarator-list
2245 ///      int x   ,             y;          // init-declarator-list
2246 ///      int x   __asm__       ("foo");    // init-declarator-list
2247 ///      int x   :             4;          // struct-declarator
2248 ///      int x   {             5};         // C++'0x unified initializers
2249 ///
2250 /// This is not, because 'x' does not immediately follow the declspec (though
2251 /// ')' happens to be valid anyway).
2252 ///    int (x)
2253 ///
2254 static bool isValidAfterIdentifierInDeclarator(const Token &T) {
2255   return T.isOneOf(tok::l_square, tok::l_paren, tok::r_paren, tok::semi,
2256                    tok::comma, tok::equal, tok::kw_asm, tok::l_brace,
2257                    tok::colon);
2258 }
2259 
2260 /// ParseImplicitInt - This method is called when we have an non-typename
2261 /// identifier in a declspec (which normally terminates the decl spec) when
2262 /// the declspec has no type specifier.  In this case, the declspec is either
2263 /// malformed or is "implicit int" (in K&R and C89).
2264 ///
2265 /// This method handles diagnosing this prettily and returns false if the
2266 /// declspec is done being processed.  If it recovers and thinks there may be
2267 /// other pieces of declspec after it, it returns true.
2268 ///
2269 bool Parser::ParseImplicitInt(DeclSpec &DS, CXXScopeSpec *SS,
2270                               const ParsedTemplateInfo &TemplateInfo,
2271                               AccessSpecifier AS, DeclSpecContext DSC,
2272                               ParsedAttributesWithRange &Attrs) {
2273   assert(Tok.is(tok::identifier) && "should have identifier");
2274 
2275   SourceLocation Loc = Tok.getLocation();
2276   // If we see an identifier that is not a type name, we normally would
2277   // parse it as the identifer being declared.  However, when a typename
2278   // is typo'd or the definition is not included, this will incorrectly
2279   // parse the typename as the identifier name and fall over misparsing
2280   // later parts of the diagnostic.
2281   //
2282   // As such, we try to do some look-ahead in cases where this would
2283   // otherwise be an "implicit-int" case to see if this is invalid.  For
2284   // example: "static foo_t x = 4;"  In this case, if we parsed foo_t as
2285   // an identifier with implicit int, we'd get a parse error because the
2286   // next token is obviously invalid for a type.  Parse these as a case
2287   // with an invalid type specifier.
2288   assert(!DS.hasTypeSpecifier() && "Type specifier checked above");
2289 
2290   // Since we know that this either implicit int (which is rare) or an
2291   // error, do lookahead to try to do better recovery. This never applies
2292   // within a type specifier. Outside of C++, we allow this even if the
2293   // language doesn't "officially" support implicit int -- we support
2294   // implicit int as an extension in C99 and C11.
2295   if (!isTypeSpecifier(DSC) && !getLangOpts().CPlusPlus &&
2296       isValidAfterIdentifierInDeclarator(NextToken())) {
2297     // If this token is valid for implicit int, e.g. "static x = 4", then
2298     // we just avoid eating the identifier, so it will be parsed as the
2299     // identifier in the declarator.
2300     return false;
2301   }
2302 
2303   if (getLangOpts().CPlusPlus &&
2304       DS.getStorageClassSpec() == DeclSpec::SCS_auto) {
2305     // Don't require a type specifier if we have the 'auto' storage class
2306     // specifier in C++98 -- we'll promote it to a type specifier.
2307     if (SS)
2308       AnnotateScopeToken(*SS, /*IsNewAnnotation*/false);
2309     return false;
2310   }
2311 
2312   if (getLangOpts().CPlusPlus && (!SS || SS->isEmpty()) &&
2313       getLangOpts().MSVCCompat) {
2314     // Lookup of an unqualified type name has failed in MSVC compatibility mode.
2315     // Give Sema a chance to recover if we are in a template with dependent base
2316     // classes.
2317     if (ParsedType T = Actions.ActOnMSVCUnknownTypeName(
2318             *Tok.getIdentifierInfo(), Tok.getLocation(),
2319             DSC == DSC_template_type_arg)) {
2320       const char *PrevSpec;
2321       unsigned DiagID;
2322       DS.SetTypeSpecType(DeclSpec::TST_typename, Loc, PrevSpec, DiagID, T,
2323                          Actions.getASTContext().getPrintingPolicy());
2324       DS.SetRangeEnd(Tok.getLocation());
2325       ConsumeToken();
2326       return false;
2327     }
2328   }
2329 
2330   // Otherwise, if we don't consume this token, we are going to emit an
2331   // error anyway.  Try to recover from various common problems.  Check
2332   // to see if this was a reference to a tag name without a tag specified.
2333   // This is a common problem in C (saying 'foo' instead of 'struct foo').
2334   //
2335   // C++ doesn't need this, and isTagName doesn't take SS.
2336   if (SS == nullptr) {
2337     const char *TagName = nullptr, *FixitTagName = nullptr;
2338     tok::TokenKind TagKind = tok::unknown;
2339 
2340     switch (Actions.isTagName(*Tok.getIdentifierInfo(), getCurScope())) {
2341       default: break;
2342       case DeclSpec::TST_enum:
2343         TagName="enum"  ; FixitTagName = "enum "  ; TagKind=tok::kw_enum ;break;
2344       case DeclSpec::TST_union:
2345         TagName="union" ; FixitTagName = "union " ;TagKind=tok::kw_union ;break;
2346       case DeclSpec::TST_struct:
2347         TagName="struct"; FixitTagName = "struct ";TagKind=tok::kw_struct;break;
2348       case DeclSpec::TST_interface:
2349         TagName="__interface"; FixitTagName = "__interface ";
2350         TagKind=tok::kw___interface;break;
2351       case DeclSpec::TST_class:
2352         TagName="class" ; FixitTagName = "class " ;TagKind=tok::kw_class ;break;
2353     }
2354 
2355     if (TagName) {
2356       IdentifierInfo *TokenName = Tok.getIdentifierInfo();
2357       LookupResult R(Actions, TokenName, SourceLocation(),
2358                      Sema::LookupOrdinaryName);
2359 
2360       Diag(Loc, diag::err_use_of_tag_name_without_tag)
2361         << TokenName << TagName << getLangOpts().CPlusPlus
2362         << FixItHint::CreateInsertion(Tok.getLocation(), FixitTagName);
2363 
2364       if (Actions.LookupParsedName(R, getCurScope(), SS)) {
2365         for (LookupResult::iterator I = R.begin(), IEnd = R.end();
2366              I != IEnd; ++I)
2367           Diag((*I)->getLocation(), diag::note_decl_hiding_tag_type)
2368             << TokenName << TagName;
2369       }
2370 
2371       // Parse this as a tag as if the missing tag were present.
2372       if (TagKind == tok::kw_enum)
2373         ParseEnumSpecifier(Loc, DS, TemplateInfo, AS, DSC_normal);
2374       else
2375         ParseClassSpecifier(TagKind, Loc, DS, TemplateInfo, AS,
2376                             /*EnteringContext*/ false, DSC_normal, Attrs);
2377       return true;
2378     }
2379   }
2380 
2381   // Determine whether this identifier could plausibly be the name of something
2382   // being declared (with a missing type).
2383   if (!isTypeSpecifier(DSC) &&
2384       (!SS || DSC == DSC_top_level || DSC == DSC_class)) {
2385     // Look ahead to the next token to try to figure out what this declaration
2386     // was supposed to be.
2387     switch (NextToken().getKind()) {
2388     case tok::l_paren: {
2389       // static x(4); // 'x' is not a type
2390       // x(int n);    // 'x' is not a type
2391       // x (*p)[];    // 'x' is a type
2392       //
2393       // Since we're in an error case, we can afford to perform a tentative
2394       // parse to determine which case we're in.
2395       TentativeParsingAction PA(*this);
2396       ConsumeToken();
2397       TPResult TPR = TryParseDeclarator(/*mayBeAbstract*/false);
2398       PA.Revert();
2399 
2400       if (TPR != TPResult::False) {
2401         // The identifier is followed by a parenthesized declarator.
2402         // It's supposed to be a type.
2403         break;
2404       }
2405 
2406       // If we're in a context where we could be declaring a constructor,
2407       // check whether this is a constructor declaration with a bogus name.
2408       if (DSC == DSC_class || (DSC == DSC_top_level && SS)) {
2409         IdentifierInfo *II = Tok.getIdentifierInfo();
2410         if (Actions.isCurrentClassNameTypo(II, SS)) {
2411           Diag(Loc, diag::err_constructor_bad_name)
2412             << Tok.getIdentifierInfo() << II
2413             << FixItHint::CreateReplacement(Tok.getLocation(), II->getName());
2414           Tok.setIdentifierInfo(II);
2415         }
2416       }
2417       // Fall through.
2418     }
2419     case tok::comma:
2420     case tok::equal:
2421     case tok::kw_asm:
2422     case tok::l_brace:
2423     case tok::l_square:
2424     case tok::semi:
2425       // This looks like a variable or function declaration. The type is
2426       // probably missing. We're done parsing decl-specifiers.
2427       if (SS)
2428         AnnotateScopeToken(*SS, /*IsNewAnnotation*/false);
2429       return false;
2430 
2431     default:
2432       // This is probably supposed to be a type. This includes cases like:
2433       //   int f(itn);
2434       //   struct S { unsinged : 4; };
2435       break;
2436     }
2437   }
2438 
2439   // This is almost certainly an invalid type name. Let Sema emit a diagnostic
2440   // and attempt to recover.
2441   ParsedType T;
2442   IdentifierInfo *II = Tok.getIdentifierInfo();
2443   Actions.DiagnoseUnknownTypeName(II, Loc, getCurScope(), SS, T,
2444                                   getLangOpts().CPlusPlus &&
2445                                       NextToken().is(tok::less));
2446   if (T) {
2447     // The action has suggested that the type T could be used. Set that as
2448     // the type in the declaration specifiers, consume the would-be type
2449     // name token, and we're done.
2450     const char *PrevSpec;
2451     unsigned DiagID;
2452     DS.SetTypeSpecType(DeclSpec::TST_typename, Loc, PrevSpec, DiagID, T,
2453                        Actions.getASTContext().getPrintingPolicy());
2454     DS.SetRangeEnd(Tok.getLocation());
2455     ConsumeToken();
2456     // There may be other declaration specifiers after this.
2457     return true;
2458   } else if (II != Tok.getIdentifierInfo()) {
2459     // If no type was suggested, the correction is to a keyword
2460     Tok.setKind(II->getTokenID());
2461     // There may be other declaration specifiers after this.
2462     return true;
2463   }
2464 
2465   // Otherwise, the action had no suggestion for us.  Mark this as an error.
2466   DS.SetTypeSpecError();
2467   DS.SetRangeEnd(Tok.getLocation());
2468   ConsumeToken();
2469 
2470   // TODO: Could inject an invalid typedef decl in an enclosing scope to
2471   // avoid rippling error messages on subsequent uses of the same type,
2472   // could be useful if #include was forgotten.
2473   return false;
2474 }
2475 
2476 /// \brief Determine the declaration specifier context from the declarator
2477 /// context.
2478 ///
2479 /// \param Context the declarator context, which is one of the
2480 /// Declarator::TheContext enumerator values.
2481 Parser::DeclSpecContext
2482 Parser::getDeclSpecContextFromDeclaratorContext(unsigned Context) {
2483   if (Context == Declarator::MemberContext)
2484     return DSC_class;
2485   if (Context == Declarator::FileContext)
2486     return DSC_top_level;
2487   if (Context == Declarator::TemplateTypeArgContext)
2488     return DSC_template_type_arg;
2489   if (Context == Declarator::TrailingReturnContext)
2490     return DSC_trailing;
2491   if (Context == Declarator::AliasDeclContext ||
2492       Context == Declarator::AliasTemplateContext)
2493     return DSC_alias_declaration;
2494   return DSC_normal;
2495 }
2496 
2497 /// ParseAlignArgument - Parse the argument to an alignment-specifier.
2498 ///
2499 /// FIXME: Simply returns an alignof() expression if the argument is a
2500 /// type. Ideally, the type should be propagated directly into Sema.
2501 ///
2502 /// [C11]   type-id
2503 /// [C11]   constant-expression
2504 /// [C++0x] type-id ...[opt]
2505 /// [C++0x] assignment-expression ...[opt]
2506 ExprResult Parser::ParseAlignArgument(SourceLocation Start,
2507                                       SourceLocation &EllipsisLoc) {
2508   ExprResult ER;
2509   if (isTypeIdInParens()) {
2510     SourceLocation TypeLoc = Tok.getLocation();
2511     ParsedType Ty = ParseTypeName().get();
2512     SourceRange TypeRange(Start, Tok.getLocation());
2513     ER = Actions.ActOnUnaryExprOrTypeTraitExpr(TypeLoc, UETT_AlignOf, true,
2514                                                Ty.getAsOpaquePtr(), TypeRange);
2515   } else
2516     ER = ParseConstantExpression();
2517 
2518   if (getLangOpts().CPlusPlus11)
2519     TryConsumeToken(tok::ellipsis, EllipsisLoc);
2520 
2521   return ER;
2522 }
2523 
2524 /// ParseAlignmentSpecifier - Parse an alignment-specifier, and add the
2525 /// attribute to Attrs.
2526 ///
2527 /// alignment-specifier:
2528 /// [C11]   '_Alignas' '(' type-id ')'
2529 /// [C11]   '_Alignas' '(' constant-expression ')'
2530 /// [C++11] 'alignas' '(' type-id ...[opt] ')'
2531 /// [C++11] 'alignas' '(' assignment-expression ...[opt] ')'
2532 void Parser::ParseAlignmentSpecifier(ParsedAttributes &Attrs,
2533                                      SourceLocation *EndLoc) {
2534   assert(Tok.isOneOf(tok::kw_alignas, tok::kw__Alignas) &&
2535          "Not an alignment-specifier!");
2536 
2537   IdentifierInfo *KWName = Tok.getIdentifierInfo();
2538   SourceLocation KWLoc = ConsumeToken();
2539 
2540   BalancedDelimiterTracker T(*this, tok::l_paren);
2541   if (T.expectAndConsume())
2542     return;
2543 
2544   SourceLocation EllipsisLoc;
2545   ExprResult ArgExpr = ParseAlignArgument(T.getOpenLocation(), EllipsisLoc);
2546   if (ArgExpr.isInvalid()) {
2547     T.skipToEnd();
2548     return;
2549   }
2550 
2551   T.consumeClose();
2552   if (EndLoc)
2553     *EndLoc = T.getCloseLocation();
2554 
2555   ArgsVector ArgExprs;
2556   ArgExprs.push_back(ArgExpr.get());
2557   Attrs.addNew(KWName, KWLoc, nullptr, KWLoc, ArgExprs.data(), 1,
2558                AttributeList::AS_Keyword, EllipsisLoc);
2559 }
2560 
2561 /// Determine whether we're looking at something that might be a declarator
2562 /// in a simple-declaration. If it can't possibly be a declarator, maybe
2563 /// diagnose a missing semicolon after a prior tag definition in the decl
2564 /// specifier.
2565 ///
2566 /// \return \c true if an error occurred and this can't be any kind of
2567 /// declaration.
2568 bool
2569 Parser::DiagnoseMissingSemiAfterTagDefinition(DeclSpec &DS, AccessSpecifier AS,
2570                                               DeclSpecContext DSContext,
2571                                               LateParsedAttrList *LateAttrs) {
2572   assert(DS.hasTagDefinition() && "shouldn't call this");
2573 
2574   bool EnteringContext = (DSContext == DSC_class || DSContext == DSC_top_level);
2575 
2576   if (getLangOpts().CPlusPlus &&
2577       Tok.isOneOf(tok::identifier, tok::coloncolon, tok::kw_decltype,
2578                   tok::annot_template_id) &&
2579       TryAnnotateCXXScopeToken(EnteringContext)) {
2580     SkipMalformedDecl();
2581     return true;
2582   }
2583 
2584   bool HasScope = Tok.is(tok::annot_cxxscope);
2585   // Make a copy in case GetLookAheadToken invalidates the result of NextToken.
2586   Token AfterScope = HasScope ? NextToken() : Tok;
2587 
2588   // Determine whether the following tokens could possibly be a
2589   // declarator.
2590   bool MightBeDeclarator = true;
2591   if (Tok.isOneOf(tok::kw_typename, tok::annot_typename)) {
2592     // A declarator-id can't start with 'typename'.
2593     MightBeDeclarator = false;
2594   } else if (AfterScope.is(tok::annot_template_id)) {
2595     // If we have a type expressed as a template-id, this cannot be a
2596     // declarator-id (such a type cannot be redeclared in a simple-declaration).
2597     TemplateIdAnnotation *Annot =
2598         static_cast<TemplateIdAnnotation *>(AfterScope.getAnnotationValue());
2599     if (Annot->Kind == TNK_Type_template)
2600       MightBeDeclarator = false;
2601   } else if (AfterScope.is(tok::identifier)) {
2602     const Token &Next = HasScope ? GetLookAheadToken(2) : NextToken();
2603 
2604     // These tokens cannot come after the declarator-id in a
2605     // simple-declaration, and are likely to come after a type-specifier.
2606     if (Next.isOneOf(tok::star, tok::amp, tok::ampamp, tok::identifier,
2607                      tok::annot_cxxscope, tok::coloncolon)) {
2608       // Missing a semicolon.
2609       MightBeDeclarator = false;
2610     } else if (HasScope) {
2611       // If the declarator-id has a scope specifier, it must redeclare a
2612       // previously-declared entity. If that's a type (and this is not a
2613       // typedef), that's an error.
2614       CXXScopeSpec SS;
2615       Actions.RestoreNestedNameSpecifierAnnotation(
2616           Tok.getAnnotationValue(), Tok.getAnnotationRange(), SS);
2617       IdentifierInfo *Name = AfterScope.getIdentifierInfo();
2618       Sema::NameClassification Classification = Actions.ClassifyName(
2619           getCurScope(), SS, Name, AfterScope.getLocation(), Next,
2620           /*IsAddressOfOperand*/false);
2621       switch (Classification.getKind()) {
2622       case Sema::NC_Error:
2623         SkipMalformedDecl();
2624         return true;
2625 
2626       case Sema::NC_Keyword:
2627       case Sema::NC_NestedNameSpecifier:
2628         llvm_unreachable("typo correction and nested name specifiers not "
2629                          "possible here");
2630 
2631       case Sema::NC_Type:
2632       case Sema::NC_TypeTemplate:
2633         // Not a previously-declared non-type entity.
2634         MightBeDeclarator = false;
2635         break;
2636 
2637       case Sema::NC_Unknown:
2638       case Sema::NC_Expression:
2639       case Sema::NC_VarTemplate:
2640       case Sema::NC_FunctionTemplate:
2641         // Might be a redeclaration of a prior entity.
2642         break;
2643       }
2644     }
2645   }
2646 
2647   if (MightBeDeclarator)
2648     return false;
2649 
2650   const PrintingPolicy &PPol = Actions.getASTContext().getPrintingPolicy();
2651   Diag(PP.getLocForEndOfToken(DS.getRepAsDecl()->getLocEnd()),
2652        diag::err_expected_after)
2653       << DeclSpec::getSpecifierName(DS.getTypeSpecType(), PPol) << tok::semi;
2654 
2655   // Try to recover from the typo, by dropping the tag definition and parsing
2656   // the problematic tokens as a type.
2657   //
2658   // FIXME: Split the DeclSpec into pieces for the standalone
2659   // declaration and pieces for the following declaration, instead
2660   // of assuming that all the other pieces attach to new declaration,
2661   // and call ParsedFreeStandingDeclSpec as appropriate.
2662   DS.ClearTypeSpecType();
2663   ParsedTemplateInfo NotATemplate;
2664   ParseDeclarationSpecifiers(DS, NotATemplate, AS, DSContext, LateAttrs);
2665   return false;
2666 }
2667 
2668 /// ParseDeclarationSpecifiers
2669 ///       declaration-specifiers: [C99 6.7]
2670 ///         storage-class-specifier declaration-specifiers[opt]
2671 ///         type-specifier declaration-specifiers[opt]
2672 /// [C99]   function-specifier declaration-specifiers[opt]
2673 /// [C11]   alignment-specifier declaration-specifiers[opt]
2674 /// [GNU]   attributes declaration-specifiers[opt]
2675 /// [Clang] '__module_private__' declaration-specifiers[opt]
2676 /// [ObjC1] '__kindof' declaration-specifiers[opt]
2677 ///
2678 ///       storage-class-specifier: [C99 6.7.1]
2679 ///         'typedef'
2680 ///         'extern'
2681 ///         'static'
2682 ///         'auto'
2683 ///         'register'
2684 /// [C++]   'mutable'
2685 /// [C++11] 'thread_local'
2686 /// [C11]   '_Thread_local'
2687 /// [GNU]   '__thread'
2688 ///       function-specifier: [C99 6.7.4]
2689 /// [C99]   'inline'
2690 /// [C++]   'virtual'
2691 /// [C++]   'explicit'
2692 /// [OpenCL] '__kernel'
2693 ///       'friend': [C++ dcl.friend]
2694 ///       'constexpr': [C++0x dcl.constexpr]
2695 void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
2696                                         const ParsedTemplateInfo &TemplateInfo,
2697                                         AccessSpecifier AS,
2698                                         DeclSpecContext DSContext,
2699                                         LateParsedAttrList *LateAttrs) {
2700   if (DS.getSourceRange().isInvalid()) {
2701     // Start the range at the current token but make the end of the range
2702     // invalid.  This will make the entire range invalid unless we successfully
2703     // consume a token.
2704     DS.SetRangeStart(Tok.getLocation());
2705     DS.SetRangeEnd(SourceLocation());
2706   }
2707 
2708   bool EnteringContext = (DSContext == DSC_class || DSContext == DSC_top_level);
2709   bool AttrsLastTime = false;
2710   ParsedAttributesWithRange attrs(AttrFactory);
2711   // We use Sema's policy to get bool macros right.
2712   PrintingPolicy Policy = Actions.getPrintingPolicy();
2713   while (1) {
2714     bool isInvalid = false;
2715     bool isStorageClass = false;
2716     const char *PrevSpec = nullptr;
2717     unsigned DiagID = 0;
2718 
2719     // HACK: MSVC doesn't consider _Atomic to be a keyword and its STL
2720     // implementation for VS2013 uses _Atomic as an identifier for one of the
2721     // classes in <atomic>.
2722     //
2723     // A typedef declaration containing _Atomic<...> is among the places where
2724     // the class is used.  If we are currently parsing such a declaration, treat
2725     // the token as an identifier.
2726     if (getLangOpts().MSVCCompat && Tok.is(tok::kw__Atomic) &&
2727         DS.getStorageClassSpec() == clang::DeclSpec::SCS_typedef &&
2728         !DS.hasTypeSpecifier() && GetLookAheadToken(1).is(tok::less))
2729       Tok.setKind(tok::identifier);
2730 
2731     SourceLocation Loc = Tok.getLocation();
2732 
2733     switch (Tok.getKind()) {
2734     default:
2735     DoneWithDeclSpec:
2736       if (!AttrsLastTime)
2737         ProhibitAttributes(attrs);
2738       else {
2739         // Reject C++11 attributes that appertain to decl specifiers as
2740         // we don't support any C++11 attributes that appertain to decl
2741         // specifiers. This also conforms to what g++ 4.8 is doing.
2742         ProhibitCXX11Attributes(attrs, diag::err_attribute_not_type_attr);
2743 
2744         DS.takeAttributesFrom(attrs);
2745       }
2746 
2747       // If this is not a declaration specifier token, we're done reading decl
2748       // specifiers.  First verify that DeclSpec's are consistent.
2749       DS.Finish(Actions, Policy);
2750       return;
2751 
2752     case tok::l_square:
2753     case tok::kw_alignas:
2754       if (!getLangOpts().CPlusPlus11 || !isCXX11AttributeSpecifier())
2755         goto DoneWithDeclSpec;
2756 
2757       ProhibitAttributes(attrs);
2758       // FIXME: It would be good to recover by accepting the attributes,
2759       //        but attempting to do that now would cause serious
2760       //        madness in terms of diagnostics.
2761       attrs.clear();
2762       attrs.Range = SourceRange();
2763 
2764       ParseCXX11Attributes(attrs);
2765       AttrsLastTime = true;
2766       continue;
2767 
2768     case tok::code_completion: {
2769       Sema::ParserCompletionContext CCC = Sema::PCC_Namespace;
2770       if (DS.hasTypeSpecifier()) {
2771         bool AllowNonIdentifiers
2772           = (getCurScope()->getFlags() & (Scope::ControlScope |
2773                                           Scope::BlockScope |
2774                                           Scope::TemplateParamScope |
2775                                           Scope::FunctionPrototypeScope |
2776                                           Scope::AtCatchScope)) == 0;
2777         bool AllowNestedNameSpecifiers
2778           = DSContext == DSC_top_level ||
2779             (DSContext == DSC_class && DS.isFriendSpecified());
2780 
2781         Actions.CodeCompleteDeclSpec(getCurScope(), DS,
2782                                      AllowNonIdentifiers,
2783                                      AllowNestedNameSpecifiers);
2784         return cutOffParsing();
2785       }
2786 
2787       if (getCurScope()->getFnParent() || getCurScope()->getBlockParent())
2788         CCC = Sema::PCC_LocalDeclarationSpecifiers;
2789       else if (TemplateInfo.Kind != ParsedTemplateInfo::NonTemplate)
2790         CCC = DSContext == DSC_class? Sema::PCC_MemberTemplate
2791                                     : Sema::PCC_Template;
2792       else if (DSContext == DSC_class)
2793         CCC = Sema::PCC_Class;
2794       else if (CurParsedObjCImpl)
2795         CCC = Sema::PCC_ObjCImplementation;
2796 
2797       Actions.CodeCompleteOrdinaryName(getCurScope(), CCC);
2798       return cutOffParsing();
2799     }
2800 
2801     case tok::coloncolon: // ::foo::bar
2802       // C++ scope specifier.  Annotate and loop, or bail out on error.
2803       if (TryAnnotateCXXScopeToken(EnteringContext)) {
2804         if (!DS.hasTypeSpecifier())
2805           DS.SetTypeSpecError();
2806         goto DoneWithDeclSpec;
2807       }
2808       if (Tok.is(tok::coloncolon)) // ::new or ::delete
2809         goto DoneWithDeclSpec;
2810       continue;
2811 
2812     case tok::annot_cxxscope: {
2813       if (DS.hasTypeSpecifier() || DS.isTypeAltiVecVector())
2814         goto DoneWithDeclSpec;
2815 
2816       CXXScopeSpec SS;
2817       Actions.RestoreNestedNameSpecifierAnnotation(Tok.getAnnotationValue(),
2818                                                    Tok.getAnnotationRange(),
2819                                                    SS);
2820 
2821       // We are looking for a qualified typename.
2822       Token Next = NextToken();
2823       if (Next.is(tok::annot_template_id) &&
2824           static_cast<TemplateIdAnnotation *>(Next.getAnnotationValue())
2825             ->Kind == TNK_Type_template) {
2826         // We have a qualified template-id, e.g., N::A<int>
2827 
2828         // C++ [class.qual]p2:
2829         //   In a lookup in which the constructor is an acceptable lookup
2830         //   result and the nested-name-specifier nominates a class C:
2831         //
2832         //     - if the name specified after the
2833         //       nested-name-specifier, when looked up in C, is the
2834         //       injected-class-name of C (Clause 9), or
2835         //
2836         //     - if the name specified after the nested-name-specifier
2837         //       is the same as the identifier or the
2838         //       simple-template-id's template-name in the last
2839         //       component of the nested-name-specifier,
2840         //
2841         //   the name is instead considered to name the constructor of
2842         //   class C.
2843         //
2844         // Thus, if the template-name is actually the constructor
2845         // name, then the code is ill-formed; this interpretation is
2846         // reinforced by the NAD status of core issue 635.
2847         TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Next);
2848         if ((DSContext == DSC_top_level || DSContext == DSC_class) &&
2849             TemplateId->Name &&
2850             Actions.isCurrentClassName(*TemplateId->Name, getCurScope(), &SS)) {
2851           if (isConstructorDeclarator(/*Unqualified*/false)) {
2852             // The user meant this to be an out-of-line constructor
2853             // definition, but template arguments are not allowed
2854             // there.  Just allow this as a constructor; we'll
2855             // complain about it later.
2856             goto DoneWithDeclSpec;
2857           }
2858 
2859           // The user meant this to name a type, but it actually names
2860           // a constructor with some extraneous template
2861           // arguments. Complain, then parse it as a type as the user
2862           // intended.
2863           Diag(TemplateId->TemplateNameLoc,
2864                diag::err_out_of_line_template_id_type_names_constructor)
2865             << TemplateId->Name << 0 /* template name */;
2866         }
2867 
2868         DS.getTypeSpecScope() = SS;
2869         ConsumeToken(); // The C++ scope.
2870         assert(Tok.is(tok::annot_template_id) &&
2871                "ParseOptionalCXXScopeSpecifier not working");
2872         AnnotateTemplateIdTokenAsType();
2873         continue;
2874       }
2875 
2876       if (Next.is(tok::annot_typename)) {
2877         DS.getTypeSpecScope() = SS;
2878         ConsumeToken(); // The C++ scope.
2879         if (Tok.getAnnotationValue()) {
2880           ParsedType T = getTypeAnnotation(Tok);
2881           isInvalid = DS.SetTypeSpecType(DeclSpec::TST_typename,
2882                                          Tok.getAnnotationEndLoc(),
2883                                          PrevSpec, DiagID, T, Policy);
2884           if (isInvalid)
2885             break;
2886         }
2887         else
2888           DS.SetTypeSpecError();
2889         DS.SetRangeEnd(Tok.getAnnotationEndLoc());
2890         ConsumeToken(); // The typename
2891       }
2892 
2893       if (Next.isNot(tok::identifier))
2894         goto DoneWithDeclSpec;
2895 
2896       // If we're in a context where the identifier could be a class name,
2897       // check whether this is a constructor declaration.
2898       if ((DSContext == DSC_top_level || DSContext == DSC_class) &&
2899           Actions.isCurrentClassName(*Next.getIdentifierInfo(), getCurScope(),
2900                                      &SS)) {
2901         if (isConstructorDeclarator(/*Unqualified*/false))
2902           goto DoneWithDeclSpec;
2903 
2904         // As noted in C++ [class.qual]p2 (cited above), when the name
2905         // of the class is qualified in a context where it could name
2906         // a constructor, its a constructor name. However, we've
2907         // looked at the declarator, and the user probably meant this
2908         // to be a type. Complain that it isn't supposed to be treated
2909         // as a type, then proceed to parse it as a type.
2910         Diag(Next.getLocation(),
2911              diag::err_out_of_line_template_id_type_names_constructor)
2912           << Next.getIdentifierInfo() << 1 /* type */;
2913       }
2914 
2915       ParsedType TypeRep =
2916           Actions.getTypeName(*Next.getIdentifierInfo(), Next.getLocation(),
2917                               getCurScope(), &SS, false, false, nullptr,
2918                               /*IsCtorOrDtorName=*/false,
2919                               /*NonTrivialSourceInfo=*/true);
2920 
2921       // If the referenced identifier is not a type, then this declspec is
2922       // erroneous: We already checked about that it has no type specifier, and
2923       // C++ doesn't have implicit int.  Diagnose it as a typo w.r.t. to the
2924       // typename.
2925       if (!TypeRep) {
2926         ConsumeToken();   // Eat the scope spec so the identifier is current.
2927         ParsedAttributesWithRange Attrs(AttrFactory);
2928         if (ParseImplicitInt(DS, &SS, TemplateInfo, AS, DSContext, Attrs)) {
2929           if (!Attrs.empty()) {
2930             AttrsLastTime = true;
2931             attrs.takeAllFrom(Attrs);
2932           }
2933           continue;
2934         }
2935         goto DoneWithDeclSpec;
2936       }
2937 
2938       DS.getTypeSpecScope() = SS;
2939       ConsumeToken(); // The C++ scope.
2940 
2941       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_typename, Loc, PrevSpec,
2942                                      DiagID, TypeRep, Policy);
2943       if (isInvalid)
2944         break;
2945 
2946       DS.SetRangeEnd(Tok.getLocation());
2947       ConsumeToken(); // The typename.
2948 
2949       continue;
2950     }
2951 
2952     case tok::annot_typename: {
2953       // If we've previously seen a tag definition, we were almost surely
2954       // missing a semicolon after it.
2955       if (DS.hasTypeSpecifier() && DS.hasTagDefinition())
2956         goto DoneWithDeclSpec;
2957 
2958       if (Tok.getAnnotationValue()) {
2959         ParsedType T = getTypeAnnotation(Tok);
2960         isInvalid = DS.SetTypeSpecType(DeclSpec::TST_typename, Loc, PrevSpec,
2961                                        DiagID, T, Policy);
2962       } else
2963         DS.SetTypeSpecError();
2964 
2965       if (isInvalid)
2966         break;
2967 
2968       DS.SetRangeEnd(Tok.getAnnotationEndLoc());
2969       ConsumeToken(); // The typename
2970 
2971       continue;
2972     }
2973 
2974     case tok::kw___is_signed:
2975       // GNU libstdc++ 4.4 uses __is_signed as an identifier, but Clang
2976       // typically treats it as a trait. If we see __is_signed as it appears
2977       // in libstdc++, e.g.,
2978       //
2979       //   static const bool __is_signed;
2980       //
2981       // then treat __is_signed as an identifier rather than as a keyword.
2982       if (DS.getTypeSpecType() == TST_bool &&
2983           DS.getTypeQualifiers() == DeclSpec::TQ_const &&
2984           DS.getStorageClassSpec() == DeclSpec::SCS_static)
2985         TryKeywordIdentFallback(true);
2986 
2987       // We're done with the declaration-specifiers.
2988       goto DoneWithDeclSpec;
2989 
2990       // typedef-name
2991     case tok::kw___super:
2992     case tok::kw_decltype:
2993     case tok::identifier: {
2994       // This identifier can only be a typedef name if we haven't already seen
2995       // a type-specifier.  Without this check we misparse:
2996       //  typedef int X; struct Y { short X; };  as 'short int'.
2997       if (DS.hasTypeSpecifier())
2998         goto DoneWithDeclSpec;
2999 
3000       // In C++, check to see if this is a scope specifier like foo::bar::, if
3001       // so handle it as such.  This is important for ctor parsing.
3002       if (getLangOpts().CPlusPlus) {
3003         if (TryAnnotateCXXScopeToken(EnteringContext)) {
3004           DS.SetTypeSpecError();
3005           goto DoneWithDeclSpec;
3006         }
3007         if (!Tok.is(tok::identifier))
3008           continue;
3009       }
3010 
3011       // Check for need to substitute AltiVec keyword tokens.
3012       if (TryAltiVecToken(DS, Loc, PrevSpec, DiagID, isInvalid))
3013         break;
3014 
3015       // [AltiVec] 2.2: [If the 'vector' specifier is used] The syntax does not
3016       //                allow the use of a typedef name as a type specifier.
3017       if (DS.isTypeAltiVecVector())
3018         goto DoneWithDeclSpec;
3019 
3020       if (DSContext == DSC_objc_method_result && isObjCInstancetype()) {
3021         ParsedType TypeRep = Actions.ActOnObjCInstanceType(Loc);
3022         assert(TypeRep);
3023         isInvalid = DS.SetTypeSpecType(DeclSpec::TST_typename, Loc, PrevSpec,
3024                                        DiagID, TypeRep, Policy);
3025         if (isInvalid)
3026           break;
3027 
3028         DS.SetRangeEnd(Loc);
3029         ConsumeToken();
3030         continue;
3031       }
3032 
3033       ParsedType TypeRep =
3034         Actions.getTypeName(*Tok.getIdentifierInfo(),
3035                             Tok.getLocation(), getCurScope());
3036 
3037       // If this is not a typedef name, don't parse it as part of the declspec,
3038       // it must be an implicit int or an error.
3039       if (!TypeRep) {
3040         ParsedAttributesWithRange Attrs(AttrFactory);
3041         if (ParseImplicitInt(DS, nullptr, TemplateInfo, AS, DSContext, Attrs)) {
3042           if (!Attrs.empty()) {
3043             AttrsLastTime = true;
3044             attrs.takeAllFrom(Attrs);
3045           }
3046           continue;
3047         }
3048         goto DoneWithDeclSpec;
3049       }
3050 
3051       // If we're in a context where the identifier could be a class name,
3052       // check whether this is a constructor declaration.
3053       if (getLangOpts().CPlusPlus && DSContext == DSC_class &&
3054           Actions.isCurrentClassName(*Tok.getIdentifierInfo(), getCurScope()) &&
3055           isConstructorDeclarator(/*Unqualified*/true))
3056         goto DoneWithDeclSpec;
3057 
3058       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_typename, Loc, PrevSpec,
3059                                      DiagID, TypeRep, Policy);
3060       if (isInvalid)
3061         break;
3062 
3063       DS.SetRangeEnd(Tok.getLocation());
3064       ConsumeToken(); // The identifier
3065 
3066       // Objective-C supports type arguments and protocol references
3067       // following an Objective-C object or object pointer
3068       // type. Handle either one of them.
3069       if (Tok.is(tok::less) && getLangOpts().ObjC1) {
3070         SourceLocation NewEndLoc;
3071         TypeResult NewTypeRep = parseObjCTypeArgsAndProtocolQualifiers(
3072                                   Loc, TypeRep, /*consumeLastToken=*/true,
3073                                   NewEndLoc);
3074         if (NewTypeRep.isUsable()) {
3075           DS.UpdateTypeRep(NewTypeRep.get());
3076           DS.SetRangeEnd(NewEndLoc);
3077         }
3078       }
3079 
3080       // Need to support trailing type qualifiers (e.g. "id<p> const").
3081       // If a type specifier follows, it will be diagnosed elsewhere.
3082       continue;
3083     }
3084 
3085       // type-name
3086     case tok::annot_template_id: {
3087       TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok);
3088       if (TemplateId->Kind != TNK_Type_template) {
3089         // This template-id does not refer to a type name, so we're
3090         // done with the type-specifiers.
3091         goto DoneWithDeclSpec;
3092       }
3093 
3094       // If we're in a context where the template-id could be a
3095       // constructor name or specialization, check whether this is a
3096       // constructor declaration.
3097       if (getLangOpts().CPlusPlus && DSContext == DSC_class &&
3098           Actions.isCurrentClassName(*TemplateId->Name, getCurScope()) &&
3099           isConstructorDeclarator(TemplateId->SS.isEmpty()))
3100         goto DoneWithDeclSpec;
3101 
3102       // Turn the template-id annotation token into a type annotation
3103       // token, then try again to parse it as a type-specifier.
3104       AnnotateTemplateIdTokenAsType();
3105       continue;
3106     }
3107 
3108     // GNU attributes support.
3109     case tok::kw___attribute:
3110       ParseGNUAttributes(DS.getAttributes(), nullptr, LateAttrs);
3111       continue;
3112 
3113     // Microsoft declspec support.
3114     case tok::kw___declspec:
3115       ParseMicrosoftDeclSpecs(DS.getAttributes());
3116       continue;
3117 
3118     // Microsoft single token adornments.
3119     case tok::kw___forceinline: {
3120       isInvalid = DS.setFunctionSpecForceInline(Loc, PrevSpec, DiagID);
3121       IdentifierInfo *AttrName = Tok.getIdentifierInfo();
3122       SourceLocation AttrNameLoc = Tok.getLocation();
3123       DS.getAttributes().addNew(AttrName, AttrNameLoc, nullptr, AttrNameLoc,
3124                                 nullptr, 0, AttributeList::AS_Keyword);
3125       break;
3126     }
3127 
3128     case tok::kw___unaligned:
3129       isInvalid = DS.SetTypeQual(DeclSpec::TQ_unaligned, Loc, PrevSpec, DiagID,
3130                                  getLangOpts());
3131       break;
3132 
3133     case tok::kw___sptr:
3134     case tok::kw___uptr:
3135     case tok::kw___ptr64:
3136     case tok::kw___ptr32:
3137     case tok::kw___w64:
3138     case tok::kw___cdecl:
3139     case tok::kw___stdcall:
3140     case tok::kw___fastcall:
3141     case tok::kw___thiscall:
3142     case tok::kw___regcall:
3143     case tok::kw___vectorcall:
3144       ParseMicrosoftTypeAttributes(DS.getAttributes());
3145       continue;
3146 
3147     // Borland single token adornments.
3148     case tok::kw___pascal:
3149       ParseBorlandTypeAttributes(DS.getAttributes());
3150       continue;
3151 
3152     // OpenCL single token adornments.
3153     case tok::kw___kernel:
3154       ParseOpenCLKernelAttributes(DS.getAttributes());
3155       continue;
3156 
3157     // Nullability type specifiers.
3158     case tok::kw__Nonnull:
3159     case tok::kw__Nullable:
3160     case tok::kw__Null_unspecified:
3161       ParseNullabilityTypeSpecifiers(DS.getAttributes());
3162       continue;
3163 
3164     // Objective-C 'kindof' types.
3165     case tok::kw___kindof:
3166       DS.getAttributes().addNew(Tok.getIdentifierInfo(), Loc, nullptr, Loc,
3167                                 nullptr, 0, AttributeList::AS_Keyword);
3168       (void)ConsumeToken();
3169       continue;
3170 
3171     // storage-class-specifier
3172     case tok::kw_typedef:
3173       isInvalid = DS.SetStorageClassSpec(Actions, DeclSpec::SCS_typedef, Loc,
3174                                          PrevSpec, DiagID, Policy);
3175       isStorageClass = true;
3176       break;
3177     case tok::kw_extern:
3178       if (DS.getThreadStorageClassSpec() == DeclSpec::TSCS___thread)
3179         Diag(Tok, diag::ext_thread_before) << "extern";
3180       isInvalid = DS.SetStorageClassSpec(Actions, DeclSpec::SCS_extern, Loc,
3181                                          PrevSpec, DiagID, Policy);
3182       isStorageClass = true;
3183       break;
3184     case tok::kw___private_extern__:
3185       isInvalid = DS.SetStorageClassSpec(Actions, DeclSpec::SCS_private_extern,
3186                                          Loc, PrevSpec, DiagID, Policy);
3187       isStorageClass = true;
3188       break;
3189     case tok::kw_static:
3190       if (DS.getThreadStorageClassSpec() == DeclSpec::TSCS___thread)
3191         Diag(Tok, diag::ext_thread_before) << "static";
3192       isInvalid = DS.SetStorageClassSpec(Actions, DeclSpec::SCS_static, Loc,
3193                                          PrevSpec, DiagID, Policy);
3194       isStorageClass = true;
3195       break;
3196     case tok::kw_auto:
3197       if (getLangOpts().CPlusPlus11) {
3198         if (isKnownToBeTypeSpecifier(GetLookAheadToken(1))) {
3199           isInvalid = DS.SetStorageClassSpec(Actions, DeclSpec::SCS_auto, Loc,
3200                                              PrevSpec, DiagID, Policy);
3201           if (!isInvalid)
3202             Diag(Tok, diag::ext_auto_storage_class)
3203               << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
3204         } else
3205           isInvalid = DS.SetTypeSpecType(DeclSpec::TST_auto, Loc, PrevSpec,
3206                                          DiagID, Policy);
3207       } else
3208         isInvalid = DS.SetStorageClassSpec(Actions, DeclSpec::SCS_auto, Loc,
3209                                            PrevSpec, DiagID, Policy);
3210       isStorageClass = true;
3211       break;
3212     case tok::kw___auto_type:
3213       Diag(Tok, diag::ext_auto_type);
3214       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_auto_type, Loc, PrevSpec,
3215                                      DiagID, Policy);
3216       break;
3217     case tok::kw_register:
3218       isInvalid = DS.SetStorageClassSpec(Actions, DeclSpec::SCS_register, Loc,
3219                                          PrevSpec, DiagID, Policy);
3220       isStorageClass = true;
3221       break;
3222     case tok::kw_mutable:
3223       isInvalid = DS.SetStorageClassSpec(Actions, DeclSpec::SCS_mutable, Loc,
3224                                          PrevSpec, DiagID, Policy);
3225       isStorageClass = true;
3226       break;
3227     case tok::kw___thread:
3228       isInvalid = DS.SetStorageClassSpecThread(DeclSpec::TSCS___thread, Loc,
3229                                                PrevSpec, DiagID);
3230       isStorageClass = true;
3231       break;
3232     case tok::kw_thread_local:
3233       isInvalid = DS.SetStorageClassSpecThread(DeclSpec::TSCS_thread_local, Loc,
3234                                                PrevSpec, DiagID);
3235       break;
3236     case tok::kw__Thread_local:
3237       isInvalid = DS.SetStorageClassSpecThread(DeclSpec::TSCS__Thread_local,
3238                                                Loc, PrevSpec, DiagID);
3239       isStorageClass = true;
3240       break;
3241 
3242     // function-specifier
3243     case tok::kw_inline:
3244       isInvalid = DS.setFunctionSpecInline(Loc, PrevSpec, DiagID);
3245       break;
3246     case tok::kw_virtual:
3247       isInvalid = DS.setFunctionSpecVirtual(Loc, PrevSpec, DiagID);
3248       break;
3249     case tok::kw_explicit:
3250       isInvalid = DS.setFunctionSpecExplicit(Loc, PrevSpec, DiagID);
3251       break;
3252     case tok::kw__Noreturn:
3253       if (!getLangOpts().C11)
3254         Diag(Loc, diag::ext_c11_noreturn);
3255       isInvalid = DS.setFunctionSpecNoreturn(Loc, PrevSpec, DiagID);
3256       break;
3257 
3258     // alignment-specifier
3259     case tok::kw__Alignas:
3260       if (!getLangOpts().C11)
3261         Diag(Tok, diag::ext_c11_alignment) << Tok.getName();
3262       ParseAlignmentSpecifier(DS.getAttributes());
3263       continue;
3264 
3265     // friend
3266     case tok::kw_friend:
3267       if (DSContext == DSC_class)
3268         isInvalid = DS.SetFriendSpec(Loc, PrevSpec, DiagID);
3269       else {
3270         PrevSpec = ""; // not actually used by the diagnostic
3271         DiagID = diag::err_friend_invalid_in_context;
3272         isInvalid = true;
3273       }
3274       break;
3275 
3276     // Modules
3277     case tok::kw___module_private__:
3278       isInvalid = DS.setModulePrivateSpec(Loc, PrevSpec, DiagID);
3279       break;
3280 
3281     // constexpr
3282     case tok::kw_constexpr:
3283       isInvalid = DS.SetConstexprSpec(Loc, PrevSpec, DiagID);
3284       break;
3285 
3286     // concept
3287     case tok::kw_concept:
3288       isInvalid = DS.SetConceptSpec(Loc, PrevSpec, DiagID);
3289       break;
3290 
3291     // type-specifier
3292     case tok::kw_short:
3293       isInvalid = DS.SetTypeSpecWidth(DeclSpec::TSW_short, Loc, PrevSpec,
3294                                       DiagID, Policy);
3295       break;
3296     case tok::kw_long:
3297       if (DS.getTypeSpecWidth() != DeclSpec::TSW_long)
3298         isInvalid = DS.SetTypeSpecWidth(DeclSpec::TSW_long, Loc, PrevSpec,
3299                                         DiagID, Policy);
3300       else
3301         isInvalid = DS.SetTypeSpecWidth(DeclSpec::TSW_longlong, Loc, PrevSpec,
3302                                         DiagID, Policy);
3303       break;
3304     case tok::kw___int64:
3305         isInvalid = DS.SetTypeSpecWidth(DeclSpec::TSW_longlong, Loc, PrevSpec,
3306                                         DiagID, Policy);
3307       break;
3308     case tok::kw_signed:
3309       isInvalid = DS.SetTypeSpecSign(DeclSpec::TSS_signed, Loc, PrevSpec,
3310                                      DiagID);
3311       break;
3312     case tok::kw_unsigned:
3313       isInvalid = DS.SetTypeSpecSign(DeclSpec::TSS_unsigned, Loc, PrevSpec,
3314                                      DiagID);
3315       break;
3316     case tok::kw__Complex:
3317       isInvalid = DS.SetTypeSpecComplex(DeclSpec::TSC_complex, Loc, PrevSpec,
3318                                         DiagID);
3319       break;
3320     case tok::kw__Imaginary:
3321       isInvalid = DS.SetTypeSpecComplex(DeclSpec::TSC_imaginary, Loc, PrevSpec,
3322                                         DiagID);
3323       break;
3324     case tok::kw_void:
3325       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_void, Loc, PrevSpec,
3326                                      DiagID, Policy);
3327       break;
3328     case tok::kw_char:
3329       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_char, Loc, PrevSpec,
3330                                      DiagID, Policy);
3331       break;
3332     case tok::kw_int:
3333       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, PrevSpec,
3334                                      DiagID, Policy);
3335       break;
3336     case tok::kw___int128:
3337       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_int128, Loc, PrevSpec,
3338                                      DiagID, Policy);
3339       break;
3340     case tok::kw_half:
3341       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_half, Loc, PrevSpec,
3342                                      DiagID, Policy);
3343       break;
3344     case tok::kw_float:
3345       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_float, Loc, PrevSpec,
3346                                      DiagID, Policy);
3347       break;
3348     case tok::kw_double:
3349       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_double, Loc, PrevSpec,
3350                                      DiagID, Policy);
3351       break;
3352     case tok::kw___float128:
3353       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_float128, Loc, PrevSpec,
3354                                      DiagID, Policy);
3355       break;
3356     case tok::kw_wchar_t:
3357       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_wchar, Loc, PrevSpec,
3358                                      DiagID, Policy);
3359       break;
3360     case tok::kw_char16_t:
3361       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_char16, Loc, PrevSpec,
3362                                      DiagID, Policy);
3363       break;
3364     case tok::kw_char32_t:
3365       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_char32, Loc, PrevSpec,
3366                                      DiagID, Policy);
3367       break;
3368     case tok::kw_bool:
3369     case tok::kw__Bool:
3370       if (Tok.is(tok::kw_bool) &&
3371           DS.getTypeSpecType() != DeclSpec::TST_unspecified &&
3372           DS.getStorageClassSpec() == DeclSpec::SCS_typedef) {
3373         PrevSpec = ""; // Not used by the diagnostic.
3374         DiagID = diag::err_bool_redeclaration;
3375         // For better error recovery.
3376         Tok.setKind(tok::identifier);
3377         isInvalid = true;
3378       } else {
3379         isInvalid = DS.SetTypeSpecType(DeclSpec::TST_bool, Loc, PrevSpec,
3380                                        DiagID, Policy);
3381       }
3382       break;
3383     case tok::kw__Decimal32:
3384       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_decimal32, Loc, PrevSpec,
3385                                      DiagID, Policy);
3386       break;
3387     case tok::kw__Decimal64:
3388       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_decimal64, Loc, PrevSpec,
3389                                      DiagID, Policy);
3390       break;
3391     case tok::kw__Decimal128:
3392       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_decimal128, Loc, PrevSpec,
3393                                      DiagID, Policy);
3394       break;
3395     case tok::kw___vector:
3396       isInvalid = DS.SetTypeAltiVecVector(true, Loc, PrevSpec, DiagID, Policy);
3397       break;
3398     case tok::kw___pixel:
3399       isInvalid = DS.SetTypeAltiVecPixel(true, Loc, PrevSpec, DiagID, Policy);
3400       break;
3401     case tok::kw___bool:
3402       isInvalid = DS.SetTypeAltiVecBool(true, Loc, PrevSpec, DiagID, Policy);
3403       break;
3404     case tok::kw_pipe:
3405       if (!getLangOpts().OpenCL || (getLangOpts().OpenCLVersion < 200)) {
3406         // OpenCL 2.0 defined this keyword. OpenCL 1.2 and earlier should
3407         // support the "pipe" word as identifier.
3408         Tok.getIdentifierInfo()->revertTokenIDToIdentifier();
3409         goto DoneWithDeclSpec;
3410       }
3411       isInvalid = DS.SetTypePipe(true, Loc, PrevSpec, DiagID, Policy);
3412       break;
3413 #define GENERIC_IMAGE_TYPE(ImgType, Id) \
3414   case tok::kw_##ImgType##_t: \
3415     isInvalid = DS.SetTypeSpecType(DeclSpec::TST_##ImgType##_t, Loc, PrevSpec, \
3416                                    DiagID, Policy); \
3417     break;
3418 #include "clang/Basic/OpenCLImageTypes.def"
3419     case tok::kw___unknown_anytype:
3420       isInvalid = DS.SetTypeSpecType(TST_unknown_anytype, Loc,
3421                                      PrevSpec, DiagID, Policy);
3422       break;
3423 
3424     // class-specifier:
3425     case tok::kw_class:
3426     case tok::kw_struct:
3427     case tok::kw___interface:
3428     case tok::kw_union: {
3429       tok::TokenKind Kind = Tok.getKind();
3430       ConsumeToken();
3431 
3432       // These are attributes following class specifiers.
3433       // To produce better diagnostic, we parse them when
3434       // parsing class specifier.
3435       ParsedAttributesWithRange Attributes(AttrFactory);
3436       ParseClassSpecifier(Kind, Loc, DS, TemplateInfo, AS,
3437                           EnteringContext, DSContext, Attributes);
3438 
3439       // If there are attributes following class specifier,
3440       // take them over and handle them here.
3441       if (!Attributes.empty()) {
3442         AttrsLastTime = true;
3443         attrs.takeAllFrom(Attributes);
3444       }
3445       continue;
3446     }
3447 
3448     // enum-specifier:
3449     case tok::kw_enum:
3450       ConsumeToken();
3451       ParseEnumSpecifier(Loc, DS, TemplateInfo, AS, DSContext);
3452       continue;
3453 
3454     // cv-qualifier:
3455     case tok::kw_const:
3456       isInvalid = DS.SetTypeQual(DeclSpec::TQ_const, Loc, PrevSpec, DiagID,
3457                                  getLangOpts());
3458       break;
3459     case tok::kw_volatile:
3460       isInvalid = DS.SetTypeQual(DeclSpec::TQ_volatile, Loc, PrevSpec, DiagID,
3461                                  getLangOpts());
3462       break;
3463     case tok::kw_restrict:
3464       isInvalid = DS.SetTypeQual(DeclSpec::TQ_restrict, Loc, PrevSpec, DiagID,
3465                                  getLangOpts());
3466       break;
3467 
3468     // C++ typename-specifier:
3469     case tok::kw_typename:
3470       if (TryAnnotateTypeOrScopeToken()) {
3471         DS.SetTypeSpecError();
3472         goto DoneWithDeclSpec;
3473       }
3474       if (!Tok.is(tok::kw_typename))
3475         continue;
3476       break;
3477 
3478     // GNU typeof support.
3479     case tok::kw_typeof:
3480       ParseTypeofSpecifier(DS);
3481       continue;
3482 
3483     case tok::annot_decltype:
3484       ParseDecltypeSpecifier(DS);
3485       continue;
3486 
3487     case tok::annot_pragma_pack:
3488       HandlePragmaPack();
3489       continue;
3490 
3491     case tok::annot_pragma_ms_pragma:
3492       HandlePragmaMSPragma();
3493       continue;
3494 
3495     case tok::annot_pragma_ms_vtordisp:
3496       HandlePragmaMSVtorDisp();
3497       continue;
3498 
3499     case tok::annot_pragma_ms_pointers_to_members:
3500       HandlePragmaMSPointersToMembers();
3501       continue;
3502 
3503     case tok::kw___underlying_type:
3504       ParseUnderlyingTypeSpecifier(DS);
3505       continue;
3506 
3507     case tok::kw__Atomic:
3508       // C11 6.7.2.4/4:
3509       //   If the _Atomic keyword is immediately followed by a left parenthesis,
3510       //   it is interpreted as a type specifier (with a type name), not as a
3511       //   type qualifier.
3512       if (NextToken().is(tok::l_paren)) {
3513         ParseAtomicSpecifier(DS);
3514         continue;
3515       }
3516       isInvalid = DS.SetTypeQual(DeclSpec::TQ_atomic, Loc, PrevSpec, DiagID,
3517                                  getLangOpts());
3518       break;
3519 
3520     // OpenCL qualifiers:
3521     case tok::kw___generic:
3522       // generic address space is introduced only in OpenCL v2.0
3523       // see OpenCL C Spec v2.0 s6.5.5
3524       if (Actions.getLangOpts().OpenCLVersion < 200) {
3525         DiagID = diag::err_opencl_unknown_type_specifier;
3526         PrevSpec = Tok.getIdentifierInfo()->getNameStart();
3527         isInvalid = true;
3528         break;
3529       };
3530     case tok::kw___private:
3531     case tok::kw___global:
3532     case tok::kw___local:
3533     case tok::kw___constant:
3534     case tok::kw___read_only:
3535     case tok::kw___write_only:
3536     case tok::kw___read_write:
3537       ParseOpenCLQualifiers(DS.getAttributes());
3538       break;
3539 
3540     case tok::less:
3541       // GCC ObjC supports types like "<SomeProtocol>" as a synonym for
3542       // "id<SomeProtocol>".  This is hopelessly old fashioned and dangerous,
3543       // but we support it.
3544       if (DS.hasTypeSpecifier() || !getLangOpts().ObjC1)
3545         goto DoneWithDeclSpec;
3546 
3547       SourceLocation StartLoc = Tok.getLocation();
3548       SourceLocation EndLoc;
3549       TypeResult Type = parseObjCProtocolQualifierType(EndLoc);
3550       if (Type.isUsable()) {
3551         if (DS.SetTypeSpecType(DeclSpec::TST_typename, StartLoc, StartLoc,
3552                                PrevSpec, DiagID, Type.get(),
3553                                Actions.getASTContext().getPrintingPolicy()))
3554           Diag(StartLoc, DiagID) << PrevSpec;
3555 
3556         DS.SetRangeEnd(EndLoc);
3557       } else {
3558         DS.SetTypeSpecError();
3559       }
3560 
3561       // Need to support trailing type qualifiers (e.g. "id<p> const").
3562       // If a type specifier follows, it will be diagnosed elsewhere.
3563       continue;
3564     }
3565     // If the specifier wasn't legal, issue a diagnostic.
3566     if (isInvalid) {
3567       assert(PrevSpec && "Method did not return previous specifier!");
3568       assert(DiagID);
3569 
3570       if (DiagID == diag::ext_duplicate_declspec)
3571         Diag(Tok, DiagID)
3572           << PrevSpec << FixItHint::CreateRemoval(Tok.getLocation());
3573       else if (DiagID == diag::err_opencl_unknown_type_specifier) {
3574         const int OpenCLVer = getLangOpts().OpenCLVersion;
3575         std::string VerSpec = llvm::to_string(OpenCLVer / 100) +
3576                               std::string (".") +
3577                               llvm::to_string((OpenCLVer % 100) / 10);
3578         Diag(Tok, DiagID) << VerSpec << PrevSpec << isStorageClass;
3579       } else
3580         Diag(Tok, DiagID) << PrevSpec;
3581     }
3582 
3583     DS.SetRangeEnd(Tok.getLocation());
3584     if (DiagID != diag::err_bool_redeclaration)
3585       ConsumeToken();
3586 
3587     AttrsLastTime = false;
3588   }
3589 }
3590 
3591 /// ParseStructDeclaration - Parse a struct declaration without the terminating
3592 /// semicolon.
3593 ///
3594 ///       struct-declaration:
3595 ///         specifier-qualifier-list struct-declarator-list
3596 /// [GNU]   __extension__ struct-declaration
3597 /// [GNU]   specifier-qualifier-list
3598 ///       struct-declarator-list:
3599 ///         struct-declarator
3600 ///         struct-declarator-list ',' struct-declarator
3601 /// [GNU]   struct-declarator-list ',' attributes[opt] struct-declarator
3602 ///       struct-declarator:
3603 ///         declarator
3604 /// [GNU]   declarator attributes[opt]
3605 ///         declarator[opt] ':' constant-expression
3606 /// [GNU]   declarator[opt] ':' constant-expression attributes[opt]
3607 ///
3608 void Parser::ParseStructDeclaration(
3609     ParsingDeclSpec &DS,
3610     llvm::function_ref<void(ParsingFieldDeclarator &)> FieldsCallback) {
3611 
3612   if (Tok.is(tok::kw___extension__)) {
3613     // __extension__ silences extension warnings in the subexpression.
3614     ExtensionRAIIObject O(Diags);  // Use RAII to do this.
3615     ConsumeToken();
3616     return ParseStructDeclaration(DS, FieldsCallback);
3617   }
3618 
3619   // Parse the common specifier-qualifiers-list piece.
3620   ParseSpecifierQualifierList(DS);
3621 
3622   // If there are no declarators, this is a free-standing declaration
3623   // specifier. Let the actions module cope with it.
3624   if (Tok.is(tok::semi)) {
3625     RecordDecl *AnonRecord = nullptr;
3626     Decl *TheDecl = Actions.ParsedFreeStandingDeclSpec(getCurScope(), AS_none,
3627                                                        DS, AnonRecord);
3628     assert(!AnonRecord && "Did not expect anonymous struct or union here");
3629     DS.complete(TheDecl);
3630     return;
3631   }
3632 
3633   // Read struct-declarators until we find the semicolon.
3634   bool FirstDeclarator = true;
3635   SourceLocation CommaLoc;
3636   while (1) {
3637     ParsingFieldDeclarator DeclaratorInfo(*this, DS);
3638     DeclaratorInfo.D.setCommaLoc(CommaLoc);
3639 
3640     // Attributes are only allowed here on successive declarators.
3641     if (!FirstDeclarator)
3642       MaybeParseGNUAttributes(DeclaratorInfo.D);
3643 
3644     /// struct-declarator: declarator
3645     /// struct-declarator: declarator[opt] ':' constant-expression
3646     if (Tok.isNot(tok::colon)) {
3647       // Don't parse FOO:BAR as if it were a typo for FOO::BAR.
3648       ColonProtectionRAIIObject X(*this);
3649       ParseDeclarator(DeclaratorInfo.D);
3650     } else
3651       DeclaratorInfo.D.SetIdentifier(nullptr, Tok.getLocation());
3652 
3653     if (TryConsumeToken(tok::colon)) {
3654       ExprResult Res(ParseConstantExpression());
3655       if (Res.isInvalid())
3656         SkipUntil(tok::semi, StopBeforeMatch);
3657       else
3658         DeclaratorInfo.BitfieldSize = Res.get();
3659     }
3660 
3661     // If attributes exist after the declarator, parse them.
3662     MaybeParseGNUAttributes(DeclaratorInfo.D);
3663 
3664     // We're done with this declarator;  invoke the callback.
3665     FieldsCallback(DeclaratorInfo);
3666 
3667     // If we don't have a comma, it is either the end of the list (a ';')
3668     // or an error, bail out.
3669     if (!TryConsumeToken(tok::comma, CommaLoc))
3670       return;
3671 
3672     FirstDeclarator = false;
3673   }
3674 }
3675 
3676 /// ParseStructUnionBody
3677 ///       struct-contents:
3678 ///         struct-declaration-list
3679 /// [EXT]   empty
3680 /// [GNU]   "struct-declaration-list" without terminatoring ';'
3681 ///       struct-declaration-list:
3682 ///         struct-declaration
3683 ///         struct-declaration-list struct-declaration
3684 /// [OBC]   '@' 'defs' '(' class-name ')'
3685 ///
3686 void Parser::ParseStructUnionBody(SourceLocation RecordLoc,
3687                                   unsigned TagType, Decl *TagDecl) {
3688   PrettyDeclStackTraceEntry CrashInfo(Actions, TagDecl, RecordLoc,
3689                                       "parsing struct/union body");
3690   assert(!getLangOpts().CPlusPlus && "C++ declarations not supported");
3691 
3692   BalancedDelimiterTracker T(*this, tok::l_brace);
3693   if (T.consumeOpen())
3694     return;
3695 
3696   ParseScope StructScope(this, Scope::ClassScope|Scope::DeclScope);
3697   Actions.ActOnTagStartDefinition(getCurScope(), TagDecl);
3698 
3699   SmallVector<Decl *, 32> FieldDecls;
3700 
3701   // While we still have something to read, read the declarations in the struct.
3702   while (!tryParseMisplacedModuleImport() && Tok.isNot(tok::r_brace) &&
3703          Tok.isNot(tok::eof)) {
3704     // Each iteration of this loop reads one struct-declaration.
3705 
3706     // Check for extraneous top-level semicolon.
3707     if (Tok.is(tok::semi)) {
3708       ConsumeExtraSemi(InsideStruct, TagType);
3709       continue;
3710     }
3711 
3712     // Parse _Static_assert declaration.
3713     if (Tok.is(tok::kw__Static_assert)) {
3714       SourceLocation DeclEnd;
3715       ParseStaticAssertDeclaration(DeclEnd);
3716       continue;
3717     }
3718 
3719     if (Tok.is(tok::annot_pragma_pack)) {
3720       HandlePragmaPack();
3721       continue;
3722     }
3723 
3724     if (Tok.is(tok::annot_pragma_align)) {
3725       HandlePragmaAlign();
3726       continue;
3727     }
3728 
3729     if (Tok.is(tok::annot_pragma_openmp)) {
3730       // Result can be ignored, because it must be always empty.
3731       AccessSpecifier AS = AS_none;
3732       ParsedAttributesWithRange Attrs(AttrFactory);
3733       (void)ParseOpenMPDeclarativeDirectiveWithExtDecl(AS, Attrs);
3734       continue;
3735     }
3736 
3737     if (!Tok.is(tok::at)) {
3738       auto CFieldCallback = [&](ParsingFieldDeclarator &FD) {
3739         // Install the declarator into the current TagDecl.
3740         Decl *Field =
3741             Actions.ActOnField(getCurScope(), TagDecl,
3742                                FD.D.getDeclSpec().getSourceRange().getBegin(),
3743                                FD.D, FD.BitfieldSize);
3744         FieldDecls.push_back(Field);
3745         FD.complete(Field);
3746       };
3747 
3748       // Parse all the comma separated declarators.
3749       ParsingDeclSpec DS(*this);
3750       ParseStructDeclaration(DS, CFieldCallback);
3751     } else { // Handle @defs
3752       ConsumeToken();
3753       if (!Tok.isObjCAtKeyword(tok::objc_defs)) {
3754         Diag(Tok, diag::err_unexpected_at);
3755         SkipUntil(tok::semi);
3756         continue;
3757       }
3758       ConsumeToken();
3759       ExpectAndConsume(tok::l_paren);
3760       if (!Tok.is(tok::identifier)) {
3761         Diag(Tok, diag::err_expected) << tok::identifier;
3762         SkipUntil(tok::semi);
3763         continue;
3764       }
3765       SmallVector<Decl *, 16> Fields;
3766       Actions.ActOnDefs(getCurScope(), TagDecl, Tok.getLocation(),
3767                         Tok.getIdentifierInfo(), Fields);
3768       FieldDecls.insert(FieldDecls.end(), Fields.begin(), Fields.end());
3769       ConsumeToken();
3770       ExpectAndConsume(tok::r_paren);
3771     }
3772 
3773     if (TryConsumeToken(tok::semi))
3774       continue;
3775 
3776     if (Tok.is(tok::r_brace)) {
3777       ExpectAndConsume(tok::semi, diag::ext_expected_semi_decl_list);
3778       break;
3779     }
3780 
3781     ExpectAndConsume(tok::semi, diag::err_expected_semi_decl_list);
3782     // Skip to end of block or statement to avoid ext-warning on extra ';'.
3783     SkipUntil(tok::r_brace, StopAtSemi | StopBeforeMatch);
3784     // If we stopped at a ';', eat it.
3785     TryConsumeToken(tok::semi);
3786   }
3787 
3788   T.consumeClose();
3789 
3790   ParsedAttributes attrs(AttrFactory);
3791   // If attributes exist after struct contents, parse them.
3792   MaybeParseGNUAttributes(attrs);
3793 
3794   Actions.ActOnFields(getCurScope(),
3795                       RecordLoc, TagDecl, FieldDecls,
3796                       T.getOpenLocation(), T.getCloseLocation(),
3797                       attrs.getList());
3798   StructScope.Exit();
3799   Actions.ActOnTagFinishDefinition(getCurScope(), TagDecl, T.getRange());
3800 }
3801 
3802 /// ParseEnumSpecifier
3803 ///       enum-specifier: [C99 6.7.2.2]
3804 ///         'enum' identifier[opt] '{' enumerator-list '}'
3805 ///[C99/C++]'enum' identifier[opt] '{' enumerator-list ',' '}'
3806 /// [GNU]   'enum' attributes[opt] identifier[opt] '{' enumerator-list ',' [opt]
3807 ///                                                 '}' attributes[opt]
3808 /// [MS]    'enum' __declspec[opt] identifier[opt] '{' enumerator-list ',' [opt]
3809 ///                                                 '}'
3810 ///         'enum' identifier
3811 /// [GNU]   'enum' attributes[opt] identifier
3812 ///
3813 /// [C++11] enum-head '{' enumerator-list[opt] '}'
3814 /// [C++11] enum-head '{' enumerator-list ','  '}'
3815 ///
3816 ///       enum-head: [C++11]
3817 ///         enum-key attribute-specifier-seq[opt] identifier[opt] enum-base[opt]
3818 ///         enum-key attribute-specifier-seq[opt] nested-name-specifier
3819 ///             identifier enum-base[opt]
3820 ///
3821 ///       enum-key: [C++11]
3822 ///         'enum'
3823 ///         'enum' 'class'
3824 ///         'enum' 'struct'
3825 ///
3826 ///       enum-base: [C++11]
3827 ///         ':' type-specifier-seq
3828 ///
3829 /// [C++] elaborated-type-specifier:
3830 /// [C++]   'enum' '::'[opt] nested-name-specifier[opt] identifier
3831 ///
3832 void Parser::ParseEnumSpecifier(SourceLocation StartLoc, DeclSpec &DS,
3833                                 const ParsedTemplateInfo &TemplateInfo,
3834                                 AccessSpecifier AS, DeclSpecContext DSC) {
3835   // Parse the tag portion of this.
3836   if (Tok.is(tok::code_completion)) {
3837     // Code completion for an enum name.
3838     Actions.CodeCompleteTag(getCurScope(), DeclSpec::TST_enum);
3839     return cutOffParsing();
3840   }
3841 
3842   // If attributes exist after tag, parse them.
3843   ParsedAttributesWithRange attrs(AttrFactory);
3844   MaybeParseGNUAttributes(attrs);
3845   MaybeParseCXX11Attributes(attrs);
3846   MaybeParseMicrosoftDeclSpecs(attrs);
3847 
3848   SourceLocation ScopedEnumKWLoc;
3849   bool IsScopedUsingClassTag = false;
3850 
3851   // In C++11, recognize 'enum class' and 'enum struct'.
3852   if (Tok.isOneOf(tok::kw_class, tok::kw_struct)) {
3853     Diag(Tok, getLangOpts().CPlusPlus11 ? diag::warn_cxx98_compat_scoped_enum
3854                                         : diag::ext_scoped_enum);
3855     IsScopedUsingClassTag = Tok.is(tok::kw_class);
3856     ScopedEnumKWLoc = ConsumeToken();
3857 
3858     // Attributes are not allowed between these keywords.  Diagnose,
3859     // but then just treat them like they appeared in the right place.
3860     ProhibitAttributes(attrs);
3861 
3862     // They are allowed afterwards, though.
3863     MaybeParseGNUAttributes(attrs);
3864     MaybeParseCXX11Attributes(attrs);
3865     MaybeParseMicrosoftDeclSpecs(attrs);
3866   }
3867 
3868   // C++11 [temp.explicit]p12:
3869   //   The usual access controls do not apply to names used to specify
3870   //   explicit instantiations.
3871   // We extend this to also cover explicit specializations.  Note that
3872   // we don't suppress if this turns out to be an elaborated type
3873   // specifier.
3874   bool shouldDelayDiagsInTag =
3875     (TemplateInfo.Kind == ParsedTemplateInfo::ExplicitInstantiation ||
3876      TemplateInfo.Kind == ParsedTemplateInfo::ExplicitSpecialization);
3877   SuppressAccessChecks diagsFromTag(*this, shouldDelayDiagsInTag);
3878 
3879   // Enum definitions should not be parsed in a trailing-return-type.
3880   bool AllowDeclaration = DSC != DSC_trailing;
3881 
3882   bool AllowFixedUnderlyingType = AllowDeclaration &&
3883     (getLangOpts().CPlusPlus11 || getLangOpts().MicrosoftExt ||
3884      getLangOpts().ObjC2);
3885 
3886   CXXScopeSpec &SS = DS.getTypeSpecScope();
3887   if (getLangOpts().CPlusPlus) {
3888     // "enum foo : bar;" is not a potential typo for "enum foo::bar;"
3889     // if a fixed underlying type is allowed.
3890     ColonProtectionRAIIObject X(*this, AllowFixedUnderlyingType);
3891 
3892     CXXScopeSpec Spec;
3893     if (ParseOptionalCXXScopeSpecifier(Spec, nullptr,
3894                                        /*EnteringContext=*/true))
3895       return;
3896 
3897     if (Spec.isSet() && Tok.isNot(tok::identifier)) {
3898       Diag(Tok, diag::err_expected) << tok::identifier;
3899       if (Tok.isNot(tok::l_brace)) {
3900         // Has no name and is not a definition.
3901         // Skip the rest of this declarator, up until the comma or semicolon.
3902         SkipUntil(tok::comma, StopAtSemi);
3903         return;
3904       }
3905     }
3906 
3907     SS = Spec;
3908   }
3909 
3910   // Must have either 'enum name' or 'enum {...}'.
3911   if (Tok.isNot(tok::identifier) && Tok.isNot(tok::l_brace) &&
3912       !(AllowFixedUnderlyingType && Tok.is(tok::colon))) {
3913     Diag(Tok, diag::err_expected_either) << tok::identifier << tok::l_brace;
3914 
3915     // Skip the rest of this declarator, up until the comma or semicolon.
3916     SkipUntil(tok::comma, StopAtSemi);
3917     return;
3918   }
3919 
3920   // If an identifier is present, consume and remember it.
3921   IdentifierInfo *Name = nullptr;
3922   SourceLocation NameLoc;
3923   if (Tok.is(tok::identifier)) {
3924     Name = Tok.getIdentifierInfo();
3925     NameLoc = ConsumeToken();
3926   }
3927 
3928   if (!Name && ScopedEnumKWLoc.isValid()) {
3929     // C++0x 7.2p2: The optional identifier shall not be omitted in the
3930     // declaration of a scoped enumeration.
3931     Diag(Tok, diag::err_scoped_enum_missing_identifier);
3932     ScopedEnumKWLoc = SourceLocation();
3933     IsScopedUsingClassTag = false;
3934   }
3935 
3936   // Okay, end the suppression area.  We'll decide whether to emit the
3937   // diagnostics in a second.
3938   if (shouldDelayDiagsInTag)
3939     diagsFromTag.done();
3940 
3941   TypeResult BaseType;
3942 
3943   // Parse the fixed underlying type.
3944   bool CanBeBitfield = getCurScope()->getFlags() & Scope::ClassScope;
3945   if (AllowFixedUnderlyingType && Tok.is(tok::colon)) {
3946     bool PossibleBitfield = false;
3947     if (CanBeBitfield) {
3948       // If we're in class scope, this can either be an enum declaration with
3949       // an underlying type, or a declaration of a bitfield member. We try to
3950       // use a simple disambiguation scheme first to catch the common cases
3951       // (integer literal, sizeof); if it's still ambiguous, we then consider
3952       // anything that's a simple-type-specifier followed by '(' as an
3953       // expression. This suffices because function types are not valid
3954       // underlying types anyway.
3955       EnterExpressionEvaluationContext Unevaluated(Actions,
3956                                                    Sema::ConstantEvaluated);
3957       TPResult TPR = isExpressionOrTypeSpecifierSimple(NextToken().getKind());
3958       // If the next token starts an expression, we know we're parsing a
3959       // bit-field. This is the common case.
3960       if (TPR == TPResult::True)
3961         PossibleBitfield = true;
3962       // If the next token starts a type-specifier-seq, it may be either a
3963       // a fixed underlying type or the start of a function-style cast in C++;
3964       // lookahead one more token to see if it's obvious that we have a
3965       // fixed underlying type.
3966       else if (TPR == TPResult::False &&
3967                GetLookAheadToken(2).getKind() == tok::semi) {
3968         // Consume the ':'.
3969         ConsumeToken();
3970       } else {
3971         // We have the start of a type-specifier-seq, so we have to perform
3972         // tentative parsing to determine whether we have an expression or a
3973         // type.
3974         TentativeParsingAction TPA(*this);
3975 
3976         // Consume the ':'.
3977         ConsumeToken();
3978 
3979         // If we see a type specifier followed by an open-brace, we have an
3980         // ambiguity between an underlying type and a C++11 braced
3981         // function-style cast. Resolve this by always treating it as an
3982         // underlying type.
3983         // FIXME: The standard is not entirely clear on how to disambiguate in
3984         // this case.
3985         if ((getLangOpts().CPlusPlus &&
3986              isCXXDeclarationSpecifier(TPResult::True) != TPResult::True) ||
3987             (!getLangOpts().CPlusPlus && !isDeclarationSpecifier(true))) {
3988           // We'll parse this as a bitfield later.
3989           PossibleBitfield = true;
3990           TPA.Revert();
3991         } else {
3992           // We have a type-specifier-seq.
3993           TPA.Commit();
3994         }
3995       }
3996     } else {
3997       // Consume the ':'.
3998       ConsumeToken();
3999     }
4000 
4001     if (!PossibleBitfield) {
4002       SourceRange Range;
4003       BaseType = ParseTypeName(&Range);
4004 
4005       if (getLangOpts().CPlusPlus11) {
4006         Diag(StartLoc, diag::warn_cxx98_compat_enum_fixed_underlying_type);
4007       } else if (!getLangOpts().ObjC2) {
4008         if (getLangOpts().CPlusPlus)
4009           Diag(StartLoc, diag::ext_cxx11_enum_fixed_underlying_type) << Range;
4010         else
4011           Diag(StartLoc, diag::ext_c_enum_fixed_underlying_type) << Range;
4012       }
4013     }
4014   }
4015 
4016   // There are four options here.  If we have 'friend enum foo;' then this is a
4017   // friend declaration, and cannot have an accompanying definition. If we have
4018   // 'enum foo;', then this is a forward declaration.  If we have
4019   // 'enum foo {...' then this is a definition. Otherwise we have something
4020   // like 'enum foo xyz', a reference.
4021   //
4022   // This is needed to handle stuff like this right (C99 6.7.2.3p11):
4023   // enum foo {..};  void bar() { enum foo; }    <- new foo in bar.
4024   // enum foo {..};  void bar() { enum foo x; }  <- use of old foo.
4025   //
4026   Sema::TagUseKind TUK;
4027   if (!AllowDeclaration) {
4028     TUK = Sema::TUK_Reference;
4029   } else if (Tok.is(tok::l_brace)) {
4030     if (DS.isFriendSpecified()) {
4031       Diag(Tok.getLocation(), diag::err_friend_decl_defines_type)
4032         << SourceRange(DS.getFriendSpecLoc());
4033       ConsumeBrace();
4034       SkipUntil(tok::r_brace, StopAtSemi);
4035       TUK = Sema::TUK_Friend;
4036     } else {
4037       TUK = Sema::TUK_Definition;
4038     }
4039   } else if (!isTypeSpecifier(DSC) &&
4040              (Tok.is(tok::semi) ||
4041               (Tok.isAtStartOfLine() &&
4042                !isValidAfterTypeSpecifier(CanBeBitfield)))) {
4043     TUK = DS.isFriendSpecified() ? Sema::TUK_Friend : Sema::TUK_Declaration;
4044     if (Tok.isNot(tok::semi)) {
4045       // A semicolon was missing after this declaration. Diagnose and recover.
4046       ExpectAndConsume(tok::semi, diag::err_expected_after, "enum");
4047       PP.EnterToken(Tok);
4048       Tok.setKind(tok::semi);
4049     }
4050   } else {
4051     TUK = Sema::TUK_Reference;
4052   }
4053 
4054   // If this is an elaborated type specifier, and we delayed
4055   // diagnostics before, just merge them into the current pool.
4056   if (TUK == Sema::TUK_Reference && shouldDelayDiagsInTag) {
4057     diagsFromTag.redelay();
4058   }
4059 
4060   MultiTemplateParamsArg TParams;
4061   if (TemplateInfo.Kind != ParsedTemplateInfo::NonTemplate &&
4062       TUK != Sema::TUK_Reference) {
4063     if (!getLangOpts().CPlusPlus11 || !SS.isSet()) {
4064       // Skip the rest of this declarator, up until the comma or semicolon.
4065       Diag(Tok, diag::err_enum_template);
4066       SkipUntil(tok::comma, StopAtSemi);
4067       return;
4068     }
4069 
4070     if (TemplateInfo.Kind == ParsedTemplateInfo::ExplicitInstantiation) {
4071       // Enumerations can't be explicitly instantiated.
4072       DS.SetTypeSpecError();
4073       Diag(StartLoc, diag::err_explicit_instantiation_enum);
4074       return;
4075     }
4076 
4077     assert(TemplateInfo.TemplateParams && "no template parameters");
4078     TParams = MultiTemplateParamsArg(TemplateInfo.TemplateParams->data(),
4079                                      TemplateInfo.TemplateParams->size());
4080   }
4081 
4082   if (TUK == Sema::TUK_Reference)
4083     ProhibitAttributes(attrs);
4084 
4085   if (!Name && TUK != Sema::TUK_Definition) {
4086     Diag(Tok, diag::err_enumerator_unnamed_no_def);
4087 
4088     // Skip the rest of this declarator, up until the comma or semicolon.
4089     SkipUntil(tok::comma, StopAtSemi);
4090     return;
4091   }
4092 
4093   stripTypeAttributesOffDeclSpec(attrs, DS, TUK);
4094 
4095   Sema::SkipBodyInfo SkipBody;
4096   if (!Name && TUK == Sema::TUK_Definition && Tok.is(tok::l_brace) &&
4097       NextToken().is(tok::identifier))
4098     SkipBody = Actions.shouldSkipAnonEnumBody(getCurScope(),
4099                                               NextToken().getIdentifierInfo(),
4100                                               NextToken().getLocation());
4101 
4102   bool Owned = false;
4103   bool IsDependent = false;
4104   const char *PrevSpec = nullptr;
4105   unsigned DiagID;
4106   Decl *TagDecl = Actions.ActOnTag(getCurScope(), DeclSpec::TST_enum, TUK,
4107                                    StartLoc, SS, Name, NameLoc, attrs.getList(),
4108                                    AS, DS.getModulePrivateSpecLoc(), TParams,
4109                                    Owned, IsDependent, ScopedEnumKWLoc,
4110                                    IsScopedUsingClassTag, BaseType,
4111                                    DSC == DSC_type_specifier, &SkipBody);
4112 
4113   if (SkipBody.ShouldSkip) {
4114     assert(TUK == Sema::TUK_Definition && "can only skip a definition");
4115 
4116     BalancedDelimiterTracker T(*this, tok::l_brace);
4117     T.consumeOpen();
4118     T.skipToEnd();
4119 
4120     if (DS.SetTypeSpecType(DeclSpec::TST_enum, StartLoc,
4121                            NameLoc.isValid() ? NameLoc : StartLoc,
4122                            PrevSpec, DiagID, TagDecl, Owned,
4123                            Actions.getASTContext().getPrintingPolicy()))
4124       Diag(StartLoc, DiagID) << PrevSpec;
4125     return;
4126   }
4127 
4128   if (IsDependent) {
4129     // This enum has a dependent nested-name-specifier. Handle it as a
4130     // dependent tag.
4131     if (!Name) {
4132       DS.SetTypeSpecError();
4133       Diag(Tok, diag::err_expected_type_name_after_typename);
4134       return;
4135     }
4136 
4137     TypeResult Type = Actions.ActOnDependentTag(
4138         getCurScope(), DeclSpec::TST_enum, TUK, SS, Name, StartLoc, NameLoc);
4139     if (Type.isInvalid()) {
4140       DS.SetTypeSpecError();
4141       return;
4142     }
4143 
4144     if (DS.SetTypeSpecType(DeclSpec::TST_typename, StartLoc,
4145                            NameLoc.isValid() ? NameLoc : StartLoc,
4146                            PrevSpec, DiagID, Type.get(),
4147                            Actions.getASTContext().getPrintingPolicy()))
4148       Diag(StartLoc, DiagID) << PrevSpec;
4149 
4150     return;
4151   }
4152 
4153   if (!TagDecl) {
4154     // The action failed to produce an enumeration tag. If this is a
4155     // definition, consume the entire definition.
4156     if (Tok.is(tok::l_brace) && TUK != Sema::TUK_Reference) {
4157       ConsumeBrace();
4158       SkipUntil(tok::r_brace, StopAtSemi);
4159     }
4160 
4161     DS.SetTypeSpecError();
4162     return;
4163   }
4164 
4165   if (Tok.is(tok::l_brace) && TUK != Sema::TUK_Reference)
4166     ParseEnumBody(StartLoc, TagDecl);
4167 
4168   if (DS.SetTypeSpecType(DeclSpec::TST_enum, StartLoc,
4169                          NameLoc.isValid() ? NameLoc : StartLoc,
4170                          PrevSpec, DiagID, TagDecl, Owned,
4171                          Actions.getASTContext().getPrintingPolicy()))
4172     Diag(StartLoc, DiagID) << PrevSpec;
4173 }
4174 
4175 /// ParseEnumBody - Parse a {} enclosed enumerator-list.
4176 ///       enumerator-list:
4177 ///         enumerator
4178 ///         enumerator-list ',' enumerator
4179 ///       enumerator:
4180 ///         enumeration-constant attributes[opt]
4181 ///         enumeration-constant attributes[opt] '=' constant-expression
4182 ///       enumeration-constant:
4183 ///         identifier
4184 ///
4185 void Parser::ParseEnumBody(SourceLocation StartLoc, Decl *EnumDecl) {
4186   // Enter the scope of the enum body and start the definition.
4187   ParseScope EnumScope(this, Scope::DeclScope | Scope::EnumScope);
4188   Actions.ActOnTagStartDefinition(getCurScope(), EnumDecl);
4189 
4190   BalancedDelimiterTracker T(*this, tok::l_brace);
4191   T.consumeOpen();
4192 
4193   // C does not allow an empty enumerator-list, C++ does [dcl.enum].
4194   if (Tok.is(tok::r_brace) && !getLangOpts().CPlusPlus)
4195     Diag(Tok, diag::err_empty_enum);
4196 
4197   SmallVector<Decl *, 32> EnumConstantDecls;
4198   SmallVector<SuppressAccessChecks, 32> EnumAvailabilityDiags;
4199 
4200   Decl *LastEnumConstDecl = nullptr;
4201 
4202   // Parse the enumerator-list.
4203   while (Tok.isNot(tok::r_brace)) {
4204     // Parse enumerator. If failed, try skipping till the start of the next
4205     // enumerator definition.
4206     if (Tok.isNot(tok::identifier)) {
4207       Diag(Tok.getLocation(), diag::err_expected) << tok::identifier;
4208       if (SkipUntil(tok::comma, tok::r_brace, StopBeforeMatch) &&
4209           TryConsumeToken(tok::comma))
4210         continue;
4211       break;
4212     }
4213     IdentifierInfo *Ident = Tok.getIdentifierInfo();
4214     SourceLocation IdentLoc = ConsumeToken();
4215 
4216     // If attributes exist after the enumerator, parse them.
4217     ParsedAttributesWithRange attrs(AttrFactory);
4218     MaybeParseGNUAttributes(attrs);
4219     ProhibitAttributes(attrs); // GNU-style attributes are prohibited.
4220     if (getLangOpts().CPlusPlus11 && isCXX11AttributeSpecifier()) {
4221       if (!getLangOpts().CPlusPlus1z)
4222         Diag(Tok.getLocation(), diag::warn_cxx14_compat_attribute)
4223             << 1 /*enumerator*/;
4224       ParseCXX11Attributes(attrs);
4225     }
4226 
4227     SourceLocation EqualLoc;
4228     ExprResult AssignedVal;
4229     EnumAvailabilityDiags.emplace_back(*this);
4230 
4231     if (TryConsumeToken(tok::equal, EqualLoc)) {
4232       AssignedVal = ParseConstantExpression();
4233       if (AssignedVal.isInvalid())
4234         SkipUntil(tok::comma, tok::r_brace, StopBeforeMatch);
4235     }
4236 
4237     // Install the enumerator constant into EnumDecl.
4238     Decl *EnumConstDecl = Actions.ActOnEnumConstant(getCurScope(), EnumDecl,
4239                                                     LastEnumConstDecl,
4240                                                     IdentLoc, Ident,
4241                                                     attrs.getList(), EqualLoc,
4242                                                     AssignedVal.get());
4243     EnumAvailabilityDiags.back().done();
4244 
4245     EnumConstantDecls.push_back(EnumConstDecl);
4246     LastEnumConstDecl = EnumConstDecl;
4247 
4248     if (Tok.is(tok::identifier)) {
4249       // We're missing a comma between enumerators.
4250       SourceLocation Loc = getEndOfPreviousToken();
4251       Diag(Loc, diag::err_enumerator_list_missing_comma)
4252         << FixItHint::CreateInsertion(Loc, ", ");
4253       continue;
4254     }
4255 
4256     // Emumerator definition must be finished, only comma or r_brace are
4257     // allowed here.
4258     SourceLocation CommaLoc;
4259     if (Tok.isNot(tok::r_brace) && !TryConsumeToken(tok::comma, CommaLoc)) {
4260       if (EqualLoc.isValid())
4261         Diag(Tok.getLocation(), diag::err_expected_either) << tok::r_brace
4262                                                            << tok::comma;
4263       else
4264         Diag(Tok.getLocation(), diag::err_expected_end_of_enumerator);
4265       if (SkipUntil(tok::comma, tok::r_brace, StopBeforeMatch)) {
4266         if (TryConsumeToken(tok::comma, CommaLoc))
4267           continue;
4268       } else {
4269         break;
4270       }
4271     }
4272 
4273     // If comma is followed by r_brace, emit appropriate warning.
4274     if (Tok.is(tok::r_brace) && CommaLoc.isValid()) {
4275       if (!getLangOpts().C99 && !getLangOpts().CPlusPlus11)
4276         Diag(CommaLoc, getLangOpts().CPlusPlus ?
4277                diag::ext_enumerator_list_comma_cxx :
4278                diag::ext_enumerator_list_comma_c)
4279           << FixItHint::CreateRemoval(CommaLoc);
4280       else if (getLangOpts().CPlusPlus11)
4281         Diag(CommaLoc, diag::warn_cxx98_compat_enumerator_list_comma)
4282           << FixItHint::CreateRemoval(CommaLoc);
4283       break;
4284     }
4285   }
4286 
4287   // Eat the }.
4288   T.consumeClose();
4289 
4290   // If attributes exist after the identifier list, parse them.
4291   ParsedAttributes attrs(AttrFactory);
4292   MaybeParseGNUAttributes(attrs);
4293 
4294   Actions.ActOnEnumBody(StartLoc, T.getRange(),
4295                         EnumDecl, EnumConstantDecls,
4296                         getCurScope(),
4297                         attrs.getList());
4298 
4299   // Now handle enum constant availability diagnostics.
4300   assert(EnumConstantDecls.size() == EnumAvailabilityDiags.size());
4301   for (size_t i = 0, e = EnumConstantDecls.size(); i != e; ++i) {
4302     ParsingDeclRAIIObject PD(*this, ParsingDeclRAIIObject::NoParent);
4303     EnumAvailabilityDiags[i].redelay();
4304     PD.complete(EnumConstantDecls[i]);
4305   }
4306 
4307   EnumScope.Exit();
4308   Actions.ActOnTagFinishDefinition(getCurScope(), EnumDecl, T.getRange());
4309 
4310   // The next token must be valid after an enum definition. If not, a ';'
4311   // was probably forgotten.
4312   bool CanBeBitfield = getCurScope()->getFlags() & Scope::ClassScope;
4313   if (!isValidAfterTypeSpecifier(CanBeBitfield)) {
4314     ExpectAndConsume(tok::semi, diag::err_expected_after, "enum");
4315     // Push this token back into the preprocessor and change our current token
4316     // to ';' so that the rest of the code recovers as though there were an
4317     // ';' after the definition.
4318     PP.EnterToken(Tok);
4319     Tok.setKind(tok::semi);
4320   }
4321 }
4322 
4323 /// isKnownToBeTypeSpecifier - Return true if we know that the specified token
4324 /// is definitely a type-specifier.  Return false if it isn't part of a type
4325 /// specifier or if we're not sure.
4326 bool Parser::isKnownToBeTypeSpecifier(const Token &Tok) const {
4327   switch (Tok.getKind()) {
4328   default: return false;
4329     // type-specifiers
4330   case tok::kw_short:
4331   case tok::kw_long:
4332   case tok::kw___int64:
4333   case tok::kw___int128:
4334   case tok::kw_signed:
4335   case tok::kw_unsigned:
4336   case tok::kw__Complex:
4337   case tok::kw__Imaginary:
4338   case tok::kw_void:
4339   case tok::kw_char:
4340   case tok::kw_wchar_t:
4341   case tok::kw_char16_t:
4342   case tok::kw_char32_t:
4343   case tok::kw_int:
4344   case tok::kw_half:
4345   case tok::kw_float:
4346   case tok::kw_double:
4347   case tok::kw___float128:
4348   case tok::kw_bool:
4349   case tok::kw__Bool:
4350   case tok::kw__Decimal32:
4351   case tok::kw__Decimal64:
4352   case tok::kw__Decimal128:
4353   case tok::kw___vector:
4354 #define GENERIC_IMAGE_TYPE(ImgType, Id) case tok::kw_##ImgType##_t:
4355 #include "clang/Basic/OpenCLImageTypes.def"
4356 
4357     // struct-or-union-specifier (C99) or class-specifier (C++)
4358   case tok::kw_class:
4359   case tok::kw_struct:
4360   case tok::kw___interface:
4361   case tok::kw_union:
4362     // enum-specifier
4363   case tok::kw_enum:
4364 
4365     // typedef-name
4366   case tok::annot_typename:
4367     return true;
4368   }
4369 }
4370 
4371 /// isTypeSpecifierQualifier - Return true if the current token could be the
4372 /// start of a specifier-qualifier-list.
4373 bool Parser::isTypeSpecifierQualifier() {
4374   switch (Tok.getKind()) {
4375   default: return false;
4376 
4377   case tok::identifier:   // foo::bar
4378     if (TryAltiVecVectorToken())
4379       return true;
4380     // Fall through.
4381   case tok::kw_typename:  // typename T::type
4382     // Annotate typenames and C++ scope specifiers.  If we get one, just
4383     // recurse to handle whatever we get.
4384     if (TryAnnotateTypeOrScopeToken())
4385       return true;
4386     if (Tok.is(tok::identifier))
4387       return false;
4388     return isTypeSpecifierQualifier();
4389 
4390   case tok::coloncolon:   // ::foo::bar
4391     if (NextToken().is(tok::kw_new) ||    // ::new
4392         NextToken().is(tok::kw_delete))   // ::delete
4393       return false;
4394 
4395     if (TryAnnotateTypeOrScopeToken())
4396       return true;
4397     return isTypeSpecifierQualifier();
4398 
4399     // GNU attributes support.
4400   case tok::kw___attribute:
4401     // GNU typeof support.
4402   case tok::kw_typeof:
4403 
4404     // type-specifiers
4405   case tok::kw_short:
4406   case tok::kw_long:
4407   case tok::kw___int64:
4408   case tok::kw___int128:
4409   case tok::kw_signed:
4410   case tok::kw_unsigned:
4411   case tok::kw__Complex:
4412   case tok::kw__Imaginary:
4413   case tok::kw_void:
4414   case tok::kw_char:
4415   case tok::kw_wchar_t:
4416   case tok::kw_char16_t:
4417   case tok::kw_char32_t:
4418   case tok::kw_int:
4419   case tok::kw_half:
4420   case tok::kw_float:
4421   case tok::kw_double:
4422   case tok::kw___float128:
4423   case tok::kw_bool:
4424   case tok::kw__Bool:
4425   case tok::kw__Decimal32:
4426   case tok::kw__Decimal64:
4427   case tok::kw__Decimal128:
4428   case tok::kw___vector:
4429 #define GENERIC_IMAGE_TYPE(ImgType, Id) case tok::kw_##ImgType##_t:
4430 #include "clang/Basic/OpenCLImageTypes.def"
4431 
4432     // struct-or-union-specifier (C99) or class-specifier (C++)
4433   case tok::kw_class:
4434   case tok::kw_struct:
4435   case tok::kw___interface:
4436   case tok::kw_union:
4437     // enum-specifier
4438   case tok::kw_enum:
4439 
4440     // type-qualifier
4441   case tok::kw_const:
4442   case tok::kw_volatile:
4443   case tok::kw_restrict:
4444 
4445     // Debugger support.
4446   case tok::kw___unknown_anytype:
4447 
4448     // typedef-name
4449   case tok::annot_typename:
4450     return true;
4451 
4452     // GNU ObjC bizarre protocol extension: <proto1,proto2> with implicit 'id'.
4453   case tok::less:
4454     return getLangOpts().ObjC1;
4455 
4456   case tok::kw___cdecl:
4457   case tok::kw___stdcall:
4458   case tok::kw___fastcall:
4459   case tok::kw___thiscall:
4460   case tok::kw___regcall:
4461   case tok::kw___vectorcall:
4462   case tok::kw___w64:
4463   case tok::kw___ptr64:
4464   case tok::kw___ptr32:
4465   case tok::kw___pascal:
4466   case tok::kw___unaligned:
4467 
4468   case tok::kw__Nonnull:
4469   case tok::kw__Nullable:
4470   case tok::kw__Null_unspecified:
4471 
4472   case tok::kw___kindof:
4473 
4474   case tok::kw___private:
4475   case tok::kw___local:
4476   case tok::kw___global:
4477   case tok::kw___constant:
4478   case tok::kw___generic:
4479   case tok::kw___read_only:
4480   case tok::kw___read_write:
4481   case tok::kw___write_only:
4482 
4483     return true;
4484 
4485   // C11 _Atomic
4486   case tok::kw__Atomic:
4487     return true;
4488   }
4489 }
4490 
4491 /// isDeclarationSpecifier() - Return true if the current token is part of a
4492 /// declaration specifier.
4493 ///
4494 /// \param DisambiguatingWithExpression True to indicate that the purpose of
4495 /// this check is to disambiguate between an expression and a declaration.
4496 bool Parser::isDeclarationSpecifier(bool DisambiguatingWithExpression) {
4497   switch (Tok.getKind()) {
4498   default: return false;
4499 
4500   case tok::kw_pipe:
4501     return getLangOpts().OpenCL && (getLangOpts().OpenCLVersion >= 200);
4502 
4503   case tok::identifier:   // foo::bar
4504     // Unfortunate hack to support "Class.factoryMethod" notation.
4505     if (getLangOpts().ObjC1 && NextToken().is(tok::period))
4506       return false;
4507     if (TryAltiVecVectorToken())
4508       return true;
4509     // Fall through.
4510   case tok::kw_decltype: // decltype(T())::type
4511   case tok::kw_typename: // typename T::type
4512     // Annotate typenames and C++ scope specifiers.  If we get one, just
4513     // recurse to handle whatever we get.
4514     if (TryAnnotateTypeOrScopeToken())
4515       return true;
4516     if (Tok.is(tok::identifier))
4517       return false;
4518 
4519     // If we're in Objective-C and we have an Objective-C class type followed
4520     // by an identifier and then either ':' or ']', in a place where an
4521     // expression is permitted, then this is probably a class message send
4522     // missing the initial '['. In this case, we won't consider this to be
4523     // the start of a declaration.
4524     if (DisambiguatingWithExpression &&
4525         isStartOfObjCClassMessageMissingOpenBracket())
4526       return false;
4527 
4528     return isDeclarationSpecifier();
4529 
4530   case tok::coloncolon:   // ::foo::bar
4531     if (NextToken().is(tok::kw_new) ||    // ::new
4532         NextToken().is(tok::kw_delete))   // ::delete
4533       return false;
4534 
4535     // Annotate typenames and C++ scope specifiers.  If we get one, just
4536     // recurse to handle whatever we get.
4537     if (TryAnnotateTypeOrScopeToken())
4538       return true;
4539     return isDeclarationSpecifier();
4540 
4541     // storage-class-specifier
4542   case tok::kw_typedef:
4543   case tok::kw_extern:
4544   case tok::kw___private_extern__:
4545   case tok::kw_static:
4546   case tok::kw_auto:
4547   case tok::kw___auto_type:
4548   case tok::kw_register:
4549   case tok::kw___thread:
4550   case tok::kw_thread_local:
4551   case tok::kw__Thread_local:
4552 
4553     // Modules
4554   case tok::kw___module_private__:
4555 
4556     // Debugger support
4557   case tok::kw___unknown_anytype:
4558 
4559     // type-specifiers
4560   case tok::kw_short:
4561   case tok::kw_long:
4562   case tok::kw___int64:
4563   case tok::kw___int128:
4564   case tok::kw_signed:
4565   case tok::kw_unsigned:
4566   case tok::kw__Complex:
4567   case tok::kw__Imaginary:
4568   case tok::kw_void:
4569   case tok::kw_char:
4570   case tok::kw_wchar_t:
4571   case tok::kw_char16_t:
4572   case tok::kw_char32_t:
4573 
4574   case tok::kw_int:
4575   case tok::kw_half:
4576   case tok::kw_float:
4577   case tok::kw_double:
4578   case tok::kw___float128:
4579   case tok::kw_bool:
4580   case tok::kw__Bool:
4581   case tok::kw__Decimal32:
4582   case tok::kw__Decimal64:
4583   case tok::kw__Decimal128:
4584   case tok::kw___vector:
4585 
4586     // struct-or-union-specifier (C99) or class-specifier (C++)
4587   case tok::kw_class:
4588   case tok::kw_struct:
4589   case tok::kw_union:
4590   case tok::kw___interface:
4591     // enum-specifier
4592   case tok::kw_enum:
4593 
4594     // type-qualifier
4595   case tok::kw_const:
4596   case tok::kw_volatile:
4597   case tok::kw_restrict:
4598 
4599     // function-specifier
4600   case tok::kw_inline:
4601   case tok::kw_virtual:
4602   case tok::kw_explicit:
4603   case tok::kw__Noreturn:
4604 
4605     // alignment-specifier
4606   case tok::kw__Alignas:
4607 
4608     // friend keyword.
4609   case tok::kw_friend:
4610 
4611     // static_assert-declaration
4612   case tok::kw__Static_assert:
4613 
4614     // GNU typeof support.
4615   case tok::kw_typeof:
4616 
4617     // GNU attributes.
4618   case tok::kw___attribute:
4619 
4620     // C++11 decltype and constexpr.
4621   case tok::annot_decltype:
4622   case tok::kw_constexpr:
4623 
4624     // C++ Concepts TS - concept
4625   case tok::kw_concept:
4626 
4627     // C11 _Atomic
4628   case tok::kw__Atomic:
4629     return true;
4630 
4631     // GNU ObjC bizarre protocol extension: <proto1,proto2> with implicit 'id'.
4632   case tok::less:
4633     return getLangOpts().ObjC1;
4634 
4635     // typedef-name
4636   case tok::annot_typename:
4637     return !DisambiguatingWithExpression ||
4638            !isStartOfObjCClassMessageMissingOpenBracket();
4639 
4640   case tok::kw___declspec:
4641   case tok::kw___cdecl:
4642   case tok::kw___stdcall:
4643   case tok::kw___fastcall:
4644   case tok::kw___thiscall:
4645   case tok::kw___regcall:
4646   case tok::kw___vectorcall:
4647   case tok::kw___w64:
4648   case tok::kw___sptr:
4649   case tok::kw___uptr:
4650   case tok::kw___ptr64:
4651   case tok::kw___ptr32:
4652   case tok::kw___forceinline:
4653   case tok::kw___pascal:
4654   case tok::kw___unaligned:
4655 
4656   case tok::kw__Nonnull:
4657   case tok::kw__Nullable:
4658   case tok::kw__Null_unspecified:
4659 
4660   case tok::kw___kindof:
4661 
4662   case tok::kw___private:
4663   case tok::kw___local:
4664   case tok::kw___global:
4665   case tok::kw___constant:
4666   case tok::kw___generic:
4667   case tok::kw___read_only:
4668   case tok::kw___read_write:
4669   case tok::kw___write_only:
4670 #define GENERIC_IMAGE_TYPE(ImgType, Id) case tok::kw_##ImgType##_t:
4671 #include "clang/Basic/OpenCLImageTypes.def"
4672 
4673     return true;
4674   }
4675 }
4676 
4677 bool Parser::isConstructorDeclarator(bool IsUnqualified) {
4678   TentativeParsingAction TPA(*this);
4679 
4680   // Parse the C++ scope specifier.
4681   CXXScopeSpec SS;
4682   if (ParseOptionalCXXScopeSpecifier(SS, nullptr,
4683                                      /*EnteringContext=*/true)) {
4684     TPA.Revert();
4685     return false;
4686   }
4687 
4688   // Parse the constructor name.
4689   if (Tok.isOneOf(tok::identifier, tok::annot_template_id)) {
4690     // We already know that we have a constructor name; just consume
4691     // the token.
4692     ConsumeToken();
4693   } else {
4694     TPA.Revert();
4695     return false;
4696   }
4697 
4698   // Current class name must be followed by a left parenthesis.
4699   if (Tok.isNot(tok::l_paren)) {
4700     TPA.Revert();
4701     return false;
4702   }
4703   ConsumeParen();
4704 
4705   // A right parenthesis, or ellipsis followed by a right parenthesis signals
4706   // that we have a constructor.
4707   if (Tok.is(tok::r_paren) ||
4708       (Tok.is(tok::ellipsis) && NextToken().is(tok::r_paren))) {
4709     TPA.Revert();
4710     return true;
4711   }
4712 
4713   // A C++11 attribute here signals that we have a constructor, and is an
4714   // attribute on the first constructor parameter.
4715   if (getLangOpts().CPlusPlus11 &&
4716       isCXX11AttributeSpecifier(/*Disambiguate*/ false,
4717                                 /*OuterMightBeMessageSend*/ true)) {
4718     TPA.Revert();
4719     return true;
4720   }
4721 
4722   // If we need to, enter the specified scope.
4723   DeclaratorScopeObj DeclScopeObj(*this, SS);
4724   if (SS.isSet() && Actions.ShouldEnterDeclaratorScope(getCurScope(), SS))
4725     DeclScopeObj.EnterDeclaratorScope();
4726 
4727   // Optionally skip Microsoft attributes.
4728   ParsedAttributes Attrs(AttrFactory);
4729   MaybeParseMicrosoftAttributes(Attrs);
4730 
4731   // Check whether the next token(s) are part of a declaration
4732   // specifier, in which case we have the start of a parameter and,
4733   // therefore, we know that this is a constructor.
4734   bool IsConstructor = false;
4735   if (isDeclarationSpecifier())
4736     IsConstructor = true;
4737   else if (Tok.is(tok::identifier) ||
4738            (Tok.is(tok::annot_cxxscope) && NextToken().is(tok::identifier))) {
4739     // We've seen "C ( X" or "C ( X::Y", but "X" / "X::Y" is not a type.
4740     // This might be a parenthesized member name, but is more likely to
4741     // be a constructor declaration with an invalid argument type. Keep
4742     // looking.
4743     if (Tok.is(tok::annot_cxxscope))
4744       ConsumeToken();
4745     ConsumeToken();
4746 
4747     // If this is not a constructor, we must be parsing a declarator,
4748     // which must have one of the following syntactic forms (see the
4749     // grammar extract at the start of ParseDirectDeclarator):
4750     switch (Tok.getKind()) {
4751     case tok::l_paren:
4752       // C(X   (   int));
4753     case tok::l_square:
4754       // C(X   [   5]);
4755       // C(X   [   [attribute]]);
4756     case tok::coloncolon:
4757       // C(X   ::   Y);
4758       // C(X   ::   *p);
4759       // Assume this isn't a constructor, rather than assuming it's a
4760       // constructor with an unnamed parameter of an ill-formed type.
4761       break;
4762 
4763     case tok::r_paren:
4764       // C(X   )
4765       if (NextToken().is(tok::colon) || NextToken().is(tok::kw_try)) {
4766         // Assume these were meant to be constructors:
4767         //   C(X)   :    (the name of a bit-field cannot be parenthesized).
4768         //   C(X)   try  (this is otherwise ill-formed).
4769         IsConstructor = true;
4770       }
4771       if (NextToken().is(tok::semi) || NextToken().is(tok::l_brace)) {
4772         // If we have a constructor name within the class definition,
4773         // assume these were meant to be constructors:
4774         //   C(X)   {
4775         //   C(X)   ;
4776         // ... because otherwise we would be declaring a non-static data
4777         // member that is ill-formed because it's of the same type as its
4778         // surrounding class.
4779         //
4780         // FIXME: We can actually do this whether or not the name is qualified,
4781         // because if it is qualified in this context it must be being used as
4782         // a constructor name. However, we do not implement that rule correctly
4783         // currently, so we're somewhat conservative here.
4784         IsConstructor = IsUnqualified;
4785       }
4786       break;
4787 
4788     default:
4789       IsConstructor = true;
4790       break;
4791     }
4792   }
4793 
4794   TPA.Revert();
4795   return IsConstructor;
4796 }
4797 
4798 /// ParseTypeQualifierListOpt
4799 ///          type-qualifier-list: [C99 6.7.5]
4800 ///            type-qualifier
4801 /// [vendor]   attributes
4802 ///              [ only if AttrReqs & AR_VendorAttributesParsed ]
4803 ///            type-qualifier-list type-qualifier
4804 /// [vendor]   type-qualifier-list attributes
4805 ///              [ only if AttrReqs & AR_VendorAttributesParsed ]
4806 /// [C++0x]    attribute-specifier[opt] is allowed before cv-qualifier-seq
4807 ///              [ only if AttReqs & AR_CXX11AttributesParsed ]
4808 /// Note: vendor can be GNU, MS, etc and can be explicitly controlled via
4809 /// AttrRequirements bitmask values.
4810 void Parser::ParseTypeQualifierListOpt(DeclSpec &DS, unsigned AttrReqs,
4811                                        bool AtomicAllowed,
4812                                        bool IdentifierRequired) {
4813   if (getLangOpts().CPlusPlus11 && (AttrReqs & AR_CXX11AttributesParsed) &&
4814       isCXX11AttributeSpecifier()) {
4815     ParsedAttributesWithRange attrs(AttrFactory);
4816     ParseCXX11Attributes(attrs);
4817     DS.takeAttributesFrom(attrs);
4818   }
4819 
4820   SourceLocation EndLoc;
4821 
4822   while (1) {
4823     bool isInvalid = false;
4824     const char *PrevSpec = nullptr;
4825     unsigned DiagID = 0;
4826     SourceLocation Loc = Tok.getLocation();
4827 
4828     switch (Tok.getKind()) {
4829     case tok::code_completion:
4830       Actions.CodeCompleteTypeQualifiers(DS);
4831       return cutOffParsing();
4832 
4833     case tok::kw_const:
4834       isInvalid = DS.SetTypeQual(DeclSpec::TQ_const   , Loc, PrevSpec, DiagID,
4835                                  getLangOpts());
4836       break;
4837     case tok::kw_volatile:
4838       isInvalid = DS.SetTypeQual(DeclSpec::TQ_volatile, Loc, PrevSpec, DiagID,
4839                                  getLangOpts());
4840       break;
4841     case tok::kw_restrict:
4842       isInvalid = DS.SetTypeQual(DeclSpec::TQ_restrict, Loc, PrevSpec, DiagID,
4843                                  getLangOpts());
4844       break;
4845     case tok::kw__Atomic:
4846       if (!AtomicAllowed)
4847         goto DoneWithTypeQuals;
4848       isInvalid = DS.SetTypeQual(DeclSpec::TQ_atomic, Loc, PrevSpec, DiagID,
4849                                  getLangOpts());
4850       break;
4851 
4852     // OpenCL qualifiers:
4853     case tok::kw___private:
4854     case tok::kw___global:
4855     case tok::kw___local:
4856     case tok::kw___constant:
4857     case tok::kw___generic:
4858     case tok::kw___read_only:
4859     case tok::kw___write_only:
4860     case tok::kw___read_write:
4861       ParseOpenCLQualifiers(DS.getAttributes());
4862       break;
4863 
4864     case tok::kw___unaligned:
4865       isInvalid = DS.SetTypeQual(DeclSpec::TQ_unaligned, Loc, PrevSpec, DiagID,
4866                                  getLangOpts());
4867       break;
4868     case tok::kw___uptr:
4869       // GNU libc headers in C mode use '__uptr' as an identifer which conflicts
4870       // with the MS modifier keyword.
4871       if ((AttrReqs & AR_DeclspecAttributesParsed) && !getLangOpts().CPlusPlus &&
4872           IdentifierRequired && DS.isEmpty() && NextToken().is(tok::semi)) {
4873         if (TryKeywordIdentFallback(false))
4874           continue;
4875       }
4876     case tok::kw___sptr:
4877     case tok::kw___w64:
4878     case tok::kw___ptr64:
4879     case tok::kw___ptr32:
4880     case tok::kw___cdecl:
4881     case tok::kw___stdcall:
4882     case tok::kw___fastcall:
4883     case tok::kw___thiscall:
4884     case tok::kw___regcall:
4885     case tok::kw___vectorcall:
4886       if (AttrReqs & AR_DeclspecAttributesParsed) {
4887         ParseMicrosoftTypeAttributes(DS.getAttributes());
4888         continue;
4889       }
4890       goto DoneWithTypeQuals;
4891     case tok::kw___pascal:
4892       if (AttrReqs & AR_VendorAttributesParsed) {
4893         ParseBorlandTypeAttributes(DS.getAttributes());
4894         continue;
4895       }
4896       goto DoneWithTypeQuals;
4897 
4898     // Nullability type specifiers.
4899     case tok::kw__Nonnull:
4900     case tok::kw__Nullable:
4901     case tok::kw__Null_unspecified:
4902       ParseNullabilityTypeSpecifiers(DS.getAttributes());
4903       continue;
4904 
4905     // Objective-C 'kindof' types.
4906     case tok::kw___kindof:
4907       DS.getAttributes().addNew(Tok.getIdentifierInfo(), Loc, nullptr, Loc,
4908                                 nullptr, 0, AttributeList::AS_Keyword);
4909       (void)ConsumeToken();
4910       continue;
4911 
4912     case tok::kw___attribute:
4913       if (AttrReqs & AR_GNUAttributesParsedAndRejected)
4914         // When GNU attributes are expressly forbidden, diagnose their usage.
4915         Diag(Tok, diag::err_attributes_not_allowed);
4916 
4917       // Parse the attributes even if they are rejected to ensure that error
4918       // recovery is graceful.
4919       if (AttrReqs & AR_GNUAttributesParsed ||
4920           AttrReqs & AR_GNUAttributesParsedAndRejected) {
4921         ParseGNUAttributes(DS.getAttributes());
4922         continue; // do *not* consume the next token!
4923       }
4924       // otherwise, FALL THROUGH!
4925     default:
4926       DoneWithTypeQuals:
4927       // If this is not a type-qualifier token, we're done reading type
4928       // qualifiers.  First verify that DeclSpec's are consistent.
4929       DS.Finish(Actions, Actions.getASTContext().getPrintingPolicy());
4930       if (EndLoc.isValid())
4931         DS.SetRangeEnd(EndLoc);
4932       return;
4933     }
4934 
4935     // If the specifier combination wasn't legal, issue a diagnostic.
4936     if (isInvalid) {
4937       assert(PrevSpec && "Method did not return previous specifier!");
4938       Diag(Tok, DiagID) << PrevSpec;
4939     }
4940     EndLoc = ConsumeToken();
4941   }
4942 }
4943 
4944 /// ParseDeclarator - Parse and verify a newly-initialized declarator.
4945 ///
4946 void Parser::ParseDeclarator(Declarator &D) {
4947   /// This implements the 'declarator' production in the C grammar, then checks
4948   /// for well-formedness and issues diagnostics.
4949   ParseDeclaratorInternal(D, &Parser::ParseDirectDeclarator);
4950 }
4951 
4952 static bool isPtrOperatorToken(tok::TokenKind Kind, const LangOptions &Lang,
4953                                unsigned TheContext) {
4954   if (Kind == tok::star || Kind == tok::caret)
4955     return true;
4956 
4957   if ((Kind == tok::kw_pipe) && Lang.OpenCL && (Lang.OpenCLVersion >= 200))
4958     return true;
4959 
4960   if (!Lang.CPlusPlus)
4961     return false;
4962 
4963   if (Kind == tok::amp)
4964     return true;
4965 
4966   // We parse rvalue refs in C++03, because otherwise the errors are scary.
4967   // But we must not parse them in conversion-type-ids and new-type-ids, since
4968   // those can be legitimately followed by a && operator.
4969   // (The same thing can in theory happen after a trailing-return-type, but
4970   // since those are a C++11 feature, there is no rejects-valid issue there.)
4971   if (Kind == tok::ampamp)
4972     return Lang.CPlusPlus11 || (TheContext != Declarator::ConversionIdContext &&
4973                                 TheContext != Declarator::CXXNewContext);
4974 
4975   return false;
4976 }
4977 
4978 // Indicates whether the given declarator is a pipe declarator.
4979 static bool isPipeDeclerator(const Declarator &D) {
4980   const unsigned NumTypes = D.getNumTypeObjects();
4981 
4982   for (unsigned Idx = 0; Idx != NumTypes; ++Idx)
4983     if (DeclaratorChunk::Pipe == D.getTypeObject(Idx).Kind)
4984       return true;
4985 
4986   return false;
4987 }
4988 
4989 /// ParseDeclaratorInternal - Parse a C or C++ declarator. The direct-declarator
4990 /// is parsed by the function passed to it. Pass null, and the direct-declarator
4991 /// isn't parsed at all, making this function effectively parse the C++
4992 /// ptr-operator production.
4993 ///
4994 /// If the grammar of this construct is extended, matching changes must also be
4995 /// made to TryParseDeclarator and MightBeDeclarator, and possibly to
4996 /// isConstructorDeclarator.
4997 ///
4998 ///       declarator: [C99 6.7.5] [C++ 8p4, dcl.decl]
4999 /// [C]     pointer[opt] direct-declarator
5000 /// [C++]   direct-declarator
5001 /// [C++]   ptr-operator declarator
5002 ///
5003 ///       pointer: [C99 6.7.5]
5004 ///         '*' type-qualifier-list[opt]
5005 ///         '*' type-qualifier-list[opt] pointer
5006 ///
5007 ///       ptr-operator:
5008 ///         '*' cv-qualifier-seq[opt]
5009 ///         '&'
5010 /// [C++0x] '&&'
5011 /// [GNU]   '&' restrict[opt] attributes[opt]
5012 /// [GNU?]  '&&' restrict[opt] attributes[opt]
5013 ///         '::'[opt] nested-name-specifier '*' cv-qualifier-seq[opt]
5014 void Parser::ParseDeclaratorInternal(Declarator &D,
5015                                      DirectDeclParseFunction DirectDeclParser) {
5016   if (Diags.hasAllExtensionsSilenced())
5017     D.setExtension();
5018 
5019   // C++ member pointers start with a '::' or a nested-name.
5020   // Member pointers get special handling, since there's no place for the
5021   // scope spec in the generic path below.
5022   if (getLangOpts().CPlusPlus &&
5023       (Tok.is(tok::coloncolon) || Tok.is(tok::kw_decltype) ||
5024        (Tok.is(tok::identifier) &&
5025         (NextToken().is(tok::coloncolon) || NextToken().is(tok::less))) ||
5026        Tok.is(tok::annot_cxxscope))) {
5027     bool EnteringContext = D.getContext() == Declarator::FileContext ||
5028                            D.getContext() == Declarator::MemberContext;
5029     CXXScopeSpec SS;
5030     ParseOptionalCXXScopeSpecifier(SS, nullptr, EnteringContext);
5031 
5032     if (SS.isNotEmpty()) {
5033       if (Tok.isNot(tok::star)) {
5034         // The scope spec really belongs to the direct-declarator.
5035         if (D.mayHaveIdentifier())
5036           D.getCXXScopeSpec() = SS;
5037         else
5038           AnnotateScopeToken(SS, true);
5039 
5040         if (DirectDeclParser)
5041           (this->*DirectDeclParser)(D);
5042         return;
5043       }
5044 
5045       SourceLocation Loc = ConsumeToken();
5046       D.SetRangeEnd(Loc);
5047       DeclSpec DS(AttrFactory);
5048       ParseTypeQualifierListOpt(DS);
5049       D.ExtendWithDeclSpec(DS);
5050 
5051       // Recurse to parse whatever is left.
5052       ParseDeclaratorInternal(D, DirectDeclParser);
5053 
5054       // Sema will have to catch (syntactically invalid) pointers into global
5055       // scope. It has to catch pointers into namespace scope anyway.
5056       D.AddTypeInfo(DeclaratorChunk::getMemberPointer(SS,DS.getTypeQualifiers(),
5057                                                       DS.getLocEnd()),
5058                     DS.getAttributes(),
5059                     /* Don't replace range end. */SourceLocation());
5060       return;
5061     }
5062   }
5063 
5064   tok::TokenKind Kind = Tok.getKind();
5065 
5066   if (D.getDeclSpec().isTypeSpecPipe() && !isPipeDeclerator(D)) {
5067     DeclSpec DS(AttrFactory);
5068     ParseTypeQualifierListOpt(DS);
5069 
5070     D.AddTypeInfo(
5071         DeclaratorChunk::getPipe(DS.getTypeQualifiers(), DS.getPipeLoc()),
5072         DS.getAttributes(), SourceLocation());
5073   }
5074 
5075   // Not a pointer, C++ reference, or block.
5076   if (!isPtrOperatorToken(Kind, getLangOpts(), D.getContext())) {
5077     if (DirectDeclParser)
5078       (this->*DirectDeclParser)(D);
5079     return;
5080   }
5081 
5082   // Otherwise, '*' -> pointer, '^' -> block, '&' -> lvalue reference,
5083   // '&&' -> rvalue reference
5084   SourceLocation Loc = ConsumeToken();  // Eat the *, ^, & or &&.
5085   D.SetRangeEnd(Loc);
5086 
5087   if (Kind == tok::star || Kind == tok::caret) {
5088     // Is a pointer.
5089     DeclSpec DS(AttrFactory);
5090 
5091     // GNU attributes are not allowed here in a new-type-id, but Declspec and
5092     // C++11 attributes are allowed.
5093     unsigned Reqs = AR_CXX11AttributesParsed | AR_DeclspecAttributesParsed |
5094                             ((D.getContext() != Declarator::CXXNewContext)
5095                                  ? AR_GNUAttributesParsed
5096                                  : AR_GNUAttributesParsedAndRejected);
5097     ParseTypeQualifierListOpt(DS, Reqs, true, !D.mayOmitIdentifier());
5098     D.ExtendWithDeclSpec(DS);
5099 
5100     // Recursively parse the declarator.
5101     ParseDeclaratorInternal(D, DirectDeclParser);
5102     if (Kind == tok::star)
5103       // Remember that we parsed a pointer type, and remember the type-quals.
5104       D.AddTypeInfo(DeclaratorChunk::getPointer(DS.getTypeQualifiers(), Loc,
5105                                                 DS.getConstSpecLoc(),
5106                                                 DS.getVolatileSpecLoc(),
5107                                                 DS.getRestrictSpecLoc(),
5108                                                 DS.getAtomicSpecLoc(),
5109                                                 DS.getUnalignedSpecLoc()),
5110                     DS.getAttributes(),
5111                     SourceLocation());
5112     else
5113       // Remember that we parsed a Block type, and remember the type-quals.
5114       D.AddTypeInfo(DeclaratorChunk::getBlockPointer(DS.getTypeQualifiers(),
5115                                                      Loc),
5116                     DS.getAttributes(),
5117                     SourceLocation());
5118   } else {
5119     // Is a reference
5120     DeclSpec DS(AttrFactory);
5121 
5122     // Complain about rvalue references in C++03, but then go on and build
5123     // the declarator.
5124     if (Kind == tok::ampamp)
5125       Diag(Loc, getLangOpts().CPlusPlus11 ?
5126            diag::warn_cxx98_compat_rvalue_reference :
5127            diag::ext_rvalue_reference);
5128 
5129     // GNU-style and C++11 attributes are allowed here, as is restrict.
5130     ParseTypeQualifierListOpt(DS);
5131     D.ExtendWithDeclSpec(DS);
5132 
5133     // C++ 8.3.2p1: cv-qualified references are ill-formed except when the
5134     // cv-qualifiers are introduced through the use of a typedef or of a
5135     // template type argument, in which case the cv-qualifiers are ignored.
5136     if (DS.getTypeQualifiers() != DeclSpec::TQ_unspecified) {
5137       if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
5138         Diag(DS.getConstSpecLoc(),
5139              diag::err_invalid_reference_qualifier_application) << "const";
5140       if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
5141         Diag(DS.getVolatileSpecLoc(),
5142              diag::err_invalid_reference_qualifier_application) << "volatile";
5143       // 'restrict' is permitted as an extension.
5144       if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
5145         Diag(DS.getAtomicSpecLoc(),
5146              diag::err_invalid_reference_qualifier_application) << "_Atomic";
5147     }
5148 
5149     // Recursively parse the declarator.
5150     ParseDeclaratorInternal(D, DirectDeclParser);
5151 
5152     if (D.getNumTypeObjects() > 0) {
5153       // C++ [dcl.ref]p4: There shall be no references to references.
5154       DeclaratorChunk& InnerChunk = D.getTypeObject(D.getNumTypeObjects() - 1);
5155       if (InnerChunk.Kind == DeclaratorChunk::Reference) {
5156         if (const IdentifierInfo *II = D.getIdentifier())
5157           Diag(InnerChunk.Loc, diag::err_illegal_decl_reference_to_reference)
5158            << II;
5159         else
5160           Diag(InnerChunk.Loc, diag::err_illegal_decl_reference_to_reference)
5161             << "type name";
5162 
5163         // Once we've complained about the reference-to-reference, we
5164         // can go ahead and build the (technically ill-formed)
5165         // declarator: reference collapsing will take care of it.
5166       }
5167     }
5168 
5169     // Remember that we parsed a reference type.
5170     D.AddTypeInfo(DeclaratorChunk::getReference(DS.getTypeQualifiers(), Loc,
5171                                                 Kind == tok::amp),
5172                   DS.getAttributes(),
5173                   SourceLocation());
5174   }
5175 }
5176 
5177 // When correcting from misplaced brackets before the identifier, the location
5178 // is saved inside the declarator so that other diagnostic messages can use
5179 // them.  This extracts and returns that location, or returns the provided
5180 // location if a stored location does not exist.
5181 static SourceLocation getMissingDeclaratorIdLoc(Declarator &D,
5182                                                 SourceLocation Loc) {
5183   if (D.getName().StartLocation.isInvalid() &&
5184       D.getName().EndLocation.isValid())
5185     return D.getName().EndLocation;
5186 
5187   return Loc;
5188 }
5189 
5190 /// ParseDirectDeclarator
5191 ///       direct-declarator: [C99 6.7.5]
5192 /// [C99]   identifier
5193 ///         '(' declarator ')'
5194 /// [GNU]   '(' attributes declarator ')'
5195 /// [C90]   direct-declarator '[' constant-expression[opt] ']'
5196 /// [C99]   direct-declarator '[' type-qual-list[opt] assignment-expr[opt] ']'
5197 /// [C99]   direct-declarator '[' 'static' type-qual-list[opt] assign-expr ']'
5198 /// [C99]   direct-declarator '[' type-qual-list 'static' assignment-expr ']'
5199 /// [C99]   direct-declarator '[' type-qual-list[opt] '*' ']'
5200 /// [C++11] direct-declarator '[' constant-expression[opt] ']'
5201 ///                    attribute-specifier-seq[opt]
5202 ///         direct-declarator '(' parameter-type-list ')'
5203 ///         direct-declarator '(' identifier-list[opt] ')'
5204 /// [GNU]   direct-declarator '(' parameter-forward-declarations
5205 ///                    parameter-type-list[opt] ')'
5206 /// [C++]   direct-declarator '(' parameter-declaration-clause ')'
5207 ///                    cv-qualifier-seq[opt] exception-specification[opt]
5208 /// [C++11] direct-declarator '(' parameter-declaration-clause ')'
5209 ///                    attribute-specifier-seq[opt] cv-qualifier-seq[opt]
5210 ///                    ref-qualifier[opt] exception-specification[opt]
5211 /// [C++]   declarator-id
5212 /// [C++11] declarator-id attribute-specifier-seq[opt]
5213 ///
5214 ///       declarator-id: [C++ 8]
5215 ///         '...'[opt] id-expression
5216 ///         '::'[opt] nested-name-specifier[opt] type-name
5217 ///
5218 ///       id-expression: [C++ 5.1]
5219 ///         unqualified-id
5220 ///         qualified-id
5221 ///
5222 ///       unqualified-id: [C++ 5.1]
5223 ///         identifier
5224 ///         operator-function-id
5225 ///         conversion-function-id
5226 ///          '~' class-name
5227 ///         template-id
5228 ///
5229 /// C++17 adds the following, which we also handle here:
5230 ///
5231 ///       simple-declaration:
5232 ///         <decl-spec> '[' identifier-list ']' brace-or-equal-initializer ';'
5233 ///
5234 /// Note, any additional constructs added here may need corresponding changes
5235 /// in isConstructorDeclarator.
5236 void Parser::ParseDirectDeclarator(Declarator &D) {
5237   DeclaratorScopeObj DeclScopeObj(*this, D.getCXXScopeSpec());
5238 
5239   if (getLangOpts().CPlusPlus && D.mayHaveIdentifier()) {
5240     // This might be a C++17 structured binding.
5241     if (Tok.is(tok::l_square) && !D.mayOmitIdentifier() &&
5242         D.getCXXScopeSpec().isEmpty())
5243       return ParseDecompositionDeclarator(D);
5244 
5245     // Don't parse FOO:BAR as if it were a typo for FOO::BAR inside a class, in
5246     // this context it is a bitfield. Also in range-based for statement colon
5247     // may delimit for-range-declaration.
5248     ColonProtectionRAIIObject X(*this,
5249                                 D.getContext() == Declarator::MemberContext ||
5250                                     (D.getContext() == Declarator::ForContext &&
5251                                      getLangOpts().CPlusPlus11));
5252 
5253     // ParseDeclaratorInternal might already have parsed the scope.
5254     if (D.getCXXScopeSpec().isEmpty()) {
5255       bool EnteringContext = D.getContext() == Declarator::FileContext ||
5256                              D.getContext() == Declarator::MemberContext;
5257       ParseOptionalCXXScopeSpecifier(D.getCXXScopeSpec(), nullptr,
5258                                      EnteringContext);
5259     }
5260 
5261     if (D.getCXXScopeSpec().isValid()) {
5262       if (Actions.ShouldEnterDeclaratorScope(getCurScope(),
5263                                              D.getCXXScopeSpec()))
5264         // Change the declaration context for name lookup, until this function
5265         // is exited (and the declarator has been parsed).
5266         DeclScopeObj.EnterDeclaratorScope();
5267       else if (getObjCDeclContext()) {
5268         // Ensure that we don't interpret the next token as an identifier when
5269         // dealing with declarations in an Objective-C container.
5270         D.SetIdentifier(nullptr, Tok.getLocation());
5271         D.setInvalidType(true);
5272         ConsumeToken();
5273         goto PastIdentifier;
5274       }
5275     }
5276 
5277     // C++0x [dcl.fct]p14:
5278     //   There is a syntactic ambiguity when an ellipsis occurs at the end of a
5279     //   parameter-declaration-clause without a preceding comma. In this case,
5280     //   the ellipsis is parsed as part of the abstract-declarator if the type
5281     //   of the parameter either names a template parameter pack that has not
5282     //   been expanded or contains auto; otherwise, it is parsed as part of the
5283     //   parameter-declaration-clause.
5284     if (Tok.is(tok::ellipsis) && D.getCXXScopeSpec().isEmpty() &&
5285         !((D.getContext() == Declarator::PrototypeContext ||
5286            D.getContext() == Declarator::LambdaExprParameterContext ||
5287            D.getContext() == Declarator::BlockLiteralContext) &&
5288           NextToken().is(tok::r_paren) &&
5289           !D.hasGroupingParens() &&
5290           !Actions.containsUnexpandedParameterPacks(D) &&
5291           D.getDeclSpec().getTypeSpecType() != TST_auto)) {
5292       SourceLocation EllipsisLoc = ConsumeToken();
5293       if (isPtrOperatorToken(Tok.getKind(), getLangOpts(), D.getContext())) {
5294         // The ellipsis was put in the wrong place. Recover, and explain to
5295         // the user what they should have done.
5296         ParseDeclarator(D);
5297         if (EllipsisLoc.isValid())
5298           DiagnoseMisplacedEllipsisInDeclarator(EllipsisLoc, D);
5299         return;
5300       } else
5301         D.setEllipsisLoc(EllipsisLoc);
5302 
5303       // The ellipsis can't be followed by a parenthesized declarator. We
5304       // check for that in ParseParenDeclarator, after we have disambiguated
5305       // the l_paren token.
5306     }
5307 
5308     if (Tok.isOneOf(tok::identifier, tok::kw_operator, tok::annot_template_id,
5309                     tok::tilde)) {
5310       // We found something that indicates the start of an unqualified-id.
5311       // Parse that unqualified-id.
5312       bool AllowConstructorName;
5313       if (D.getDeclSpec().hasTypeSpecifier())
5314         AllowConstructorName = false;
5315       else if (D.getCXXScopeSpec().isSet())
5316         AllowConstructorName =
5317           (D.getContext() == Declarator::FileContext ||
5318            D.getContext() == Declarator::MemberContext);
5319       else
5320         AllowConstructorName = (D.getContext() == Declarator::MemberContext);
5321 
5322       SourceLocation TemplateKWLoc;
5323       bool HadScope = D.getCXXScopeSpec().isValid();
5324       if (ParseUnqualifiedId(D.getCXXScopeSpec(),
5325                              /*EnteringContext=*/true,
5326                              /*AllowDestructorName=*/true, AllowConstructorName,
5327                              nullptr, TemplateKWLoc, D.getName()) ||
5328           // Once we're past the identifier, if the scope was bad, mark the
5329           // whole declarator bad.
5330           D.getCXXScopeSpec().isInvalid()) {
5331         D.SetIdentifier(nullptr, Tok.getLocation());
5332         D.setInvalidType(true);
5333       } else {
5334         // ParseUnqualifiedId might have parsed a scope specifier during error
5335         // recovery. If it did so, enter that scope.
5336         if (!HadScope && D.getCXXScopeSpec().isValid() &&
5337             Actions.ShouldEnterDeclaratorScope(getCurScope(),
5338                                                D.getCXXScopeSpec()))
5339           DeclScopeObj.EnterDeclaratorScope();
5340 
5341         // Parsed the unqualified-id; update range information and move along.
5342         if (D.getSourceRange().getBegin().isInvalid())
5343           D.SetRangeBegin(D.getName().getSourceRange().getBegin());
5344         D.SetRangeEnd(D.getName().getSourceRange().getEnd());
5345       }
5346       goto PastIdentifier;
5347     }
5348 
5349     if (D.getCXXScopeSpec().isNotEmpty()) {
5350       // We have a scope specifier but no following unqualified-id.
5351       Diag(PP.getLocForEndOfToken(D.getCXXScopeSpec().getEndLoc()),
5352            diag::err_expected_unqualified_id)
5353           << /*C++*/1;
5354       D.SetIdentifier(nullptr, Tok.getLocation());
5355       goto PastIdentifier;
5356     }
5357   } else if (Tok.is(tok::identifier) && D.mayHaveIdentifier()) {
5358     assert(!getLangOpts().CPlusPlus &&
5359            "There's a C++-specific check for tok::identifier above");
5360     assert(Tok.getIdentifierInfo() && "Not an identifier?");
5361     D.SetIdentifier(Tok.getIdentifierInfo(), Tok.getLocation());
5362     D.SetRangeEnd(Tok.getLocation());
5363     ConsumeToken();
5364     goto PastIdentifier;
5365   } else if (Tok.is(tok::identifier) && D.diagnoseIdentifier()) {
5366     // A virt-specifier isn't treated as an identifier if it appears after a
5367     // trailing-return-type.
5368     if (D.getContext() != Declarator::TrailingReturnContext ||
5369         !isCXX11VirtSpecifier(Tok)) {
5370       Diag(Tok.getLocation(), diag::err_unexpected_unqualified_id)
5371         << FixItHint::CreateRemoval(Tok.getLocation());
5372       D.SetIdentifier(nullptr, Tok.getLocation());
5373       ConsumeToken();
5374       goto PastIdentifier;
5375     }
5376   }
5377 
5378   if (Tok.is(tok::l_paren)) {
5379     // direct-declarator: '(' declarator ')'
5380     // direct-declarator: '(' attributes declarator ')'
5381     // Example: 'char (*X)'   or 'int (*XX)(void)'
5382     ParseParenDeclarator(D);
5383 
5384     // If the declarator was parenthesized, we entered the declarator
5385     // scope when parsing the parenthesized declarator, then exited
5386     // the scope already. Re-enter the scope, if we need to.
5387     if (D.getCXXScopeSpec().isSet()) {
5388       // If there was an error parsing parenthesized declarator, declarator
5389       // scope may have been entered before. Don't do it again.
5390       if (!D.isInvalidType() &&
5391           Actions.ShouldEnterDeclaratorScope(getCurScope(),
5392                                              D.getCXXScopeSpec()))
5393         // Change the declaration context for name lookup, until this function
5394         // is exited (and the declarator has been parsed).
5395         DeclScopeObj.EnterDeclaratorScope();
5396     }
5397   } else if (D.mayOmitIdentifier()) {
5398     // This could be something simple like "int" (in which case the declarator
5399     // portion is empty), if an abstract-declarator is allowed.
5400     D.SetIdentifier(nullptr, Tok.getLocation());
5401 
5402     // The grammar for abstract-pack-declarator does not allow grouping parens.
5403     // FIXME: Revisit this once core issue 1488 is resolved.
5404     if (D.hasEllipsis() && D.hasGroupingParens())
5405       Diag(PP.getLocForEndOfToken(D.getEllipsisLoc()),
5406            diag::ext_abstract_pack_declarator_parens);
5407   } else {
5408     if (Tok.getKind() == tok::annot_pragma_parser_crash)
5409       LLVM_BUILTIN_TRAP;
5410     if (Tok.is(tok::l_square))
5411       return ParseMisplacedBracketDeclarator(D);
5412     if (D.getContext() == Declarator::MemberContext) {
5413       Diag(getMissingDeclaratorIdLoc(D, Tok.getLocation()),
5414            diag::err_expected_member_name_or_semi)
5415           << (D.getDeclSpec().isEmpty() ? SourceRange()
5416                                         : D.getDeclSpec().getSourceRange());
5417     } else if (getLangOpts().CPlusPlus) {
5418       if (Tok.isOneOf(tok::period, tok::arrow))
5419         Diag(Tok, diag::err_invalid_operator_on_type) << Tok.is(tok::arrow);
5420       else {
5421         SourceLocation Loc = D.getCXXScopeSpec().getEndLoc();
5422         if (Tok.isAtStartOfLine() && Loc.isValid())
5423           Diag(PP.getLocForEndOfToken(Loc), diag::err_expected_unqualified_id)
5424               << getLangOpts().CPlusPlus;
5425         else
5426           Diag(getMissingDeclaratorIdLoc(D, Tok.getLocation()),
5427                diag::err_expected_unqualified_id)
5428               << getLangOpts().CPlusPlus;
5429       }
5430     } else {
5431       Diag(getMissingDeclaratorIdLoc(D, Tok.getLocation()),
5432            diag::err_expected_either)
5433           << tok::identifier << tok::l_paren;
5434     }
5435     D.SetIdentifier(nullptr, Tok.getLocation());
5436     D.setInvalidType(true);
5437   }
5438 
5439  PastIdentifier:
5440   assert(D.isPastIdentifier() &&
5441          "Haven't past the location of the identifier yet?");
5442 
5443   // Don't parse attributes unless we have parsed an unparenthesized name.
5444   if (D.hasName() && !D.getNumTypeObjects())
5445     MaybeParseCXX11Attributes(D);
5446 
5447   while (1) {
5448     if (Tok.is(tok::l_paren)) {
5449       // Enter function-declaration scope, limiting any declarators to the
5450       // function prototype scope, including parameter declarators.
5451       ParseScope PrototypeScope(this,
5452                                 Scope::FunctionPrototypeScope|Scope::DeclScope|
5453                                 (D.isFunctionDeclaratorAFunctionDeclaration()
5454                                    ? Scope::FunctionDeclarationScope : 0));
5455 
5456       // The paren may be part of a C++ direct initializer, eg. "int x(1);".
5457       // In such a case, check if we actually have a function declarator; if it
5458       // is not, the declarator has been fully parsed.
5459       bool IsAmbiguous = false;
5460       if (getLangOpts().CPlusPlus && D.mayBeFollowedByCXXDirectInit()) {
5461         // The name of the declarator, if any, is tentatively declared within
5462         // a possible direct initializer.
5463         TentativelyDeclaredIdentifiers.push_back(D.getIdentifier());
5464         bool IsFunctionDecl = isCXXFunctionDeclarator(&IsAmbiguous);
5465         TentativelyDeclaredIdentifiers.pop_back();
5466         if (!IsFunctionDecl)
5467           break;
5468       }
5469       ParsedAttributes attrs(AttrFactory);
5470       BalancedDelimiterTracker T(*this, tok::l_paren);
5471       T.consumeOpen();
5472       ParseFunctionDeclarator(D, attrs, T, IsAmbiguous);
5473       PrototypeScope.Exit();
5474     } else if (Tok.is(tok::l_square)) {
5475       ParseBracketDeclarator(D);
5476     } else {
5477       break;
5478     }
5479   }
5480 }
5481 
5482 void Parser::ParseDecompositionDeclarator(Declarator &D) {
5483   assert(Tok.is(tok::l_square));
5484 
5485   // If this doesn't look like a structured binding, maybe it's a misplaced
5486   // array declarator.
5487   // FIXME: Consume the l_square first so we don't need extra lookahead for
5488   // this.
5489   if (!(NextToken().is(tok::identifier) &&
5490         GetLookAheadToken(2).isOneOf(tok::comma, tok::r_square)) &&
5491       !(NextToken().is(tok::r_square) &&
5492         GetLookAheadToken(2).isOneOf(tok::equal, tok::l_brace)))
5493     return ParseMisplacedBracketDeclarator(D);
5494 
5495   BalancedDelimiterTracker T(*this, tok::l_square);
5496   T.consumeOpen();
5497 
5498   SmallVector<DecompositionDeclarator::Binding, 32> Bindings;
5499   while (Tok.isNot(tok::r_square)) {
5500     if (!Bindings.empty()) {
5501       if (Tok.is(tok::comma))
5502         ConsumeToken();
5503       else {
5504         if (Tok.is(tok::identifier)) {
5505           SourceLocation EndLoc = getEndOfPreviousToken();
5506           Diag(EndLoc, diag::err_expected)
5507               << tok::comma << FixItHint::CreateInsertion(EndLoc, ",");
5508         } else {
5509           Diag(Tok, diag::err_expected_comma_or_rsquare);
5510         }
5511 
5512         SkipUntil(tok::r_square, tok::comma, tok::identifier,
5513                   StopAtSemi | StopBeforeMatch);
5514         if (Tok.is(tok::comma))
5515           ConsumeToken();
5516         else if (Tok.isNot(tok::identifier))
5517           break;
5518       }
5519     }
5520 
5521     if (Tok.isNot(tok::identifier)) {
5522       Diag(Tok, diag::err_expected) << tok::identifier;
5523       break;
5524     }
5525 
5526     Bindings.push_back({Tok.getIdentifierInfo(), Tok.getLocation()});
5527     ConsumeToken();
5528   }
5529 
5530   if (Tok.isNot(tok::r_square))
5531     // We've already diagnosed a problem here.
5532     T.skipToEnd();
5533   else {
5534     // C++17 does not allow the identifier-list in a structured binding
5535     // to be empty.
5536     if (Bindings.empty())
5537       Diag(Tok.getLocation(), diag::ext_decomp_decl_empty);
5538 
5539     T.consumeClose();
5540   }
5541 
5542   return D.setDecompositionBindings(T.getOpenLocation(), Bindings,
5543                                     T.getCloseLocation());
5544 }
5545 
5546 /// ParseParenDeclarator - We parsed the declarator D up to a paren.  This is
5547 /// only called before the identifier, so these are most likely just grouping
5548 /// parens for precedence.  If we find that these are actually function
5549 /// parameter parens in an abstract-declarator, we call ParseFunctionDeclarator.
5550 ///
5551 ///       direct-declarator:
5552 ///         '(' declarator ')'
5553 /// [GNU]   '(' attributes declarator ')'
5554 ///         direct-declarator '(' parameter-type-list ')'
5555 ///         direct-declarator '(' identifier-list[opt] ')'
5556 /// [GNU]   direct-declarator '(' parameter-forward-declarations
5557 ///                    parameter-type-list[opt] ')'
5558 ///
5559 void Parser::ParseParenDeclarator(Declarator &D) {
5560   BalancedDelimiterTracker T(*this, tok::l_paren);
5561   T.consumeOpen();
5562 
5563   assert(!D.isPastIdentifier() && "Should be called before passing identifier");
5564 
5565   // Eat any attributes before we look at whether this is a grouping or function
5566   // declarator paren.  If this is a grouping paren, the attribute applies to
5567   // the type being built up, for example:
5568   //     int (__attribute__(()) *x)(long y)
5569   // If this ends up not being a grouping paren, the attribute applies to the
5570   // first argument, for example:
5571   //     int (__attribute__(()) int x)
5572   // In either case, we need to eat any attributes to be able to determine what
5573   // sort of paren this is.
5574   //
5575   ParsedAttributes attrs(AttrFactory);
5576   bool RequiresArg = false;
5577   if (Tok.is(tok::kw___attribute)) {
5578     ParseGNUAttributes(attrs);
5579 
5580     // We require that the argument list (if this is a non-grouping paren) be
5581     // present even if the attribute list was empty.
5582     RequiresArg = true;
5583   }
5584 
5585   // Eat any Microsoft extensions.
5586   ParseMicrosoftTypeAttributes(attrs);
5587 
5588   // Eat any Borland extensions.
5589   if  (Tok.is(tok::kw___pascal))
5590     ParseBorlandTypeAttributes(attrs);
5591 
5592   // If we haven't past the identifier yet (or where the identifier would be
5593   // stored, if this is an abstract declarator), then this is probably just
5594   // grouping parens. However, if this could be an abstract-declarator, then
5595   // this could also be the start of function arguments (consider 'void()').
5596   bool isGrouping;
5597 
5598   if (!D.mayOmitIdentifier()) {
5599     // If this can't be an abstract-declarator, this *must* be a grouping
5600     // paren, because we haven't seen the identifier yet.
5601     isGrouping = true;
5602   } else if (Tok.is(tok::r_paren) ||           // 'int()' is a function.
5603              (getLangOpts().CPlusPlus && Tok.is(tok::ellipsis) &&
5604               NextToken().is(tok::r_paren)) || // C++ int(...)
5605              isDeclarationSpecifier() ||       // 'int(int)' is a function.
5606              isCXX11AttributeSpecifier()) {    // 'int([[]]int)' is a function.
5607     // This handles C99 6.7.5.3p11: in "typedef int X; void foo(X)", X is
5608     // considered to be a type, not a K&R identifier-list.
5609     isGrouping = false;
5610   } else {
5611     // Otherwise, this is a grouping paren, e.g. 'int (*X)' or 'int(X)'.
5612     isGrouping = true;
5613   }
5614 
5615   // If this is a grouping paren, handle:
5616   // direct-declarator: '(' declarator ')'
5617   // direct-declarator: '(' attributes declarator ')'
5618   if (isGrouping) {
5619     SourceLocation EllipsisLoc = D.getEllipsisLoc();
5620     D.setEllipsisLoc(SourceLocation());
5621 
5622     bool hadGroupingParens = D.hasGroupingParens();
5623     D.setGroupingParens(true);
5624     ParseDeclaratorInternal(D, &Parser::ParseDirectDeclarator);
5625     // Match the ')'.
5626     T.consumeClose();
5627     D.AddTypeInfo(DeclaratorChunk::getParen(T.getOpenLocation(),
5628                                             T.getCloseLocation()),
5629                   attrs, T.getCloseLocation());
5630 
5631     D.setGroupingParens(hadGroupingParens);
5632 
5633     // An ellipsis cannot be placed outside parentheses.
5634     if (EllipsisLoc.isValid())
5635       DiagnoseMisplacedEllipsisInDeclarator(EllipsisLoc, D);
5636 
5637     return;
5638   }
5639 
5640   // Okay, if this wasn't a grouping paren, it must be the start of a function
5641   // argument list.  Recognize that this declarator will never have an
5642   // identifier (and remember where it would have been), then call into
5643   // ParseFunctionDeclarator to handle of argument list.
5644   D.SetIdentifier(nullptr, Tok.getLocation());
5645 
5646   // Enter function-declaration scope, limiting any declarators to the
5647   // function prototype scope, including parameter declarators.
5648   ParseScope PrototypeScope(this,
5649                             Scope::FunctionPrototypeScope | Scope::DeclScope |
5650                             (D.isFunctionDeclaratorAFunctionDeclaration()
5651                                ? Scope::FunctionDeclarationScope : 0));
5652   ParseFunctionDeclarator(D, attrs, T, false, RequiresArg);
5653   PrototypeScope.Exit();
5654 }
5655 
5656 /// ParseFunctionDeclarator - We are after the identifier and have parsed the
5657 /// declarator D up to a paren, which indicates that we are parsing function
5658 /// arguments.
5659 ///
5660 /// If FirstArgAttrs is non-null, then the caller parsed those arguments
5661 /// immediately after the open paren - they should be considered to be the
5662 /// first argument of a parameter.
5663 ///
5664 /// If RequiresArg is true, then the first argument of the function is required
5665 /// to be present and required to not be an identifier list.
5666 ///
5667 /// For C++, after the parameter-list, it also parses the cv-qualifier-seq[opt],
5668 /// (C++11) ref-qualifier[opt], exception-specification[opt],
5669 /// (C++11) attribute-specifier-seq[opt], and (C++11) trailing-return-type[opt].
5670 ///
5671 /// [C++11] exception-specification:
5672 ///           dynamic-exception-specification
5673 ///           noexcept-specification
5674 ///
5675 void Parser::ParseFunctionDeclarator(Declarator &D,
5676                                      ParsedAttributes &FirstArgAttrs,
5677                                      BalancedDelimiterTracker &Tracker,
5678                                      bool IsAmbiguous,
5679                                      bool RequiresArg) {
5680   assert(getCurScope()->isFunctionPrototypeScope() &&
5681          "Should call from a Function scope");
5682   // lparen is already consumed!
5683   assert(D.isPastIdentifier() && "Should not call before identifier!");
5684 
5685   // This should be true when the function has typed arguments.
5686   // Otherwise, it is treated as a K&R-style function.
5687   bool HasProto = false;
5688   // Build up an array of information about the parsed arguments.
5689   SmallVector<DeclaratorChunk::ParamInfo, 16> ParamInfo;
5690   // Remember where we see an ellipsis, if any.
5691   SourceLocation EllipsisLoc;
5692 
5693   DeclSpec DS(AttrFactory);
5694   bool RefQualifierIsLValueRef = true;
5695   SourceLocation RefQualifierLoc;
5696   SourceLocation ConstQualifierLoc;
5697   SourceLocation VolatileQualifierLoc;
5698   SourceLocation RestrictQualifierLoc;
5699   ExceptionSpecificationType ESpecType = EST_None;
5700   SourceRange ESpecRange;
5701   SmallVector<ParsedType, 2> DynamicExceptions;
5702   SmallVector<SourceRange, 2> DynamicExceptionRanges;
5703   ExprResult NoexceptExpr;
5704   CachedTokens *ExceptionSpecTokens = nullptr;
5705   ParsedAttributes FnAttrs(AttrFactory);
5706   TypeResult TrailingReturnType;
5707 
5708   /* LocalEndLoc is the end location for the local FunctionTypeLoc.
5709      EndLoc is the end location for the function declarator.
5710      They differ for trailing return types. */
5711   SourceLocation StartLoc, LocalEndLoc, EndLoc;
5712   SourceLocation LParenLoc, RParenLoc;
5713   LParenLoc = Tracker.getOpenLocation();
5714   StartLoc = LParenLoc;
5715 
5716   if (isFunctionDeclaratorIdentifierList()) {
5717     if (RequiresArg)
5718       Diag(Tok, diag::err_argument_required_after_attribute);
5719 
5720     ParseFunctionDeclaratorIdentifierList(D, ParamInfo);
5721 
5722     Tracker.consumeClose();
5723     RParenLoc = Tracker.getCloseLocation();
5724     LocalEndLoc = RParenLoc;
5725     EndLoc = RParenLoc;
5726   } else {
5727     if (Tok.isNot(tok::r_paren))
5728       ParseParameterDeclarationClause(D, FirstArgAttrs, ParamInfo,
5729                                       EllipsisLoc);
5730     else if (RequiresArg)
5731       Diag(Tok, diag::err_argument_required_after_attribute);
5732 
5733     HasProto = ParamInfo.size() || getLangOpts().CPlusPlus;
5734 
5735     // If we have the closing ')', eat it.
5736     Tracker.consumeClose();
5737     RParenLoc = Tracker.getCloseLocation();
5738     LocalEndLoc = RParenLoc;
5739     EndLoc = RParenLoc;
5740 
5741     if (getLangOpts().CPlusPlus) {
5742       // FIXME: Accept these components in any order, and produce fixits to
5743       // correct the order if the user gets it wrong. Ideally we should deal
5744       // with the pure-specifier in the same way.
5745 
5746       // Parse cv-qualifier-seq[opt].
5747       ParseTypeQualifierListOpt(DS, AR_NoAttributesParsed,
5748                                 /*AtomicAllowed*/ false);
5749       if (!DS.getSourceRange().getEnd().isInvalid()) {
5750         EndLoc = DS.getSourceRange().getEnd();
5751         ConstQualifierLoc = DS.getConstSpecLoc();
5752         VolatileQualifierLoc = DS.getVolatileSpecLoc();
5753         RestrictQualifierLoc = DS.getRestrictSpecLoc();
5754       }
5755 
5756       // Parse ref-qualifier[opt].
5757       if (ParseRefQualifier(RefQualifierIsLValueRef, RefQualifierLoc))
5758         EndLoc = RefQualifierLoc;
5759 
5760       // C++11 [expr.prim.general]p3:
5761       //   If a declaration declares a member function or member function
5762       //   template of a class X, the expression this is a prvalue of type
5763       //   "pointer to cv-qualifier-seq X" between the optional cv-qualifer-seq
5764       //   and the end of the function-definition, member-declarator, or
5765       //   declarator.
5766       // FIXME: currently, "static" case isn't handled correctly.
5767       bool IsCXX11MemberFunction =
5768         getLangOpts().CPlusPlus11 &&
5769         D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef &&
5770         (D.getContext() == Declarator::MemberContext
5771          ? !D.getDeclSpec().isFriendSpecified()
5772          : D.getContext() == Declarator::FileContext &&
5773            D.getCXXScopeSpec().isValid() &&
5774            Actions.CurContext->isRecord());
5775       Sema::CXXThisScopeRAII ThisScope(Actions,
5776                                dyn_cast<CXXRecordDecl>(Actions.CurContext),
5777                                DS.getTypeQualifiers() |
5778                                (D.getDeclSpec().isConstexprSpecified() &&
5779                                 !getLangOpts().CPlusPlus14
5780                                   ? Qualifiers::Const : 0),
5781                                IsCXX11MemberFunction);
5782 
5783       // Parse exception-specification[opt].
5784       bool Delayed = D.isFirstDeclarationOfMember() &&
5785                      D.isFunctionDeclaratorAFunctionDeclaration();
5786       if (Delayed && Actions.isLibstdcxxEagerExceptionSpecHack(D) &&
5787           GetLookAheadToken(0).is(tok::kw_noexcept) &&
5788           GetLookAheadToken(1).is(tok::l_paren) &&
5789           GetLookAheadToken(2).is(tok::kw_noexcept) &&
5790           GetLookAheadToken(3).is(tok::l_paren) &&
5791           GetLookAheadToken(4).is(tok::identifier) &&
5792           GetLookAheadToken(4).getIdentifierInfo()->isStr("swap")) {
5793         // HACK: We've got an exception-specification
5794         //   noexcept(noexcept(swap(...)))
5795         // or
5796         //   noexcept(noexcept(swap(...)) && noexcept(swap(...)))
5797         // on a 'swap' member function. This is a libstdc++ bug; the lookup
5798         // for 'swap' will only find the function we're currently declaring,
5799         // whereas it expects to find a non-member swap through ADL. Turn off
5800         // delayed parsing to give it a chance to find what it expects.
5801         Delayed = false;
5802       }
5803       ESpecType = tryParseExceptionSpecification(Delayed,
5804                                                  ESpecRange,
5805                                                  DynamicExceptions,
5806                                                  DynamicExceptionRanges,
5807                                                  NoexceptExpr,
5808                                                  ExceptionSpecTokens);
5809       if (ESpecType != EST_None)
5810         EndLoc = ESpecRange.getEnd();
5811 
5812       // Parse attribute-specifier-seq[opt]. Per DR 979 and DR 1297, this goes
5813       // after the exception-specification.
5814       MaybeParseCXX11Attributes(FnAttrs);
5815 
5816       // Parse trailing-return-type[opt].
5817       LocalEndLoc = EndLoc;
5818       if (getLangOpts().CPlusPlus11 && Tok.is(tok::arrow)) {
5819         Diag(Tok, diag::warn_cxx98_compat_trailing_return_type);
5820         if (D.getDeclSpec().getTypeSpecType() == TST_auto)
5821           StartLoc = D.getDeclSpec().getTypeSpecTypeLoc();
5822         LocalEndLoc = Tok.getLocation();
5823         SourceRange Range;
5824         TrailingReturnType = ParseTrailingReturnType(Range);
5825         EndLoc = Range.getEnd();
5826       }
5827     }
5828   }
5829 
5830   // Collect non-parameter declarations from the prototype if this is a function
5831   // declaration. They will be moved into the scope of the function. Only do
5832   // this in C and not C++, where the decls will continue to live in the
5833   // surrounding context.
5834   SmallVector<NamedDecl *, 0> DeclsInPrototype;
5835   if (getCurScope()->getFlags() & Scope::FunctionDeclarationScope &&
5836       !getLangOpts().CPlusPlus) {
5837     for (Decl *D : getCurScope()->decls()) {
5838       NamedDecl *ND = dyn_cast<NamedDecl>(D);
5839       if (!ND || isa<ParmVarDecl>(ND))
5840         continue;
5841       DeclsInPrototype.push_back(ND);
5842     }
5843   }
5844 
5845   // Remember that we parsed a function type, and remember the attributes.
5846   D.AddTypeInfo(DeclaratorChunk::getFunction(HasProto,
5847                                              IsAmbiguous,
5848                                              LParenLoc,
5849                                              ParamInfo.data(), ParamInfo.size(),
5850                                              EllipsisLoc, RParenLoc,
5851                                              DS.getTypeQualifiers(),
5852                                              RefQualifierIsLValueRef,
5853                                              RefQualifierLoc, ConstQualifierLoc,
5854                                              VolatileQualifierLoc,
5855                                              RestrictQualifierLoc,
5856                                              /*MutableLoc=*/SourceLocation(),
5857                                              ESpecType, ESpecRange,
5858                                              DynamicExceptions.data(),
5859                                              DynamicExceptionRanges.data(),
5860                                              DynamicExceptions.size(),
5861                                              NoexceptExpr.isUsable() ?
5862                                                NoexceptExpr.get() : nullptr,
5863                                              ExceptionSpecTokens,
5864                                              DeclsInPrototype,
5865                                              StartLoc, LocalEndLoc, D,
5866                                              TrailingReturnType),
5867                 FnAttrs, EndLoc);
5868 }
5869 
5870 /// ParseRefQualifier - Parses a member function ref-qualifier. Returns
5871 /// true if a ref-qualifier is found.
5872 bool Parser::ParseRefQualifier(bool &RefQualifierIsLValueRef,
5873                                SourceLocation &RefQualifierLoc) {
5874   if (Tok.isOneOf(tok::amp, tok::ampamp)) {
5875     Diag(Tok, getLangOpts().CPlusPlus11 ?
5876          diag::warn_cxx98_compat_ref_qualifier :
5877          diag::ext_ref_qualifier);
5878 
5879     RefQualifierIsLValueRef = Tok.is(tok::amp);
5880     RefQualifierLoc = ConsumeToken();
5881     return true;
5882   }
5883   return false;
5884 }
5885 
5886 /// isFunctionDeclaratorIdentifierList - This parameter list may have an
5887 /// identifier list form for a K&R-style function:  void foo(a,b,c)
5888 ///
5889 /// Note that identifier-lists are only allowed for normal declarators, not for
5890 /// abstract-declarators.
5891 bool Parser::isFunctionDeclaratorIdentifierList() {
5892   return !getLangOpts().CPlusPlus
5893          && Tok.is(tok::identifier)
5894          && !TryAltiVecVectorToken()
5895          // K&R identifier lists can't have typedefs as identifiers, per C99
5896          // 6.7.5.3p11.
5897          && (TryAnnotateTypeOrScopeToken() || !Tok.is(tok::annot_typename))
5898          // Identifier lists follow a really simple grammar: the identifiers can
5899          // be followed *only* by a ", identifier" or ")".  However, K&R
5900          // identifier lists are really rare in the brave new modern world, and
5901          // it is very common for someone to typo a type in a non-K&R style
5902          // list.  If we are presented with something like: "void foo(intptr x,
5903          // float y)", we don't want to start parsing the function declarator as
5904          // though it is a K&R style declarator just because intptr is an
5905          // invalid type.
5906          //
5907          // To handle this, we check to see if the token after the first
5908          // identifier is a "," or ")".  Only then do we parse it as an
5909          // identifier list.
5910          && (!Tok.is(tok::eof) &&
5911              (NextToken().is(tok::comma) || NextToken().is(tok::r_paren)));
5912 }
5913 
5914 /// ParseFunctionDeclaratorIdentifierList - While parsing a function declarator
5915 /// we found a K&R-style identifier list instead of a typed parameter list.
5916 ///
5917 /// After returning, ParamInfo will hold the parsed parameters.
5918 ///
5919 ///       identifier-list: [C99 6.7.5]
5920 ///         identifier
5921 ///         identifier-list ',' identifier
5922 ///
5923 void Parser::ParseFunctionDeclaratorIdentifierList(
5924        Declarator &D,
5925        SmallVectorImpl<DeclaratorChunk::ParamInfo> &ParamInfo) {
5926   // If there was no identifier specified for the declarator, either we are in
5927   // an abstract-declarator, or we are in a parameter declarator which was found
5928   // to be abstract.  In abstract-declarators, identifier lists are not valid:
5929   // diagnose this.
5930   if (!D.getIdentifier())
5931     Diag(Tok, diag::ext_ident_list_in_param);
5932 
5933   // Maintain an efficient lookup of params we have seen so far.
5934   llvm::SmallSet<const IdentifierInfo*, 16> ParamsSoFar;
5935 
5936   do {
5937     // If this isn't an identifier, report the error and skip until ')'.
5938     if (Tok.isNot(tok::identifier)) {
5939       Diag(Tok, diag::err_expected) << tok::identifier;
5940       SkipUntil(tok::r_paren, StopAtSemi | StopBeforeMatch);
5941       // Forget we parsed anything.
5942       ParamInfo.clear();
5943       return;
5944     }
5945 
5946     IdentifierInfo *ParmII = Tok.getIdentifierInfo();
5947 
5948     // Reject 'typedef int y; int test(x, y)', but continue parsing.
5949     if (Actions.getTypeName(*ParmII, Tok.getLocation(), getCurScope()))
5950       Diag(Tok, diag::err_unexpected_typedef_ident) << ParmII;
5951 
5952     // Verify that the argument identifier has not already been mentioned.
5953     if (!ParamsSoFar.insert(ParmII).second) {
5954       Diag(Tok, diag::err_param_redefinition) << ParmII;
5955     } else {
5956       // Remember this identifier in ParamInfo.
5957       ParamInfo.push_back(DeclaratorChunk::ParamInfo(ParmII,
5958                                                      Tok.getLocation(),
5959                                                      nullptr));
5960     }
5961 
5962     // Eat the identifier.
5963     ConsumeToken();
5964     // The list continues if we see a comma.
5965   } while (TryConsumeToken(tok::comma));
5966 }
5967 
5968 /// ParseParameterDeclarationClause - Parse a (possibly empty) parameter-list
5969 /// after the opening parenthesis. This function will not parse a K&R-style
5970 /// identifier list.
5971 ///
5972 /// D is the declarator being parsed.  If FirstArgAttrs is non-null, then the
5973 /// caller parsed those arguments immediately after the open paren - they should
5974 /// be considered to be part of the first parameter.
5975 ///
5976 /// After returning, ParamInfo will hold the parsed parameters. EllipsisLoc will
5977 /// be the location of the ellipsis, if any was parsed.
5978 ///
5979 ///       parameter-type-list: [C99 6.7.5]
5980 ///         parameter-list
5981 ///         parameter-list ',' '...'
5982 /// [C++]   parameter-list '...'
5983 ///
5984 ///       parameter-list: [C99 6.7.5]
5985 ///         parameter-declaration
5986 ///         parameter-list ',' parameter-declaration
5987 ///
5988 ///       parameter-declaration: [C99 6.7.5]
5989 ///         declaration-specifiers declarator
5990 /// [C++]   declaration-specifiers declarator '=' assignment-expression
5991 /// [C++11]                                       initializer-clause
5992 /// [GNU]   declaration-specifiers declarator attributes
5993 ///         declaration-specifiers abstract-declarator[opt]
5994 /// [C++]   declaration-specifiers abstract-declarator[opt]
5995 ///           '=' assignment-expression
5996 /// [GNU]   declaration-specifiers abstract-declarator[opt] attributes
5997 /// [C++11] attribute-specifier-seq parameter-declaration
5998 ///
5999 void Parser::ParseParameterDeclarationClause(
6000        Declarator &D,
6001        ParsedAttributes &FirstArgAttrs,
6002        SmallVectorImpl<DeclaratorChunk::ParamInfo> &ParamInfo,
6003        SourceLocation &EllipsisLoc) {
6004   do {
6005     // FIXME: Issue a diagnostic if we parsed an attribute-specifier-seq
6006     // before deciding this was a parameter-declaration-clause.
6007     if (TryConsumeToken(tok::ellipsis, EllipsisLoc))
6008       break;
6009 
6010     // Parse the declaration-specifiers.
6011     // Just use the ParsingDeclaration "scope" of the declarator.
6012     DeclSpec DS(AttrFactory);
6013 
6014     // Parse any C++11 attributes.
6015     MaybeParseCXX11Attributes(DS.getAttributes());
6016 
6017     // Skip any Microsoft attributes before a param.
6018     MaybeParseMicrosoftAttributes(DS.getAttributes());
6019 
6020     SourceLocation DSStart = Tok.getLocation();
6021 
6022     // If the caller parsed attributes for the first argument, add them now.
6023     // Take them so that we only apply the attributes to the first parameter.
6024     // FIXME: If we can leave the attributes in the token stream somehow, we can
6025     // get rid of a parameter (FirstArgAttrs) and this statement. It might be
6026     // too much hassle.
6027     DS.takeAttributesFrom(FirstArgAttrs);
6028 
6029     ParseDeclarationSpecifiers(DS);
6030 
6031 
6032     // Parse the declarator.  This is "PrototypeContext" or
6033     // "LambdaExprParameterContext", because we must accept either
6034     // 'declarator' or 'abstract-declarator' here.
6035     Declarator ParmDeclarator(DS,
6036               D.getContext() == Declarator::LambdaExprContext ?
6037                                   Declarator::LambdaExprParameterContext :
6038                                                 Declarator::PrototypeContext);
6039     ParseDeclarator(ParmDeclarator);
6040 
6041     // Parse GNU attributes, if present.
6042     MaybeParseGNUAttributes(ParmDeclarator);
6043 
6044     // Remember this parsed parameter in ParamInfo.
6045     IdentifierInfo *ParmII = ParmDeclarator.getIdentifier();
6046 
6047     // DefArgToks is used when the parsing of default arguments needs
6048     // to be delayed.
6049     std::unique_ptr<CachedTokens> DefArgToks;
6050 
6051     // If no parameter was specified, verify that *something* was specified,
6052     // otherwise we have a missing type and identifier.
6053     if (DS.isEmpty() && ParmDeclarator.getIdentifier() == nullptr &&
6054         ParmDeclarator.getNumTypeObjects() == 0) {
6055       // Completely missing, emit error.
6056       Diag(DSStart, diag::err_missing_param);
6057     } else {
6058       // Otherwise, we have something.  Add it and let semantic analysis try
6059       // to grok it and add the result to the ParamInfo we are building.
6060 
6061       // Last chance to recover from a misplaced ellipsis in an attempted
6062       // parameter pack declaration.
6063       if (Tok.is(tok::ellipsis) &&
6064           (NextToken().isNot(tok::r_paren) ||
6065            (!ParmDeclarator.getEllipsisLoc().isValid() &&
6066             !Actions.isUnexpandedParameterPackPermitted())) &&
6067           Actions.containsUnexpandedParameterPacks(ParmDeclarator))
6068         DiagnoseMisplacedEllipsisInDeclarator(ConsumeToken(), ParmDeclarator);
6069 
6070       // Inform the actions module about the parameter declarator, so it gets
6071       // added to the current scope.
6072       Decl *Param = Actions.ActOnParamDeclarator(getCurScope(), ParmDeclarator);
6073       // Parse the default argument, if any. We parse the default
6074       // arguments in all dialects; the semantic analysis in
6075       // ActOnParamDefaultArgument will reject the default argument in
6076       // C.
6077       if (Tok.is(tok::equal)) {
6078         SourceLocation EqualLoc = Tok.getLocation();
6079 
6080         // Parse the default argument
6081         if (D.getContext() == Declarator::MemberContext) {
6082           // If we're inside a class definition, cache the tokens
6083           // corresponding to the default argument. We'll actually parse
6084           // them when we see the end of the class definition.
6085           DefArgToks.reset(new CachedTokens);
6086 
6087           SourceLocation ArgStartLoc = NextToken().getLocation();
6088           if (!ConsumeAndStoreInitializer(*DefArgToks, CIK_DefaultArgument)) {
6089             DefArgToks.reset();
6090             Actions.ActOnParamDefaultArgumentError(Param, EqualLoc);
6091           } else {
6092             Actions.ActOnParamUnparsedDefaultArgument(Param, EqualLoc,
6093                                                       ArgStartLoc);
6094           }
6095         } else {
6096           // Consume the '='.
6097           ConsumeToken();
6098 
6099           // The argument isn't actually potentially evaluated unless it is
6100           // used.
6101           EnterExpressionEvaluationContext Eval(Actions,
6102                                               Sema::PotentiallyEvaluatedIfUsed,
6103                                                 Param);
6104 
6105           ExprResult DefArgResult;
6106           if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) {
6107             Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists);
6108             DefArgResult = ParseBraceInitializer();
6109           } else
6110             DefArgResult = ParseAssignmentExpression();
6111           DefArgResult = Actions.CorrectDelayedTyposInExpr(DefArgResult);
6112           if (DefArgResult.isInvalid()) {
6113             Actions.ActOnParamDefaultArgumentError(Param, EqualLoc);
6114             SkipUntil(tok::comma, tok::r_paren, StopAtSemi | StopBeforeMatch);
6115           } else {
6116             // Inform the actions module about the default argument
6117             Actions.ActOnParamDefaultArgument(Param, EqualLoc,
6118                                               DefArgResult.get());
6119           }
6120         }
6121       }
6122 
6123       ParamInfo.push_back(DeclaratorChunk::ParamInfo(ParmII,
6124                                           ParmDeclarator.getIdentifierLoc(),
6125                                           Param, std::move(DefArgToks)));
6126     }
6127 
6128     if (TryConsumeToken(tok::ellipsis, EllipsisLoc)) {
6129       if (!getLangOpts().CPlusPlus) {
6130         // We have ellipsis without a preceding ',', which is ill-formed
6131         // in C. Complain and provide the fix.
6132         Diag(EllipsisLoc, diag::err_missing_comma_before_ellipsis)
6133             << FixItHint::CreateInsertion(EllipsisLoc, ", ");
6134       } else if (ParmDeclarator.getEllipsisLoc().isValid() ||
6135                  Actions.containsUnexpandedParameterPacks(ParmDeclarator)) {
6136         // It looks like this was supposed to be a parameter pack. Warn and
6137         // point out where the ellipsis should have gone.
6138         SourceLocation ParmEllipsis = ParmDeclarator.getEllipsisLoc();
6139         Diag(EllipsisLoc, diag::warn_misplaced_ellipsis_vararg)
6140           << ParmEllipsis.isValid() << ParmEllipsis;
6141         if (ParmEllipsis.isValid()) {
6142           Diag(ParmEllipsis,
6143                diag::note_misplaced_ellipsis_vararg_existing_ellipsis);
6144         } else {
6145           Diag(ParmDeclarator.getIdentifierLoc(),
6146                diag::note_misplaced_ellipsis_vararg_add_ellipsis)
6147             << FixItHint::CreateInsertion(ParmDeclarator.getIdentifierLoc(),
6148                                           "...")
6149             << !ParmDeclarator.hasName();
6150         }
6151         Diag(EllipsisLoc, diag::note_misplaced_ellipsis_vararg_add_comma)
6152           << FixItHint::CreateInsertion(EllipsisLoc, ", ");
6153       }
6154 
6155       // We can't have any more parameters after an ellipsis.
6156       break;
6157     }
6158 
6159     // If the next token is a comma, consume it and keep reading arguments.
6160   } while (TryConsumeToken(tok::comma));
6161 }
6162 
6163 /// [C90]   direct-declarator '[' constant-expression[opt] ']'
6164 /// [C99]   direct-declarator '[' type-qual-list[opt] assignment-expr[opt] ']'
6165 /// [C99]   direct-declarator '[' 'static' type-qual-list[opt] assign-expr ']'
6166 /// [C99]   direct-declarator '[' type-qual-list 'static' assignment-expr ']'
6167 /// [C99]   direct-declarator '[' type-qual-list[opt] '*' ']'
6168 /// [C++11] direct-declarator '[' constant-expression[opt] ']'
6169 ///                           attribute-specifier-seq[opt]
6170 void Parser::ParseBracketDeclarator(Declarator &D) {
6171   if (CheckProhibitedCXX11Attribute())
6172     return;
6173 
6174   BalancedDelimiterTracker T(*this, tok::l_square);
6175   T.consumeOpen();
6176 
6177   // C array syntax has many features, but by-far the most common is [] and [4].
6178   // This code does a fast path to handle some of the most obvious cases.
6179   if (Tok.getKind() == tok::r_square) {
6180     T.consumeClose();
6181     ParsedAttributes attrs(AttrFactory);
6182     MaybeParseCXX11Attributes(attrs);
6183 
6184     // Remember that we parsed the empty array type.
6185     D.AddTypeInfo(DeclaratorChunk::getArray(0, false, false, nullptr,
6186                                             T.getOpenLocation(),
6187                                             T.getCloseLocation()),
6188                   attrs, T.getCloseLocation());
6189     return;
6190   } else if (Tok.getKind() == tok::numeric_constant &&
6191              GetLookAheadToken(1).is(tok::r_square)) {
6192     // [4] is very common.  Parse the numeric constant expression.
6193     ExprResult ExprRes(Actions.ActOnNumericConstant(Tok, getCurScope()));
6194     ConsumeToken();
6195 
6196     T.consumeClose();
6197     ParsedAttributes attrs(AttrFactory);
6198     MaybeParseCXX11Attributes(attrs);
6199 
6200     // Remember that we parsed a array type, and remember its features.
6201     D.AddTypeInfo(DeclaratorChunk::getArray(0, false, false,
6202                                             ExprRes.get(),
6203                                             T.getOpenLocation(),
6204                                             T.getCloseLocation()),
6205                   attrs, T.getCloseLocation());
6206     return;
6207   } else if (Tok.getKind() == tok::code_completion) {
6208     Actions.CodeCompleteBracketDeclarator(getCurScope());
6209     return cutOffParsing();
6210   }
6211 
6212   // If valid, this location is the position where we read the 'static' keyword.
6213   SourceLocation StaticLoc;
6214   TryConsumeToken(tok::kw_static, StaticLoc);
6215 
6216   // If there is a type-qualifier-list, read it now.
6217   // Type qualifiers in an array subscript are a C99 feature.
6218   DeclSpec DS(AttrFactory);
6219   ParseTypeQualifierListOpt(DS, AR_CXX11AttributesParsed);
6220 
6221   // If we haven't already read 'static', check to see if there is one after the
6222   // type-qualifier-list.
6223   if (!StaticLoc.isValid())
6224     TryConsumeToken(tok::kw_static, StaticLoc);
6225 
6226   // Handle "direct-declarator [ type-qual-list[opt] * ]".
6227   bool isStar = false;
6228   ExprResult NumElements;
6229 
6230   // Handle the case where we have '[*]' as the array size.  However, a leading
6231   // star could be the start of an expression, for example 'X[*p + 4]'.  Verify
6232   // the token after the star is a ']'.  Since stars in arrays are
6233   // infrequent, use of lookahead is not costly here.
6234   if (Tok.is(tok::star) && GetLookAheadToken(1).is(tok::r_square)) {
6235     ConsumeToken();  // Eat the '*'.
6236 
6237     if (StaticLoc.isValid()) {
6238       Diag(StaticLoc, diag::err_unspecified_vla_size_with_static);
6239       StaticLoc = SourceLocation();  // Drop the static.
6240     }
6241     isStar = true;
6242   } else if (Tok.isNot(tok::r_square)) {
6243     // Note, in C89, this production uses the constant-expr production instead
6244     // of assignment-expr.  The only difference is that assignment-expr allows
6245     // things like '=' and '*='.  Sema rejects these in C89 mode because they
6246     // are not i-c-e's, so we don't need to distinguish between the two here.
6247 
6248     // Parse the constant-expression or assignment-expression now (depending
6249     // on dialect).
6250     if (getLangOpts().CPlusPlus) {
6251       NumElements = ParseConstantExpression();
6252     } else {
6253       EnterExpressionEvaluationContext Unevaluated(Actions,
6254                                                    Sema::ConstantEvaluated);
6255       NumElements =
6256           Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression());
6257     }
6258   } else {
6259     if (StaticLoc.isValid()) {
6260       Diag(StaticLoc, diag::err_unspecified_size_with_static);
6261       StaticLoc = SourceLocation();  // Drop the static.
6262     }
6263   }
6264 
6265   // If there was an error parsing the assignment-expression, recover.
6266   if (NumElements.isInvalid()) {
6267     D.setInvalidType(true);
6268     // If the expression was invalid, skip it.
6269     SkipUntil(tok::r_square, StopAtSemi);
6270     return;
6271   }
6272 
6273   T.consumeClose();
6274 
6275   MaybeParseCXX11Attributes(DS.getAttributes());
6276 
6277   // Remember that we parsed a array type, and remember its features.
6278   D.AddTypeInfo(DeclaratorChunk::getArray(DS.getTypeQualifiers(),
6279                                           StaticLoc.isValid(), isStar,
6280                                           NumElements.get(),
6281                                           T.getOpenLocation(),
6282                                           T.getCloseLocation()),
6283                 DS.getAttributes(), T.getCloseLocation());
6284 }
6285 
6286 /// Diagnose brackets before an identifier.
6287 void Parser::ParseMisplacedBracketDeclarator(Declarator &D) {
6288   assert(Tok.is(tok::l_square) && "Missing opening bracket");
6289   assert(!D.mayOmitIdentifier() && "Declarator cannot omit identifier");
6290 
6291   SourceLocation StartBracketLoc = Tok.getLocation();
6292   Declarator TempDeclarator(D.getDeclSpec(), D.getContext());
6293 
6294   while (Tok.is(tok::l_square)) {
6295     ParseBracketDeclarator(TempDeclarator);
6296   }
6297 
6298   // Stuff the location of the start of the brackets into the Declarator.
6299   // The diagnostics from ParseDirectDeclarator will make more sense if
6300   // they use this location instead.
6301   if (Tok.is(tok::semi))
6302     D.getName().EndLocation = StartBracketLoc;
6303 
6304   SourceLocation SuggestParenLoc = Tok.getLocation();
6305 
6306   // Now that the brackets are removed, try parsing the declarator again.
6307   ParseDeclaratorInternal(D, &Parser::ParseDirectDeclarator);
6308 
6309   // Something went wrong parsing the brackets, in which case,
6310   // ParseBracketDeclarator has emitted an error, and we don't need to emit
6311   // one here.
6312   if (TempDeclarator.getNumTypeObjects() == 0)
6313     return;
6314 
6315   // Determine if parens will need to be suggested in the diagnostic.
6316   bool NeedParens = false;
6317   if (D.getNumTypeObjects() != 0) {
6318     switch (D.getTypeObject(D.getNumTypeObjects() - 1).Kind) {
6319     case DeclaratorChunk::Pointer:
6320     case DeclaratorChunk::Reference:
6321     case DeclaratorChunk::BlockPointer:
6322     case DeclaratorChunk::MemberPointer:
6323     case DeclaratorChunk::Pipe:
6324       NeedParens = true;
6325       break;
6326     case DeclaratorChunk::Array:
6327     case DeclaratorChunk::Function:
6328     case DeclaratorChunk::Paren:
6329       break;
6330     }
6331   }
6332 
6333   if (NeedParens) {
6334     // Create a DeclaratorChunk for the inserted parens.
6335     ParsedAttributes attrs(AttrFactory);
6336     SourceLocation EndLoc = PP.getLocForEndOfToken(D.getLocEnd());
6337     D.AddTypeInfo(DeclaratorChunk::getParen(SuggestParenLoc, EndLoc), attrs,
6338                   SourceLocation());
6339   }
6340 
6341   // Adding back the bracket info to the end of the Declarator.
6342   for (unsigned i = 0, e = TempDeclarator.getNumTypeObjects(); i < e; ++i) {
6343     const DeclaratorChunk &Chunk = TempDeclarator.getTypeObject(i);
6344     ParsedAttributes attrs(AttrFactory);
6345     attrs.set(Chunk.Common.AttrList);
6346     D.AddTypeInfo(Chunk, attrs, SourceLocation());
6347   }
6348 
6349   // The missing identifier would have been diagnosed in ParseDirectDeclarator.
6350   // If parentheses are required, always suggest them.
6351   if (!D.getIdentifier() && !NeedParens)
6352     return;
6353 
6354   SourceLocation EndBracketLoc = TempDeclarator.getLocEnd();
6355 
6356   // Generate the move bracket error message.
6357   SourceRange BracketRange(StartBracketLoc, EndBracketLoc);
6358   SourceLocation EndLoc = PP.getLocForEndOfToken(D.getLocEnd());
6359 
6360   if (NeedParens) {
6361     Diag(EndLoc, diag::err_brackets_go_after_unqualified_id)
6362         << getLangOpts().CPlusPlus
6363         << FixItHint::CreateInsertion(SuggestParenLoc, "(")
6364         << FixItHint::CreateInsertion(EndLoc, ")")
6365         << FixItHint::CreateInsertionFromRange(
6366                EndLoc, CharSourceRange(BracketRange, true))
6367         << FixItHint::CreateRemoval(BracketRange);
6368   } else {
6369     Diag(EndLoc, diag::err_brackets_go_after_unqualified_id)
6370         << getLangOpts().CPlusPlus
6371         << FixItHint::CreateInsertionFromRange(
6372                EndLoc, CharSourceRange(BracketRange, true))
6373         << FixItHint::CreateRemoval(BracketRange);
6374   }
6375 }
6376 
6377 /// [GNU]   typeof-specifier:
6378 ///           typeof ( expressions )
6379 ///           typeof ( type-name )
6380 /// [GNU/C++] typeof unary-expression
6381 ///
6382 void Parser::ParseTypeofSpecifier(DeclSpec &DS) {
6383   assert(Tok.is(tok::kw_typeof) && "Not a typeof specifier");
6384   Token OpTok = Tok;
6385   SourceLocation StartLoc = ConsumeToken();
6386 
6387   const bool hasParens = Tok.is(tok::l_paren);
6388 
6389   EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated,
6390                                                Sema::ReuseLambdaContextDecl);
6391 
6392   bool isCastExpr;
6393   ParsedType CastTy;
6394   SourceRange CastRange;
6395   ExprResult Operand = Actions.CorrectDelayedTyposInExpr(
6396       ParseExprAfterUnaryExprOrTypeTrait(OpTok, isCastExpr, CastTy, CastRange));
6397   if (hasParens)
6398     DS.setTypeofParensRange(CastRange);
6399 
6400   if (CastRange.getEnd().isInvalid())
6401     // FIXME: Not accurate, the range gets one token more than it should.
6402     DS.SetRangeEnd(Tok.getLocation());
6403   else
6404     DS.SetRangeEnd(CastRange.getEnd());
6405 
6406   if (isCastExpr) {
6407     if (!CastTy) {
6408       DS.SetTypeSpecError();
6409       return;
6410     }
6411 
6412     const char *PrevSpec = nullptr;
6413     unsigned DiagID;
6414     // Check for duplicate type specifiers (e.g. "int typeof(int)").
6415     if (DS.SetTypeSpecType(DeclSpec::TST_typeofType, StartLoc, PrevSpec,
6416                            DiagID, CastTy,
6417                            Actions.getASTContext().getPrintingPolicy()))
6418       Diag(StartLoc, DiagID) << PrevSpec;
6419     return;
6420   }
6421 
6422   // If we get here, the operand to the typeof was an expresion.
6423   if (Operand.isInvalid()) {
6424     DS.SetTypeSpecError();
6425     return;
6426   }
6427 
6428   // We might need to transform the operand if it is potentially evaluated.
6429   Operand = Actions.HandleExprEvaluationContextForTypeof(Operand.get());
6430   if (Operand.isInvalid()) {
6431     DS.SetTypeSpecError();
6432     return;
6433   }
6434 
6435   const char *PrevSpec = nullptr;
6436   unsigned DiagID;
6437   // Check for duplicate type specifiers (e.g. "int typeof(int)").
6438   if (DS.SetTypeSpecType(DeclSpec::TST_typeofExpr, StartLoc, PrevSpec,
6439                          DiagID, Operand.get(),
6440                          Actions.getASTContext().getPrintingPolicy()))
6441     Diag(StartLoc, DiagID) << PrevSpec;
6442 }
6443 
6444 /// [C11]   atomic-specifier:
6445 ///           _Atomic ( type-name )
6446 ///
6447 void Parser::ParseAtomicSpecifier(DeclSpec &DS) {
6448   assert(Tok.is(tok::kw__Atomic) && NextToken().is(tok::l_paren) &&
6449          "Not an atomic specifier");
6450 
6451   SourceLocation StartLoc = ConsumeToken();
6452   BalancedDelimiterTracker T(*this, tok::l_paren);
6453   if (T.consumeOpen())
6454     return;
6455 
6456   TypeResult Result = ParseTypeName();
6457   if (Result.isInvalid()) {
6458     SkipUntil(tok::r_paren, StopAtSemi);
6459     return;
6460   }
6461 
6462   // Match the ')'
6463   T.consumeClose();
6464 
6465   if (T.getCloseLocation().isInvalid())
6466     return;
6467 
6468   DS.setTypeofParensRange(T.getRange());
6469   DS.SetRangeEnd(T.getCloseLocation());
6470 
6471   const char *PrevSpec = nullptr;
6472   unsigned DiagID;
6473   if (DS.SetTypeSpecType(DeclSpec::TST_atomic, StartLoc, PrevSpec,
6474                          DiagID, Result.get(),
6475                          Actions.getASTContext().getPrintingPolicy()))
6476     Diag(StartLoc, DiagID) << PrevSpec;
6477 }
6478 
6479 /// TryAltiVecVectorTokenOutOfLine - Out of line body that should only be called
6480 /// from TryAltiVecVectorToken.
6481 bool Parser::TryAltiVecVectorTokenOutOfLine() {
6482   Token Next = NextToken();
6483   switch (Next.getKind()) {
6484   default: return false;
6485   case tok::kw_short:
6486   case tok::kw_long:
6487   case tok::kw_signed:
6488   case tok::kw_unsigned:
6489   case tok::kw_void:
6490   case tok::kw_char:
6491   case tok::kw_int:
6492   case tok::kw_float:
6493   case tok::kw_double:
6494   case tok::kw_bool:
6495   case tok::kw___bool:
6496   case tok::kw___pixel:
6497     Tok.setKind(tok::kw___vector);
6498     return true;
6499   case tok::identifier:
6500     if (Next.getIdentifierInfo() == Ident_pixel) {
6501       Tok.setKind(tok::kw___vector);
6502       return true;
6503     }
6504     if (Next.getIdentifierInfo() == Ident_bool) {
6505       Tok.setKind(tok::kw___vector);
6506       return true;
6507     }
6508     return false;
6509   }
6510 }
6511 
6512 bool Parser::TryAltiVecTokenOutOfLine(DeclSpec &DS, SourceLocation Loc,
6513                                       const char *&PrevSpec, unsigned &DiagID,
6514                                       bool &isInvalid) {
6515   const PrintingPolicy &Policy = Actions.getASTContext().getPrintingPolicy();
6516   if (Tok.getIdentifierInfo() == Ident_vector) {
6517     Token Next = NextToken();
6518     switch (Next.getKind()) {
6519     case tok::kw_short:
6520     case tok::kw_long:
6521     case tok::kw_signed:
6522     case tok::kw_unsigned:
6523     case tok::kw_void:
6524     case tok::kw_char:
6525     case tok::kw_int:
6526     case tok::kw_float:
6527     case tok::kw_double:
6528     case tok::kw_bool:
6529     case tok::kw___bool:
6530     case tok::kw___pixel:
6531       isInvalid = DS.SetTypeAltiVecVector(true, Loc, PrevSpec, DiagID, Policy);
6532       return true;
6533     case tok::identifier:
6534       if (Next.getIdentifierInfo() == Ident_pixel) {
6535         isInvalid = DS.SetTypeAltiVecVector(true, Loc, PrevSpec, DiagID,Policy);
6536         return true;
6537       }
6538       if (Next.getIdentifierInfo() == Ident_bool) {
6539         isInvalid = DS.SetTypeAltiVecVector(true, Loc, PrevSpec, DiagID,Policy);
6540         return true;
6541       }
6542       break;
6543     default:
6544       break;
6545     }
6546   } else if ((Tok.getIdentifierInfo() == Ident_pixel) &&
6547              DS.isTypeAltiVecVector()) {
6548     isInvalid = DS.SetTypeAltiVecPixel(true, Loc, PrevSpec, DiagID, Policy);
6549     return true;
6550   } else if ((Tok.getIdentifierInfo() == Ident_bool) &&
6551              DS.isTypeAltiVecVector()) {
6552     isInvalid = DS.SetTypeAltiVecBool(true, Loc, PrevSpec, DiagID, Policy);
6553     return true;
6554   }
6555   return false;
6556 }
6557