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      1 //===--- ParseCXXInlineMethods.cpp - C++ class inline methods parsing------===//
      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 parsing for C++ class inline methods.
     11 //
     12 //===----------------------------------------------------------------------===//
     13 
     14 #include "clang/Parse/Parser.h"
     15 #include "RAIIObjectsForParser.h"
     16 #include "clang/AST/DeclTemplate.h"
     17 #include "clang/Parse/ParseDiagnostic.h"
     18 #include "clang/Sema/DeclSpec.h"
     19 #include "clang/Sema/Scope.h"
     20 using namespace clang;
     21 
     22 /// ParseCXXInlineMethodDef - We parsed and verified that the specified
     23 /// Declarator is a well formed C++ inline method definition. Now lex its body
     24 /// and store its tokens for parsing after the C++ class is complete.
     25 NamedDecl *Parser::ParseCXXInlineMethodDef(AccessSpecifier AS,
     26                                       AttributeList *AccessAttrs,
     27                                       ParsingDeclarator &D,
     28                                       const ParsedTemplateInfo &TemplateInfo,
     29                                       const VirtSpecifiers& VS,
     30                                       SourceLocation PureSpecLoc) {
     31   assert(D.isFunctionDeclarator() && "This isn't a function declarator!");
     32   assert(Tok.isOneOf(tok::l_brace, tok::colon, tok::kw_try, tok::equal) &&
     33          "Current token not a '{', ':', '=', or 'try'!");
     34 
     35   MultiTemplateParamsArg TemplateParams(
     36       TemplateInfo.TemplateParams ? TemplateInfo.TemplateParams->data()
     37                                   : nullptr,
     38       TemplateInfo.TemplateParams ? TemplateInfo.TemplateParams->size() : 0);
     39 
     40   NamedDecl *FnD;
     41   if (D.getDeclSpec().isFriendSpecified())
     42     FnD = Actions.ActOnFriendFunctionDecl(getCurScope(), D,
     43                                           TemplateParams);
     44   else {
     45     FnD = Actions.ActOnCXXMemberDeclarator(getCurScope(), AS, D,
     46                                            TemplateParams, nullptr,
     47                                            VS, ICIS_NoInit);
     48     if (FnD) {
     49       Actions.ProcessDeclAttributeList(getCurScope(), FnD, AccessAttrs);
     50       if (PureSpecLoc.isValid())
     51         Actions.ActOnPureSpecifier(FnD, PureSpecLoc);
     52     }
     53   }
     54 
     55   if (FnD)
     56     HandleMemberFunctionDeclDelays(D, FnD);
     57 
     58   D.complete(FnD);
     59 
     60   if (TryConsumeToken(tok::equal)) {
     61     if (!FnD) {
     62       SkipUntil(tok::semi);
     63       return nullptr;
     64     }
     65 
     66     bool Delete = false;
     67     SourceLocation KWLoc;
     68     SourceLocation KWEndLoc = Tok.getEndLoc().getLocWithOffset(-1);
     69     if (TryConsumeToken(tok::kw_delete, KWLoc)) {
     70       Diag(KWLoc, getLangOpts().CPlusPlus11
     71                       ? diag::warn_cxx98_compat_defaulted_deleted_function
     72                       : diag::ext_defaulted_deleted_function)
     73         << 1 /* deleted */;
     74       Actions.SetDeclDeleted(FnD, KWLoc);
     75       Delete = true;
     76       if (auto *DeclAsFunction = dyn_cast<FunctionDecl>(FnD)) {
     77         DeclAsFunction->setRangeEnd(KWEndLoc);
     78       }
     79     } else if (TryConsumeToken(tok::kw_default, KWLoc)) {
     80       Diag(KWLoc, getLangOpts().CPlusPlus11
     81                       ? diag::warn_cxx98_compat_defaulted_deleted_function
     82                       : diag::ext_defaulted_deleted_function)
     83         << 0 /* defaulted */;
     84       Actions.SetDeclDefaulted(FnD, KWLoc);
     85       if (auto *DeclAsFunction = dyn_cast<FunctionDecl>(FnD)) {
     86         DeclAsFunction->setRangeEnd(KWEndLoc);
     87       }
     88     } else {
     89       llvm_unreachable("function definition after = not 'delete' or 'default'");
     90     }
     91 
     92     if (Tok.is(tok::comma)) {
     93       Diag(KWLoc, diag::err_default_delete_in_multiple_declaration)
     94         << Delete;
     95       SkipUntil(tok::semi);
     96     } else if (ExpectAndConsume(tok::semi, diag::err_expected_after,
     97                                 Delete ? "delete" : "default")) {
     98       SkipUntil(tok::semi);
     99     }
    100 
    101     return FnD;
    102   }
    103 
    104   if (SkipFunctionBodies && (!FnD || Actions.canSkipFunctionBody(FnD)) &&
    105       trySkippingFunctionBody()) {
    106     Actions.ActOnSkippedFunctionBody(FnD);
    107     return FnD;
    108   }
    109 
    110   // In delayed template parsing mode, if we are within a class template
    111   // or if we are about to parse function member template then consume
    112   // the tokens and store them for parsing at the end of the translation unit.
    113   if (getLangOpts().DelayedTemplateParsing &&
    114       D.getFunctionDefinitionKind() == FDK_Definition &&
    115       !D.getDeclSpec().isConstexprSpecified() &&
    116       !(FnD && FnD->getAsFunction() &&
    117         FnD->getAsFunction()->getReturnType()->getContainedAutoType()) &&
    118       ((Actions.CurContext->isDependentContext() ||
    119         (TemplateInfo.Kind != ParsedTemplateInfo::NonTemplate &&
    120          TemplateInfo.Kind != ParsedTemplateInfo::ExplicitSpecialization)) &&
    121        !Actions.IsInsideALocalClassWithinATemplateFunction())) {
    122 
    123     CachedTokens Toks;
    124     LexTemplateFunctionForLateParsing(Toks);
    125 
    126     if (FnD) {
    127       FunctionDecl *FD = FnD->getAsFunction();
    128       Actions.CheckForFunctionRedefinition(FD);
    129       Actions.MarkAsLateParsedTemplate(FD, FnD, Toks);
    130     }
    131 
    132     return FnD;
    133   }
    134 
    135   // Consume the tokens and store them for later parsing.
    136 
    137   LexedMethod* LM = new LexedMethod(this, FnD);
    138   getCurrentClass().LateParsedDeclarations.push_back(LM);
    139   LM->TemplateScope = getCurScope()->isTemplateParamScope();
    140   CachedTokens &Toks = LM->Toks;
    141 
    142   tok::TokenKind kind = Tok.getKind();
    143   // Consume everything up to (and including) the left brace of the
    144   // function body.
    145   if (ConsumeAndStoreFunctionPrologue(Toks)) {
    146     // We didn't find the left-brace we expected after the
    147     // constructor initializer; we already printed an error, and it's likely
    148     // impossible to recover, so don't try to parse this method later.
    149     // Skip over the rest of the decl and back to somewhere that looks
    150     // reasonable.
    151     SkipMalformedDecl();
    152     delete getCurrentClass().LateParsedDeclarations.back();
    153     getCurrentClass().LateParsedDeclarations.pop_back();
    154     return FnD;
    155   } else {
    156     // Consume everything up to (and including) the matching right brace.
    157     ConsumeAndStoreUntil(tok::r_brace, Toks, /*StopAtSemi=*/false);
    158   }
    159 
    160   // If we're in a function-try-block, we need to store all the catch blocks.
    161   if (kind == tok::kw_try) {
    162     while (Tok.is(tok::kw_catch)) {
    163       ConsumeAndStoreUntil(tok::l_brace, Toks, /*StopAtSemi=*/false);
    164       ConsumeAndStoreUntil(tok::r_brace, Toks, /*StopAtSemi=*/false);
    165     }
    166   }
    167 
    168   if (FnD) {
    169     // If this is a friend function, mark that it's late-parsed so that
    170     // it's still known to be a definition even before we attach the
    171     // parsed body.  Sema needs to treat friend function definitions
    172     // differently during template instantiation, and it's possible for
    173     // the containing class to be instantiated before all its member
    174     // function definitions are parsed.
    175     //
    176     // If you remove this, you can remove the code that clears the flag
    177     // after parsing the member.
    178     if (D.getDeclSpec().isFriendSpecified()) {
    179       FunctionDecl *FD = FnD->getAsFunction();
    180       Actions.CheckForFunctionRedefinition(FD);
    181       FD->setLateTemplateParsed(true);
    182     }
    183   } else {
    184     // If semantic analysis could not build a function declaration,
    185     // just throw away the late-parsed declaration.
    186     delete getCurrentClass().LateParsedDeclarations.back();
    187     getCurrentClass().LateParsedDeclarations.pop_back();
    188   }
    189 
    190   return FnD;
    191 }
    192 
    193 /// ParseCXXNonStaticMemberInitializer - We parsed and verified that the
    194 /// specified Declarator is a well formed C++ non-static data member
    195 /// declaration. Now lex its initializer and store its tokens for parsing
    196 /// after the class is complete.
    197 void Parser::ParseCXXNonStaticMemberInitializer(Decl *VarD) {
    198   assert(Tok.isOneOf(tok::l_brace, tok::equal) &&
    199          "Current token not a '{' or '='!");
    200 
    201   LateParsedMemberInitializer *MI =
    202     new LateParsedMemberInitializer(this, VarD);
    203   getCurrentClass().LateParsedDeclarations.push_back(MI);
    204   CachedTokens &Toks = MI->Toks;
    205 
    206   tok::TokenKind kind = Tok.getKind();
    207   if (kind == tok::equal) {
    208     Toks.push_back(Tok);
    209     ConsumeToken();
    210   }
    211 
    212   if (kind == tok::l_brace) {
    213     // Begin by storing the '{' token.
    214     Toks.push_back(Tok);
    215     ConsumeBrace();
    216 
    217     // Consume everything up to (and including) the matching right brace.
    218     ConsumeAndStoreUntil(tok::r_brace, Toks, /*StopAtSemi=*/true);
    219   } else {
    220     // Consume everything up to (but excluding) the comma or semicolon.
    221     ConsumeAndStoreInitializer(Toks, CIK_DefaultInitializer);
    222   }
    223 
    224   // Store an artificial EOF token to ensure that we don't run off the end of
    225   // the initializer when we come to parse it.
    226   Token Eof;
    227   Eof.startToken();
    228   Eof.setKind(tok::eof);
    229   Eof.setLocation(Tok.getLocation());
    230   Eof.setEofData(VarD);
    231   Toks.push_back(Eof);
    232 }
    233 
    234 Parser::LateParsedDeclaration::~LateParsedDeclaration() {}
    235 void Parser::LateParsedDeclaration::ParseLexedMethodDeclarations() {}
    236 void Parser::LateParsedDeclaration::ParseLexedMemberInitializers() {}
    237 void Parser::LateParsedDeclaration::ParseLexedMethodDefs() {}
    238 
    239 Parser::LateParsedClass::LateParsedClass(Parser *P, ParsingClass *C)
    240   : Self(P), Class(C) {}
    241 
    242 Parser::LateParsedClass::~LateParsedClass() {
    243   Self->DeallocateParsedClasses(Class);
    244 }
    245 
    246 void Parser::LateParsedClass::ParseLexedMethodDeclarations() {
    247   Self->ParseLexedMethodDeclarations(*Class);
    248 }
    249 
    250 void Parser::LateParsedClass::ParseLexedMemberInitializers() {
    251   Self->ParseLexedMemberInitializers(*Class);
    252 }
    253 
    254 void Parser::LateParsedClass::ParseLexedMethodDefs() {
    255   Self->ParseLexedMethodDefs(*Class);
    256 }
    257 
    258 void Parser::LateParsedMethodDeclaration::ParseLexedMethodDeclarations() {
    259   Self->ParseLexedMethodDeclaration(*this);
    260 }
    261 
    262 void Parser::LexedMethod::ParseLexedMethodDefs() {
    263   Self->ParseLexedMethodDef(*this);
    264 }
    265 
    266 void Parser::LateParsedMemberInitializer::ParseLexedMemberInitializers() {
    267   Self->ParseLexedMemberInitializer(*this);
    268 }
    269 
    270 /// ParseLexedMethodDeclarations - We finished parsing the member
    271 /// specification of a top (non-nested) C++ class. Now go over the
    272 /// stack of method declarations with some parts for which parsing was
    273 /// delayed (such as default arguments) and parse them.
    274 void Parser::ParseLexedMethodDeclarations(ParsingClass &Class) {
    275   bool HasTemplateScope = !Class.TopLevelClass && Class.TemplateScope;
    276   ParseScope ClassTemplateScope(this, Scope::TemplateParamScope,
    277                                 HasTemplateScope);
    278   TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
    279   if (HasTemplateScope) {
    280     Actions.ActOnReenterTemplateScope(getCurScope(), Class.TagOrTemplate);
    281     ++CurTemplateDepthTracker;
    282   }
    283 
    284   // The current scope is still active if we're the top-level class.
    285   // Otherwise we'll need to push and enter a new scope.
    286   bool HasClassScope = !Class.TopLevelClass;
    287   ParseScope ClassScope(this, Scope::ClassScope|Scope::DeclScope,
    288                         HasClassScope);
    289   if (HasClassScope)
    290     Actions.ActOnStartDelayedMemberDeclarations(getCurScope(),
    291                                                 Class.TagOrTemplate);
    292 
    293   for (size_t i = 0; i < Class.LateParsedDeclarations.size(); ++i) {
    294     Class.LateParsedDeclarations[i]->ParseLexedMethodDeclarations();
    295   }
    296 
    297   if (HasClassScope)
    298     Actions.ActOnFinishDelayedMemberDeclarations(getCurScope(),
    299                                                  Class.TagOrTemplate);
    300 }
    301 
    302 void Parser::ParseLexedMethodDeclaration(LateParsedMethodDeclaration &LM) {
    303   // If this is a member template, introduce the template parameter scope.
    304   ParseScope TemplateScope(this, Scope::TemplateParamScope, LM.TemplateScope);
    305   TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
    306   if (LM.TemplateScope) {
    307     Actions.ActOnReenterTemplateScope(getCurScope(), LM.Method);
    308     ++CurTemplateDepthTracker;
    309   }
    310   // Start the delayed C++ method declaration
    311   Actions.ActOnStartDelayedCXXMethodDeclaration(getCurScope(), LM.Method);
    312 
    313   // Introduce the parameters into scope and parse their default
    314   // arguments.
    315   ParseScope PrototypeScope(this, Scope::FunctionPrototypeScope |
    316                             Scope::FunctionDeclarationScope | Scope::DeclScope);
    317   for (unsigned I = 0, N = LM.DefaultArgs.size(); I != N; ++I) {
    318     auto Param = cast<ParmVarDecl>(LM.DefaultArgs[I].Param);
    319     // Introduce the parameter into scope.
    320     bool HasUnparsed = Param->hasUnparsedDefaultArg();
    321     Actions.ActOnDelayedCXXMethodParameter(getCurScope(), Param);
    322     if (CachedTokens *Toks = LM.DefaultArgs[I].Toks) {
    323       // Mark the end of the default argument so that we know when to stop when
    324       // we parse it later on.
    325       Token LastDefaultArgToken = Toks->back();
    326       Token DefArgEnd;
    327       DefArgEnd.startToken();
    328       DefArgEnd.setKind(tok::eof);
    329       DefArgEnd.setLocation(LastDefaultArgToken.getEndLoc());
    330       DefArgEnd.setEofData(Param);
    331       Toks->push_back(DefArgEnd);
    332 
    333       // Parse the default argument from its saved token stream.
    334       Toks->push_back(Tok); // So that the current token doesn't get lost
    335       PP.EnterTokenStream(*Toks, true);
    336 
    337       // Consume the previously-pushed token.
    338       ConsumeAnyToken();
    339 
    340       // Consume the '='.
    341       assert(Tok.is(tok::equal) && "Default argument not starting with '='");
    342       SourceLocation EqualLoc = ConsumeToken();
    343 
    344       // The argument isn't actually potentially evaluated unless it is
    345       // used.
    346       EnterExpressionEvaluationContext Eval(Actions,
    347                                             Sema::PotentiallyEvaluatedIfUsed,
    348                                             Param);
    349 
    350       ExprResult DefArgResult;
    351       if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) {
    352         Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists);
    353         DefArgResult = ParseBraceInitializer();
    354       } else
    355         DefArgResult = ParseAssignmentExpression();
    356       DefArgResult = Actions.CorrectDelayedTyposInExpr(DefArgResult);
    357       if (DefArgResult.isInvalid()) {
    358         Actions.ActOnParamDefaultArgumentError(Param, EqualLoc);
    359       } else {
    360         if (Tok.isNot(tok::eof) || Tok.getEofData() != Param) {
    361           // The last two tokens are the terminator and the saved value of
    362           // Tok; the last token in the default argument is the one before
    363           // those.
    364           assert(Toks->size() >= 3 && "expected a token in default arg");
    365           Diag(Tok.getLocation(), diag::err_default_arg_unparsed)
    366             << SourceRange(Tok.getLocation(),
    367                            (*Toks)[Toks->size() - 3].getLocation());
    368         }
    369         Actions.ActOnParamDefaultArgument(Param, EqualLoc,
    370                                           DefArgResult.get());
    371       }
    372 
    373       // There could be leftover tokens (e.g. because of an error).
    374       // Skip through until we reach the 'end of default argument' token.
    375       while (Tok.isNot(tok::eof))
    376         ConsumeAnyToken();
    377 
    378       if (Tok.is(tok::eof) && Tok.getEofData() == Param)
    379         ConsumeAnyToken();
    380 
    381       delete Toks;
    382       LM.DefaultArgs[I].Toks = nullptr;
    383     } else if (HasUnparsed) {
    384       assert(Param->hasInheritedDefaultArg());
    385       FunctionDecl *Old = cast<FunctionDecl>(LM.Method)->getPreviousDecl();
    386       ParmVarDecl *OldParam = Old->getParamDecl(I);
    387       assert (!OldParam->hasUnparsedDefaultArg());
    388       if (OldParam->hasUninstantiatedDefaultArg())
    389         Param->setUninstantiatedDefaultArg(
    390             OldParam->getUninstantiatedDefaultArg());
    391       else
    392         Param->setDefaultArg(OldParam->getInit());
    393     }
    394   }
    395 
    396   // Parse a delayed exception-specification, if there is one.
    397   if (CachedTokens *Toks = LM.ExceptionSpecTokens) {
    398     // Add the 'stop' token.
    399     Token LastExceptionSpecToken = Toks->back();
    400     Token ExceptionSpecEnd;
    401     ExceptionSpecEnd.startToken();
    402     ExceptionSpecEnd.setKind(tok::eof);
    403     ExceptionSpecEnd.setLocation(LastExceptionSpecToken.getEndLoc());
    404     ExceptionSpecEnd.setEofData(LM.Method);
    405     Toks->push_back(ExceptionSpecEnd);
    406 
    407     // Parse the default argument from its saved token stream.
    408     Toks->push_back(Tok); // So that the current token doesn't get lost
    409     PP.EnterTokenStream(*Toks, true);
    410 
    411     // Consume the previously-pushed token.
    412     ConsumeAnyToken();
    413 
    414     // C++11 [expr.prim.general]p3:
    415     //   If a declaration declares a member function or member function
    416     //   template of a class X, the expression this is a prvalue of type
    417     //   "pointer to cv-qualifier-seq X" between the optional cv-qualifer-seq
    418     //   and the end of the function-definition, member-declarator, or
    419     //   declarator.
    420     CXXMethodDecl *Method;
    421     if (FunctionTemplateDecl *FunTmpl
    422           = dyn_cast<FunctionTemplateDecl>(LM.Method))
    423       Method = cast<CXXMethodDecl>(FunTmpl->getTemplatedDecl());
    424     else
    425       Method = cast<CXXMethodDecl>(LM.Method);
    426 
    427     Sema::CXXThisScopeRAII ThisScope(Actions, Method->getParent(),
    428                                      Method->getTypeQualifiers(),
    429                                      getLangOpts().CPlusPlus11);
    430 
    431     // Parse the exception-specification.
    432     SourceRange SpecificationRange;
    433     SmallVector<ParsedType, 4> DynamicExceptions;
    434     SmallVector<SourceRange, 4> DynamicExceptionRanges;
    435     ExprResult NoexceptExpr;
    436     CachedTokens *ExceptionSpecTokens;
    437 
    438     ExceptionSpecificationType EST
    439       = tryParseExceptionSpecification(/*Delayed=*/false, SpecificationRange,
    440                                        DynamicExceptions,
    441                                        DynamicExceptionRanges, NoexceptExpr,
    442                                        ExceptionSpecTokens);
    443 
    444     if (Tok.isNot(tok::eof) || Tok.getEofData() != LM.Method)
    445       Diag(Tok.getLocation(), diag::err_except_spec_unparsed);
    446 
    447     // Attach the exception-specification to the method.
    448     Actions.actOnDelayedExceptionSpecification(LM.Method, EST,
    449                                                SpecificationRange,
    450                                                DynamicExceptions,
    451                                                DynamicExceptionRanges,
    452                                                NoexceptExpr.isUsable()?
    453                                                  NoexceptExpr.get() : nullptr);
    454 
    455     // There could be leftover tokens (e.g. because of an error).
    456     // Skip through until we reach the original token position.
    457     while (Tok.isNot(tok::eof))
    458       ConsumeAnyToken();
    459 
    460     // Clean up the remaining EOF token.
    461     if (Tok.is(tok::eof) && Tok.getEofData() == LM.Method)
    462       ConsumeAnyToken();
    463 
    464     delete Toks;
    465     LM.ExceptionSpecTokens = nullptr;
    466   }
    467 
    468   PrototypeScope.Exit();
    469 
    470   // Finish the delayed C++ method declaration.
    471   Actions.ActOnFinishDelayedCXXMethodDeclaration(getCurScope(), LM.Method);
    472 }
    473 
    474 /// ParseLexedMethodDefs - We finished parsing the member specification of a top
    475 /// (non-nested) C++ class. Now go over the stack of lexed methods that were
    476 /// collected during its parsing and parse them all.
    477 void Parser::ParseLexedMethodDefs(ParsingClass &Class) {
    478   bool HasTemplateScope = !Class.TopLevelClass && Class.TemplateScope;
    479   ParseScope ClassTemplateScope(this, Scope::TemplateParamScope, HasTemplateScope);
    480   TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
    481   if (HasTemplateScope) {
    482     Actions.ActOnReenterTemplateScope(getCurScope(), Class.TagOrTemplate);
    483     ++CurTemplateDepthTracker;
    484   }
    485   bool HasClassScope = !Class.TopLevelClass;
    486   ParseScope ClassScope(this, Scope::ClassScope|Scope::DeclScope,
    487                         HasClassScope);
    488 
    489   for (size_t i = 0; i < Class.LateParsedDeclarations.size(); ++i) {
    490     Class.LateParsedDeclarations[i]->ParseLexedMethodDefs();
    491   }
    492 }
    493 
    494 void Parser::ParseLexedMethodDef(LexedMethod &LM) {
    495   // If this is a member template, introduce the template parameter scope.
    496   ParseScope TemplateScope(this, Scope::TemplateParamScope, LM.TemplateScope);
    497   TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
    498   if (LM.TemplateScope) {
    499     Actions.ActOnReenterTemplateScope(getCurScope(), LM.D);
    500     ++CurTemplateDepthTracker;
    501   }
    502 
    503   assert(!LM.Toks.empty() && "Empty body!");
    504   Token LastBodyToken = LM.Toks.back();
    505   Token BodyEnd;
    506   BodyEnd.startToken();
    507   BodyEnd.setKind(tok::eof);
    508   BodyEnd.setLocation(LastBodyToken.getEndLoc());
    509   BodyEnd.setEofData(LM.D);
    510   LM.Toks.push_back(BodyEnd);
    511   // Append the current token at the end of the new token stream so that it
    512   // doesn't get lost.
    513   LM.Toks.push_back(Tok);
    514   PP.EnterTokenStream(LM.Toks, true);
    515 
    516   // Consume the previously pushed token.
    517   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
    518   assert(Tok.isOneOf(tok::l_brace, tok::colon, tok::kw_try)
    519          && "Inline method not starting with '{', ':' or 'try'");
    520 
    521   // Parse the method body. Function body parsing code is similar enough
    522   // to be re-used for method bodies as well.
    523   ParseScope FnScope(this, Scope::FnScope|Scope::DeclScope);
    524   Actions.ActOnStartOfFunctionDef(getCurScope(), LM.D);
    525 
    526   if (Tok.is(tok::kw_try)) {
    527     ParseFunctionTryBlock(LM.D, FnScope);
    528 
    529     while (Tok.isNot(tok::eof))
    530       ConsumeAnyToken();
    531 
    532     if (Tok.is(tok::eof) && Tok.getEofData() == LM.D)
    533       ConsumeAnyToken();
    534     return;
    535   }
    536   if (Tok.is(tok::colon)) {
    537     ParseConstructorInitializer(LM.D);
    538 
    539     // Error recovery.
    540     if (!Tok.is(tok::l_brace)) {
    541       FnScope.Exit();
    542       Actions.ActOnFinishFunctionBody(LM.D, nullptr);
    543 
    544       while (Tok.isNot(tok::eof))
    545         ConsumeAnyToken();
    546 
    547       if (Tok.is(tok::eof) && Tok.getEofData() == LM.D)
    548         ConsumeAnyToken();
    549       return;
    550     }
    551   } else
    552     Actions.ActOnDefaultCtorInitializers(LM.D);
    553 
    554   assert((Actions.getDiagnostics().hasErrorOccurred() ||
    555           !isa<FunctionTemplateDecl>(LM.D) ||
    556           cast<FunctionTemplateDecl>(LM.D)->getTemplateParameters()->getDepth()
    557             < TemplateParameterDepth) &&
    558          "TemplateParameterDepth should be greater than the depth of "
    559          "current template being instantiated!");
    560 
    561   ParseFunctionStatementBody(LM.D, FnScope);
    562 
    563   // Clear the late-template-parsed bit if we set it before.
    564   if (LM.D)
    565     LM.D->getAsFunction()->setLateTemplateParsed(false);
    566 
    567   while (Tok.isNot(tok::eof))
    568     ConsumeAnyToken();
    569 
    570   if (Tok.is(tok::eof) && Tok.getEofData() == LM.D)
    571     ConsumeAnyToken();
    572 
    573   if (auto *FD = dyn_cast_or_null<FunctionDecl>(LM.D))
    574     if (isa<CXXMethodDecl>(FD) ||
    575         FD->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend))
    576       Actions.ActOnFinishInlineFunctionDef(FD);
    577 }
    578 
    579 /// ParseLexedMemberInitializers - We finished parsing the member specification
    580 /// of a top (non-nested) C++ class. Now go over the stack of lexed data member
    581 /// initializers that were collected during its parsing and parse them all.
    582 void Parser::ParseLexedMemberInitializers(ParsingClass &Class) {
    583   bool HasTemplateScope = !Class.TopLevelClass && Class.TemplateScope;
    584   ParseScope ClassTemplateScope(this, Scope::TemplateParamScope,
    585                                 HasTemplateScope);
    586   TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
    587   if (HasTemplateScope) {
    588     Actions.ActOnReenterTemplateScope(getCurScope(), Class.TagOrTemplate);
    589     ++CurTemplateDepthTracker;
    590   }
    591   // Set or update the scope flags.
    592   bool AlreadyHasClassScope = Class.TopLevelClass;
    593   unsigned ScopeFlags = Scope::ClassScope|Scope::DeclScope;
    594   ParseScope ClassScope(this, ScopeFlags, !AlreadyHasClassScope);
    595   ParseScopeFlags ClassScopeFlags(this, ScopeFlags, AlreadyHasClassScope);
    596 
    597   if (!AlreadyHasClassScope)
    598     Actions.ActOnStartDelayedMemberDeclarations(getCurScope(),
    599                                                 Class.TagOrTemplate);
    600 
    601   if (!Class.LateParsedDeclarations.empty()) {
    602     // C++11 [expr.prim.general]p4:
    603     //   Otherwise, if a member-declarator declares a non-static data member
    604     //  (9.2) of a class X, the expression this is a prvalue of type "pointer
    605     //  to X" within the optional brace-or-equal-initializer. It shall not
    606     //  appear elsewhere in the member-declarator.
    607     Sema::CXXThisScopeRAII ThisScope(Actions, Class.TagOrTemplate,
    608                                      /*TypeQuals=*/(unsigned)0);
    609 
    610     for (size_t i = 0; i < Class.LateParsedDeclarations.size(); ++i) {
    611       Class.LateParsedDeclarations[i]->ParseLexedMemberInitializers();
    612     }
    613   }
    614 
    615   if (!AlreadyHasClassScope)
    616     Actions.ActOnFinishDelayedMemberDeclarations(getCurScope(),
    617                                                  Class.TagOrTemplate);
    618 
    619   Actions.ActOnFinishDelayedMemberInitializers(Class.TagOrTemplate);
    620 }
    621 
    622 void Parser::ParseLexedMemberInitializer(LateParsedMemberInitializer &MI) {
    623   if (!MI.Field || MI.Field->isInvalidDecl())
    624     return;
    625 
    626   // Append the current token at the end of the new token stream so that it
    627   // doesn't get lost.
    628   MI.Toks.push_back(Tok);
    629   PP.EnterTokenStream(MI.Toks, true);
    630 
    631   // Consume the previously pushed token.
    632   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
    633 
    634   SourceLocation EqualLoc;
    635 
    636   Actions.ActOnStartCXXInClassMemberInitializer();
    637 
    638   ExprResult Init = ParseCXXMemberInitializer(MI.Field, /*IsFunction=*/false,
    639                                               EqualLoc);
    640 
    641   Actions.ActOnFinishCXXInClassMemberInitializer(MI.Field, EqualLoc,
    642                                                  Init.get());
    643 
    644   // The next token should be our artificial terminating EOF token.
    645   if (Tok.isNot(tok::eof)) {
    646     if (!Init.isInvalid()) {
    647       SourceLocation EndLoc = PP.getLocForEndOfToken(PrevTokLocation);
    648       if (!EndLoc.isValid())
    649         EndLoc = Tok.getLocation();
    650       // No fixit; we can't recover as if there were a semicolon here.
    651       Diag(EndLoc, diag::err_expected_semi_decl_list);
    652     }
    653 
    654     // Consume tokens until we hit the artificial EOF.
    655     while (Tok.isNot(tok::eof))
    656       ConsumeAnyToken();
    657   }
    658   // Make sure this is *our* artificial EOF token.
    659   if (Tok.getEofData() == MI.Field)
    660     ConsumeAnyToken();
    661 }
    662 
    663 /// ConsumeAndStoreUntil - Consume and store the token at the passed token
    664 /// container until the token 'T' is reached (which gets
    665 /// consumed/stored too, if ConsumeFinalToken).
    666 /// If StopAtSemi is true, then we will stop early at a ';' character.
    667 /// Returns true if token 'T1' or 'T2' was found.
    668 /// NOTE: This is a specialized version of Parser::SkipUntil.
    669 bool Parser::ConsumeAndStoreUntil(tok::TokenKind T1, tok::TokenKind T2,
    670                                   CachedTokens &Toks,
    671                                   bool StopAtSemi, bool ConsumeFinalToken) {
    672   // We always want this function to consume at least one token if the first
    673   // token isn't T and if not at EOF.
    674   bool isFirstTokenConsumed = true;
    675   while (1) {
    676     // If we found one of the tokens, stop and return true.
    677     if (Tok.is(T1) || Tok.is(T2)) {
    678       if (ConsumeFinalToken) {
    679         Toks.push_back(Tok);
    680         ConsumeAnyToken();
    681       }
    682       return true;
    683     }
    684 
    685     switch (Tok.getKind()) {
    686     case tok::eof:
    687     case tok::annot_module_begin:
    688     case tok::annot_module_end:
    689     case tok::annot_module_include:
    690       // Ran out of tokens.
    691       return false;
    692 
    693     case tok::l_paren:
    694       // Recursively consume properly-nested parens.
    695       Toks.push_back(Tok);
    696       ConsumeParen();
    697       ConsumeAndStoreUntil(tok::r_paren, Toks, /*StopAtSemi=*/false);
    698       break;
    699     case tok::l_square:
    700       // Recursively consume properly-nested square brackets.
    701       Toks.push_back(Tok);
    702       ConsumeBracket();
    703       ConsumeAndStoreUntil(tok::r_square, Toks, /*StopAtSemi=*/false);
    704       break;
    705     case tok::l_brace:
    706       // Recursively consume properly-nested braces.
    707       Toks.push_back(Tok);
    708       ConsumeBrace();
    709       ConsumeAndStoreUntil(tok::r_brace, Toks, /*StopAtSemi=*/false);
    710       break;
    711 
    712     // Okay, we found a ']' or '}' or ')', which we think should be balanced.
    713     // Since the user wasn't looking for this token (if they were, it would
    714     // already be handled), this isn't balanced.  If there is a LHS token at a
    715     // higher level, we will assume that this matches the unbalanced token
    716     // and return it.  Otherwise, this is a spurious RHS token, which we skip.
    717     case tok::r_paren:
    718       if (ParenCount && !isFirstTokenConsumed)
    719         return false;  // Matches something.
    720       Toks.push_back(Tok);
    721       ConsumeParen();
    722       break;
    723     case tok::r_square:
    724       if (BracketCount && !isFirstTokenConsumed)
    725         return false;  // Matches something.
    726       Toks.push_back(Tok);
    727       ConsumeBracket();
    728       break;
    729     case tok::r_brace:
    730       if (BraceCount && !isFirstTokenConsumed)
    731         return false;  // Matches something.
    732       Toks.push_back(Tok);
    733       ConsumeBrace();
    734       break;
    735 
    736     case tok::code_completion:
    737       Toks.push_back(Tok);
    738       ConsumeCodeCompletionToken();
    739       break;
    740 
    741     case tok::string_literal:
    742     case tok::wide_string_literal:
    743     case tok::utf8_string_literal:
    744     case tok::utf16_string_literal:
    745     case tok::utf32_string_literal:
    746       Toks.push_back(Tok);
    747       ConsumeStringToken();
    748       break;
    749     case tok::semi:
    750       if (StopAtSemi)
    751         return false;
    752       // FALL THROUGH.
    753     default:
    754       // consume this token.
    755       Toks.push_back(Tok);
    756       ConsumeToken();
    757       break;
    758     }
    759     isFirstTokenConsumed = false;
    760   }
    761 }
    762 
    763 /// \brief Consume tokens and store them in the passed token container until
    764 /// we've passed the try keyword and constructor initializers and have consumed
    765 /// the opening brace of the function body. The opening brace will be consumed
    766 /// if and only if there was no error.
    767 ///
    768 /// \return True on error.
    769 bool Parser::ConsumeAndStoreFunctionPrologue(CachedTokens &Toks) {
    770   if (Tok.is(tok::kw_try)) {
    771     Toks.push_back(Tok);
    772     ConsumeToken();
    773   }
    774 
    775   if (Tok.isNot(tok::colon)) {
    776     // Easy case, just a function body.
    777 
    778     // Grab any remaining garbage to be diagnosed later. We stop when we reach a
    779     // brace: an opening one is the function body, while a closing one probably
    780     // means we've reached the end of the class.
    781     ConsumeAndStoreUntil(tok::l_brace, tok::r_brace, Toks,
    782                          /*StopAtSemi=*/true,
    783                          /*ConsumeFinalToken=*/false);
    784     if (Tok.isNot(tok::l_brace))
    785       return Diag(Tok.getLocation(), diag::err_expected) << tok::l_brace;
    786 
    787     Toks.push_back(Tok);
    788     ConsumeBrace();
    789     return false;
    790   }
    791 
    792   Toks.push_back(Tok);
    793   ConsumeToken();
    794 
    795   // We can't reliably skip over a mem-initializer-id, because it could be
    796   // a template-id involving not-yet-declared names. Given:
    797   //
    798   //   S ( ) : a < b < c > ( e )
    799   //
    800   // 'e' might be an initializer or part of a template argument, depending
    801   // on whether 'b' is a template.
    802 
    803   // Track whether we might be inside a template argument. We can give
    804   // significantly better diagnostics if we know that we're not.
    805   bool MightBeTemplateArgument = false;
    806 
    807   while (true) {
    808     // Skip over the mem-initializer-id, if possible.
    809     if (Tok.is(tok::kw_decltype)) {
    810       Toks.push_back(Tok);
    811       SourceLocation OpenLoc = ConsumeToken();
    812       if (Tok.isNot(tok::l_paren))
    813         return Diag(Tok.getLocation(), diag::err_expected_lparen_after)
    814                  << "decltype";
    815       Toks.push_back(Tok);
    816       ConsumeParen();
    817       if (!ConsumeAndStoreUntil(tok::r_paren, Toks, /*StopAtSemi=*/true)) {
    818         Diag(Tok.getLocation(), diag::err_expected) << tok::r_paren;
    819         Diag(OpenLoc, diag::note_matching) << tok::l_paren;
    820         return true;
    821       }
    822     }
    823     do {
    824       // Walk over a component of a nested-name-specifier.
    825       if (Tok.is(tok::coloncolon)) {
    826         Toks.push_back(Tok);
    827         ConsumeToken();
    828 
    829         if (Tok.is(tok::kw_template)) {
    830           Toks.push_back(Tok);
    831           ConsumeToken();
    832         }
    833       }
    834 
    835       if (Tok.isOneOf(tok::identifier, tok::kw_template)) {
    836         Toks.push_back(Tok);
    837         ConsumeToken();
    838       } else if (Tok.is(tok::code_completion)) {
    839         Toks.push_back(Tok);
    840         ConsumeCodeCompletionToken();
    841         // Consume the rest of the initializers permissively.
    842         // FIXME: We should be able to perform code-completion here even if
    843         //        there isn't a subsequent '{' token.
    844         MightBeTemplateArgument = true;
    845         break;
    846       } else {
    847         break;
    848       }
    849     } while (Tok.is(tok::coloncolon));
    850 
    851     if (Tok.is(tok::less))
    852       MightBeTemplateArgument = true;
    853 
    854     if (MightBeTemplateArgument) {
    855       // We may be inside a template argument list. Grab up to the start of the
    856       // next parenthesized initializer or braced-init-list. This *might* be the
    857       // initializer, or it might be a subexpression in the template argument
    858       // list.
    859       // FIXME: Count angle brackets, and clear MightBeTemplateArgument
    860       //        if all angles are closed.
    861       if (!ConsumeAndStoreUntil(tok::l_paren, tok::l_brace, Toks,
    862                                 /*StopAtSemi=*/true,
    863                                 /*ConsumeFinalToken=*/false)) {
    864         // We're not just missing the initializer, we're also missing the
    865         // function body!
    866         return Diag(Tok.getLocation(), diag::err_expected) << tok::l_brace;
    867       }
    868     } else if (Tok.isNot(tok::l_paren) && Tok.isNot(tok::l_brace)) {
    869       // We found something weird in a mem-initializer-id.
    870       if (getLangOpts().CPlusPlus11)
    871         return Diag(Tok.getLocation(), diag::err_expected_either)
    872                << tok::l_paren << tok::l_brace;
    873       else
    874         return Diag(Tok.getLocation(), diag::err_expected) << tok::l_paren;
    875     }
    876 
    877     tok::TokenKind kind = Tok.getKind();
    878     Toks.push_back(Tok);
    879     bool IsLParen = (kind == tok::l_paren);
    880     SourceLocation OpenLoc = Tok.getLocation();
    881 
    882     if (IsLParen) {
    883       ConsumeParen();
    884     } else {
    885       assert(kind == tok::l_brace && "Must be left paren or brace here.");
    886       ConsumeBrace();
    887       // In C++03, this has to be the start of the function body, which
    888       // means the initializer is malformed; we'll diagnose it later.
    889       if (!getLangOpts().CPlusPlus11)
    890         return false;
    891     }
    892 
    893     // Grab the initializer (or the subexpression of the template argument).
    894     // FIXME: If we support lambdas here, we'll need to set StopAtSemi to false
    895     //        if we might be inside the braces of a lambda-expression.
    896     tok::TokenKind CloseKind = IsLParen ? tok::r_paren : tok::r_brace;
    897     if (!ConsumeAndStoreUntil(CloseKind, Toks, /*StopAtSemi=*/true)) {
    898       Diag(Tok, diag::err_expected) << CloseKind;
    899       Diag(OpenLoc, diag::note_matching) << kind;
    900       return true;
    901     }
    902 
    903     // Grab pack ellipsis, if present.
    904     if (Tok.is(tok::ellipsis)) {
    905       Toks.push_back(Tok);
    906       ConsumeToken();
    907     }
    908 
    909     // If we know we just consumed a mem-initializer, we must have ',' or '{'
    910     // next.
    911     if (Tok.is(tok::comma)) {
    912       Toks.push_back(Tok);
    913       ConsumeToken();
    914     } else if (Tok.is(tok::l_brace)) {
    915       // This is the function body if the ')' or '}' is immediately followed by
    916       // a '{'. That cannot happen within a template argument, apart from the
    917       // case where a template argument contains a compound literal:
    918       //
    919       //   S ( ) : a < b < c > ( d ) { }
    920       //   // End of declaration, or still inside the template argument?
    921       //
    922       // ... and the case where the template argument contains a lambda:
    923       //
    924       //   S ( ) : a < 0 && b < c > ( d ) + [ ] ( ) { return 0; }
    925       //     ( ) > ( ) { }
    926       //
    927       // FIXME: Disambiguate these cases. Note that the latter case is probably
    928       //        going to be made ill-formed by core issue 1607.
    929       Toks.push_back(Tok);
    930       ConsumeBrace();
    931       return false;
    932     } else if (!MightBeTemplateArgument) {
    933       return Diag(Tok.getLocation(), diag::err_expected_either) << tok::l_brace
    934                                                                 << tok::comma;
    935     }
    936   }
    937 }
    938 
    939 /// \brief Consume and store tokens from the '?' to the ':' in a conditional
    940 /// expression.
    941 bool Parser::ConsumeAndStoreConditional(CachedTokens &Toks) {
    942   // Consume '?'.
    943   assert(Tok.is(tok::question));
    944   Toks.push_back(Tok);
    945   ConsumeToken();
    946 
    947   while (Tok.isNot(tok::colon)) {
    948     if (!ConsumeAndStoreUntil(tok::question, tok::colon, Toks,
    949                               /*StopAtSemi=*/true,
    950                               /*ConsumeFinalToken=*/false))
    951       return false;
    952 
    953     // If we found a nested conditional, consume it.
    954     if (Tok.is(tok::question) && !ConsumeAndStoreConditional(Toks))
    955       return false;
    956   }
    957 
    958   // Consume ':'.
    959   Toks.push_back(Tok);
    960   ConsumeToken();
    961   return true;
    962 }
    963 
    964 /// \brief A tentative parsing action that can also revert token annotations.
    965 class Parser::UnannotatedTentativeParsingAction : public TentativeParsingAction {
    966 public:
    967   explicit UnannotatedTentativeParsingAction(Parser &Self,
    968                                              tok::TokenKind EndKind)
    969       : TentativeParsingAction(Self), Self(Self), EndKind(EndKind) {
    970     // Stash away the old token stream, so we can restore it once the
    971     // tentative parse is complete.
    972     TentativeParsingAction Inner(Self);
    973     Self.ConsumeAndStoreUntil(EndKind, Toks, true, /*ConsumeFinalToken*/false);
    974     Inner.Revert();
    975   }
    976 
    977   void RevertAnnotations() {
    978     Revert();
    979 
    980     // Put back the original tokens.
    981     Self.SkipUntil(EndKind, StopAtSemi | StopBeforeMatch);
    982     if (Toks.size()) {
    983       auto Buffer = llvm::make_unique<Token[]>(Toks.size());
    984       std::copy(Toks.begin() + 1, Toks.end(), Buffer.get());
    985       Buffer[Toks.size() - 1] = Self.Tok;
    986       Self.PP.EnterTokenStream(std::move(Buffer), Toks.size(), true);
    987 
    988       Self.Tok = Toks.front();
    989     }
    990   }
    991 
    992 private:
    993   Parser &Self;
    994   CachedTokens Toks;
    995   tok::TokenKind EndKind;
    996 };
    997 
    998 /// ConsumeAndStoreInitializer - Consume and store the token at the passed token
    999 /// container until the end of the current initializer expression (either a
   1000 /// default argument or an in-class initializer for a non-static data member).
   1001 ///
   1002 /// Returns \c true if we reached the end of something initializer-shaped,
   1003 /// \c false if we bailed out.
   1004 bool Parser::ConsumeAndStoreInitializer(CachedTokens &Toks,
   1005                                         CachedInitKind CIK) {
   1006   // We always want this function to consume at least one token if not at EOF.
   1007   bool IsFirstToken = true;
   1008 
   1009   // Number of possible unclosed <s we've seen so far. These might be templates,
   1010   // and might not, but if there were none of them (or we know for sure that
   1011   // we're within a template), we can avoid a tentative parse.
   1012   unsigned AngleCount = 0;
   1013   unsigned KnownTemplateCount = 0;
   1014 
   1015   while (1) {
   1016     switch (Tok.getKind()) {
   1017     case tok::comma:
   1018       // If we might be in a template, perform a tentative parse to check.
   1019       if (!AngleCount)
   1020         // Not a template argument: this is the end of the initializer.
   1021         return true;
   1022       if (KnownTemplateCount)
   1023         goto consume_token;
   1024 
   1025       // We hit a comma inside angle brackets. This is the hard case. The
   1026       // rule we follow is:
   1027       //  * For a default argument, if the tokens after the comma form a
   1028       //    syntactically-valid parameter-declaration-clause, in which each
   1029       //    parameter has an initializer, then this comma ends the default
   1030       //    argument.
   1031       //  * For a default initializer, if the tokens after the comma form a
   1032       //    syntactically-valid init-declarator-list, then this comma ends
   1033       //    the default initializer.
   1034       {
   1035         UnannotatedTentativeParsingAction PA(*this,
   1036                                              CIK == CIK_DefaultInitializer
   1037                                                ? tok::semi : tok::r_paren);
   1038         Sema::TentativeAnalysisScope Scope(Actions);
   1039 
   1040         TPResult Result = TPResult::Error;
   1041         ConsumeToken();
   1042         switch (CIK) {
   1043         case CIK_DefaultInitializer:
   1044           Result = TryParseInitDeclaratorList();
   1045           // If we parsed a complete, ambiguous init-declarator-list, this
   1046           // is only syntactically-valid if it's followed by a semicolon.
   1047           if (Result == TPResult::Ambiguous && Tok.isNot(tok::semi))
   1048             Result = TPResult::False;
   1049           break;
   1050 
   1051         case CIK_DefaultArgument:
   1052           bool InvalidAsDeclaration = false;
   1053           Result = TryParseParameterDeclarationClause(
   1054               &InvalidAsDeclaration, /*VersusTemplateArgument=*/true);
   1055           // If this is an expression or a declaration with a missing
   1056           // 'typename', assume it's not a declaration.
   1057           if (Result == TPResult::Ambiguous && InvalidAsDeclaration)
   1058             Result = TPResult::False;
   1059           break;
   1060         }
   1061 
   1062         // If what follows could be a declaration, it is a declaration.
   1063         if (Result != TPResult::False && Result != TPResult::Error) {
   1064           PA.Revert();
   1065           return true;
   1066         }
   1067 
   1068         // In the uncommon case that we decide the following tokens are part
   1069         // of a template argument, revert any annotations we've performed in
   1070         // those tokens. We're not going to look them up until we've parsed
   1071         // the rest of the class, and that might add more declarations.
   1072         PA.RevertAnnotations();
   1073       }
   1074 
   1075       // Keep going. We know we're inside a template argument list now.
   1076       ++KnownTemplateCount;
   1077       goto consume_token;
   1078 
   1079     case tok::eof:
   1080     case tok::annot_module_begin:
   1081     case tok::annot_module_end:
   1082     case tok::annot_module_include:
   1083       // Ran out of tokens.
   1084       return false;
   1085 
   1086     case tok::less:
   1087       // FIXME: A '<' can only start a template-id if it's preceded by an
   1088       // identifier, an operator-function-id, or a literal-operator-id.
   1089       ++AngleCount;
   1090       goto consume_token;
   1091 
   1092     case tok::question:
   1093       // In 'a ? b : c', 'b' can contain an unparenthesized comma. If it does,
   1094       // that is *never* the end of the initializer. Skip to the ':'.
   1095       if (!ConsumeAndStoreConditional(Toks))
   1096         return false;
   1097       break;
   1098 
   1099     case tok::greatergreatergreater:
   1100       if (!getLangOpts().CPlusPlus11)
   1101         goto consume_token;
   1102       if (AngleCount) --AngleCount;
   1103       if (KnownTemplateCount) --KnownTemplateCount;
   1104       // Fall through.
   1105     case tok::greatergreater:
   1106       if (!getLangOpts().CPlusPlus11)
   1107         goto consume_token;
   1108       if (AngleCount) --AngleCount;
   1109       if (KnownTemplateCount) --KnownTemplateCount;
   1110       // Fall through.
   1111     case tok::greater:
   1112       if (AngleCount) --AngleCount;
   1113       if (KnownTemplateCount) --KnownTemplateCount;
   1114       goto consume_token;
   1115 
   1116     case tok::kw_template:
   1117       // 'template' identifier '<' is known to start a template argument list,
   1118       // and can be used to disambiguate the parse.
   1119       // FIXME: Support all forms of 'template' unqualified-id '<'.
   1120       Toks.push_back(Tok);
   1121       ConsumeToken();
   1122       if (Tok.is(tok::identifier)) {
   1123         Toks.push_back(Tok);
   1124         ConsumeToken();
   1125         if (Tok.is(tok::less)) {
   1126           ++AngleCount;
   1127           ++KnownTemplateCount;
   1128           Toks.push_back(Tok);
   1129           ConsumeToken();
   1130         }
   1131       }
   1132       break;
   1133 
   1134     case tok::kw_operator:
   1135       // If 'operator' precedes other punctuation, that punctuation loses
   1136       // its special behavior.
   1137       Toks.push_back(Tok);
   1138       ConsumeToken();
   1139       switch (Tok.getKind()) {
   1140       case tok::comma:
   1141       case tok::greatergreatergreater:
   1142       case tok::greatergreater:
   1143       case tok::greater:
   1144       case tok::less:
   1145         Toks.push_back(Tok);
   1146         ConsumeToken();
   1147         break;
   1148       default:
   1149         break;
   1150       }
   1151       break;
   1152 
   1153     case tok::l_paren:
   1154       // Recursively consume properly-nested parens.
   1155       Toks.push_back(Tok);
   1156       ConsumeParen();
   1157       ConsumeAndStoreUntil(tok::r_paren, Toks, /*StopAtSemi=*/false);
   1158       break;
   1159     case tok::l_square:
   1160       // Recursively consume properly-nested square brackets.
   1161       Toks.push_back(Tok);
   1162       ConsumeBracket();
   1163       ConsumeAndStoreUntil(tok::r_square, Toks, /*StopAtSemi=*/false);
   1164       break;
   1165     case tok::l_brace:
   1166       // Recursively consume properly-nested braces.
   1167       Toks.push_back(Tok);
   1168       ConsumeBrace();
   1169       ConsumeAndStoreUntil(tok::r_brace, Toks, /*StopAtSemi=*/false);
   1170       break;
   1171 
   1172     // Okay, we found a ']' or '}' or ')', which we think should be balanced.
   1173     // Since the user wasn't looking for this token (if they were, it would
   1174     // already be handled), this isn't balanced.  If there is a LHS token at a
   1175     // higher level, we will assume that this matches the unbalanced token
   1176     // and return it.  Otherwise, this is a spurious RHS token, which we
   1177     // consume and pass on to downstream code to diagnose.
   1178     case tok::r_paren:
   1179       if (CIK == CIK_DefaultArgument)
   1180         return true; // End of the default argument.
   1181       if (ParenCount && !IsFirstToken)
   1182         return false;
   1183       Toks.push_back(Tok);
   1184       ConsumeParen();
   1185       continue;
   1186     case tok::r_square:
   1187       if (BracketCount && !IsFirstToken)
   1188         return false;
   1189       Toks.push_back(Tok);
   1190       ConsumeBracket();
   1191       continue;
   1192     case tok::r_brace:
   1193       if (BraceCount && !IsFirstToken)
   1194         return false;
   1195       Toks.push_back(Tok);
   1196       ConsumeBrace();
   1197       continue;
   1198 
   1199     case tok::code_completion:
   1200       Toks.push_back(Tok);
   1201       ConsumeCodeCompletionToken();
   1202       break;
   1203 
   1204     case tok::string_literal:
   1205     case tok::wide_string_literal:
   1206     case tok::utf8_string_literal:
   1207     case tok::utf16_string_literal:
   1208     case tok::utf32_string_literal:
   1209       Toks.push_back(Tok);
   1210       ConsumeStringToken();
   1211       break;
   1212     case tok::semi:
   1213       if (CIK == CIK_DefaultInitializer)
   1214         return true; // End of the default initializer.
   1215       // FALL THROUGH.
   1216     default:
   1217     consume_token:
   1218       Toks.push_back(Tok);
   1219       ConsumeToken();
   1220       break;
   1221     }
   1222     IsFirstToken = false;
   1223   }
   1224 }
   1225