MFC 261991:

Upgrade our copy of llvm/clang to 3.4 release.  This version supports
all of the features in the current working draft of the upcoming C++
standard, provisionally named C++1y.

The code generator's performance is greatly increased, and the loop
auto-vectorizer is now enabled at -Os and -O2 in addition to -O3.  The
PowerPC backend has made several major improvements to code generation
quality and compile time, and the X86, SPARC, ARM32, Aarch64 and SystemZ
backends have all seen major feature work.

Release notes for llvm and clang can be found here:
<http://llvm.org/releases/3.4/docs/ReleaseNotes.html>
<http://llvm.org/releases/3.4/tools/clang/docs/ReleaseNotes.html>

MFC 262121 (by emaste):

Update lldb for clang/llvm 3.4 import

This commit largely restores the lldb source to the upstream r196259
snapshot with the addition of threaded inferior support and a few bug
fixes.

Specific upstream lldb revisions restored include:
   SVN      git
  181387  779e6ac
  181703  7bef4e2
  182099  b31044e
  182650  f2dcf35
  182683  0d91b80
  183862  15c1774
  183929  99447a6
  184177  0b2934b
  184948  4dc3761
  184954  007e7bc
  186990  eebd175

Sponsored by:	DARPA, AFRL

MFC 262186 (by emaste):

Fix mismerge in r262121

A break statement was lost in the merge.  The error had no functional
impact, but restore it to reduce the diff against upstream.

MFC 262303:

Pull in r197521 from upstream clang trunk (by rdivacky):

  Use the integrated assembler by default on FreeBSD/ppc and ppc64.

Requested by:	jhibbits

MFC 262611:

Pull in r196874 from upstream llvm trunk:

  Fix a crash that occurs when PWD is invalid.

  MCJIT needs to be able to run in hostile environments, even when PWD
  is invalid. There's no need to crash MCJIT in this case.

  The obvious fix is to simply leave MCContext's CompilationDir empty
  when PWD can't be determined. This way, MCJIT clients,
  and other clients that link with LLVM don't need a valid working directory.

  If we do want to guarantee valid CompilationDir, that should be done
  only for clients of getCompilationDir(). This is as simple as checking
  for an empty string.

  The only current use of getCompilationDir is EmitGenDwarfInfo, which
  won't conceivably run with an invalid working dir. However, in the
  purely hypothetically and untestable case that this happens, the
  AT_comp_dir will be omitted from the compilation_unit DIE.

This should help fix assertions occurring with ports-mgmt/tinderbox,
when it is using jails, and sometimes invalidates clang's current
working directory.

Reported by:	decke

MFC 262809:

Pull in r203007 from upstream clang trunk:

  Don't produce an alias between destructors with different calling conventions.

  Fixes pr19007.

(Please note that is an LLVM PR identifier, not a FreeBSD one.)

This should fix Firefox and/or libxul crashes (due to problems with
regparm/stdcall calling conventions) on i386.

Reported by:	multiple users on freebsd-current
PR:		bin/187103

MFC 263048:

Repair recognition of "CC" as an alias for the C++ compiler, since it
was silently broken by upstream for a Windows-specific use-case.

Apparently some versions of CMake still rely on this archaic feature...

Reported by:	rakuco

MFC 263049:

Garbage collect the old way of adding the libstdc++ include directories
in clang's InitHeaderSearch.cpp.  This has been superseded by David
Chisnall's commit in r255321.

Moreover, if libc++ is used, the libstdc++ include directories should
not be in the search path at all.  These directories are now only used
if you pass -stdlib=libstdc++.

1 files changed, 457 insertions, 91 deletions

diff --git a/contrib/llvm/tools/clang/lib/Parse/ParseCXXInlineMethods.cpp b/contrib/llvm/tools/clang/lib/Parse/ParseCXXInlineMethods.cpp
index 5fc4189..7792305 100644
--- a/contrib/llvm/tools/clang/lib/Parse/ParseCXXInlineMethods.cpp
+++ b/contrib/llvm/tools/clang/lib/Parse/ParseCXXInlineMethods.cpp
@@ -55,11 +55,10 @@ NamedDecl *Parser::ParseCXXInlineMethodDef(AccessSpecifier AS,
                                            TemplateParams, 0,
                                            VS, ICIS_NoInit);
     if (FnD) {
-      Actions.ProcessDeclAttributeList(getCurScope(), FnD, AccessAttrs,
-                                       false, true);
+      Actions.ProcessDeclAttributeList(getCurScope(), FnD, AccessAttrs);
       bool TypeSpecContainsAuto = D.getDeclSpec().containsPlaceholderType();
       if (Init.isUsable())
-        Actions.AddInitializerToDecl(FnD, Init.get(), false, 
+        Actions.AddInitializerToDecl(FnD, Init.get(), false,
                                      TypeSpecContainsAuto);
       else
         Actions.ActOnUninitializedDecl(FnD, TypeSpecContainsAuto);
@@ -110,28 +109,27 @@ NamedDecl *Parser::ParseCXXInlineMethodDef(AccessSpecifier AS,
 
     return FnD;
   }
-
+  
   // In delayed template parsing mode, if we are within a class template
   // or if we are about to parse function member template then consume
   // the tokens and store them for parsing at the end of the translation unit.
-  if (getLangOpts().DelayedTemplateParsing && 
-      DefinitionKind == FDK_Definition && 
+  if (getLangOpts().DelayedTemplateParsing &&
+      DefinitionKind == FDK_Definition &&
+      !D.getDeclSpec().isConstexprSpecified() && 
+      !(FnD && getFunctionDecl(FnD) && 
+          getFunctionDecl(FnD)->getResultType()->getContainedAutoType()) &&
       ((Actions.CurContext->isDependentContext() ||
-        TemplateInfo.Kind != ParsedTemplateInfo::NonTemplate) && 
-        !Actions.IsInsideALocalClassWithinATemplateFunction())) {
+        (TemplateInfo.Kind != ParsedTemplateInfo::NonTemplate &&
+         TemplateInfo.Kind != ParsedTemplateInfo::ExplicitSpecialization)) &&
+       !Actions.IsInsideALocalClassWithinATemplateFunction())) {
 
-    if (FnD) {
-      LateParsedTemplatedFunction *LPT = new LateParsedTemplatedFunction(FnD);
+    CachedTokens Toks;
+    LexTemplateFunctionForLateParsing(Toks);
 
+    if (FnD) {
       FunctionDecl *FD = getFunctionDecl(FnD);
       Actions.CheckForFunctionRedefinition(FD);
-
-      LateParsedTemplateMap[FD] = LPT;
-      Actions.MarkAsLateParsedTemplate(FD);
-      LexTemplateFunctionForLateParsing(LPT->Toks);
-    } else {
-      CachedTokens Toks;
-      LexTemplateFunctionForLateParsing(Toks);
+      Actions.MarkAsLateParsedTemplate(FD, FnD, Toks);
     }
 
     return FnD;
@@ -151,9 +149,9 @@ NamedDecl *Parser::ParseCXXInlineMethodDef(AccessSpecifier AS,
     // We didn't find the left-brace we expected after the
     // constructor initializer; we already printed an error, and it's likely
     // impossible to recover, so don't try to parse this method later.
-    // If we stopped at a semicolon, consume it to avoid an extra warning.
-     if (Tok.is(tok::semi))
-      ConsumeToken();
+    // Skip over the rest of the decl and back to somewhere that looks
+    // reasonable.
+    SkipMalformedDecl();
     delete getCurrentClass().LateParsedDeclarations.back();
     getCurrentClass().LateParsedDeclarations.pop_back();
     return FnD;
@@ -170,27 +168,28 @@ NamedDecl *Parser::ParseCXXInlineMethodDef(AccessSpecifier AS,
     }
   }
 
-
-  if (!FnD) {
+  if (FnD) {
+    // If this is a friend function, mark that it's late-parsed so that
+    // it's still known to be a definition even before we attach the
+    // parsed body.  Sema needs to treat friend function definitions
+    // differently during template instantiation, and it's possible for
+    // the containing class to be instantiated before all its member
+    // function definitions are parsed.
+    //
+    // If you remove this, you can remove the code that clears the flag
+    // after parsing the member.
+    if (D.getDeclSpec().isFriendSpecified()) {
+      FunctionDecl *FD = getFunctionDecl(FnD);
+      Actions.CheckForFunctionRedefinition(FD);
+      FD->setLateTemplateParsed(true);
+    }
+  } else {
     // If semantic analysis could not build a function declaration,
     // just throw away the late-parsed declaration.
     delete getCurrentClass().LateParsedDeclarations.back();
     getCurrentClass().LateParsedDeclarations.pop_back();
   }
 
-  // If this is a friend function, mark that it's late-parsed so that
-  // it's still known to be a definition even before we attach the
-  // parsed body.  Sema needs to treat friend function definitions
-  // differently during template instantiation, and it's possible for
-  // the containing class to be instantiated before all its member
-  // function definitions are parsed.
-  //
-  // If you remove this, you can remove the code that clears the flag
-  // after parsing the member.
-  if (D.getDeclSpec().isFriendSpecified()) {
-    getFunctionDecl(FnD)->setLateTemplateParsed(true);
-  }
-
   return FnD;
 }
 
@@ -222,8 +221,7 @@ void Parser::ParseCXXNonStaticMemberInitializer(Decl *VarD) {
     ConsumeAndStoreUntil(tok::r_brace, Toks, /*StopAtSemi=*/true);
   } else {
     // Consume everything up to (but excluding) the comma or semicolon.
-    ConsumeAndStoreUntil(tok::comma, Toks, /*StopAtSemi=*/true,
-                         /*ConsumeFinalToken=*/false);
+    ConsumeAndStoreInitializer(Toks, CIK_DefaultInitializer);
   }
 
   // Store an artificial EOF token to ensure that we don't run off the end of
@@ -352,8 +350,15 @@ void Parser::ParseLexedMethodDeclaration(LateParsedMethodDeclaration &LM) {
       else {
         if (Tok.is(tok::cxx_defaultarg_end))
           ConsumeToken();
-        else
-          Diag(Tok.getLocation(), diag::err_default_arg_unparsed);
+        else {
+          // The last two tokens are the terminator and the saved value of
+          // Tok; the last token in the default argument is the one before
+          // those.
+          assert(Toks->size() >= 3 && "expected a token in default arg");
+          Diag(Tok.getLocation(), diag::err_default_arg_unparsed)
+            << SourceRange(Tok.getLocation(),
+                           (*Toks)[Toks->size() - 3].getLocation());
+        }
         Actions.ActOnParamDefaultArgument(LM.DefaultArgs[I].Param, EqualLoc,
                                           DefArgResult.take());
       }
@@ -653,83 +658,444 @@ bool Parser::ConsumeAndStoreUntil(tok::TokenKind T1, tok::TokenKind T2,
 /// the opening brace of the function body. The opening brace will be consumed
 /// if and only if there was no error.
 ///
-/// \return True on error. 
+/// \return True on error.
 bool Parser::ConsumeAndStoreFunctionPrologue(CachedTokens &Toks) {
   if (Tok.is(tok::kw_try)) {
     Toks.push_back(Tok);
     ConsumeToken();
   }
-  bool ReadInitializer = false;
-  if (Tok.is(tok::colon)) {
-    // Initializers can contain braces too.
+
+  if (Tok.isNot(tok::colon)) {
+    // Easy case, just a function body.
+
+    // Grab any remaining garbage to be diagnosed later. We stop when we reach a
+    // brace: an opening one is the function body, while a closing one probably
+    // means we've reached the end of the class.
+    ConsumeAndStoreUntil(tok::l_brace, tok::r_brace, Toks,
+                         /*StopAtSemi=*/true,
+                         /*ConsumeFinalToken=*/false);
+    if (Tok.isNot(tok::l_brace))
+      return Diag(Tok.getLocation(), diag::err_expected_lbrace);
+
     Toks.push_back(Tok);
-    ConsumeToken();
+    ConsumeBrace();
+    return false;
+  }
 
-    while (Tok.is(tok::identifier) || Tok.is(tok::coloncolon)) {
-      if (Tok.is(tok::eof) || Tok.is(tok::semi))
-        return Diag(Tok.getLocation(), diag::err_expected_lbrace);
+  Toks.push_back(Tok);
+  ConsumeToken();
 
-      // Grab the identifier.
-      if (!ConsumeAndStoreUntil(tok::l_paren, tok::l_brace, Toks,
-                                /*StopAtSemi=*/true,
-                                /*ConsumeFinalToken=*/false))
-        return Diag(Tok.getLocation(), diag::err_expected_lparen);
+  // We can't reliably skip over a mem-initializer-id, because it could be
+  // a template-id involving not-yet-declared names. Given:
+  //
+  //   S ( ) : a < b < c > ( e )
+  //
+  // 'e' might be an initializer or part of a template argument, depending
+  // on whether 'b' is a template.
+
+  // Track whether we might be inside a template argument. We can give
+  // significantly better diagnostics if we know that we're not.
+  bool MightBeTemplateArgument = false;
 
-      tok::TokenKind kind = Tok.getKind();
+  while (true) {
+    // Skip over the mem-initializer-id, if possible.
+    if (Tok.is(tok::kw_decltype)) {
       Toks.push_back(Tok);
-      bool IsLParen = (kind == tok::l_paren);
-      SourceLocation LOpen = Tok.getLocation();
+      SourceLocation OpenLoc = ConsumeToken();
+      if (Tok.isNot(tok::l_paren))
+        return Diag(Tok.getLocation(), diag::err_expected_lparen_after)
+                 << "decltype";
+      Toks.push_back(Tok);
+      ConsumeParen();
+      if (!ConsumeAndStoreUntil(tok::r_paren, Toks, /*StopAtSemi=*/true)) {
+        Diag(Tok.getLocation(), diag::err_expected_rparen);
+        Diag(OpenLoc, diag::note_matching) << "(";
+        return true;
+      }
+    }
+    do {
+      // Walk over a component of a nested-name-specifier.
+      if (Tok.is(tok::coloncolon)) {
+        Toks.push_back(Tok);
+        ConsumeToken();
 
-      if (IsLParen) {
-        ConsumeParen();
+        if (Tok.is(tok::kw_template)) {
+          Toks.push_back(Tok);
+          ConsumeToken();
+        }
+      }
+
+      if (Tok.is(tok::identifier) || Tok.is(tok::kw_template)) {
+        Toks.push_back(Tok);
+        ConsumeToken();
+      } else if (Tok.is(tok::code_completion)) {
+        Toks.push_back(Tok);
+        ConsumeCodeCompletionToken();
+        // Consume the rest of the initializers permissively.
+        // FIXME: We should be able to perform code-completion here even if
+        //        there isn't a subsequent '{' token.
+        MightBeTemplateArgument = true;
+        break;
       } else {
-        assert(kind == tok::l_brace && "Must be left paren or brace here.");
-        ConsumeBrace();
-        // In C++03, this has to be the start of the function body, which
-        // means the initializer is malformed; we'll diagnose it later.
-        if (!getLangOpts().CPlusPlus11)
-          return false;
+        break;
       }
+    } while (Tok.is(tok::coloncolon));
+
+    if (Tok.is(tok::less))
+      MightBeTemplateArgument = true;
+
+    if (MightBeTemplateArgument) {
+      // We may be inside a template argument list. Grab up to the start of the
+      // next parenthesized initializer or braced-init-list. This *might* be the
+      // initializer, or it might be a subexpression in the template argument
+      // list.
+      // FIXME: Count angle brackets, and clear MightBeTemplateArgument
+      //        if all angles are closed.
+      if (!ConsumeAndStoreUntil(tok::l_paren, tok::l_brace, Toks,
+                                /*StopAtSemi=*/true,
+                                /*ConsumeFinalToken=*/false)) {
+        // We're not just missing the initializer, we're also missing the
+        // function body!
+        return Diag(Tok.getLocation(), diag::err_expected_lbrace);
+      }
+    } else if (Tok.isNot(tok::l_paren) && Tok.isNot(tok::l_brace)) {
+      // We found something weird in a mem-initializer-id.
+      return Diag(Tok.getLocation(), getLangOpts().CPlusPlus11
+                                         ? diag::err_expected_lparen_or_lbrace
+                                         : diag::err_expected_lparen);
+    }
+
+    tok::TokenKind kind = Tok.getKind();
+    Toks.push_back(Tok);
+    bool IsLParen = (kind == tok::l_paren);
+    SourceLocation OpenLoc = Tok.getLocation();
+
+    if (IsLParen) {
+      ConsumeParen();
+    } else {
+      assert(kind == tok::l_brace && "Must be left paren or brace here.");
+      ConsumeBrace();
+      // In C++03, this has to be the start of the function body, which
+      // means the initializer is malformed; we'll diagnose it later.
+      if (!getLangOpts().CPlusPlus11)
+        return false;
+    }
 
-      // Grab the initializer
-      if (!ConsumeAndStoreUntil(IsLParen ? tok::r_paren : tok::r_brace,
-                                Toks, /*StopAtSemi=*/true)) {
-        Diag(Tok, IsLParen ? diag::err_expected_rparen :
-                             diag::err_expected_rbrace);
-        Diag(LOpen, diag::note_matching) << (IsLParen ? "(" : "{");
+    // Grab the initializer (or the subexpression of the template argument).
+    // FIXME: If we support lambdas here, we'll need to set StopAtSemi to false
+    //        if we might be inside the braces of a lambda-expression.
+    if (!ConsumeAndStoreUntil(IsLParen ? tok::r_paren : tok::r_brace,
+                              Toks, /*StopAtSemi=*/true)) {
+      Diag(Tok, IsLParen ? diag::err_expected_rparen :
+                           diag::err_expected_rbrace);
+      Diag(OpenLoc, diag::note_matching) << (IsLParen ? "(" : "{");
+      return true;
+    }
+
+    // Grab pack ellipsis, if present.
+    if (Tok.is(tok::ellipsis)) {
+      Toks.push_back(Tok);
+      ConsumeToken();
+    }
+
+    // If we know we just consumed a mem-initializer, we must have ',' or '{'
+    // next.
+    if (Tok.is(tok::comma)) {
+      Toks.push_back(Tok);
+      ConsumeToken();
+    } else if (Tok.is(tok::l_brace)) {
+      // This is the function body if the ')' or '}' is immediately followed by
+      // a '{'. That cannot happen within a template argument, apart from the
+      // case where a template argument contains a compound literal:
+      //
+      //   S ( ) : a < b < c > ( d ) { }
+      //   // End of declaration, or still inside the template argument?
+      //
+      // ... and the case where the template argument contains a lambda:
+      //
+      //   S ( ) : a < 0 && b < c > ( d ) + [ ] ( ) { return 0; }
+      //     ( ) > ( ) { }
+      //
+      // FIXME: Disambiguate these cases. Note that the latter case is probably
+      //        going to be made ill-formed by core issue 1607.
+      Toks.push_back(Tok);
+      ConsumeBrace();
+      return false;
+    } else if (!MightBeTemplateArgument) {
+      return Diag(Tok.getLocation(), diag::err_expected_lbrace_or_comma);
+    }
+  }
+}
+
+/// \brief Consume and store tokens from the '?' to the ':' in a conditional
+/// expression.
+bool Parser::ConsumeAndStoreConditional(CachedTokens &Toks) {
+  // Consume '?'.
+  assert(Tok.is(tok::question));
+  Toks.push_back(Tok);
+  ConsumeToken();
+
+  while (Tok.isNot(tok::colon)) {
+    if (!ConsumeAndStoreUntil(tok::question, tok::colon, Toks, /*StopAtSemi*/true,
+                              /*ConsumeFinalToken*/false))
+      return false;
+
+    // If we found a nested conditional, consume it.
+    if (Tok.is(tok::question) && !ConsumeAndStoreConditional(Toks))
+      return false;
+  }
+
+  // Consume ':'.
+  Toks.push_back(Tok);
+  ConsumeToken();
+  return true;
+}
+
+/// \brief A tentative parsing action that can also revert token annotations.
+class Parser::UnannotatedTentativeParsingAction : public TentativeParsingAction {
+public:
+  explicit UnannotatedTentativeParsingAction(Parser &Self,
+                                             tok::TokenKind EndKind)
+      : TentativeParsingAction(Self), Self(Self), EndKind(EndKind) {
+    // Stash away the old token stream, so we can restore it once the
+    // tentative parse is complete.
+    TentativeParsingAction Inner(Self);
+    Self.ConsumeAndStoreUntil(EndKind, Toks, true, /*ConsumeFinalToken*/false);
+    Inner.Revert();
+  }
+
+  void RevertAnnotations() {
+    Revert();
+
+    // Put back the original tokens.
+    Self.SkipUntil(EndKind, StopAtSemi | StopBeforeMatch);
+    if (Toks.size()) {
+      Token *Buffer = new Token[Toks.size()];
+      std::copy(Toks.begin() + 1, Toks.end(), Buffer);
+      Buffer[Toks.size() - 1] = Self.Tok;
+      Self.PP.EnterTokenStream(Buffer, Toks.size(), true, /*Owned*/true);
+
+      Self.Tok = Toks.front();
+    }
+  }
+
+private:
+  Parser &Self;
+  CachedTokens Toks;
+  tok::TokenKind EndKind;
+};
+
+/// ConsumeAndStoreInitializer - Consume and store the token at the passed token
+/// container until the end of the current initializer expression (either a
+/// default argument or an in-class initializer for a non-static data member).
+/// The final token is not consumed.
+bool Parser::ConsumeAndStoreInitializer(CachedTokens &Toks,
+                                        CachedInitKind CIK) {
+  // We always want this function to consume at least one token if not at EOF.
+  bool IsFirstTokenConsumed = true;
+
+  // Number of possible unclosed <s we've seen so far. These might be templates,
+  // and might not, but if there were none of them (or we know for sure that
+  // we're within a template), we can avoid a tentative parse.
+  unsigned AngleCount = 0;
+  unsigned KnownTemplateCount = 0;
+
+  while (1) {
+    switch (Tok.getKind()) {
+    case tok::comma:
+      // If we might be in a template, perform a tentative parse to check.
+      if (!AngleCount)
+        // Not a template argument: this is the end of the initializer.
         return true;
+      if (KnownTemplateCount)
+        goto consume_token;
+
+      // We hit a comma inside angle brackets. This is the hard case. The
+      // rule we follow is:
+      //  * For a default argument, if the tokens after the comma form a
+      //    syntactically-valid parameter-declaration-clause, in which each
+      //    parameter has an initializer, then this comma ends the default
+      //    argument.
+      //  * For a default initializer, if the tokens after the comma form a
+      //    syntactically-valid init-declarator-list, then this comma ends
+      //    the default initializer.
+      {
+        UnannotatedTentativeParsingAction PA(*this,
+                                             CIK == CIK_DefaultInitializer
+                                               ? tok::semi : tok::r_paren);
+        Sema::TentativeAnalysisScope Scope(Actions);
+
+        TPResult Result = TPResult::Error();
+        ConsumeToken();
+        switch (CIK) {
+        case CIK_DefaultInitializer:
+          Result = TryParseInitDeclaratorList();
+          // If we parsed a complete, ambiguous init-declarator-list, this
+          // is only syntactically-valid if it's followed by a semicolon.
+          if (Result == TPResult::Ambiguous() && Tok.isNot(tok::semi))
+            Result = TPResult::False();
+          break;
+
+        case CIK_DefaultArgument:
+          bool InvalidAsDeclaration = false;
+          Result = TryParseParameterDeclarationClause(
+              &InvalidAsDeclaration, /*VersusTemplateArgument*/true);
+          // If this is an expression or a declaration with a missing
+          // 'typename', assume it's not a declaration.
+          if (Result == TPResult::Ambiguous() && InvalidAsDeclaration)
+            Result = TPResult::False();
+          break;
+        }
+
+        // If what follows could be a declaration, it is a declaration.
+        if (Result != TPResult::False() && Result != TPResult::Error()) {
+          PA.Revert();
+          return true;
+        }
+
+        // In the uncommon case that we decide the following tokens are part
+        // of a template argument, revert any annotations we've performed in
+        // those tokens. We're not going to look them up until we've parsed
+        // the rest of the class, and that might add more declarations.
+        PA.RevertAnnotations();
       }
 
-      // Grab pack ellipsis, if present
-      if (Tok.is(tok::ellipsis)) {
+      // Keep going. We know we're inside a template argument list now.
+      ++KnownTemplateCount;
+      goto consume_token;
+
+    case tok::eof:
+      // Ran out of tokens.
+      return false;
+
+    case tok::less:
+      // FIXME: A '<' can only start a template-id if it's preceded by an
+      // identifier, an operator-function-id, or a literal-operator-id.
+      ++AngleCount;
+      goto consume_token;
+
+    case tok::question:
+      // In 'a ? b : c', 'b' can contain an unparenthesized comma. If it does,
+      // that is *never* the end of the initializer. Skip to the ':'.
+      if (!ConsumeAndStoreConditional(Toks))
+        return false;
+      break;
+
+    case tok::greatergreatergreater:
+      if (!getLangOpts().CPlusPlus11)
+        goto consume_token;
+      if (AngleCount) --AngleCount;
+      if (KnownTemplateCount) --KnownTemplateCount;
+      // Fall through.
+    case tok::greatergreater:
+      if (!getLangOpts().CPlusPlus11)
+        goto consume_token;
+      if (AngleCount) --AngleCount;
+      if (KnownTemplateCount) --KnownTemplateCount;
+      // Fall through.
+    case tok::greater:
+      if (AngleCount) --AngleCount;
+      if (KnownTemplateCount) --KnownTemplateCount;
+      goto consume_token;
+
+    case tok::kw_template:
+      // 'template' identifier '<' is known to start a template argument list,
+      // and can be used to disambiguate the parse.
+      // FIXME: Support all forms of 'template' unqualified-id '<'.
+      Toks.push_back(Tok);
+      ConsumeToken();
+      if (Tok.is(tok::identifier)) {
         Toks.push_back(Tok);
         ConsumeToken();
+        if (Tok.is(tok::less)) {
+          ++KnownTemplateCount;
+          Toks.push_back(Tok);
+          ConsumeToken();
+        }
       }
+      break;
 
-      // Grab the separating comma, if any.
-      if (Tok.is(tok::comma)) {
+    case tok::kw_operator:
+      // If 'operator' precedes other punctuation, that punctuation loses
+      // its special behavior.
+      Toks.push_back(Tok);
+      ConsumeToken();
+      switch (Tok.getKind()) {
+      case tok::comma:
+      case tok::greatergreatergreater:
+      case tok::greatergreater:
+      case tok::greater:
+      case tok::less:
         Toks.push_back(Tok);
         ConsumeToken();
-      } else if (Tok.isNot(tok::l_brace)) {
-        ReadInitializer = true;
+        break;
+      default:
         break;
       }
-    }
-  }
+      break;
 
-  // Grab any remaining garbage to be diagnosed later. We stop when we reach a
-  // brace: an opening one is the function body, while a closing one probably
-  // means we've reached the end of the class.
-  ConsumeAndStoreUntil(tok::l_brace, tok::r_brace, Toks,
-                       /*StopAtSemi=*/true,
-                       /*ConsumeFinalToken=*/false);
-  if (Tok.isNot(tok::l_brace)) {
-    if (ReadInitializer)
-      return Diag(Tok.getLocation(), diag::err_expected_lbrace_or_comma);
-    return Diag(Tok.getLocation(), diag::err_expected_lbrace);
-  }
+    case tok::l_paren:
+      // Recursively consume properly-nested parens.
+      Toks.push_back(Tok);
+      ConsumeParen();
+      ConsumeAndStoreUntil(tok::r_paren, Toks, /*StopAtSemi=*/false);
+      break;
+    case tok::l_square:
+      // Recursively consume properly-nested square brackets.
+      Toks.push_back(Tok);
+      ConsumeBracket();
+      ConsumeAndStoreUntil(tok::r_square, Toks, /*StopAtSemi=*/false);
+      break;
+    case tok::l_brace:
+      // Recursively consume properly-nested braces.
+      Toks.push_back(Tok);
+      ConsumeBrace();
+      ConsumeAndStoreUntil(tok::r_brace, Toks, /*StopAtSemi=*/false);
+      break;
 
-  Toks.push_back(Tok);
-  ConsumeBrace();
-  return false;
+    // Okay, we found a ']' or '}' or ')', which we think should be balanced.
+    // Since the user wasn't looking for this token (if they were, it would
+    // already be handled), this isn't balanced.  If there is a LHS token at a
+    // higher level, we will assume that this matches the unbalanced token
+    // and return it.  Otherwise, this is a spurious RHS token, which we skip.
+    case tok::r_paren:
+      if (CIK == CIK_DefaultArgument)
+        return true; // End of the default argument.
+      if (ParenCount && !IsFirstTokenConsumed)
+        return false;  // Matches something.
+      goto consume_token;
+    case tok::r_square:
+      if (BracketCount && !IsFirstTokenConsumed)
+        return false;  // Matches something.
+      goto consume_token;
+    case tok::r_brace:
+      if (BraceCount && !IsFirstTokenConsumed)
+        return false;  // Matches something.
+      goto consume_token;
+
+    case tok::code_completion:
+      Toks.push_back(Tok);
+      ConsumeCodeCompletionToken();
+      break;
+
+    case tok::string_literal:
+    case tok::wide_string_literal:
+    case tok::utf8_string_literal:
+    case tok::utf16_string_literal:
+    case tok::utf32_string_literal:
+      Toks.push_back(Tok);
+      ConsumeStringToken();
+      break;
+    case tok::semi:
+      if (CIK == CIK_DefaultInitializer)
+        return true; // End of the default initializer.
+      // FALL THROUGH.
+    default:
+    consume_token:
+      Toks.push_back(Tok);
+      ConsumeToken();
+      break;
+    }
+    IsFirstTokenConsumed = false;
+  }
 }