3 files changed, 16 insertions, 4 deletions
diff --git a/clang/lib/AST/TypeLoc.cpp b/clang/lib/AST/TypeLoc.cpp
index 66578fb3dc4..0ba9fc00876 100644
--- a/clang/lib/AST/TypeLoc.cpp
+++ b/clang/lib/AST/TypeLoc.cpp
@@ -94,6 +94,13 @@ void TypeLoc::initializeImpl(TypeLoc TL, SourceLocation Loc) {
   }
 }
 
+/// \brief Initializes a type location by copying all its data from
+/// another type location of the same type.
+void TypeLoc::initializeFullCopyImpl(TypeLoc TL, TypeLoc Other) {
+  assert(TL.getType() == Other.getType() && "Must copy from same type");
+  memcpy(TL.getOpaqueData(), Other.getOpaqueData(), TL.getFullDataSize());
+}
+
 SourceLocation TypeLoc::getBeginLoc() const {
   TypeLoc Cur = *this;
   while (true) {
diff --git a/clang/lib/Parse/ParseDeclCXX.cpp b/clang/lib/Parse/ParseDeclCXX.cpp
index 140f1491017..1bc5815f21e 100644
--- a/clang/lib/Parse/ParseDeclCXX.cpp
+++ b/clang/lib/Parse/ParseDeclCXX.cpp
@@ -908,7 +908,7 @@ void Parser::ParseClassSpecifier(tok::TokenKind TagTokKind,
                                       TemplateArgsPtr,
                                       TemplateId->RAngleLoc);
 
-      TypeResult = Actions.ActOnTagTemplateIdType(TypeResult, TUK,
+      TypeResult = Actions.ActOnTagTemplateIdType(SS, TypeResult, TUK,
                                                   TagType, StartLoc);
     } else {
       // This is an explicit specialization or a class template
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 4c25bc32df5..daa1e726a06 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -1646,14 +1646,14 @@ Sema::ActOnTemplateIdType(TemplateTy TemplateD, SourceLocation TemplateLoc,
   return CreateParsedType(Result, DI);
 }
 
-TypeResult Sema::ActOnTagTemplateIdType(TypeResult TypeResult,
+TypeResult Sema::ActOnTagTemplateIdType(CXXScopeSpec &SS,
+                                        TypeResult TypeResult,
                                         TagUseKind TUK,
                                         TypeSpecifierType TagSpec,
                                         SourceLocation TagLoc) {
   if (TypeResult.isInvalid())
     return ::TypeResult();
 
-  // FIXME: preserve source info, ideally without copying the DI.
   TypeSourceInfo *DI;
   QualType Type = GetTypeFromParser(TypeResult.get(), &DI);
 
@@ -1678,7 +1678,12 @@ TypeResult Sema::ActOnTagTemplateIdType(TypeResult TypeResult,
     = TypeWithKeyword::getKeywordForTagTypeKind(TagKind);
   QualType ElabType = Context.getElaboratedType(Keyword, /*NNS=*/0, Type);
 
-  return ParsedType::make(ElabType);
+  TypeSourceInfo *ElabDI = Context.CreateTypeSourceInfo(ElabType);
+  ElaboratedTypeLoc TL = cast<ElaboratedTypeLoc>(ElabDI->getTypeLoc());
+  TL.setKeywordLoc(TagLoc);
+  TL.setQualifierRange(SS.getRange());
+  TL.getNamedTypeLoc().initializeFullCopy(DI->getTypeLoc());
+  return CreateParsedType(ElabType, ElabDI);
 }
 
 ExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS,