Bug fix: disallow a variable template to be redeclared as a non-templated variable

llvm-svn: 188350

2 files changed, 27 insertions, 9 deletions

diff --git a/clang/lib/Serialization/ASTReaderDecl.cpp b/clang/lib/Serialization/ASTReaderDecl.cpp
index 1eef54b1421..7099d32b3d5 100644
--- a/clang/lib/Serialization/ASTReaderDecl.cpp
+++ b/clang/lib/Serialization/ASTReaderDecl.cpp
@@ -943,7 +943,7 @@ ASTDeclReader::RedeclarableResult ASTDeclReader::VisitVarDeclImpl(VarDecl *VD) {
   VD->setCachedLinkage(Linkage(Record[Idx++]));
 
   // Only true variables (not parameters or implicit parameters) can be merged.
-  if (VD->getKind() == Decl::Var)
+  if (VD->getKind() != Decl::ParmVar && VD->getKind() != Decl::ImplicitParam)
     mergeRedeclarable(VD, Redecl);
   
   if (uint64_t Val = Record[Idx++]) {
@@ -955,11 +955,22 @@ ASTDeclReader::RedeclarableResult ASTDeclReader::VisitVarDeclImpl(VarDecl *VD) {
     }
   }
 
-  if (Record[Idx++]) { // HasMemberSpecializationInfo.
+  enum VarKind {
+    VarNotTemplate = 0, VarTemplate, StaticDataMemberSpecialization
+  };
+  switch ((VarKind)Record[Idx++]) {
+  case VarNotTemplate:
+    break;
+  case VarTemplate:
+    VD->setDescribedVarTemplate(ReadDeclAs<VarTemplateDecl>(Record, Idx));
+    break;
+  case StaticDataMemberSpecialization: { // HasMemberSpecializationInfo.
     VarDecl *Tmpl = ReadDeclAs<VarDecl>(Record, Idx);
     TemplateSpecializationKind TSK = (TemplateSpecializationKind)Record[Idx++];
     SourceLocation POI = ReadSourceLocation(Record, Idx);
     Reader.getContext().setInstantiatedFromStaticDataMember(VD, Tmpl, TSK,POI);
+    break;
+  }
   }
 
   return Redecl;
@@ -1433,7 +1444,7 @@ void ASTDeclReader::VisitVarTemplateDecl(VarTemplateDecl *D) {
   RedeclarableResult Redecl = VisitRedeclarableTemplateDecl(D);
 
   if (ThisDeclID == Redecl.getFirstID()) {
-    // This ClassTemplateDecl owns a CommonPtr; read it to keep track of all of
+    // This VarTemplateDecl owns a CommonPtr; read it to keep track of all of
     // the specializations.
     SmallVector<serialization::DeclID, 2> SpecIDs;
     SpecIDs.push_back(0);
diff --git a/clang/lib/Serialization/ASTWriterDecl.cpp b/clang/lib/Serialization/ASTWriterDecl.cpp
index c9f3a6541f8..80726309417 100644
--- a/clang/lib/Serialization/ASTWriterDecl.cpp
+++ b/clang/lib/Serialization/ASTWriterDecl.cpp
@@ -712,14 +712,21 @@ void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
   } else {
     Record.push_back(0);
   }
-
-  MemberSpecializationInfo *SpecInfo
-    = D->isStaticDataMember() ? D->getMemberSpecializationInfo() : 0;
-  Record.push_back(SpecInfo != 0);
-  if (SpecInfo) {
+  
+  enum {
+    VarNotTemplate = 0, VarTemplate, StaticDataMemberSpecialization
+  };
+  if (VarTemplateDecl *TemplD = D->getDescribedVarTemplate()) {
+    Record.push_back(VarTemplate);
+    Writer.AddDeclRef(TemplD, Record);
+  } else if (MemberSpecializationInfo *SpecInfo
+               = D->getMemberSpecializationInfo()) {
+    Record.push_back(StaticDataMemberSpecialization);
     Writer.AddDeclRef(SpecInfo->getInstantiatedFrom(), Record);
     Record.push_back(SpecInfo->getTemplateSpecializationKind());
     Writer.AddSourceLocation(SpecInfo->getPointOfInstantiation(), Record);
+  } else {
+    Record.push_back(VarNotTemplate);
   }
 
   if (!D->hasAttrs() &&
@@ -739,7 +746,7 @@ void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
       !isa<VarTemplateSpecializationDecl>(D) &&
       !D->isConstexpr() &&
       !D->isPreviousDeclInSameBlockScope() &&
-      !SpecInfo)
+      !D->getMemberSpecializationInfo())
     AbbrevToUse = Writer.getDeclVarAbbrev();
 
   Code = serialization::DECL_VAR;