3 files changed, 25 insertions, 3 deletions
diff --git a/clang/lib/AST/DeclTemplate.cpp b/clang/lib/AST/DeclTemplate.cpp
index 6e734a18c75..0b0228869ef 100644
--- a/clang/lib/AST/DeclTemplate.cpp
+++ b/clang/lib/AST/DeclTemplate.cpp
@@ -963,6 +963,16 @@ void VarTemplateDecl::DeallocateCommon(void *Ptr) {
   static_cast<Common *>(Ptr)->~Common();
 }
 
+VarTemplateDecl *VarTemplateDecl::getDefinition() {
+  VarTemplateDecl *CurD = this;
+  while (CurD) {
+    if (CurD->isThisDeclarationADefinition())
+      return CurD;
+    CurD = CurD->getPreviousDecl();
+  }
+  return 0;
+}
+
 VarTemplateDecl *VarTemplateDecl::Create(ASTContext &C, DeclContext *DC,
                                          SourceLocation L, DeclarationName Name,
                                          TemplateParameterList *Params,
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 315a405c6d3..5766afa1011 100644
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -3481,11 +3481,22 @@ void Sema::InstantiateVariableDefinition(SourceLocation PointOfInstantiation,
     llvm::PointerUnion<VarTemplateDecl *,
                        VarTemplatePartialSpecializationDecl *> PatternPtr =
         VarSpec->getSpecializedTemplateOrPartial();
-    if (PatternPtr.is<VarTemplatePartialSpecializationDecl *>())
+    if (PatternPtr.is<VarTemplatePartialSpecializationDecl *>()) {
       PatternDecl = cast<VarDecl>(
           PatternPtr.get<VarTemplatePartialSpecializationDecl *>());
-    else
-      PatternDecl = (PatternPtr.get<VarTemplateDecl *>())->getTemplatedDecl();
+
+      // Find actual definition
+      if (VarDecl *Def = PatternDecl->getDefinition(getASTContext()))
+        PatternDecl = Def;
+    } else {
+      VarTemplateDecl *PatternTemplate = PatternPtr.get<VarTemplateDecl *>();
+
+      // Find actual definition
+      if (VarTemplateDecl *Def = PatternTemplate->getDefinition())
+        PatternTemplate = Def;
+
+      PatternDecl = PatternTemplate->getTemplatedDecl();
+    }
     assert(PatternDecl && "instantiating a non-template");
   }
 
diff --git a/clang/lib/Serialization/ASTWriterDecl.cpp b/clang/lib/Serialization/ASTWriterDecl.cpp
index 60acbc585ba..bb7fd1edf6e 100644
--- a/clang/lib/Serialization/ASTWriterDecl.cpp
+++ b/clang/lib/Serialization/ASTWriterDecl.cpp
@@ -735,6 +735,7 @@ void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
       D->getInitStyle() == VarDecl::CInit &&
       D->getInit() == 0 &&
       !isa<ParmVarDecl>(D) &&
+      !isa<VarTemplateSpecializationDecl>(D) &&
       !D->isConstexpr() &&
       !SpecInfo)
     AbbrevToUse = Writer.getDeclVarAbbrev();