Change the context correctly when instantiating a static data member definition.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@125517 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Sema/SemaTemplateInstantiateDecl.cpp

@@ -2434,13 +2434,13 @@ void Sema::InstantiateStaticDataMemberDefinition(
 
   // Enter the scope of this instantiation. We don't use
   // PushDeclContext because we don't have a scope.
-  DeclContext *PreviousContext = CurContext;
-  CurContext = Var->getDeclContext();
+  ContextRAII previousContext(*this, Var->getDeclContext());
 
   VarDecl *OldVar = Var;
   Var = cast_or_null<VarDecl>(SubstDecl(Def, Var->getDeclContext(),
                                         getTemplateInstantiationArgs(Var)));
-  CurContext = PreviousContext;
+
+  previousContext.pop();
 
   if (Var) {
     MemberSpecializationInfo *MSInfo = OldVar->getMemberSpecializationInfo();

test/CXX/class.access/p4.cpp

@@ -498,3 +498,13 @@ namespace rdar8876150 {
     return !b;
   }
 }
+
+namespace test23 {
+  template <typename T> class A {
+    A();
+    static A instance;
+  };
+
+  template <typename T> A<T> A<T>::instance;
+  template class A<int>;
+}