PR12798: Don't drop part of the nested name specifier when instantiating a

pseudo-destructor expression. This can affect whether virtual dispatch for
the destructor call is bypassed.

llvm-svn: 156806

clang/lib/Sema/TreeTransform.h

@@ -9268,7 +9268,11 @@ TreeTransform<Derived>::RebuildCXXPseudoDestructorExpr(Expr *Base,
   DeclarationNameInfo NameInfo(Name, Destroyed.getLocation());
   NameInfo.setNamedTypeInfo(DestroyedType);
 
-  // FIXME: the ScopeType should be tacked onto SS.
+  // The scope type is now known to be a valid nested name specifier
+  // component. Tack it on to the end of the nested name specifier.
+  if (ScopeType)
+    SS.Extend(SemaRef.Context, SourceLocation(),
+              ScopeType->getTypeLoc(), CCLoc);
 
   SourceLocation TemplateKWLoc; // FIXME: retrieve it from caller.
   return getSema().BuildMemberReferenceExpr(Base, BaseType,

clang/test/CodeGenCXX/virtual-destructor-calls.cpp

@@ -46,3 +46,14 @@ C::~C() { }
 // CHECK: call void @_ZdlPv
 
 // Base dtor: just an alias to B's base dtor.
+
+namespace PR12798 {
+  // A qualified call to a base class destructor should not undergo virtual
+  // dispatch. Template instantiation used to lose the qualifier.
+  struct A { virtual ~A(); };
+  template<typename T> void f(T *p) { p->A::~A(); }
+
+  // CHECK: define {{.*}} @_ZN7PR127981fINS_1AEEEvPT_(
+  // CHECK: call void @_ZN7PR127981AD1Ev(
+  template void f(A*);
+}