When adding initializers to a constructor, be sure that we are looking
through the bases and fields of the definition of the class in which
the constructor is declared, rather than some other declaration of
that class.

llvm-svn: 99661
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 1f6630e..1b4710e 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -1433,7 +1433,11 @@
                                   bool AnyErrors) {
   // We need to build the initializer AST according to order of construction
   // and not what user specified in the Initializers list.
-  CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Constructor->getDeclContext());
+  CXXRecordDecl *ClassDecl
+    = cast<CXXRecordDecl>(Constructor->getDeclContext())->getDefinition();
+  if (!ClassDecl)
+    return true;
+  
   llvm::SmallVector<CXXBaseOrMemberInitializer*, 32> AllToInit;
   llvm::DenseMap<const void *, CXXBaseOrMemberInitializer*> AllBaseFields;
   bool HasDependentBaseInit = false;
diff --git a/clang/test/CodeGenCXX/constructor-init.cpp b/clang/test/CodeGenCXX/constructor-init.cpp
index a0a35fa..284b8b5 100644
--- a/clang/test/CodeGenCXX/constructor-init.cpp
+++ b/clang/test/CodeGenCXX/constructor-init.cpp
@@ -80,3 +80,24 @@
   // CHECK-NOT: call void @_ZN1AIsED1Ev
   // CHECK: ret void
 }
+
+template<typename T>
+struct X {
+  X(const X &);
+
+  T *start;
+  T *end;
+};
+
+template<typename T> struct X;
+
+// Make sure that the instantiated constructor initializes start and
+// end properly.
+// CHECK: define linkonce_odr void @_ZN1XIiEC2ERKS0_
+// CHECK: {{store.*null}}
+// CHECK: {{store.*null}}
+// CHECK: ret
+template<typename T>
+X<T>::X(const X &other) : start(0), end(0) { }
+
+X<int> get_X(X<int> x) { return x; }