Check in LLVM r95781.
diff --git a/test/CodeGenCXX/vtable-key-function.cpp b/test/CodeGenCXX/vtable-key-function.cpp
new file mode 100644
index 0000000..97a546f
--- /dev/null
+++ b/test/CodeGenCXX/vtable-key-function.cpp
@@ -0,0 +1,33 @@
+// RUN: %clang_cc1 %s -triple=x86_64-apple-darwin10 -emit-llvm -o - | FileCheck %s
+// PR5697
+namespace PR5697 {
+struct A {
+ virtual void f() { }
+ A();
+ A(int);
+};
+
+// A does not have a key function, so the first constructor we emit should
+// cause the vtable to be defined (without assertions.)
+// CHECK: @_ZTVN6PR56971AE = weak_odr constant
+A::A() { }
+A::A(int) { }
+}
+
+// Make sure that we don't assert when building the vtable for a class
+// template specialization or explicit instantiation with a key
+// function.
+template<typename T>
+struct Base {
+ virtual ~Base();
+};
+
+template<typename T>
+struct Derived : public Base<T> { };
+
+template<>
+struct Derived<char> : public Base<char> {
+ virtual void anchor();
+};
+
+void Derived<char>::anchor() { }