MS ABI: Mangle alias templates used as template-template arguments

A templated using declaration may be used as a template-template
argument.

Unfortunately, the VS "14" chooses '?' as the sole marker for the
argument.  This is problematic because it presupposes the possibility of
using more than one template-aliases as arguments to the same template.

This fixes PR20047.

llvm-svn: 214290

1 files changed, 14 insertions, 0 deletions

diff --git a/clang/test/CodeGenCXX/mangle-ms-cxx11.cpp b/clang/test/CodeGenCXX/mangle-ms-cxx11.cpp
index 373d2b7b957..cb9c64fc9a2 100644
--- a/clang/test/CodeGenCXX/mangle-ms-cxx11.cpp
+++ b/clang/test/CodeGenCXX/mangle-ms-cxx11.cpp
@@ -139,3 +139,17 @@ void templ_fun_with_pack() {}
 
 template void templ_fun_with_pack<>();
 // CHECK-DAG: @"\01??$templ_fun_with_pack@$S@@YAXXZ"
+
+namespace PR20047 {
+template <typename T>
+struct A {};
+
+template <typename T>
+using AliasA = A<T>;
+
+template <template <typename> class>
+void f() {}
+
+template void f<AliasA>();
+// CHECK-DAG: @"\01??$f@?@PR20047@@YAXXZ"
+}