Mangle ::std::basic_string as Sb.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@82881 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGenCXX/mangle-subst-std.cpp b/test/CodeGenCXX/mangle-subst-std.cpp
index 0fd5eb1..c35804e 100644
--- a/test/CodeGenCXX/mangle-subst-std.cpp
+++ b/test/CodeGenCXX/mangle-subst-std.cpp
@@ -9,10 +9,19 @@
 };
 
 namespace std {
-  template<typename T> struct allocator { allocator(); };
+  template<typename T> struct allocator { };
 }
 
 // FIXME: typename is really not allowed here, but it's kept 
 // as a workaround for PR5061.
 // CHECK: define void @_Z1fSaIcESaIiE
 void f(typename std::allocator<char>, typename std::allocator<int>) { }
+
+namespace std {
+  template<typename T> struct basic_string { };
+}
+
+// FIXME: typename is really not allowed here, but it's kept 
+// as a workaround for PR5061.
+// CHECK: define void @_Z1fSbIcESbIiE
+void f(typename std::basic_string<char>, typename std::basic_string<int>) { }