diff --git a/clang/lib/CodeGen/Mangle.cpp b/clang/lib/CodeGen/Mangle.cpp
index 639d719b79fb..ff2388e79830 100644
--- a/clang/lib/CodeGen/Mangle.cpp
+++ b/clang/lib/CodeGen/Mangle.cpp
@@ -1149,6 +1149,12 @@ bool CXXNameMangler::mangleStandardSubstitution(const NamedDecl *ND) {
       Out << "Sa";
       return true;
     }
+    
+    // <<substitution> ::= Sb # ::std::basic_string
+    if (TD->getIdentifier()->isStr("basic_string")) {
+      Out << "Sb";
+      return true;
+    }
   }
   
   return false;
diff --git a/clang/test/CodeGenCXX/mangle-subst-std.cpp b/clang/test/CodeGenCXX/mangle-subst-std.cpp
index 0fd5eb1c9b90..c35804e2d35f 100644
--- a/clang/test/CodeGenCXX/mangle-subst-std.cpp
+++ b/clang/test/CodeGenCXX/mangle-subst-std.cpp
@@ -9,10 +9,19 @@ namespace std {
 };
 
 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>) { }