From 11d00cf9721ddb12c336fb7b7c8ca39ba722a448 Mon Sep 17 00:00:00 2001
From: Anders Carlsson <andersca@mac.com>
Date: Tue, 6 Oct 2009 21:58:01 +0000
Subject: [PATCH] When mangling names, always use the canonical decl. Fixes
 PR5144.

llvm-svn: 83420
---
 clang/lib/CodeGen/Mangle.cpp     | 2 +-
 clang/test/CodeGenCXX/mangle.cpp | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/clang/lib/CodeGen/Mangle.cpp b/clang/lib/CodeGen/Mangle.cpp
index 7555ae5da467..702edf05a962 100644
--- a/clang/lib/CodeGen/Mangle.cpp
+++ b/clang/lib/CodeGen/Mangle.cpp
@@ -1303,7 +1303,7 @@ namespace clang {
                                    "Mangling declaration");
     
     CXXNameMangler Mangler(Context, os);
-    if (!Mangler.mangle(D))
+    if (!Mangler.mangle(cast<NamedDecl>(D->getCanonicalDecl())))
       return false;
 
     os.flush();
diff --git a/clang/test/CodeGenCXX/mangle.cpp b/clang/test/CodeGenCXX/mangle.cpp
index 86f5fb0d5bbd..a881a710d490 100644
--- a/clang/test/CodeGenCXX/mangle.cpp
+++ b/clang/test/CodeGenCXX/mangle.cpp
@@ -198,3 +198,12 @@ template<typename T> typename __enable_if<__is_scalar<T>::__value, void>::__type
 template void ft7<int>();
 // CHECK: @_Z3ft7IPvEN11__enable_ifIXsr11__is_scalarIT_E7__valueEvE6__typeEv
 template void ft7<void*>();
+
+// PR5144
+extern "C" {
+void extern_f(void);
+};
+
+// CHECK: @extern_f
+void extern_f(void) { }
+