Check in LLVM r95781.
diff --git a/test/CodeGenCXX/mangle-system-header.cpp b/test/CodeGenCXX/mangle-system-header.cpp
new file mode 100644
index 0000000..cb68bc1
--- /dev/null
+++ b/test/CodeGenCXX/mangle-system-header.cpp
@@ -0,0 +1,7 @@
+// RUN: %clang_cc1 -emit-llvm %s -o - -triple=x86_64-apple-darwin9 | FileCheck %s
+
+// PR5420
+
+# 1 "fake_system_header.h" 1 3 4
+// CHECK: define void @_ZdlPvS_(
+void operator delete (void*, void*) {}