diff --git a/test/FrontendC/cstring-align.c b/test/FrontendC/cstring-align.c
new file mode 100644
index 00000000000..1320dd349b0
--- /dev/null
+++ b/test/FrontendC/cstring-align.c
@@ -0,0 +1,16 @@
+// RUN: %llvmgcc %s -c -Os -m32 -emit-llvm -o - | llc -march=x86 -mtriple=i386-apple-darwin10 | FileCheck %s -check-prefix=DARWIN32
+// RUN: %llvmgcc %s -c -Os -m64 -emit-llvm -o - | llc -march=x86 -mtriple=i386-apple-darwin10 | FileCheck %s -check-prefix=DARWIN64
+
+extern void func(const char *, const char *);
+
+void long_function_name() {
+  func("%s: the function name", __func__);
+}
+
+// DARWIN64: .align 3
+// DARWIN64: ___func__.
+// DARWIN64: .asciz "long_function_name"
+
+// DARWIN32: .align 2
+// DARWIN32: ___func__.
+// DARWIN32: .asciz "long_function_name"