Index: test/Preprocessor/macro.c
===================================================================
--- test/Preprocessor/macro.c
+++ test/Preprocessor/macro.c
@@ -0,0 +1,16 @@
+// RUN: %clang_cc1 -E -x c %s | FileCheck %s
+// The original bug requires UNIX line endings to trigger.
+
+// Make sure clang does not crash during preprocessing
+// CHECK-NOT: fatal error
+
+#define M0 extern int x;
+#define M2  M0  M0  M0  M0
+#define M4  M2  M2  M2  M2
+#define M6  M4  M4  M4  M4
+#define M8  M6  M6  M6  M6
+#define M10 M8  M8  M8  M8
+#define M12 M10 M10 M10 M10
+#define M14 M12 M12 M12 M12
+
+M14