--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/gcc.dg/cpp/trad/mi3.c	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,20 @@
+/* Another test case for over-eager multiple include optimization.
+   This one distilled from glibc's setlocale.c and categories.def.  */
+/* { dg-do compile } */
+
+#define X a
+#include "mi3.def"
+#undef X
+
+#define X b
+#include "mi3.def"
+#undef X
+
+#include "mi3.h"
+#include "mi3.h"  /* The second include declares variable c.  */
+
+int
+main(void)
+{
+  return a + b + c;
+}