--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/gcc.dg/cpp/strp1.c	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,35 @@
+/* { dg-do run } */
+
+/* Regression test for stringizing and token pasting.
+   We got internal escape markers in the strings.  */
+
+#include <string.h>
+#include <stdlib.h>
+
+#define S(x) _S(x)
+#define _S(x) #x
+
+#define I 1
+static const char s1[] = S(I.1);
+static const char t1[] = "1.1";
+
+#define f h
+#define h(a) a+f
+static const char s2[] = S( f(1)(2) );
+static const char t2[] = "1+h(2)";
+
+#undef I
+#undef f
+#undef h
+
+int
+main(void)
+{
+  if (strcmp (s1, t1))
+    abort ();
+
+  if (strcmp (s2, t2))
+    abort ();
+
+  return 0;
+}