--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/gcc.dg/cpp/strify4.c	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,29 @@
+/* { dg-do run } */
+/* Tests we stringify without changing unprintable characts.  
+
+   Andrew Pinski */
+
+extern int strcmp (const char *, const char *);
+#if DEBUG
+extern int puts (const char *);
+#else
+#define puts(X)
+#endif
+extern void abort (void);
+#define err(str) do { puts(str); abort(); } while (0)
+
+
+#define S(X) S2(X)
+#define S2(X) #X
+#define TAB "	" /* Note there is a tab character here. */
+
+int main (int argc, char *argv[])
+{
+  /* The space before "bar" here is vital.  */
+  char a[] = S(S(TAB));
+
+  if (strcmp (a, "\"\\\"	\\\"\""))
+    err ("stringification caused octal");
+
+  return 0;
+}