--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/torture/20180705-1.C	Thu Oct 25 07:37:49 2018 +0900
@@ -0,0 +1,30 @@
+// { dg-do compile }
+
+typedef long unsigned int size_t;
+extern void fancy_abort () __attribute__ ((__noreturn__));
+class cpp_string_location_reader { };
+class cpp_substring_ranges {
+public:
+    void add_range ();
+};
+typedef unsigned char uchar;
+void
+cpp_interpret_string_1 (size_t count, cpp_string_location_reader *loc_readers,    cpp_substring_ranges *ranges, uchar c, const uchar *p)
+{
+  size_t i;
+  ((void)(!((loc_readers !=   __null  ) == (ranges !=   __null  )) ? fancy_abort (), 0 : 0));
+  cpp_string_location_reader *loc_reader = __null;
+  for (i = 0; i < count; i++) 
+    {
+      if (loc_readers)  loc_reader = &loc_readers[i];
+      if (*p == 'R') 	continue;
+      for (;;) 	
+	{
+	  switch (c)     {
+	    case 'x':       if (ranges) ranges->add_range (); break;
+	    case '7':       ((void)(!((loc_reader !=   __null  ) == (ranges !=   __null  )) ? fancy_abort (), 0 : 0)); break;
+	  }
+	  p = 0;
+	}
+    }
+}