--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/parse/array-size2.C	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,20 @@
+// PR c/25682
+// { dg-do compile }
+// Test whether we don't ICE on questionable constructs where offsetof
+// should have been used instead.
+
+struct S
+{
+  char a[4];
+  int b;
+};
+
+extern void bar (char *, char *);
+
+void
+foo (void)
+{
+  char g[(char *) &((struct S *) 0)->b - (char *) 0]; // { dg-error "constant" }
+  char h[(__SIZE_TYPE__) &((struct S *) 8)->b];	      // { dg-error "constant" "" { xfail *-*-* } }
+  bar (g, h);
+}