re PR tree-optimization/57385 ([tree-ssa] Possible segfault in fully_constant_vn_reference_p)

	PR tree-ssa/57385
	* gcc.dg/tree-ssa/pr57385.c: New test.

From-SVN: r199283

gcc/testsuite/gcc.dg/tree-ssa/pr57385.c

+/* { dg-do compile } */
+/* { dg-options "-O1" } */
+
+int c;
+
+void foo(int f)
+{
+  int wbi=-100000000;
+  c = (f ? "012346000000000000":"01345:000000006008")[wbi];
+}