tree-chkp.c (chkp_compute_bounds_for_assignment): Handle POINTER_DIFF_EXPR.

	* tree-chkp.c (chkp_compute_bounds_for_assignment): Handle
	POINTER_DIFF_EXPR.

	* gcc.target/i386/mpx/pointer-diff-1.c: New test.

From-SVN: r255355

gcc/ChangeLog

 2017-12-02  Jakub Jelinek  <jakub@redhat.com>
 
+	* tree-chkp.c (chkp_compute_bounds_for_assignment): Handle
+	POINTER_DIFF_EXPR.
+
 	PR c++/81212
 	* tree-cfg.c (pass_warn_function_return::execute): Handle
 	__builtin_ubsan_handle_missing_return like __builtin_unreachable

gcc/testsuite/ChangeLog

 2017-12-02  Jakub Jelinek  <jakub@redhat.com>
 
+	* gcc.target/i386/mpx/pointer-diff-1.c: New test.
+
 	PR c++/81212
 	* g++.dg/ubsan/pr81212.C: New test.
 	* g++.dg/ubsan/return-1.C: Add -Wno-return-type to dg-options.

gcc/testsuite/gcc.target/i386/mpx/pointer-diff-1.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -mmpx -fcheck-pointer-bounds" } */
+
+char *
+foo (char *p, char *q)
+{
+  return (char *) (p - q);	/* { dg-bogus "pointer bounds were lost due to unexpected expression" } */
+}

gcc/tree-chkp.c

@@ -2762,6 +2762,7 @@ chkp_compute_bounds_for_assignment (tree node, gimple *assign)
     case FLOAT_EXPR:
     case REALPART_EXPR:
     case IMAGPART_EXPR:
+    case POINTER_DIFF_EXPR:
       /* No valid bounds may be produced by these exprs.  */
       bounds = chkp_get_invalid_op_bounds ();
       break;