re PR c++/83713 (ICE in do_narrow at gcc/convert.c:474)

2018-01-08  Richard Biener  <rguenther@suse.de>

	PR middle-end/83713
	* convert.c (do_narrow): Properly guard TYPE_OVERFLOW_WRAPS checks.

	* g++.dg/torture/pr83713.C: New testcase.

From-SVN: r256341

gcc/ChangeLog

 2018-01-08  Richard Biener  <rguenther@suse.de>
 
+	PR middle-end/83713
+	* convert.c (do_narrow): Properly guard TYPE_OVERFLOW_WRAPS checks.
+
+2018-01-08  Richard Biener  <rguenther@suse.de>
+
 	PR tree-optimization/83685
 	* tree-ssa-pre.c (create_expression_by_pieces): Do not insert
 	references to abnormals.

gcc/convert.c

@@ -471,8 +471,10 @@ do_narrow (location_t loc,
 	     type in case the operation in outprec precision
 	     could overflow.  Otherwise, we would introduce
 	     signed-overflow undefinedness.  */
-	  || ((!TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0))
-	       || !TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg1)))
+	  || ((!(INTEGRAL_TYPE_P (TREE_TYPE (arg0))
+		 && TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0)))
+	       || !(INTEGRAL_TYPE_P (TREE_TYPE (arg1))
+		    && TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg1))))
 	      && ((TYPE_PRECISION (TREE_TYPE (arg0)) * 2u
 		   > outprec)
 		  || (TYPE_PRECISION (TREE_TYPE (arg1)) * 2u

gcc/testsuite/ChangeLog

+2018-01-08  Richard Biener  <rguenther@suse.de>
+
+	PR middle-end/83713
+	* g++.dg/torture/pr83713.C: New testcase.
+
 2018-01-08  Tom de Vries  <tom@codesourcery.com>
 
 	* gcc.dg/tree-ssa/ssa-dom-cse-2.c: Xfail scan for nvptx.

gcc/testsuite/g++.dg/torture/pr83713.C

+// { dg-do compile }
+
+class a
+{
+  char b;
+  void c ();
+};
+void
+a::c ()
+{
+  &b + ((long long) &b & 0);
+}