re PR middle-end/78047 (Chromium apparently gets miscompiled)

2016-11-02  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/78047
	* tree-ssa-structalias.c (push_fields_onto_fieldstack): Initialize
	fake field at offset zero conservatively regarding to may_have_pointers.

From-SVN: r241775

gcc/ChangeLog

 2016-11-02  Richard Biener  <rguenther@suse.de>
 
+	PR tree-optimization/78047
+	* tree-ssa-structalias.c (push_fields_onto_fieldstack): Initialize
+	fake field at offset zero conservatively regarding to may_have_pointers.
+
+2016-11-02  Richard Biener  <rguenther@suse.de>
+
 	* tree-vrp.c (evrp_dom_walker::before_dom_children): Call
 	infer_value_range on stmt ops and update value-ranges.
 	Dump visited stmts and blocks.

gcc/tree-ssa-structalias.c

@@ -5566,7 +5566,7 @@ push_fields_onto_fieldstack (tree type, vec<fieldoff_s> *fieldstack,
 		&& offset + foff != 0)
 	      {
 		fieldoff_s e
-		  = {0, offset + foff, false, false, false, false, NULL_TREE};
+		  = {0, offset + foff, false, false, true, false, NULL_TREE};
 		pair = fieldstack->safe_push (e);
 	      }