Fix ipa.c dumping ICE

[Jan Hubicka]

Hi,
this patch fixes ICE on missing call_stmt during WPA.
Index: ChangeLog
===================================================================
--- ChangeLog   (revision 215791)
+++ ChangeLog   (working copy)
@@ -1,5 +1,10 @@
 2014-10-01  Jan HUbicka  <hubi...@ucw.cz>
 
+       * ipa.c (walk_polymorphic_call_targets): Avoid ICE when
+       dumping during WPA.
+
+2014-10-01  Jan HUbicka  <hubi...@ucw.cz>
+
        * ipa-prop.c (ipa_modify_formal_parameters): Do not merge
        type variants.
 
Index: ipa.c
===================================================================
--- ipa.c       (revision 215658)
+++ ipa.c       (working copy)
@@ -198,7 +198,11 @@ walk_polymorphic_call_targets (hash_set<
 
          if (dump_enabled_p ())
             {
-             location_t locus = gimple_location (edge->call_stmt);
+             location_t locus;
+             if (edge->call_stmt)
+               locus = gimple_location (edge->call_stmt);
+             else
+               locus = UNKNOWN_LOCATION;
              dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, locus,
                                "devirtualizing call in %s/%i to %s/%i\n",
                                edge->caller->name (), edge->caller->order,