re PR middle-end/65233 (ICE (segfault) on arm-linux-gnueabihf and aarch64-linux-gnu)

	PR middle-end/65233
	* ipa-polymorphic-call.c (walk_ssa_copies): Handle empty PHIs.

From-SVN: r221097

gcc/ChangeLog

+2015-03-01  Aldy Hernandez  <aldyh@redhat.com>
+
+	PR middle-end/65233
+	* ipa-polymorphic-call.c (walk_ssa_copies): Handle empty PHIs.
+
 2015-02-28  Jan Hubicka  <hubicka@ucw.cz>
 
 	* ipa-icf.c: Include stor-layout.h

gcc/ipa-polymorphic-call.c

@@ -835,7 +835,10 @@ walk_ssa_copies (tree op, hash_set<tree> **global_visited = NULL)
 	{
 	  gimple phi = SSA_NAME_DEF_STMT (op);
 
-	  if (gimple_phi_num_args (phi) > 2)
+	  if (gimple_phi_num_args (phi) > 2
+	      /* We can be called while cleaning up the CFG and can
+		 have empty PHIs about to be removed.  */
+	      || gimple_phi_num_args (phi) == 0)
 	    goto done;
 	  if (gimple_phi_num_args (phi) == 1)
 	    op = gimple_phi_arg_def (phi, 0);