Reset global state ipa-icf.c:optimizer

gcc/
	* ipa-icf.c (ipa_icf_driver): Set optimizer to NULL when done.

From-SVN: r216561

gcc/ChangeLog

+2014-10-22  David Malcolm  <dmalcolm@redhat.com>
+
+	* ipa-icf.c (ipa_icf_driver): Set optimizer to NULL when done.
+
 2014-10-22  Andrew MacLeod  <amacleod@redhat.com>
 
 	* cfgbuild.h: New.  Add prototypes for cfgbuild.c.

gcc/ipa-icf.c

@@ -2320,6 +2320,7 @@ ipa_icf_driver (void)
   optimizer->unregister_hooks ();
 
   delete optimizer;
+  optimizer = NULL;
 
   return 0;
 }