Fix IPA crash in libgccjit

gcc/ChangeLog:
	* ipa-cp.c (ipcp_driver): Set edge_clone_summaries to NULL after
	deleting it.
	* ipa-reference.c (ipa_reference_c_finalize): Delete
	ipa_ref_opt_sum_summaries and set it to NULL.

From-SVN: r261846

gcc/ChangeLog

+2018-06-21  David Malcolm  <dmalcolm@redhat.com>
+
+	* ipa-cp.c (ipcp_driver): Set edge_clone_summaries to NULL after
+	deleting it.
+	* ipa-reference.c (ipa_reference_c_finalize): Delete
+	ipa_ref_opt_sum_summaries and set it to NULL.
+
 2018-06-21  Tom de Vries  <tdevries@suse.de>
 
 	PR tree-optimization/85859

gcc/ipa-cp.c

@@ -5089,6 +5089,7 @@ ipcp_driver (void)
   /* Free all IPCP structures.  */
   free_toporder_info (&topo);
   delete edge_clone_summaries;
+  edge_clone_summaries = NULL;
   ipa_free_all_structures_after_ipa_cp ();
   if (dump_file)
     fprintf (dump_file, "\nIPA constant propagation end\n");

gcc/ipa-reference.c

@@ -1230,6 +1230,12 @@ make_pass_ipa_reference (gcc::context *ctxt)
 void
 ipa_reference_c_finalize (void)
 {
+  if (ipa_ref_opt_sum_summaries != NULL)
+    {
+      delete ipa_ref_opt_sum_summaries;
+      ipa_ref_opt_sum_summaries = NULL;
+    }
+
   if (ipa_init_p)
     {
       bitmap_obstack_release (&optimization_summary_obstack);