lto-streamer-out.c (cmp_symbol_files): Watch for overflow.

	* lto-streamer-out.c (cmp_symbol_files): Watch for overflow.

From-SVN: r277348

gcc/ChangeLog

 2019-10-23  Jan Hubicka  <hubicka@ucw.cz>
 
+	* lto-streamer-out.c (cmp_symbol_files): Watch for overflow.
+
+2019-10-23  Jan Hubicka  <hubicka@ucw.cz>
+
 	* ipa-reference.c (varpool_removal_hook, ipa_reference_c_finalize): Fix
 	previous patch.
 

gcc/lto-streamer-out.c

@@ -2447,7 +2447,12 @@ cmp_symbol_files (const void *pn1, const void *pn2)
 
   /* Order within static library.  */
   if (n1->lto_file_data && n1->lto_file_data->id != n2->lto_file_data->id)
-    return n1->lto_file_data->id - n2->lto_file_data->id;
+    {
+      if (n1->lto_file_data->id > n2->lto_file_data->id)
+	return 1;
+      if (n1->lto_file_data->id < n2->lto_file_data->id)
+	return -1;
+    }
 
   /* And finaly order by the definition order.  */
   return n1->order - n2->order;