From: Jan Hubicka <jh@suse.cz>
Date: Tue, 16 Jan 2007 23:42:06 +0000 (+0100)
Subject: tree-ssanames.c (release_dead_ssa_names): Instead of ggc_freeing the names...
X-Git-Tag: releases/gcc-4.3.0~7463
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=109c8d3934b3748a2fdb061c9a250b30b54fdf5b;p=thirdparty%2Fgcc.git

tree-ssanames.c (release_dead_ssa_names): Instead of ggc_freeing the names...

	* tree-ssanames.c (release_dead_ssa_names): Instead of ggc_freeing
	the names, just unlink the chain so we don't crash on dangling pointers
	to dead SSA names.

From-SVN: r120837
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 7d44816fc9e4..a8e0c18d8348 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2007-01-16  Jan Hubicka  <jh@suse.cz>
+
+	* tree-ssanames.c (release_dead_ssa_names): Instead of ggc_freeing
+	the names, just unlink the chain so we don't crash on dangling pointers
+	to dead SSA names.
+
 2007-01-16  Jan Hubicka  <jh@suse.cz>
 
 	* cgraph.h (cgraph_decide_inlining_incrementally): Kill.
diff --git a/gcc/tree-ssanames.c b/gcc/tree-ssanames.c
index d9ab940fa90a..07b83f831afc 100644
--- a/gcc/tree-ssanames.c
+++ b/gcc/tree-ssanames.c
@@ -325,7 +325,12 @@ release_dead_ssa_names (void)
   for (t = FREE_SSANAMES (cfun); t; t = next)
     {
       next = TREE_CHAIN (t);
-      ggc_free (t);
+      /* Dangling pointers might make GGC to still see dead SSA names, so it is
+ 	 important to unlink the list and avoid GGC from seeing all subsequent
+	 SSA names.  In longer run we want to have all dangling pointers here
+	 removed (since they usually go trhough dead statements that consume
+	 considerable amounts of memory).  */
+      TREE_CHAIN (t) = NULL_TREE;
       n++;
     }
   FREE_SSANAMES (cfun) = NULL;