* 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.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@120837 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 6 insertions, 1 deletions

diff --git a/gcc/tree-ssanames.c b/gcc/tree-ssanames.c
index d9ab940fa90..07b83f831af 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;