From: Richard Guenther <rguenther@suse.de>
Date: Wed, 20 Jan 2010 13:07:41 +0000 (+0000)
Subject: re PR tree-optimization/41826 (invalid read in get_constraint_for_ptr_offset)
X-Git-Tag: releases/gcc-4.3.5~213
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=911222c233f5e56adfed2fc63f702caadcf3ef1d;p=thirdparty%2Fgcc.git

re PR tree-optimization/41826 (invalid read in get_constraint_for_ptr_offset)

2010-01-20  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/41826
	* tree-ssa-structalias.c (get_constraint_for_ptr_offset): Avoid
	access to re-allocated vector fields.

From-SVN: r156079
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index cecb2e42fcbe..2ba1f5d1bef0 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2010-01-20  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/41826
+	* tree-ssa-structalias.c (get_constraint_for_ptr_offset): Avoid
+	access to re-allocated vector fields.
+
 2010-01-18  Uros Bizjak  <ubizjak@gmail.com>
 
 	PR target/42774
diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index 97c4fb32c73c..cf91502e6102 100644
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -2657,7 +2657,7 @@ static void
 get_constraint_for_ptr_offset (tree ptr, tree offset,
 			       VEC (ce_s, heap) **results)
 {
-  struct constraint_expr *c;
+  struct constraint_expr c;
   unsigned int j, n;
   unsigned HOST_WIDE_INT rhsunitoffset, rhsoffset;
 
@@ -2708,13 +2708,13 @@ get_constraint_for_ptr_offset (tree ptr, tree offset,
   for (j = 0; j < n; j++)
     {
       varinfo_t curr;
-      c = VEC_index (ce_s, *results, j);
-      curr = get_varinfo (c->var);
+      c = *VEC_index (ce_s, *results, j);
+      curr = get_varinfo (c.var);
 
-      if (c->type == ADDRESSOF
+      if (c.type == ADDRESSOF
 	  && !curr->is_full_var)
 	{
-	  varinfo_t temp, curr = get_varinfo (c->var);
+	  varinfo_t temp, curr = get_varinfo (c.var);
 
 	  /* Search the sub-field which overlaps with the
 	     pointed-to offset.  As we deal with positive offsets
@@ -2750,15 +2750,17 @@ get_constraint_for_ptr_offset (tree ptr, tree offset,
 	      c2.offset = 0;
 	      VEC_safe_push (ce_s, heap, *results, &c2);
 	    }
-	  c->var = temp->id;
-	  c->offset = 0;
+	  c.var = temp->id;
+	  c.offset = 0;
 	}
-      else if (c->type == ADDRESSOF
+      else if (c.type == ADDRESSOF
 	       /* If this varinfo represents a full variable just use it.  */
 	       && curr->is_full_var)
-	c->offset = 0;
+	c.offset = 0;
       else
-	c->offset = rhsoffset;
+	c.offset = rhsoffset;
+
+      VEC_replace (ce_s, *results, j, &c);
     }
 }