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

2009-10-26  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: r153550

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e7c10ad..4b18b44 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,11 @@
 2009-10-26  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.
+
+2009-10-26  Richard Guenther  <rguenther@suse.de>
+
        * graphite-sese-to-poly.c (check_poly_representation): Fix
        compile without checking.
 

diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index e5f4a29..cc655df 100644 (file)
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -2825,7 +2825,7 @@ 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;
   HOST_WIDE_INT rhsunitoffset, rhsoffset;
 
@@ -2863,14 +2863,14 @@ 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
          /* If this varinfo represents a full variable just use it.  */
          && curr->is_full_var)
-       c->offset = 0;
-      else if (c->type == ADDRESSOF
+       c.offset = 0;
+      else if (c.type == ADDRESSOF
               /* If we do not know the offset add all subfields.  */
               && rhsoffset == UNKNOWN_OFFSET)
        {
@@ -2881,13 +2881,13 @@ get_constraint_for_ptr_offset (tree ptr, tree offset,
              c2.var = temp->id;
              c2.type = ADDRESSOF;
              c2.offset = 0;
-             if (c2.var != c->var)
+             if (c2.var != c.var)
                VEC_safe_push (ce_s, heap, *results, &c2);
              temp = temp->next;
            }
          while (temp);
        }
-      else if (c->type == ADDRESSOF)
+      else if (c.type == ADDRESSOF)
        {
          varinfo_t temp;
          unsigned HOST_WIDE_INT offset = curr->offset + rhsoffset;
@@ -2919,11 +2919,13 @@ 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
-       c->offset = rhsoffset;
+       c.offset = rhsoffset;
+
+      VEC_replace (ce_s, *results, j, &c);
     }
 }