Re: C++ PATCH for c++/48446 (ICE with VLA)

[Jason Merrill]

I noticed a minor tweak I could make to speed this up and figure I might 
as well, even though it shouldn't be a significant component of compile 
time.

Tested x86_64-pc-linux-gnu, applying to trunk and 4.6.
commit 4c3e6de3e988799dac490b6eb2b762674b5bb9f8
Author: Jason Merrill <ja...@redhat.com>
Date:   Thu May 5 17:57:50 2011 -0400
        * decl.c (stabilize_save_expr_r): Set *walk_subtrees as
        appropriate.

diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index c5184e0..b5d4cc2 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -7615,8 +7615,9 @@ stabilize_save_expr_r (tree *expr_p, int *walk_subtrees, 
void *data)
       cp_walk_tree (&op, stabilize_save_expr_r, data, pset);
       if (TREE_SIDE_EFFECTS (op))
        TREE_OPERAND (expr, 0) = get_temp_regvar (TREE_TYPE (op), op);
+      *walk_subtrees = 0;
     }
-  else if (!EXPR_P (expr))
+  else if (!EXPR_P (expr) || !TREE_SIDE_EFFECTS (expr))
     *walk_subtrees = 0;
   return NULL;
 }