This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
[PATCH] Fix PR50472
- From: Richard Guenther <rguenther at suse dot de>
- To: gcc-patches at gcc dot gnu dot org
- Date: Mon, 26 Sep 2011 14:54:51 +0200 (CEST)
- Subject: [PATCH] Fix PR50472
Bootstrapped and tested on x86_64-unknown-linux-gnu, applied.
Richard.
2011-09-26 Richard Guenther <rguenther@suse.de>
PR tree-optimization/50472
* gimple-fold.c (fold_const_aggregate_ref_1): Do not fold
volatile references.
* gcc.dg/torture/pr50472.c: New testcase.
Index: gcc/gimple-fold.c
===================================================================
--- gcc/gimple-fold.c (revision 179185)
+++ gcc/gimple-fold.c (working copy)
@@ -2919,6 +2919,9 @@ fold_const_aggregate_ref_1 (tree t, tree
HOST_WIDE_INT offset, size, max_size;
tree tem;
+ if (TREE_THIS_VOLATILE (t))
+ return NULL_TREE;
+
if (TREE_CODE_CLASS (TREE_CODE (t)) == tcc_declaration)
return get_symbol_constant_value (t);
Index: gcc/testsuite/gcc.dg/torture/pr50472.c
===================================================================
--- gcc/testsuite/gcc.dg/torture/pr50472.c (revision 0)
+++ gcc/testsuite/gcc.dg/torture/pr50472.c (revision 0)
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-fdump-tree-optimized" } */
+
+static const unsigned int foo = 1;
+unsigned int test( void )
+{
+ const volatile unsigned int *bar = &foo;
+ return ( *bar );
+}
+
+/* { dg-final { scan-tree-dump-not "return 1" "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */