On Mon, 14 Jul 2014, Richard Biener wrote:
> On Fri, 11 Jul 2014, Jakub Jelinek wrote:
>
> > On Fri, Jul 11, 2014 at 03:36:15PM +0200, Richard Biener wrote:
> > > *************** c_strlen (tree src, int only_value)
> > > *** 606,612 ****
> > >
> > > /* If the offset is known to be out of bounds, warn, and call strlen
> > > at
> > > runtime. */
> > > ! if (offset < 0 || offset > max)
> > > {
> > > /* Suppress multiple warnings for propagated constant strings. */
> > > if (! TREE_NO_WARNING (src))
> > > --- 610,617 ----
> > >
> > > /* If the offset is known to be out of bounds, warn, and call strlen
> > > at
> > > runtime. */
> > > ! if (only_value != 2
> > > ! && (offset < 0 || offset > max))
> > > {
> > > /* Suppress multiple warnings for propagated constant strings. */
> > > if (! TREE_NO_WARNING (src))
> >
> > This looks wrong. I'd say you only want to disable the warning for
> > only_value != 2, but still return NULL_TREE, otherwise the strlen call will
> > be out of bounds in the compiler. So move only_value != 2 down to the
> > second if ?
>
> Hmm, yeah. Probably doesn't matter for this use but I'm testing the
> obvious fix.
Fixed like so, bootstrapped and tested on x86_64-unknown-linux-gnu.
Richard.
2014-07-14 Richard Biener <rguent...@suse.de>
* builtins.c (c_strlen): Make only_value == 2 really only
affect warning generation.
Index: gcc/builtins.c
===================================================================
--- gcc/builtins.c (revision 212513)
+++ gcc/builtins.c (working copy)
@@ -610,11 +610,11 @@ c_strlen (tree src, int only_value)
/* If the offset is known to be out of bounds, warn, and call strlen at
runtime. */
- if (only_value != 2
- && (offset < 0 || offset > max))
+ if (offset < 0 || offset > max)
{
/* Suppress multiple warnings for propagated constant strings. */
- if (! TREE_NO_WARNING (src))
+ if (only_value != 2
+ && !TREE_NO_WARNING (src))
{
warning_at (loc, 0, "offset outside bounds of constant string");
TREE_NO_WARNING (src) = 1;
