Re: [v2 of PATCH 15/14] Use fold_for_warn in get_atomic_generic_size

[Jason Merrill]

On Tue, Dec 19, 2017 at 7:53 PM, David Malcolm <dmalc...@redhat.com> wrote:
> On Tue, 2017-12-19 at 15:35 -0500, Jason Merrill wrote:
>> On Sat, Dec 16, 2017 at 8:12 PM, David Malcolm <dmalc...@redhat.com>
>> wrote:
>> > I rebased the v2 patchkit; here's an extra patch to fix an issue
>> > with it uncovered by a recently-added testcase (in r254990).
>> >
>> > With the patch kit, but without this patch, g++'s
>> >   c-c++-common/pr83059.c
>> > fails to emit the "invalid memory model argument 6" warning.
>> >
>> > Successfully bootstrapped&regrtested on x86_64-pc-linux-gnu, as
>> > part of the kit.
>> >
>> > Is this OK for trunk, assuming the rest of the kit is approved?
>> >
>> > gcc/c-family/ChangeLog:
>> >         * c-common.c (get_atomic_generic_size): Call fold_for_warn
>> > on the
>> >         params before checking for INTEGER_CST.
>> > ---
>> >  gcc/c-family/c-common.c | 2 +-
>> >  1 file changed, 1 insertion(+), 1 deletion(-)
>> >
>> > diff --git a/gcc/c-family/c-common.c b/gcc/c-family/c-common.c
>> > index 3438b87..ab03b7d 100644
>> > --- a/gcc/c-family/c-common.c
>> > +++ b/gcc/c-family/c-common.c
>> > @@ -6720,7 +6720,7 @@ get_atomic_generic_size (location_t loc, tree
>> > function,
>> >    /* Check memory model parameters for validity.  */
>> >    for (x = n_param - n_model ; x < n_param; x++)
>> >      {
>> > -      tree p = (*params)[x];
>> > +      tree p = fold_for_warn ((*params)[x]);
>> >        if (TREE_CODE (p) == INTEGER_CST)
>> >          {
>> >           /* memmodel_base masks the low 16 bits, thus ignore any
>> > bits above
>>
>> Let's check the error case before we call fold_for_warn.
>>
>> Jason
>
> Do you mean like this?  (bootstrapped; regrtest in progress)

Ah, no, sorry I wasn't clear.  I meant to reorder the if/else there,
so we check for INTEGER_TYPE first and potentially give an error, then
fold, and then potentially warn.

Jason