Am Montag, dem 27.11.2023 um 16:54 +0100 schrieb Martin Uecker:
> Am Montag, dem 27.11.2023 um 08:36 -0700 schrieb Jeff Law:
> >
> > On 11/23/23 10:05, Hans-Peter Nilsson wrote:
> > > > From: Hans-Peter Nilsson <h...@axis.com>
> > > > Date: Thu, 16 Nov 2023 05:24:06 +0100
> > > >
> > > > > From: Martin Uecker <uec...@tugraz.at>
> > > > > Date: Tue, 07 Nov 2023 06:56:25 +0100
> > > >
> > > > > Am Montag, dem 06.11.2023 um 21:01 -0700 schrieb Jeff Law:
> > > > > >
> > > > > > On 11/6/23 20:58, Hans-Peter Nilsson wrote:
> > > > > > > This patch caused a testsuite regression: there's now an
> > > > > > > "excess error" failure for gcc.dg/Wnonnull-4.c for 32-bit
> > > > > > > targets (and 64-bit targets testing with a "-m32" option)
> > > > > > > after your r14-5115-g6e9ee44d96e5. It's logged as PR112419.
> > > > > > It caused failures for just about every target ;( Presumably it
> > > > > > worked
> > > > > > on x86_64...
> > > > >
> > > > > I do not think this is a true regression
> > > > > just a problem with the test on 32-bit which somehow surfaced
> > > > > due to the change.
> > > > >
> > > > > The excess error is:
> > > > >
> > > > > FAIL: gcc.dg/Wnonnull-4.c (test for excess errors)
> > > > > Excess errors:
> > > > > /home/tcwg-buildslave/workspace/tcwg_gnu_6/abe/snapshots/gcc.git~master/gcc/testsuite/gcc.dg/Wnonnull-4.c:144:3:
> > > > > warning: 'fda_n_5' specified size 4294967256 exceeds maximum object
> > > > > size
> > > > > 2147483647 [-Wstringop-overflow=]
> > > > >
> > > > > I think the warning was suppressed before due to the other (nonnull)
> > > > > warning which I removed in this case.
> > > > >
> > > > > I think the simple fix might be to to turn off -Wstringop-overflow.
> > > >
> > > > No, that trigs many of the dg-warnings that are tested.
> > > >
> > > > (I didn't pay attention to the actual warning messages and
> > > > tried to pursue that at first.)
> > > >
> > > > Maybe think it's best to actually expect the warning, like
> > > > so.
> > > >
> > > > Maintainers of 16-bit targets will have to address their
> > > > concerns separately. For example, they may choose to not
> > > > run the test at all.
> > > >
> > > > Ok to commit?
> > > >
> > > > Subject: [PATCH] gcc.dg/Wnonnull-4.c: Handle new overflow warning for
> > > > 32-bit targets [PR112419]
> > > >
> > > > PR testsuite/112419
> > > > * gcc.dg/Wnonnull-4.c (test_fda_n_5): Expect warning for
> > > > exceeding
> > > > maximum object size for 32-bit targets.
> > > > ---
> > > > gcc/testsuite/gcc.dg/Wnonnull-4.c | 1 +
> > > > 1 file changed, 1 insertion(+)
> > > >
> > > > diff --git a/gcc/testsuite/gcc.dg/Wnonnull-4.c
> > > > b/gcc/testsuite/gcc.dg/Wnonnull-4.c
> > > > index 1f14fbba45df..d63e76da70a2 100644
> > > > --- a/gcc/testsuite/gcc.dg/Wnonnull-4.c
> > > > +++ b/gcc/testsuite/gcc.dg/Wnonnull-4.c
> > > > @@ -142,6 +142,7 @@ void test_fda_n_5 (int r_m1)
> > > > T ( 1); // { dg-bogus "argument 2 of variable length
> > > > array 'double\\\[n]\\\[5]' is null but the corresponding bound argument
> > > > 1 value is 1" }
> > > > T ( 9); // { dg-bogus "argument 2 of variable length
> > > > array 'double\\\[n]\\\[5]' is null but the corresponding bound argument
> > > > 1 value is 9" }
> > > > T (max); // { dg-bogus "argument 2 of variable length
> > > > array 'double\\\[n]\\\[5]' is null but the corresponding bound argument
> > > > 1 value is \\d+" }
> > > > +// { dg-warning "size 4294967256 exceeds maximum object size" "" {
> > > > target ilp32 } .-1 }
> > > > }
> > Unfortunately I think we need to go back to the original issue that
> > Martin (I think) dismissed.
> >
> > Specifically, this is a regression. It's very clear that prior to the
> > patch in question there was no diagnostic about the size of the
> > requested memory allocation and after the patch in question we get the
> > "exceeds maximum object size" diagnostic.
> >
> > Now one explanation could be that the diagnostic is warranted and it was
> > a bug that the diagnostic hadn't been emitted prior to Martin's patch.
> > In this case some kind of dg-blah is warranted, but I don't think anyone
> > has made this argument.
> >
> I believe the warning is correct but was suppressed before.
>
>
> My plan was to split up the test case in one which is for
> -Wstringop-overflow and one which is for -Wnonnull and then
> one could turn off the -Wstringop-overflow for the tests
> which are actually for -Wnonnull. But adding the dg-blah
> would certainly be simpler.
Specifically, also with 13.2 if you suppress the warning which
I removed with -Wno-nonnull you will get the otherwise hidden
-Wstringop-overflow warning with -m32:
See here: https://godbolt.org/z/ev5GhMonq
The warning also seems correct to me, so I suggest to accept
the proposed patch.
Martin
