Re: [PATCH] testsuite: Fix up gcc.dg/torture/bitint-100.c test [PR124948]

On Tue, Aug 4, 2026 at 8:54=E2=80=AFAM Jakub Jelinek <[email protected]> wro=
te:
>
> On Mon, Aug 03, 2026 at 01:56:35PM +0200, Torbjorn SVENSSON wrote:
> > On 2026-08-03 13:54, Jakub Jelinek wrote:
> > > On Mon, Aug 03, 2026 at 01:50:18PM +0200, Torbjorn SVENSSON wrote:
> > > > This change introduces new failures for arm-none-eabi using thumb/a=
rch=3Darmv6s-m/cpu=3Dcortex-m0/float-abi=3Dsoft/fpu=3Dauto.
> > > >
> > > > Testing torture/bitint-100.c,   -O0
> > > > doing compile
> > > > Executing on host: /build/install-native/bin/arm-none-eabi-gcc  /bu=
ild/gcc_src/gcc/testsuite/gcc.dg/torture/bitint-100.c  -mthumb -march=3Darm=
v6s-m -mcpu=3Dcortex-m0 -mfloat-abi=3Dsoft -mfpu=3Dauto   -dumpbase "" -fdi=
agnostics-plain-output    -O0  -std=3Dc23 -pedantic-errors      --specs=3Dr=
dimon.specs -Wl,--start-group -lc -lm -Wl,--end-group --specs=3Dnosys.specs=
 -Wl,--allow-multiple-definition -Wl,-u,_isatty,-u,_fstat  -Wl,-wrap,exit -=
Wl,-wrap,_exit -Wl,-wrap,main -Wl,-wrap,abort -Wl,gcc_tg.o -lm -T qemu.ld -=
o ./bitint-100.exe    (timeout =3D 800)
> > > > spawn -ignore SIGHUP /build/install-native/bin/arm-none-eabi-gcc /b=
uild/gcc_src/gcc/testsuite/gcc.dg/torture/bitint-100.c -mthumb -march=3Darm=
v6s-m -mcpu=3Dcortex-m0 -mfloat-abi=3Dsoft -mfpu=3Dauto -dumpbase  -fdiagno=
stics-plain-output -O0 -std=3Dc23 -pedantic-errors --specs=3Drdimon.specs -=
Wl,--start-group -lc -lm -Wl,--end-group --specs=3Dnosys.specs -Wl,--allow-=
multiple-definition -Wl,-u,_isatty,-u,_fstat -Wl,-wrap,exit -Wl,-wrap,_exit=
 -Wl,-wrap,main -Wl,-wrap,abort -Wl,gcc_tg.o -lm -T qemu.ld -o ./bitint-100=
.exe
> > > > pid is 1478576 -1478576
> > > > /build/install-native/arm-none-eabi/bin/ld: /tmp/ccgSaSgH.o: in fun=
ction `f1':
> > > > bitint-100.c:(.text+0x5a): undefined reference to `__atomic_compare=
_exchange_4'
> > > > /build/install-native/arm-none-eabi/bin/ld: (__atomic_compare_excha=
nge_4): Unknown destination type (ARM/Thumb) in /tmp/ccgSaSgH.o
> > > > bitint-100.c:(.text+0x5a): dangerous relocation: unsupported reloca=
tion
> > > > /build/install-native/arm-none-eabi/bin/ld: /tmp/ccgSaSgH.o: in fun=
ction `f2':
> > > > bitint-100.c:(.text+0xa4): undefined reference to `__atomic_compare=
_exchange_4'
> > > > /build/install-native/arm-none-eabi/bin/ld: (__atomic_compare_excha=
nge_4): Unknown destination type (ARM/Thumb) in /tmp/ccgSaSgH.o
> > > > bitint-100.c:(.text+0xa4): dangerous relocation: unsupported reloca=
tion
> > > > ...
> > > > collect2: error: ld returned 1 exit status
> > > >   status 1
> > > > compiler exited with status 1
> > > > FAIL: gcc.dg/torture/bitint-100.c   -O0  (test for excess errors)
> > > >
> > > > Same failure exist on both trunk and releases/gcc-16.
> > >
> > > I thought gcc has been changed to add -latomic_asneeded by default.
> > > Or is this because the linker doesn't support it in this configuratio=
n?
> > To my knowledge, there is no atomic support for armv6s-m, but I can be =
wrong.
>
> Most of the tests that are dg-do run and use atomics on int/long use
> sync_int_long effective target.  Atomics on _BitInt(17), i.e. something
> on all currently supported targets larger than short, probably need to be
> treated the same.
>
> Tested on x86_64-linux, ok for trunk?

Ok.


>
> 2026-08-04  Jakub Jelinek  <[email protected]>
>
>         PR target/124948
>         * gcc.dg/torture/bitint-100.c: Require also sync_int_long effecti=
ve
>         target.
>
> --- gcc/testsuite/gcc.dg/torture/bitint-100.c.jj        2026-07-14 10:43:=
39.057947557 +0200
> +++ gcc/testsuite/gcc.dg/torture/bitint-100.c   2026-08-04 17:43:31.93719=
3354 +0200
> @@ -1,5 +1,5 @@
>  /* PR target/124948 */
> -/* { dg-do run { target bitint } } */
> +/* { dg-do run { target { bitint && sync_int_long } } } */
>  /* { dg-options "-std=3Dc23 -pedantic-errors" } */
>  /* { dg-skip-if "" { ! run_expensive_tests }  { "*" } { "-O0" "-O2" } } =
*/
>  /* { dg-skip-if "" { ! run_expensive_tests } { "-flto" } { "" } } */
>
>
>         Jakub
>