Re: [committed 03/22] arm: testsuite: avoid hard-float ABI incompatibility with -march

[Christophe Lyon <christophe.lyon@linaro.org>]

Hi Richard,

On Mon, 13 Nov 2023 at 15:28, Richard Earnshaw <rearnsha@arm.com> wrote:
>
>
> A number of tests in the gcc testsuite, especially for arm-specific
> targets, add various flags to control the architecture.  These run
> into problems when the compiler is configured with -mfpu=auto if the
> new architecture lacks an architectural feature that implies we have
> floating-point instructions.
>
> The testsuite makes this worse as it falls foul of this requirement in
> the base architecture strings provided by target-supports.exp.
>
> To fix this we add "+fp", or something equivalent to this, to all the
> base architecture specifications.  The feature will be ignored if the
> float ABI is set to soft.
>
> gcc/testsuite:
>
>         * lib/target-supports.exp (check_effective_target_arm_arch_FUNC_ok):
>         Add base FPU specifications to all architectures that can support
>         one.
> ---
>  gcc/testsuite/lib/target-supports.exp | 50 +++++++++++++--------------
>  1 file changed, 25 insertions(+), 25 deletions(-)
>

Our CI has detected some regressions with this patch, in particular
when testing for cortex-m55:

with -mthumb/-march=armv8.1-m.main+mve.fp+fp.dp/-mtune=cortex-m55/-mfloat-abi=hard/-mfpu=auto
and GCC configured with --disable-multilib --with-mode=thumb
--with-arch=armv8.1-m.main+mve.fp+fp.dp --with-float=hard

you can see our logs here:
https://ci.linaro.org/job/tcwg_gnu_embed_check_gcc--master-thumb_m55_hard_eabi-build/209/artifact/artifacts/00-sumfiles/

Thanks,

Christophe