[PATCH] libstdc++: Fix SFINAE for __is_intrinsic_type on ARM

[Jonathan Wakely]

On Wed, 24 May 2023 at 11:59, Matthias Kretz via Libstdc++ <
libstdc++@gcc.gnu.org> wrote:

> OK for master and all branches? (this issue only surfaced because of the
> new
> test)
>

OK.



>
> ------------ 8< -----------------
>
> On ARM NEON doesn't support double, so __is_intrinsic_type_v<double,
> whatever> should say false (instead of being ill-formed).
>
> Signed-off-by: Matthias Kretz <m.kretz@gsi.de>
>
> libstdc++-v3/ChangeLog:
>
>         PR libstdc++/109261
>         * include/experimental/bits/simd.h (__intrinsic_type):
>         Specialize __intrinsic_type<double, 8> and
>         __intrinsic_type<double, 16> in any case, but provide the member
>         type only with __aarch64__.
> ---
>  libstdc++-v3/include/experimental/bits/simd.h | 12 +++++++++---
>  1 file changed, 9 insertions(+), 3 deletions(-)
>
>
> --
> ──────────────────────────────────────────────────────────────────────────
>  Dr. Matthias Kretz                           https://mattkretz.github.io
>  GSI Helmholtz Centre for Heavy Ion Research               https://gsi.de
>  stdₓ::simd
> ──────────────────────────────────────────────────────────────────────────