Re: [committed] libstdc++: Do not check exception at compile-time for mdspan::at for cow string.

[Jonathan Wakely]

On Tue, 24 Feb 2026 at 17:20, Tomasz Kaminski <tkami...@redhat.com> wrote:
>
>
>
> On Tue, Feb 24, 2026 at 6:13 PM Jonathan Wakely <jwak...@redhat.com> wrote:
>>
>> On Tue, 24 Feb 2026 at 17:07, Tomasz Kamiński <tkami...@redhat.com> wrote:
>> >
>> > Do not test the exception at compile time if _GLIBCXX_USE_CXX11_ABI
>> > is not set, i.e. standard exceptions types are not supported.
>> >
>> > libstdc++-v3/ChangeLog:
>> >
>> >         * testsuite/23_containers/mdspan/at.cc: Updated test.
>> > ---
>> > Tested on x86_64-linux. Pushed to trunk.
>> >
>> >  libstdc++-v3/testsuite/23_containers/mdspan/at.cc | 6 ++++++
>> >  1 file changed, 6 insertions(+)
>> >
>> > diff --git a/libstdc++-v3/testsuite/23_containers/mdspan/at.cc 
>> > b/libstdc++-v3/testsuite/23_containers/mdspan/at.cc
>> > index 4e659f57275..d9edce464ad 100644
>> > --- a/libstdc++-v3/testsuite/23_containers/mdspan/at.cc
>> > +++ b/libstdc++-v3/testsuite/23_containers/mdspan/at.cc
>> > @@ -89,6 +89,12 @@ template<typename Int, bool ValidForPacks, bool 
>> > ValidForArrays>
>> >        }
>> >      };
>> >
>> > +#if !_GLIBCXX_USE_CXX11_ABI
>>
>> Would  __cpp_lib_constexpr_exceptions be more precise, and make it
>> clearer exactly why we need to return early?
>
> Yes, that make sense, I have updated that to:
> -#if !_GLIBCXX_USE_CXX11_ABI
> +#if !__cpp_lib_constexpr_exceptions
>
> And will post that on master. I have already pushed that, so will push
> second change.

Thanks