On 14/12/20 22:36 +0100, François Dumont wrote:
On 14/12/20 11:08 am, Jonathan Wakely wrote:
On Mon, 14 Dec 2020, 06:51 François Dumont via Libstdc++,
<libstd...@gcc.gnu.org <mailto:libstdc%2b...@gcc.gnu.org>> wrote:
On 13/12/20 11:17 pm, Jonathan Wakely wrote:
> On 13/12/20 15:52 +0100, François Dumont via Libstdc++ wrote:
>> Some tests are XPASS because array assertions have been
disabled for
>> a good reason in C++11.
>>
>> I wonder if the respective non-constexpr _GLIBCXX_ASSERTION checks
>> shouldn't target C++14 too. At the moment they are failing as
>> expected but because of an Undefined Behavior no ?
>
> Hmm, maybe my "fix" for the bug was too hasty, and I should have
done
> this instead:
>
> --- a/libstdc++-v3/include/bits/c++config
> +++ b/libstdc++-v3/include/bits/c++config
> @@ -684,7 +684,7 @@ namespace std
>
> #undef _GLIBCXX_HAS_BUILTIN
>
> -#if _GLIBCXX_HAVE_BUILTIN_IS_CONSTANT_EVALUATED
> +#if _GLIBCXX_HAVE_BUILTIN_IS_CONSTANT_EVALUATED && __cplusplus >=
> 201402L
> # define __glibcxx_assert_1(_Condition) \
> if (__builtin_is_constant_evaluated()) \
> { \
>
> That would allow us to keep the std::array runtime assertions for
> C++11, and only disable them in constexpr contexts.
I already tried to restore this check in C++11 runtime without
success
but I didn't try this approach.
I'll have a try but C++11 forces constexpr to be just a return
statement
so I fear that it won't appreciate the additional assertion.
Ah yes, we'd need something like Daniel suggested, and it's not
worth it just for C++11.
Just limiting the tests to c++14 is fine.
Attached patch committed then.
Thanks.
