On Mon, 14 Dec 2020, 06:51 François Dumont via Libstdc++, < libstd...@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. > > > > > >> The other test is failing because of some cleanup in headers which > >> makes <memory> include necessary. > >> > >>    libstdc++: Fix several _GLIBCXX_DEBUG tests > >> > >>    libstdc++-v3/ChangeLog: > >> > >>            * > >> testsuite/23_containers/array/debug/back2_neg.cc: target c++14 > >> because assertion > >>            for constexpr is disabled in C++11. > >>            * > >> testsuite/23_containers/array/debug/front2_neg.cc: Likewise. > >>            * > >> testsuite/23_containers/array/debug/square_brackets_operator2_neg.cc: > >> Likewise. > >>            * > >> testsuite/23_containers/vector/debug/multithreaded_swap.cc: Include > >> <memory> > >>            for shared_ptr. > >> > >> Ok to commit ? > > > > Yes, thanks. > > > > > >