[Bug c++/105233] Incorrect "alignment not an integer constant" error in alignas with template parameter dependent argument

[jakub at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105233

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
      // If the shift exponent equals _Nd then the correct result is not
      // representable as a value of _Tp, and so the result is undefined.
      // Want that undefined behaviour to be detected in constant expressions,
      // by UBSan, and by debug assertions.
      if (!std::__is_constant_evaluated())
        {
          __glibcxx_assert( __shift_exponent != __int_traits<_Tp>::__digits );
        }
is what is in the header.