https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84559
--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
That said, we accept:
void foo(int i)
{
constexpr char x[i] = {1, 2, 3};
}
clang++ rejects both: error: constexpr variable cannot have non-literal type
'char const[i]'
