[Bug libstdc++/65352] array::begin()/end() etc. forms a null reference and breaks on clang+ubsan

[rs2740 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65352

--- Comment #3 from TC <rs2740 at gmail dot com> ---
Depends on how http://cplusplus.github.io/LWG/lwg-active.html#2443 comes out in
LEWG, it might be a good idea to go with a solution that maintains the
`constexpr`-ness so that it doesn't have to be redone again if the committee
ends up making, say, begin() and end() constexpr.

Of course, you are a lot more familiar with the committee's workings than I do
:)