[Bug libstdc++/83538] std::match_results C++14 conformance issue: reference != value_type&

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83538

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
This was changed by https://wg21.link/lwg2306