[Bug libstdc++/100475] semiregular-box's constructor uses wrong list-initialization

[hewillk at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100475

--- Comment #3 from 康桓瑋 <hewillk at gmail dot com> ---
Also, the operator->() simply uses operator& instead of std::__addressof.

https://godbolt.org/z/zfGnEoePG