[Bug libstdc++/104602] std::source_location::current uses cast from void*

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104602

--- Comment #9 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Hmm, we probably want to backport this, otherwise this check will start to pass
for future clang versions:
#if __cplusplus > 201703L && __has_builtin(__builtin_source_location)
but the code will be invalid.