[Bug c++/105584] libcxx needs using_if_exist attribute

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105584

--- Comment #6 from Sam James <sjames at gcc dot gnu.org> ---
I'm not sure that's related, at least the quoted lines don't mention
_LIBCPP_USING_IF_EXISTS.