[Bug libstdc++/106296] Consider using fsync or fdatasync in filesystem::copy_file

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106296

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
However, see https://github.com/boostorg/filesystem/issues/186