https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108178
--- Comment #7 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jonathan Wakely <r...@gcc.gnu.org>: https://gcc.gnu.org/g:07a0e108247f23fcb919c61595adae143f1ea02a commit r14-1570-g07a0e108247f23fcb919c61595adae143f1ea02a Author: Jonathan Wakely <jwak...@redhat.com> Date: Tue Mar 21 12:29:08 2023 +0000 libstdc++: Make std::filesystem::copy_file work for procfs [PR108178] The size reported by stat is always zero for some special files such as those under /proc, which means the current copy_file implementation thinks there is nothing to copy. Instead of trusting the stat value, try to read a character from a streambuf and check for EOF. libstdc++-v3/ChangeLog: PR libstdc++/108178 * src/filesystem/ops-common.h (do_copy_file): Check for empty files by trying to read a character. * testsuite/27_io/filesystem/operations/copy_file_108178.cc: New test.
