https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83306
--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> --- Author: redi Date: Wed Nov 28 17:07:22 2018 New Revision: 266569 URL: https://gcc.gnu.org/viewcvs?rev=266569&root=gcc&view=rev Log: Fix undefined references in libstdc++fs.a The recent patch for PR 83306 removed the fs_err_concat functions that were used by the experimental::filesystem::filesystem_error class as well. This fixes it by doing the string generation directly in filesystem_error::_M_gen_what() instead of using the removed function. PR libstdc++/83306 * src/filesystem/path.cc (filesystem_error::_M_gen_what()): Create string directly, instead of calling fs_err_concat. Modified: trunk/libstdc++-v3/ChangeLog trunk/libstdc++-v3/src/filesystem/path.cc