https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79049
David Binderman <dcb314 at hotmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |dcb314 at hotmail dot com --- Comment #2 from David Binderman <dcb314 at hotmail dot com> --- There are two packages in Fedora where this warning occurs when compiled by clang: $ fgrep warning: fedora/pass268/202201*/*.out | fgrep Wunknown-escape-sequence fedora/pass268/20220107/nco.spec.out:nco_lst_utl.c:38:47: warning: unknown escape sequence '\.' [-Wunknown-escape-sequence] fedora/pass268/20220110/safecopy.spec.out:safecopy.c:263:56: warning: unknown escape sequence '\-' [-Wunknown-escape-sequence] $ gcc doesn't seem to generate the warning.