https://gcc.gnu.org/bugzilla/show_bug.cgi?id=30929
Manuel López-Ibáñez <manu at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |manu at gcc dot gnu.org --- Comment #7 from Manuel López-Ibáñez <manu at gcc dot gnu.org> --- An update given the new diagnostics machinery: * -Werror works as expected (comment #2) * -pedantic-errors (-Werror=pedantic) should give errors for anything marked with -Wpedantic such as: gfc_warning (OPT_Wpedantic, "Extension: backslash character at %C"); However, Fortran does not seem to use OPT_Wpedantic. You could use LangEnabledBy to enable with it whatever option you wish.