In gcc/doc/invoke.texi all the cygwin/mingw specific target -m options aren't documented.
-- Summary: Missing documentation of cygwin and mingw target options Product: gcc Version: unknown Status: UNCONFIRMED Severity: normal Priority: P3 Component: target AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: ktietz at gcc dot gnu dot org GCC target triplet: *-*-mingw32 *-*-cygwin http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39518