The .XOR. operator is supported by several vendor compilers including IBM's XL fortran, DEC fortran, SUN fortran and even GNU f77!
A patch has been proposed at: See: "[PATCH] Support .XOR. as a -std=legacy extension" http://gcc.gnu.org/ml/fortran/2007-09/msg00070.html The only problem is that this patch rejects (with -std=gnu/legacy) a user-implemented .XOR., which is valid Fortran 90/95/2003. Other compilers such as ifort and sunf95 implemented .XOR. such that by default both the intrinsic .XOR. as also a user-implemented .XOR. work; see also http://gcc.gnu.org/ml/fortran/2007-09/msg00082.html -- Summary: g77 extension: Support for the .XOR. operator Product: gcc Version: 4.3.0 Status: UNCONFIRMED Keywords: patch Severity: normal Priority: P3 Component: fortran AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: burnus at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33432
