XOR — Bitwise logical exclusive OR ¶Bitwise logical exclusive or.
This intrinsic routine is provided for backwards compatibility with 
GNU Fortran 77.  For integer arguments, programmers should consider
the use of the IEOR — Bitwise logical exclusive or intrinsic and for logical arguments the
.NEQV. operator, which are both defined by the Fortran standard.
GNU extension
Function
RESULT = XOR(I, J)
| I | The type shall be either a scalar INTEGERtype or a scalarLOGICALtype or a boz-literal-constant. | 
| J | The type shall be the same as the type of I or
a boz-literal-constant. I and J shall not both be
boz-literal-constants.  If either I and J is a
boz-literal-constant, then the other argument must be a scalar INTEGER. | 
The return type is either a scalar INTEGER or a scalar
LOGICAL.  If the kind type parameters differ, then the
smaller kind type is implicitly converted to larger kind, and the 
return has the larger kind.  A boz-literal-constant is 
converted to an INTEGER with the kind type parameter of
the other argument as-if a call to INT — Convert to integer type occurred.
PROGRAM test_xor LOGICAL :: T = .TRUE., F = .FALSE. INTEGER :: a, b DATA a / Z'F' /, b / Z'3' / WRITE (*,*) XOR(T, T), XOR(T, F), XOR(F, T), XOR(F, F) WRITE (*,*) XOR(a, b) END PROGRAM
Fortran 95 elemental function: 
IEOR — Bitwise logical exclusive or