:Hi Mr. W. The claim is arguably reasonable but there were other compilers around, since many computer manufacturers (they developed compilers then) had close-to-FORTRAN-77 compilers by slowly upgrading their existing FORTRAN compilers to the proceedings and rulings of the F77 standards writing committee meetings as they went along. This also caused misfirings. Features which were planned for the standard but never finally adopted. But left sometimes in these compilers. There likely were other cases. Re-wording is best, making the claim softer. Bests. - (Bob)