https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78351
--- Comment #5 from Dr. Kevin B. Beard <kevin.b.beard at nasa dot gov> --- I've always understood that a comma will terminate a FORTRAN field - for example: https://docs.oracle.com/cd/E19957-01/805-4939/z4000743a36d/index.html Am I misunderstanding the F77 standard? Also, "-std=legacy" doesn't help. It is difficult to modify many millions of lines of legacy code to change that.