/sys$common/syshlp/helplib.hlb FORTRAN, /STANDARD, MIA  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  Controls whether the compiler produces informational messages for
  extensions to the MIA standard, which is a superset of FORTRAN-77.
  (For more information on MIA extensions, see your user manual.)

  Specifying MIA checking enables SYNTAX checking to be performed.