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

  /[NO]EXTEND_SOURCE              D=/NOEXTEND_SOURCE

  Indicates whether the compiler will treat columns 7 through 72 or 7
  through 132 as the statement field in Fortran source code lines.

  This qualifier can also be specified on the OPTIONS statement.  The
  default is /NOEXTEND_SOURCE (which treats source columns 7 through
  72 as the statement field).

  If the source line extends beyond the end of the statement field,
  the extra characters are ignored.  /WARNINGS=TRUNCATED_SOURCE can
  be used to cause the compiler to issue a warning if source lines
  longer than the statement field length are encountered.