VMS Help FORTRAN, /PAD_SOURCE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  /[NO]PAD_SOURCE                  D=/NOPAD_SOURCE

  Controls how the compiler treats program source lines which are
  shorter than the statement field width (72 characters, or 132
  characters if /EXTEND_SOURCE is in effect.)  This option has
  an effect on how the compiler treats character, Hollerith and
  RAD50 constants which are continued across two or more source
  lines.

  Specifying /PAD_SOURCE causes the compiler to treat short source
  lines as if they were padded with blanks out to the statement
  field width.  This may be useful when compiling programs developed
  for non-Compaq platforms which may assume that short source
  lines are blank-padded.

  The default is /NOPAD_SOURCE, compatible with current and previous
  Compaq Fortran 77 compilers, which causes the compiler to not treat
  short source lines as padded with blanks so that the first character
  of a continuation line immediately follows the last character of the
  previous line.

  If /NOPAD_SOURCE is in effect, the compiler will issue an
  informational diagnostic if it detects a continued constant which
  may be affected by blank padding.  See the Release Notes for further
  details.