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(g77-300.info)Source Form

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Source Form
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   GNU Fortran accepts programs written in either fixed form or free
form.

   Fixed form corresponds to ANSI FORTRAN 77 (plus popular extensions,
such as allowing tabs) and Fortran 90's fixed form.

   Free form corresponds to Fortran 90's free form (though possibly not
entirely up-to-date, and without complaining about some things that for
which Fortran 90 requires diagnostics, such as the spaces in the
constant in `R = 3 . 1').

   The way a Fortran compiler views source files depends entirely on the
implementation choices made for the compiler, since those choices are
explicitly left to the implementation by the published Fortran
standards.  GNU Fortran currently tries to be somewhat like a few
popular compilers (`f2c', Digital ("DEC") Fortran, and so on), though a
cleaner default definition along with more flexibility offered by
command-line options is likely to be offered in version 0.6.

   This section describes how `g77' interprets source lines.

Carriage Returns

Carriage returns ignored.

Tabs

Tabs converted to spaces.

Short Lines

Short lines padded with spaces (fixed-form only).

Long Lines

Long lines truncated.

Ampersands

Special Continuation Lines.