f2c
Currently, g77 does not include f2c itself in its
distribution.
However, it does include a modified version of the libf2c.
This version is normally compatible with f2c, but has been
modified to meet the needs of g77 in ways that might possibly
be incompatible with some versions or configurations of f2c.
Decide how installation of g77 should affect any existing installation
of f2c on your system.
If you do not have f2c on your system (e.g. no `/usr/bin/f2c',
no `/usr/include/f2c.h', and no `/usr/lib/libf2c.a',
`/usr/lib/libF77.a', or `/usr/lib/libI77.a'), you don't need to
be concerned with this item.
If you do have f2c on your system, you need to decide how users
of f2c will be affected by your installing g77.
Since g77 is
currently designed to be object-code-compatible with f2c (with
very few, clear exceptions), users of f2c might want to combine
f2c-compiled object files with g77-compiled object files in a
single executable.
To do this, users of f2c should use the same copies of `f2c.h' and
`libf2c.a' that g77 uses (and that get built as part of
g77).
If you do nothing here, the g77 installation process will not
overwrite the `include/f2c.h' and `lib/libf2c.a' files with its
own versions, and in fact will not even install `libf2c.a' for use
with the newly installed versions of gcc and g77 if it sees
that `lib/libf2c.a' exists--instead, it will print an explanatory
message and skip this part of the installation.
To install g77's versions of `f2c.h' and `libf2c.a'
in the appropriate
places, create the file `f2c-install-ok' (e.g. via the UNIX
command `touch f2c-install-ok') in the source or build top-level
directory (the same directory in which the g77 `f' directory
resides, not the `f' directory itself), or edit `gcc/f/Make-lang.in'
and change the definition of the `F2C_INSTALL_FLAG' macro appropriately.
Usually, this means that, after typing `cd gcc', you would type `touch f2c-install-ok'.
Make sure that when you enable the overwriting of `f2c.h'
and `libf2c.a'
as used by f2c, you have a recent and properly configured version of
`bin/f2c' so that it generates code that is compatible with g77.
If you don't want installation of g77 to overwrite f2c's existing
installation, but you do want g77 installation to proceed with
installation of its own versions of `f2c.h' and `libf2c.a' in places
where g77 will pick them up (even when linking f2c-compiled
object files--which might lead to incompatibilities), create
the file `f2c-exists-ok' (e.g. via the UNIX command
`touch f2c-exists-ok') in the source or build top-level directory,
or edit `gcc/f/Make-lang.in' and change the definition of the
`F2CLIBOK' macro appropriately.
Go to the first, previous, next, last section, table of contents.