Re: _AC_CHECK_HEADER_OLD

[Eric Blake]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

According to Eric Blake on 6/15/2009 8:00 PM:
> Or is this usage of _AC_CHECK_HEADER_OLD so pervasive in the wild that we
> should make the AU_DEFUN forward to _AC_CHECK_HEADER_PREPROC instead of
> the public AC_CHECK_HEADER, the way I originally proposed?

Or even modify AU_DEFUN to take an optional fourth argument:

# AU_DEFUN(NAME, USER-REPLACEMENT, [MESSAGE],
#          [INTERNAL-REPLACEMENT = USER-REPLACEMENT])
# ---------------------------------------------------
# Define the macro NAME so that it expands to USER-REPLACEMENT
# when run by autoupdate, and to INTERNAL-REPLACEMENT when
# run by autoconf.

Thus, for this case, we could use this to break the infloop:

AU_DEFUN([_AC_CHECK_HEADER_OLD],
[AC_CHECK_HEADER([$1], [$2], [$3], [-])], [], [_AC_CHECK_HEADER_PREPROC($@)])

because autoconf would not be picking up the gcc replacement for
AC_CHECK_HEADER, but the user that runs autoupdate will still pick up on
the now-documented usage of the public API.

- --
Don't work too hard, make some time for fun as well!

Eric Blake             address@hidden
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (Cygwin)
Comment: Public key at home.comcast.net/~ericblake/eblake.gpg
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEARECAAYFAko3Al0ACgkQ84KuGfSFAYA5kwCgzkv1w5nlnFFi7vYSoAomV4hg
BoUAoJyO8yDK6dSVS4DaAyMhgGeRb2Wa
=+ArF
-----END PGP SIGNATURE-----