Re: ac_configure_args

[Ralf Wildenhues]

Hi Sam,

* Sam Steingold wrote on Tue, Sep 28, 2010 at 05:51:04PM CEST:
> how do I get access to all the configure arguments?
> 
> my setup is as follows:
> configure (generated from configure.in) generated shell script
> makemake from makemake.in:
> AC_CONFIG_FILES([makemake],[
>   echo "#!$SHELL" > makemake.tmp
>   echo "# Generated from makemake.in by configure using:" >> makemake.tmp
>   echo "CONFIG_SHELL=$SHELL" >> makemake.tmp
>   cat makemake >> makemake.tmp
>   mv makemake.tmp makemake
>   chmod a+x makemake
> ])

Why are you making things so complicated?

AC_SUBST([SHELL])
AC_SUBST([module_configure_flags], ["$ac_configure_args"])
AC_CONFIG_FILES([makemake], [chmod a+x makemake])

and in makemake.in:

#! @SHELL@
# Generated from makemake.in by configure using:
CONFIG_SHELL="@SHELL@"  # mind the quoting, for args like -x.
...
$srcdir/subdir/configure @module_configure_flags@


Of course, there are several small but important details to be aware of:

- $ac_configure_args is quoted in a way suitable for evaluation.  That
makes the above work.

- $ac_configure_args must be corrected for sub configures: --srcdir
needs adjustment, --cache-file too, some args may need to be pruned.
AC_INIT and AC_CONFIG_SUBDIRS currently share this task.

- $ac_configure_args is not documented; but realizing that it is used in
several third-party packages, changing it without good reason is not
likely to happen.  The documented way to get at configure args is to
save "$@" very soon after AC_INIT.

Hope that helps.

Cheers,
Ralf