Re: Platform-specific AC_ARG_*

[Ralf Wildenhues]

Hello John,

* John Calcote wrote on Mon, Jun 23, 2008 at 07:21:32PM CEST:
> 
> For example, on Solaris SPARC hosts, you can target sparc-generic code,
> if you wish, but it makes no sense to even see an option,
> - --enable-sparc-generic on an Intel Linux box.
> 
> Is there a way to use AC_ENABLE_ARG conditionally, based on the contents
> of the $host variable, for example?

Not really.  The code expansion takes place at m4 time, $host is known
only at configure time.

> I've also thought about the possibility of adding some "solaris only"
> text to the help text for the option.

Not really possible either.  How would you know that with
  ./configure --help

I am not trying to find out how to pass additional options to
  ./configure --host=sparc-sun-solaris2.10

or similar?  Of course nothing prevents you from adding '(sparc
specific)' or similar to your help text.

> I've also considered adding an AC_MSG_ERROR message if someone
> attempts to use the option on a non-Solaris/Sparc host.

Sounds like a way to go to me.  Of course, in order to allow for your
package to be cross-compiled, you really should look at $host (after
AC_CANONICAL_HOST) and not $build.

Cheers,
Ralf