Re: Host settings for GNU in configure*?

[Guillem Jover]

Hi!

On Thu, 2011-08-25 at 10:58:43 +0200, Svante Signell wrote:
> On Thu, 2011-08-25 at 10:48 +0200, Samuel Thibault wrote:
> > Svante Signell, le Thu 25 Aug 2011 10:20:44 +0200, a écrit :
> 
> > > 1) Where to find the specification resulting in i486-pc-gnu?
> > 
> > I don't understand the question. Why would you want that ?
> 
> Some packages are configured with i486-pc-gnu, you find it in
> config.log. Where does this come from in configure* If not specified
> config.guess gives i686-unknown-gnu0.3.

It comes from configure running “config.sub i486-gnu”. The i486-gnu
comes from dpkg-architecture's DEB_HOST_GNU_TYPE variable passed to
configure as --host.

> > > A common denominator of $host is
> > > 
> > > c) *-gnu*
> > 
> > This one: don't care the actual architecture, don't care the actual
> > version of GNU.
> 
> It is not unique if * means wildcard, Is that not needed?

It depends on what's supposed to be matched, if it's any GNU system
then the wildcard is what you want, if you only want some of the
variants then it needs to be more restrictive.

> > > 6) Are these only local to the rules file?
> > 
> > I don't understand the question. They are dpkg-architecture output,
> > that's all.
> 
> Yes, and they are used for logic in the rules (Makefile) right?, and not
> exported in any way to configure*/outside ?

DEB_HOST_ARCH* (and DEB_BUILD_ARCH* but that's generally wrong) are the
variables that should generally be used in debian/rules files.
DEB_BUILD_GNU_* and DEB_HOST_GNU_* are the ones that should be used
when dealing with the GNU build system, usually only passed to configure
through the --build and --host options.

regards,
guillem