[Buildroot] continued issues with AR

[Lionel Landwerlin]

Le dimanche 26 décembre 2010 à 08:15 -0600, Heiko Zuerker a écrit :
> Quoting Lionel Landwerlin <llandwerlin at gmail.com>:
> 
> > Le samedi 25 décembre 2010 à 10:20 -0600, Heiko Zuerker a écrit :
> >> Hey,
> >>
> >> it seems like I keep running into issues where it tries to use my
> >> local ar, instead of the one from the external toolchain.
> >> I'm not familiar with the workings behind the scenes of buildroot, but
> >> is it possible that something is missing somewhere?
> >> Do we need to always set i.e. AR=$(TARGET_AR) ?
> >> Could the same be happening for other files like ld,gcc and so on?
> >>
> >
> > Yup,
> >
> > As some others packages, lvm2 does not use automake. So makefiles
> > remains mostly "hand written"...
> >
> > With fully autotooled packages, we define CC/AR/LD/etc... variables at
> > configure time, so the configure script generates the makefiles with
> > proper CC/AR/LD/etc... variables definitions.
> > With semi autotooled packages as lvm2, we rely on what as been written
> > by the lvm2 developers.
> >
> > One solution could be to define a kind of Makefile.half.autotool.in top
> > makefile to handle these specials cases (which do not seem that special
> > after all), in which we would define AR/CC/LD/etc... at build time (most
> > of them are defined in TARGET_CONFIGURE_OPTS already).
> >
> > What do you think ?
> 
> Wouldn't it make sense to always define the variables, using a subset  
> of TARGET_CONFIGURE_OPTS? Don't we always need them to point to the  
> cross compiler?

It really depends on the package's makefiles... Take zlib for example,
even if it does not use autoconf and automake, at build time, it still
uses the CC/AR/LD variables given at configure time.

I'm not sure about the right solution to this problem (the
TARGET_CONFIGURE_OPTS subset looks simpler)... Maybe someone knows why
we don't use to set CC/AR/etc... at build time ?

> 
> Or maybe some configuration variable you could specify in the  
> Makefile, which then takes care of all the magic.

Some makefile uses a CROSS prefix to set all the CC/AR/etc... variables.
I think it's a good idea, but I don't think we can afford to teach every
single developer how to write its makefiles.

After all, that's what autotools are made for, hide you all the
complicated/tedious/boring stuff like that and let you express in a
simple way what you want to build.

Regards,

--
Lionel Landwerlin