[libvirt] [jenkins-ci PATCH v5 5/5] lcitool: support generating cross compiler dockerfiles

[Andrea Bolognani]

On Thu, 2019-02-28 at 18:03 +0000, Daniel P. Berrangé wrote:
> On Thu, Feb 28, 2019 at 06:46:41PM +0100, Andrea Bolognani wrote:
> > Okay, so I guess you need to have cross_target=i686-linux-gnu for
> > 
> >   ENV CONFIGURE_OPTS "--host={cross_target} \
> >                       --target={cross_target}"
> > 
> > to work; however, that will cause issues for
> > 
> >   ENV PKG_CONFIG_LIBDIR "/usr/lib/{cross_target}/pkgconfig"
> > 
> > because as shown above paths look like
> > 
> >   /usr/lib/i386-linux-gnu/pkgconfig/glib-2.0.pc
> > 
> > and so on. What an inconsistent mess! Does it mean we need to
> > carry around both? :(
> > 
> > 
> > ... Actually, it doesn't look like it: I just tried cross-building
> > for i686 (on sid/x86_64) by simply passing
> > 
> >   --host=i686-linux-gnu --target=i686-linux-gnu
> > 
> > and the build system was able to locate all necessary dependencies
> > despite not having set $PKG_CONFIG_LIBDIR in the environment!
> > 
> > This seems to be thanks to i686-linux-gnu-pkg-config, which is a
> > symlink to /usr/share/pkg-config-crosswrapper, being picked up and
> > invoked instead of the native one.
> 
> Interesting. I'll have to check this again. In my previous versions
> of this series, pkgconfig was mistakenly finding the native .pc
> files, and PKG_CONFIG_LIBDIR was needed to fix it. So that can't have
> been using the i686-linux-gnu-pkg-config binary before. I'll try and
> see what changed..

Unfortunately that only seems to apply to Debian Sid: the version
of pkg-config in Debian 9 is quite a bit older and apparently not
as smart.

So we need to have $PKG_CONFIG_LIBDIR in the environment after all,
and also deal with the mess described above somehow :(

-- 
Andrea Bolognani / Red Hat / Virtualization