Re: aicasm build error

On Sat, 2013-09-14 at 20:42 +0200, Dimitry Andric wrote:
> On Sep 14, 2013, at 19:50, Ian Lepore <ian_at_freebsd.org> wrote:
> > For a while I've been getting a build error on aicasm during the early
> > steps of the build.  Today I finally dug into it and discovered it's
> > because the build is using a mix of header files, some from /usr/include
> > on the build host, and some from obj/... for the target being built.  It
> > happens because dev/aic7xxx/aicasm/Makefile contains CFLAGS+= -I. and
> > the current directory when aicasm builds is obj/.../<kernconf>.  In my
> > case it was picking up machine/_types.h from objdir.
> > 
> > Apparently this is usually harmless, but if the build host system and
> > the target versions are far enough apart, or with a cross-build where
> > the host and target are different architectures, you can get problems.  
> > 
> > After a little digging, I just now discovered Marcel fixed this long ago
> > in r70000, but then it got undone in r236578 a couple months ago.  Is
> > there any reason not to restore Marcel's fix, such as with the attached
> > patch?
> 
> It got undone for a specific reason, which is mentioned in the commit
> message for r236578.
> 
> This hack might make it work, but it might also cause other issues.  The
> problem really is how to make sure aicasm is compiled with the *host*
> compiler, not the compiler from /usr/obj.
> 
> -Dimitry
> 

What do you think about this patch, which should achieve that goal?
This builds aicasm along with the compiler and binutils and all the
other compile-related tools.  Using this, I'm able to add "device ahc"
to the kernel config of an arm cross-build and it works.  (That's not
useful of course, except to demonstrate that it now uses the right
compiler and then runs the tool successfully during a kernel build.)

I see no straighforward way to do this as part of the kernel build,
which means aicasm gets built whether your kernel config includes an
ahc/ahd device or not.  I suspect that's going to make some people
unhappy, but it takes less than a second to build aicasm on my machine,
it's really not a big burden.

-- Ian