Re: using cross tools for other programs

[David Young <dyoung%pobox.com@localhost>]

On Mon, May 10, 2010 at 12:53:29PM -0400, Greg Troxel wrote:
> 
> I'm very used to building netbsd with build.sh.  I would also like to
> use the cross tools built by netbsd to build other programs for a target
> netbsd system.
> 
> Normally ld knows to link in libc and crt0, etc.  The cross tools don't
> seem to:
> 
> $ /usr/obj/gdt-5/tools/i386--netbsdelf/bin/gcc test.c
> /usr/obj/gdt-5/tools/lib/gcc/i386--netbsdelf/4.1.3/../../../../i386--netbsdelf/bin/ld:
>  crt0.o: No such file: No such file or directory
> collect2: ld returned 1 exit status
> 
> So, it seems that I have to pass flags to the linker to find a bunch of
> things, and perhaps to tell cc and ld not to look in the host system.
> In mk/bsd.prog.mk, it appears that all of those arguments are
> constructed into the link target.  I'm sure I can replicate all of that,
> but it would seem easier to have wrapper scripts that act like the
> native commands, but grab from the destdir.  In my case I am
> crossbuilding to the netbsd target I just built netbsd for, so having
> the destdir baked in is fine.
> 
> Has anyone else struggled with this?  Am I on the right track, or confused?

You can use build.sh to create a make wrapper.  To build the wrapper,
use similar build.sh options environment as you use to build NetBSD.  To
create a wrapper called 'gdtmake':

build.sh -O /usr/obj/gdt-5 -D ... -V GDTVAR1=xyz -V GDTVAR2=abc \
    -w gdtmake makewrapper

Use the wrapper to cross-build your programs:

        cd gdtsources
        ../gdtmake obj cleandir dependall

Masao Uebayasi has added a couple of options to build.sh, -Y and -y,
that may do all of the above in one step.  I haven't tried it out, yet.

Dave

-- 
David Young             OJC Technologies
dyoung%ojctech.com@localhost      Urbana, IL * (217) 278-3933