gcc cross-compiler for linux

[Lowell Gilbert]

Xavier Otazu <xotazu at cvc.uab.es> writes:

> Thanks a lot for this link. Now I see that I need to use the
> cross-gcc compiler.

I've never done it; I just looked it up.  

I'm sure there's more information in the archives of the mailing lists,
and you can always try to consult the port maintainer.

> I am using Matlab inside the linux emulator, and I nedd to create some
> "mex" files from matlab. In order to create these mes files, matlab
> needs access to a gcc compiler that produces linux elf files. I think I
> cannot use the gentoo-stage3 port, because in order to use I would need
> to chroot and it is not so easy from matlab. Also, when using this
> compiler I should be able to acces to the "linux"-matlab header files,
> but if I "chroot" to the gentoo port I won't be able to access them.

They should be inside the compat/linux tree, and therefore accessible.

> I tried to install the devel/cross-gcc port, but I get errors when
> compiling it.

Um, fix the errors?

> I have some doubts about the wiki link you sent me:
>
> 1) What really means "null-mount the home directory"? I google-d some
> info, but I didn't find good information. What really exactly means
> "corresponding entries in the passwd and shadow files are required
> then"?

a) "man mount_nullfs"

b) I would guess that /compat/linux/etc/{passwd,shadow} need to have
   entries to match your /etc/master.passwd.  I can't check for sure 

> 2) What really means "All you have to do is to compile the ports and
> add includes and libs from the linux system your target in your
> development"? Do I have to include the linux headers during
> devel/cross-gcc port building? Or do I have to include them when
> cross-compiling my code?

Logically, I would think that would apply to compiling *your* code.
Anything that's need to build the port should be handled by the port
itself.  

> What options do I have to use when building the linux gcc
> cross-compiler? I use 

I don't know; all I can tell you is that you seem to be on the right
path here.

> make TGTARCH=i386 TGTABI=linux install clean
>
> Thanks a lot for your help
>
> Cheers
>
> Xavier
>
> On Tue, 25 Nov 2008 15:04:27 -0500
> Lowell Gilbert <freebsd-questions-local at be-well.ilk.org> wrote:
>
>> Xavier Otazu <xotazu at cvc.uab.es> writes:
>> 
>> > I would like to compile a C++ code to be executed within the linux
>> > emulator.
>> 
>> http://wiki.freebsd.org/linux-xdev

Good luck.
-- 
Lowell Gilbert, embedded/networking software engineer, Boston area
		http://be-well.ilk.org/~lowell/