Fedora and Cross Compiling

[Oliver Falk]

On 06/08/2007 09:32 PM, Brendan Conoboy wrote:
> Oliver Falk wrote:
>> Good self introduction. Now we know, that you know what you're talking
>> 'bout. :-)
> 
> I pretend well, anyway :-)  I'll see if some more folks from my group
> will jump in here.
> 
>> True. But is cross compilation really as reliable as native compilation
>> is? I'm not experienced with cross compilation... But I think some
>> errors will only occur on *real native hardware*...
> 
> Reliable?  Sure.  But there are problems unique to cross compiling which
> must be addressed.  You don't want to pull in a host-header instead of a
> target-header.

Issue number 1.

> You also can't run the resulting executables so
> post-build testsuites can't be run.

Issue number 2.

> That said, object and executable
> generation is pretty much the same whether your cross compile or
> natively compile, so you're going to get functionally identical bits.

OK. That might be true for gcc, but how about gcj? Or other compilers?
I'm also thinking about python that emits byte-code. Is this code
machine independent? I'm not sure; Could google or read, but just want
to mention....

>> I think that's the same as with secondary arches. Yes, there must be
>> some team supporting the arch, if it's done via cross compilers or on
>> native hardware; But with one difference: The people who are involved in
>> the 2ndary arch stuff, might not be very experienced with cross
>> compilation; Like me and Alpha for example.
> 
> Right- I hope I'm not alienating the folks who want to bring Arm to the
> Fedora fold even if it means native compilation.  New arches and cross
> compiling aren't directly related, but when you put them together
> successfully it's very beneficial, but not necessary.  Still, I bet
> there are more people per capita in the secondary-arch camp interested
> in cross compiling than the primary arches.

Yes, cross compilation is an interesting; At least for me and I would be
happy to be a bit involved; You never stop learning...

>> I think for Alpha we will have enough fast machines that can get the job
>> done. I don't know about the other arches....
> 
> That's handy- how will you bootstrap?

alphacore.info. We have AC3 (FC5 based). I also was able to update large
parts to FC6 and fcdevel. glibc and gcc, well and also a newer 2.6.21
kernel:
[root at tyskie ~]# uname -a
Linux tyskie.linux-kernel.at 2.6.21-1.3125.fc7 #1 Tue May 15 14:52:47
CEST 2007 alpha alpha alpha GNU/Linux

Not all pieces of my/our specs are perfect to be commited to fedora
cvs... But I'm bugzilla-ing as much as I can and most pkg-maintainers
are helpful and willing to include alpha support; Thinking of secondary
arch support...

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