Re: [uClinux-dev] New cross target for uClinux

[David McCullough <davidm at snapgear dot com>]

Jivin Bernardo Innocenti lays it down ...
> Hello,
> 
> I'm cleaning up uClinux patches for GCC to move all uClinux-specific target
> configuration changes away from the m68k-elf target.
> 
> Up to now, the whole uClinux toolchain was configured for the m68k-elf target,
> which is not appropriate since binaries produced by this toolchain are neither
> really ELF, nor suitable for running on bareboard targets.

I would disagree with this to some extent.  It does produce elf files,
along with flat files ;-)

We use the m68k-elf compiler to build bootloaders and all manner of
different things (including the kernel which is elf) so it hasn't seems
like a bad fit IMO.

...
> Since the 'm68k-elf' target has been in use for several years on uClinux,
> There are far too many places in the uClinux build infrastructure where m68k-elf
> is assumed and I can't patch them all at the same time. We also need to make
> the uClinux source base compatible with both the old and new GCC toolchains
> for some time.


I would agree with this.  I don't think too many people will switch to
the new toolchain immediately as the existing toolchain is working fine
for them.  There are still uClinux people who use the coff tools !


> I'd like to reduce the impact of the target change by installing GCC with a
> backwards-compatible prefix (i.e.: m68k-elf-gcc, etc.).
> 
> I'm also soft-linking /usr/local/m68k-elf to /usr/local/m68k-uclinux to let
> the compiler find gas and ld properly. I also had to softlink m68k-elf-ar to
> build libgcc.
> 
> But I've just realized this thing is requiring too many kludges. Is there
> something I can do, perhaps in config.gcc, to tell GCC it should be using a
> different target prefix for binutils and uClibc?


What is the conflict/delemma within gcc with sticking to m68k-elf ?
If the changes to gcc are mostly generic,  then we could provide and
m68k-elf toolchain and a m68k-XXXX toolchain for those that what the
uclinux targeted compiler I guess.

Alternatively,  we could say the the 2.95 based compiler is m68k-elf and
the 3.x compiler is whatever,  and until you convert your platform to
the new compiler it uses the old one.  At least this way one can have
both the old and new compilers on their system and switch relatively
easily between them (just a config.arch edit for uclinux users),

Cheers,
Davidm

-- 
David McCullough, davidm@snapgear.com  Ph:+61 7 34352815 http://www.SnapGear.com
Custom Embedded Solutions + Security   Fx:+61 7 38913630 http://www.uCdot.org