Re: multilib thumb code for arm-linux-gnueabi-gcc

[Loïc Minier <lool@dooz.org>]

On Mon, Nov 05, 2012, chrysn wrote:
> i rather thought of them as different levels of tuning, where the
> different multi-arch architectures are "everything where you need a
> different gcc" and the different multi-lib directories are "what can be
> done with the same gcc".

At the moment, we have different multiarch triplets for different ABIs;
multi-lib is an upstream concept that allows supporting different ABIs
but also different optimization levels.

> that illusion is fading as i see that while arm-none-eabi-gcc and
> arm-linux-gnueabi-gcc are often used differently, they can produce the
> same code.

That's yet another concept: arm-none-eabi-gcc is a "bare-metal" compiler
that doesn't target any OS.  You can build bare-metal binaries (such as
U-Boot) with both compilers, but you can only build Linux binaries with
arm-linux-gnueabi-gcc.

> still, i see the case at hand more as multi-lib thing than a multi-arch
> thing for pragmatic reasons: we can't expect to have a debian
> architecture dedicated to something that won't even run linux, can we?

We have Debian architectures for kfreebsd and hurd, so why not?  :-)

Also, I believe Cortex-M can run linux with no-MMU patches/configs and
uclibc?

But it's definitely not a trivial port, you're right.

-- 
Loïc Minier