Re: 32 bit musl?

[Rich Felker <dalias@libc.org>]

On Wed, Oct 05, 2016 at 06:20:55PM -0400, John Mudd wrote:
> I've been using musl on a 32-bit Linux to build 32-bit apps to run on 32
> and 64-bit Linux machines. That works well.
> 
> I upgraded to a 64 bit development box. I've assumed I would just need to
> use -m32 option and I could still build 32 bit apps on my 64 bit machine. I
> tried it but it tries to mix 32 & 64 bit code. I guess I was naive.
> 
> It looks like I should build a cross compiler? I see several suggestions on
> how to do this so I'm not confident this will work well. Or would it be
> easier if I just installed a 32 bit Linux in a VM just for building 32 bit
> apps with musl?

GCC's multilib (-m32) is built on the assumption that the same set of
headers can be used. This is generally an invalid assumption, not just
for libc but for third-party libraries whose headers might be in the
include paths too. In principle you could hack on the gcc spec files
to get it to use different include paths for different ABIs, but a
dedicated cross compiler is an easier approach.

Rich