musl-gcc -m32 is broken

musl-gcc -m32 is broken

[Andy Lutomirski]

Adding %{m16|m32:-m elf_i386} to the *link spec in musl-gcc.specs
fixes at least the obvious failure for me.

--Andy

Re: musl-gcc -m32 is broken

[Rich Felker]

On Wed, Aug 26, 2015 at 03:16:22PM -0700, Andy Lutomirski wrote:
> Adding %{m16|m32:-m elf_i386} to the *link spec in musl-gcc.specs
> fixes at least the obvious failure for me.

Can you clarify? musl-gcc's target is coupled to the target arch that
the corresponding musl libc was built for. Switching targets with -m32
and similar options is not going to get you correspondingly switched
libraries. Or am I misunderstanding what you're trying to do?

Rich

Re: musl-gcc -m32 is broken

[Andy Lutomirski]

On 08/26/2015 06:44 PM, Rich Felker wrote:
> On Wed, Aug 26, 2015 at 03:16:22PM -0700, Andy Lutomirski wrote:
>> Adding %{m16|m32:-m elf_i386} to the *link spec in musl-gcc.specs
>> fixes at least the obvious failure for me.
>
> Can you clarify? musl-gcc's target is coupled to the target arch that
> the corresponding musl libc was built for. Switching targets with -m32
> and similar options is not going to get you correspondingly switched
> libraries. Or am I misunderstanding what you're trying to do?

I build for an i386 target on an x86_64 Fedora system using CFLAGS=-m32. 
  It built successfully and even seems to work, but musl-gcc ends up 
omitting -m32 in the link stage, so it tries to pick up the wrong 
libraries and fails to link.

ISTM either musl-gcc should accept and honor -m32 (and work!) or 
musl-gcc should hardcode the target architecture (i.e. musl-gcc should 
target i386 even without -m32).

--Andy

Re: Re: musl-gcc -m32 is broken

[Rich Felker]

On Thu, Aug 27, 2015 at 12:58:21PM -0700, Andy Lutomirski wrote:
> On 08/26/2015 06:44 PM, Rich Felker wrote:
> >On Wed, Aug 26, 2015 at 03:16:22PM -0700, Andy Lutomirski wrote:
> >>Adding %{m16|m32:-m elf_i386} to the *link spec in musl-gcc.specs
> >>fixes at least the obvious failure for me.
> >
> >Can you clarify? musl-gcc's target is coupled to the target arch that
> >the corresponding musl libc was built for. Switching targets with -m32
> >and similar options is not going to get you correspondingly switched
> >libraries. Or am I misunderstanding what you're trying to do?
> 
> I build for an i386 target on an x86_64 Fedora system using
> CFLAGS=-m32.  It built successfully and even seems to work, but
> musl-gcc ends up omitting -m32 in the link stage, so it tries to
> pick up the wrong libraries and fails to link.

I think -m32 should be part of $CC, not $CFLAGS. Then it should get
incorporated into the musl-gcc script.

Rich

Re: musl-gcc -m32 is broken

[Andy Lutomirski]

On 08/27/2015 01:09 PM, Rich Felker wrote:
> On Thu, Aug 27, 2015 at 12:58:21PM -0700, Andy Lutomirski wrote:
>> On 08/26/2015 06:44 PM, Rich Felker wrote:
>>> On Wed, Aug 26, 2015 at 03:16:22PM -0700, Andy Lutomirski wrote:
>>>> Adding %{m16|m32:-m elf_i386} to the *link spec in musl-gcc.specs
>>>> fixes at least the obvious failure for me.
>>>
>>> Can you clarify? musl-gcc's target is coupled to the target arch that
>>> the corresponding musl libc was built for. Switching targets with -m32
>>> and similar options is not going to get you correspondingly switched
>>> libraries. Or am I misunderstanding what you're trying to do?
>>
>> I build for an i386 target on an x86_64 Fedora system using
>> CFLAGS=-m32.  It built successfully and even seems to work, but
>> musl-gcc ends up omitting -m32 in the link stage, so it tries to
>> pick up the wrong libraries and fails to link.
>
> I think -m32 should be part of $CC, not $CFLAGS. Then it should get
> incorporated into the musl-gcc script.
>

I don't suppose the configure script could be taught to do this 
automatically if I type --target=i386?  (Or at least to document this 
somehow.)

I searched for how to handle -m32 musl builds, and I got very 
conflicting advice.

--Andy