Re: [Qemu-devel] [Xen-devel] [PATCH v2] qemu/configure: fix CFLAGS handling for i386

[Peter Maydell]

On 4 April 2012 16:16, Ian Jackson <address@hidden> wrote:
> Olaf Hering writes ("[Xen-devel] [PATCH v2] qemu/configure: fix CFLAGS 
> handling for i386"):
>> configure will generate incorrect CFLAGS which will lead to compile
>> errors due to unknown gcc options, iff CFLAGS was already in the
>> environment during configure invocation.
>
> Don't do that then.
>
> In general, CFLAGS is not a variable you can safely set in your
> environment when invoking a nonconsenting build system.

Yes. You probably wanted configure's --extra-cflags option.
However that doesn't mean the code in configure at the moment
is actually right...

Having looked at configure I'm pretty sure what we want here is
  QEMU_CFLAGS="-march=i486 $QEMU_CFLAGS"

because we're only doing this for the benefit of a particular bit
of code in hw/vhost.c and so QEMU_CFLAGS is sufficient. Also this
brings it into line with other places where we add a -march flag,
which use QEMU_CFLAGS, not CFLAGS.

-- PMM