multilib question

[Ralf Corsepius]

On Thu, 2005-11-10 at 10:10 -0800, Till Straumann wrote:
> Ralf Corsepius wrote:
> > On Thu, 2005-11-10 at 09:07 -0800, Till Straumann wrote:
> > 
> >>Ralf Corsepius wrote:
> >>
> >>>On Wed, 2005-11-09 at 22:06 -0800, Till Straumann wrote:
> >>>
> >>>
> >>>>I want to build gcc/newlib with the following variants:
> >>>>
> >>>>-mcpu=860 -soft-float
> >>>>-mcpu=603e -Dmpc8260
> >>>>-mcpu=604
> >>>>-mcpu=7400 -mabi=altivec -maltivec -mvrsave=yes
> >>>>-mcpu=7400 -mabi=altivec -maltivec -mvrsave=no
> >>>>-mcpu=7400 -mabi=altivec -mno-altivec
> >>>>
> >>>>how do I have to set the MULTILIB_xxx variables in 't-rtems' ?
> >>>
> >>OK, let me simplify my question:
> >>
> >>I want something like MULTILIB_EXTRA_OPTS but it should only
> >>apply to one specific variant. E.g., -mcpu=7400 should always
> >>activate -mabi=altivec but -mabi=altivec should not be active
> >>on other cpus.
> > 
> > Generally speaking, this means adding an extra element to the vector of
> > multilibs.
> > 
> > I.e.
> > * to extend MULTILIB_OPTIONS and MULTILIB_DIRNAMES by one element,
> > * to extend MULTILIB_EXCEPTIONS to remove all those permutations of
> > flags you don't want.
> 
> How can I tell MULTILIB_EXCEPTIONS that I dont want
> 
> mcpu=m7400 !mabi=altivec
> 
> (mcpu=m7400 *without* mabi=altivec)?

Depends on how your vector looks like:

Assuming you have
MULTILIB_OPTIONS = mcpu=7400 mabi=altivec

MULTILIB_EXCEPTIONS = mcpu=7400
probably will do.

Note: MULTILIB_EXCEPTIONS use wildcards. In this case above the
wildcards are missing, so this would only match to "-mcpu=7400" but let
"-mcpu=7400 -mabi-altivec" pass through.

BTW: AFAIS, rs6000/t-spe in gcc-4.0.x seems to be pretty close to what
you want.

Ralf