Re: [PATCH] MIPS gas: Allow simultan use of -mpu amd -mipsX again

[Thiemo Seufer <ica2_ts at csv dot ica dot uni-stuttgart dot de>]

cgd@sibyte.com wrote:
> ica2_ts@csv.ica.uni-stuttgart.de ("Thiemo Seufer") writes:
> > It also adds warnings if one of -march/-mtune/-mcpu is specified
> > more than once, what can happen under the hood even for e.g.
> > "-m4650 -march=r4000".
> 
> Is this really worthy of generating a warning?  In general, isn't the
> last option given supposed to 'win'?

IMHO at least one of both should happen, preferably the latter one.
Unfortuantly, "-m4650 -march=r4000" ends up being the same as
"-march=r4000 -mtune=4650", so the last option hasn't really won.

As far as I understand, the -m<cpu> options are only useful when
they set both -march and -mtune to their value. Since I haven't found
a easy way to fix this, I introduced the warnings.

> I'd think that it might ... cause lots of unnecessary warnings if
> e.g. there were a way to set the built-in default configuration (i've
> not looked how that's done in the new code), or if somebody did e.g.:
> 
> 	AS="mips-elf-as -march=r4000"
> 
> then later explicitly coded things in their makefiles as:
> 
> 	$(AS) -march=...

The one should fix his code. :-)

We have now -march, -mtune, -mcpu, -m<cpu>. It's a mess, and warn
about seemingly unintended use might help to standardize on the
first two.


Thiemo