Re: [patch] ppc SUBTARGET_OVERRIDE_OPTIONS

[Aldy Hernandez <aldyh at redhat dot com>]

> Not OK.  The whole point of those macros is that they go after, so
> that a "subtarget" can "override options".

so then if a target sets rs6000_altivec_abi, like darwin does,
then there's absolutely no way to disable it with user options?  the
compiler will completely (and silently) ignore the user options.  this
doesn't sound very good.

right now the options i moved are:

	-mdebug-
	-mabi=
	-mvrsave=

i personally don't care about -mdebug-, but i would like to be able to
disable altivec abi, or vrsave generation regardless of what the
target specified.

at the least, we should give a warning about this, not silently drop
user options.  hmm, well -mcpu= does the same things in changing
target_flags.  this is all broken.

> If you want to set a default, create a macro like TARGET_DEFAULT.

yeah, but we can't do that with either -mabi or -mvrsave because we've
run out of bits.  TARGET_DEFAULT is a mask of target_flags.  both
-mabi and -mvrsave have a separate variable.

[perhaps i should get around to doing the massive target stuff rewrite
we have talked about to free target bits]

> If you've already committed it, please back it out.

i can do if you still think this is best, but please address my questions.

cheers
aldy