Altivec Linux support in GCC

[Kumar Gala]

> On Mon, Apr 14, 2003 at 12:49:48PM -0500, Kumar Gala wrote:
> > 1. What are there two options to enable the support? (-maltivec
> > -mabi=altivec).  If I have a Linux PPC targeted GCC why do I need to
> > tell it to use the abi to get altivec code generation?  This just seems
> > confusing to the user (I dont have to specify the abi for any other
> > option).
>
> This is actually very useful when mixing altivec and non-altivec code
> - for example you compile most of your program as non-altivec code,
> and you write an altivec-enabled version of the most critical
> routines, and at runtime you can detect if you have altivec and go use
> the right routine. In that context, you want to compile your altivec
> code with -maltivec but NOT -mabi=altivec.
>

I'm not sure I follow.  If you have two versions (one w/altivec & one w/o)
what effect does it have if you where to enable the -mabi=altivec option?
It would not seem to change anything else.  It should only effect the
generation of AltiVec related code.  Maybe I'm missing something here.

- kumar