Add Android related compilation options and multilib options

[Chris Lattner]

On Jun 16, 2009, at 3:36 PM, Joseph S. Myers wrote:

> On Tue, 16 Jun 2009, Mark Mitchell wrote:
>
>> Chris Lattner wrote:
>>
>>> That said, if it were my choice, I'd strongly prefer making  
>>> android it's
>>> own target triple.  If you want to make GCC more dynamic, make it  
>>> work
>>> with multiple target triples first.
>>
>> I disagree.  Working with multiple target triplets is a fine thing,  
>> but
>> not inventing triplets you don't need is another.  The idea that the
>
> powerpc-linux is a good case in point of having too many triplets,  
> with
> variants such as powerpc64-*-linux*, powerpc-*-linux*spe*,
> powerpc-*-linux*paired*, powerpc*-*-linux*altivec* that should just be
> variants on the default options and multilibs for one target triplet.

Why is "more targets bad"?  Life seems simple if you have one set of  
libraries for each target triple, so you have a "many target triples  
to one set of libraries" mapping.  This implies that the major ABI  
differences get different triples though.

-Chris