[Android] Enable ifuncs on Android

[Jeff Law]

On 11/13/14 21:46, H.J. Lu wrote:

>
> Hi Jeff,
>
> I believe the patch is correct.  Not all glibcs support IFUNC. It doesn't mean
> we should disable IFUNC for all glibcs.  By default, we do a configure time
> check for IFUNC.  We DO want to use configure time check for IFUNC for
> Android NDK.
>I
I'm sorry, I'm objecting to this patch.  It is wrong for GCC to produce 
code that is incorrect solely for the benefit of optimizing for a new 
release of a library.

The right way is to trigger the new code on some configure time option 
or a new configuration itself.

Whether or not GCC is doing this right for glibc is irrelevant, the 
patch is _wrong_.

jeff