glibc 2.12 support

[Florian Weimer]

* erik joelsson:

> Hello Florian,
>
> We still build with glibc 2.12 in the sysroot at Oracle as we still
> support Oracle Linux 6 (which uses glibc 2.12), so I'm afraid we still 
> need it.

Fair enough.  I will tack another thing to the side of this then. 8->

Thanks,
Florian