Re: [middle-end,patch] Making __builtin_signbit type-generic

[Paolo Carlini]

.. I think this improvement means that in principle we could revert 
what we committed for libstdc++/58625, thus increasing a little the 
consistency wrt the other classification facilities in c_global/cmath 
(and c_std/cmath). Not sure it's worth it.

Jon?
Thanks,
Paolo.