bootstrap broken: nan() does not match prototype

[Kaveh R. Ghazi]

 > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13814
 > Gruss
 > Andreas

I just posted a followup in the PR, we can probably remove nan.c from
libstdc++.

		--Kaveh
--
Kaveh R. Ghazi			ghazi@caip.rutgers.edu