Hi all,

Following discussion in 
https://gcc.gnu.org/ml/gcc-patches/2014-08/msg00016.html this patch adds 
support for fnspecs to internal function machinery which should 
(hopefully) allow compiler to perform better analysis and optimization 
of this construct.

For now the only internal functions using this machinery would be 
UBSAN_NULL and ASAN_CHECK (both would take EAF_DIRECT and EAF_NOESCAPE 
for their pointer argument).

The patch was bootstrapped and regtested on x64.

Ok for trunk?

-Y