libecb - e compiler builtins

This project delivers you many gcc builtins, attributes and a number of
generally useful low-level functions, such as popcount, expect, prefetch,
noinline, assume, unreachable and so on.

The home of the library is:

   http://software.schmorp.de/pkg/libecb

Please refer to ecb.pod for more information, the latest version can be
found here:

   http://pod.tst.eu/http://cvs.schmorp.de/libecb/ecb.pod