The source for this package can be obtained by extracting the ffcall and src/m4
directories from the clisp 2.41 tarball available at:
  http://prdownloads.sourceforge.net/clisp/clisp-2.41.tar.gz

The source from that tarball contains fixes for powerpc compilation, compared
to the official upstream sources available at:
  http://www.haible.de/bruno/packages-ffcall.html