David Lichteblau)
* optimization: DYNAMIC-EXTENT declarations for lists and closures
are treated as requests for stack allocation on the x86-64,
- Alpha-32, and PPC platforms.
+ Alpha-32, PPC and SPARC platforms.
* contrib improvement: it's harder to cause SOCKET-CLOSE to close()
the wrong file descriptor; implementation of SOCKET-OPEN-P.
(thanks to Tony Martinez)