hpux 10.20 and mmap everywhere

[John David Anglin]

Although hpux 10.20 doesn't have /dev/zero and mmap doesn't support MAP_ANON,
it recently came to my attention that mmap does support MAP_ANONYMOUS with a 
file descriptor of -1.  Also, you have to be somewhat careful the placement
of the mapped region.

The GNU gc routines will use mmap in preference to valloc if HAVE_MMAP_ANYWHERE
support is available.  Would the performance improvement from using mmap in
the gc routines be worth modifying configure and the gc routines for this
case?

Dave
-- 
J. David Anglin                                  dave.anglin@nrc.ca
National Research Council of Canada              (613) 990-0752 (FAX: 952-6605)