Fix BZ #342683. Based on patch by Ivo Raisr.
What this does is to make sure that the initial client data segment
is marked as unaddressable. This is consistent with the behaviour of
brk when the data segment is shrunk. The "freed" memory is marked
as unaddressable.
Special tweaks were needed for s390 which was returning early from
the funtion to avoid sloppy register definedness initialisation.

git-svn-id: svn:// a5019735-40e9-0310-863c-91ae7b9d1cf9
3 files changed