Better failed assertion then silent data corruption

This is part 1 of the fix to bug 246152, and makes the bug
reproducable as failed assertion also on Ubuntu 10.10 on 64bit
machines. However, the test needs to be compiled 32bit (-m32).

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@11523 a5019735-40e9-0310-863c-91ae7b9d1cf9
1 file changed