This change does not fix the actual bug. That was done by commit
c9db0ac6, "sort: preallocate merge tree nodes to heap". The fix
was to store each "node" structure on the heap, not on the stack.
Otherwise, a node from one thread's stack could be used in another
thread after the first thread had expired (via pthread_join).
This bug was very hard to trigger when using spinlocks, but
easier once we began using mutexes.
* NEWS (Bug fixes): Mention it.
For details, see http://debbugs.gnu.org/7597.
do no work. I.e., "sort < big-file | less" could waste a lot of power.
[bug introduced in coreutils-8.6]
+ sort with at least two threads no longer segfaults due to use of pointers
+ into the stack of an expired thread. [bug introduced in coreutils-8.6]
+
** New features
split accepts the --number option to generate a specific number of files.