pthread_mutex_lock sometimes fails on Linux 2.4.5

On a 4P Lion with Red Hat 7.0.98 installed and a 2.4.5 kernel, a 4P fft application sometimes hangs in a barrier. All 4 threads get into the barrier and none get out because a count gets up to 3 and they are waiting for it to get to 4. I changed my barrier code to use an assembly language lock instead of pthread_mutex_lock(), and it works reliably now. Either there is a bug in pthread_mutex_lock, or else a memory management bug in the kernel. I've worked around this and it is not causing me a problem now. If anyone wants to investigate and debug this, I'll be glad to supply a test case.

David Robboy