Comment # 16 on bug 957061 from Daniel Dadap

(In reply to Oliver Neukum from comment #15)
> Hi, what is the fix? It seems to me that the root cause is in libpthread.

A lock was being destroyed twice, which is undefined behavior. This was a bug
in the NVIDIA EGL driver, which so far seems to result in adverse effects only
when lock elision is enabled in glibc.