EventDisplay hang in beginjob when compiled debug

[brownd1978]

A debug compiled version of EventDisplay hangs in beginJob at this line. It is apparently deadlocked waiting for the mutex to return.

[brownd1978]

At the hang there are only 2 active threads, the primary and one that appears to be corrupt:
(gdb) thread apply all bt
Thread 2 (Thread 0x7fffd8f42640 (LWP 916394) "mu2e"):
#0 clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:62
#1 0x0000000000000000 in ?? ()

[brownd1978]

Perhaps related: EventDisplay segvs when advancing to the next event EventDisplay crashes. Gdb indicates the main thread is in a wait, which may be relevant to the above, or it may just mean the crash is in a different thread.