gcc 4.7.1 C++ static local initialization hangs

... and resumes if a thread is kicked with a signal. No core dump or stack trace available.

Has anyone ever seen this behavior before and been able to annotate to any known gcc/glibc bugs?

Seen it once on a RHEL 5.5 Westmere and once on a RHEL 6.5 Sandybridge. First time I did do pstack and it was inside the cxa_guard_acquire local static initialization generated guard, running pstack (=attaching/detaching gdb) resumed the thread that time.