#0  0x00007f63f04c31bd in __lll_lock_wait () from /lib64/libpthread.so.0
No symbol table info available.
#1  0x00007f63f04c0ded in pthread_cond_signal@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
No symbol table info available.
#2  0x00007f63d3cfa438 in notify_one ()
    at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libstd/sys/unix/condvar.rs:52
No locals.
#3  notify_one () at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libstd/sys_common/condvar.rs:39
No locals.
#4  notify_one () at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libstd/sync/condvar.rs:208
No locals.
#5  std::thread::{{impl}}::unpark () at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libstd/thread/mod.rs:633
No locals.
#6  0x00007f63d3c583d1 in crossbeam::sync::ms_queue::{{impl}}::push<futures_cpupool::Message> (self=<optimized out>, t=...)
    at /home/kwilson/.cache/pants/rust-toolchain/registry/src/github.com-1ecc6299db9ec823/crossbeam-0.2.10/src/sync/ms_queue.rs:178
        guard = <optimized out>
        self = <optimized out>
#7  0x00007f63d3c588ed in futures_cpupool::{{impl}}::drop (self=<optimized out>)
    at /home/kwilson/.cache/pants/rust-toolchain/git/checkouts/futures-rs-a4f11d094efefb0a/f7e6bc8/futures-cpupool/src/lib.rs:236
        self = 0x37547a0
#8  0x00007f63d3be871c in engine::fs::{{impl}}::post_fork (self=0x3754778) at /home/kwilson/dev/pants/src/rust/engine/src/fs.rs:355
        self = 0x3754778
#9  0x00007f63d3be10e4 in engine::context::{{impl}}::post_fork (self=0x37545b0)
    at /home/kwilson/dev/pants/src/rust/engine/src/context.rs:93
        self = 0x37545b0
#10 0x00007f63d3c0de5a in {{closure}} (scheduler=<optimized out>) at /home/kwilson/dev/pants/src/rust/engine/src/lib.rs:275
        scheduler = 0x3740580
#11 with_scheduler<closure,()> (scheduler_ptr=<optimized out>, f=...) at /home/kwilson/dev/pants/src/rust/engine/src/lib.rs:584
        scheduler = 0x3740580
        scheduler_ptr = 0x3740580
#12 engine::scheduler_post_fork (scheduler_ptr=0x3740580) at /home/kwilson/dev/pants/src/rust/engine/src/lib.rs:274
        scheduler_ptr = 0x3740580
#13 0x00007f63d3c1be8c in _cffi_f_scheduler_post_fork (self=<optimized out>, arg0=0x35798f0) at src/cffi/native_engine.c:2234
        _save = 0x34a65a0
        x0 = 0x3740580
        datasize = <optimized out>
#14 0x00007f63f07b5a62 in PyEval_EvalFrameEx () from /lib64/libpython2.7.so.1.0
No symbol table info available.
#15 0x00007f63f07b7e3d in PyEval_EvalCodeEx () from /lib64/libpython2.7.so.1.0

$ gr 'post_fork\(' src/python/pants/
src/python/pants//bin/daemon_pants_runner.py:          self._graph_helper.scheduler.post_fork()
src/python/pants//engine/scheduler.py:  def post_fork(self):
src/python/pants//engine/scheduler.py:    self._native.lib.scheduler_post_fork(self._scheduler)
src/python/pants//engine/scheduler.py:  def post_fork(self):
src/python/pants//engine/scheduler.py:    self._scheduler.post_fork()
src/python/pants//engine/subsystem/native.py:void scheduler_post_fork(Scheduler*);
src/python/pants//pantsd/service/scheduler_service.py:    self._scheduler.post_fork()