segfault running partitioning example about legion HOT 4 CLOSED

(lldb) thread backtrace
* thread #1: tid = 0xf81c8, 0x000000010001a000 partitioning`LegionRuntime::LowLevel::Runtime::get_reservation_impl(this=0x0000000101001200, r=Reservation at 0x00007fff5fbfdae8) + 352 at shared_lowlevel.cc:4683, queue = 'com.apple.main-thread, stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
    frame #0: 0x000000010001a000 partitioning`LegionRuntime::LowLevel::Runtime::get_reservation_impl(this=0x0000000101001200, r=Reservation at 0x00007fff5fbfdae8) + 352 at shared_lowlevel.cc:4683
    frame #1: 0x0000000100019e05 partitioning`LegionRuntime::LowLevel::Reservation::acquire(this=0x00007fff5fbfdbf0, mode=1, exclusive=false, wait_on=Event at 0x00007fff5fbfdb80) const + 85 at shared_lowlevel.cc:1114
    frame #2: 0x00000001000e2585 partitioning`LegionRuntime::HighLevel::AutoLock::AutoLock(this=0x00007fff5fbfdcb0, r=LegionRuntime::HighLevel::Reservation at 0x00007fff5fbfdbf0, mode=1, exclusive=false, wait_on=LegionRuntime::HighLevel::Event at 0x00007fff5fbfdbe0) + 117 at legion_utilities.h:196
    frame #3: 0x00000001000c9f98 partitioning`LegionRuntime::HighLevel::AutoLock::AutoLock(this=0x00007fff5fbfdcb0, r=LegionRuntime::HighLevel::Reservation at 0x00007fff5fbfdc20, mode=1, exclusive=false, wait_on=LegionRuntime::HighLevel::Event at 0x00007fff5fbfdc10) + 56 at legion_utilities.h:207
    frame #4: 0x00000001001be2f0 partitioning`LegionRuntime::HighLevel::RegionTreeForest::has_tree(this=0x000000010091e280, tid=1) const + 128 at region_tree.cc:2015
    frame #5: 0x00000001001ac167 partitioning`LegionRuntime::HighLevel::RegionTreeForest::get_node(this=0x000000010091e280, handle=0x00007fff5fbfe980) + 279 at region_tree.cc:1845
    frame #6: 0x00000001001b5dd1 partitioning`LegionRuntime::HighLevel::RegionTreeForest::close_physical_context(this=0x000000010091e280, ctx=RegionTreeContext at 0x00007fff5fbfe9d8, req=0x0000000100f29630, mappable=0x000000010286ec00, parent_ctx=0x000000010286ec00, local_proc=LegionRuntime::HighLevel::Processor at 0x00007fff5fbfe9b8, ref=0x0000000100f29710, index=0, log_name=0x0000000100480fd3, uid=29) + 209 at region_tree.cc:1158
    frame #7: 0x00000001000c2683 partitioning`LegionRuntime::HighLevel::CloseOp::trigger_execution(this=0x0000000100f29570) + 291 at legion_ops.cc:3455
    frame #8: 0x000000010034416b partitioning`LegionRuntime::HighLevel::Runtime::trigger_op_task(args=0x0000000100911230, arglen=16, p=LegionRuntime::HighLevel::Processor at 0x00007fff5fbfeb08) + 59 at runtime.cc:10495
    frame #9: 0x0000000100020bdf partitioning`LegionRuntime::LowLevel::ProcessorImpl::execute_task(this=0x000000010091bbb0, permit_shutdown=true) + 6559 at shared_lowlevel.cc:1944
    frame #10: 0x000000010001f227 partitioning`LegionRuntime::LowLevel::ProcessorImpl::run(this=0x000000010091bbb0) + 935 at shared_lowlevel.cc:1757
    frame #11: 0x0000000100021537 partitioning`LegionRuntime::LowLevel::ProcessorImpl::start(p=0x000000010091bbb0) + 327 at shared_lowlevel.cc:1991
    frame #12: 0x00000001000307de partitioning`LegionRuntime::LowLevel::Machine::run(this=0x0000000100803af0, task_id=0, style=ONE_TASK_ONLY, args=0x0000000000000000, arglen=0, background=false) + 1486 at shared_lowlevel.cc:4466
    frame #13: 0x000000010033f6f2 partitioning`LegionRuntime::HighLevel::Runtime::start(argc=1, argv=0x00007fff5fbff920, background=false) + 1474 at runtime.cc:9568
    frame #14: 0x0000000100099b8a partitioning`LegionRuntime::HighLevel::HighLevelRuntime::start(argc=1, argv=0x00007fff5fbff920, background=false) + 42 at legion.cc:2702
    frame #15: 0x0000000100003ab4 partitioning`main(argc=1, argv=0x00007fff5fbff920) + 452 at partitioning.cc:405
    frame #16: 0x00007fff939885fd libdyld.dylib`start + 1