legion: Hang at start up on multinode runs

If HTR is compiled on the latest version of master, it hangs at startup when executed on multiple nodes. I think that the top-level task does not even start its execution. The backtraces obtained on a two-node execution are contained in the attached files bt_0.log bt_1.log

The backtraces are produced on sapling but the problem reproduces on every system that I have tried so far.