https://issues.dlang.org/show_bug.cgi?id=10364
Vladimir Panteleev <dlang-bugzi...@thecybershadow.net> changed: What |Removed |Added ---------------------------------------------------------------------------- Component|dmd |druntime --- Comment #7 from Vladimir Panteleev <dlang-bugzi...@thecybershadow.net> --- I reproduced it with macOS 10.12 and DMD 2.074. Changing daemon(0,0) to daemon(0,1) (so that stderr isn't redirected to /dev/null) reveals a clue: core.thread.ThreadError@src/core/thread.d(3002): Unable to load thread state It looks like the daemon() call is interfering with Druntime's threading code. --