Why is 'Simulate Background Fetch' leading to crash (libsystem_kernel.dylib`mach_msg_trap) since Xcode 8?

Question

I\'m on macOS Sierra, Xcode 8, and get crashes whenever I try to Simulate Background Fetch on an actual iOS 10 device. This does NOT occur when using the simulator. This o

Answer 1

It's not crashing, something is throwing a signal to pause execution of the app. Without knowing how the simulated fetch happens I can only guess why - it might be part of the simulation or a side effect of the way the app handles it. Xcode used to support permanently disabling breaks on signals (SIGPIPE was always my bane), but that hasn't worked for several versions now.