Why does "Simulate Background Fetch" crash (libsystem_kernel.dylib`mach_msg_trap) with Xcode 8?

Question

I am on macOS Sierra, Xcode 8 and get crashes whenever I try to simulate the background selection on a real iOS 10 device. This does not happen when using the simulator. This happens in all projects, including those just created.

libsystem_kernel.dylib`mach_msg_trap: 0x18cfec164 <+0>: movn x16, #0x1e 0x18cfec168 <+4>: svc #0x80 -> 0x18cfec16c <+8>: ret (Thread 1: signal SIGSTOP) 

I have no other iOS devices to test; Does anyone else experience this?

Answer 1

You are not alone - I also come across this. Really annoying. I just registered a bug.

Answer 2

I run Xcode 8.1 with the device - it does not crash, but it hits a breakpoint that you cannot find / edit / delete.

I go to Debug> Continue, and it continues as expected.

Answer 3

GOALS → Features → Background Modes → ON

and check [Audio, AirPlay and picture in picture]

It worked for me.

Answer 4

This is not a failure, something throws a signal to pause the application. Not knowing how the simulated sampling happens, I can only guess why this might be part of the simulation or a side effect of how the application processes it. Xcode is used to constantly block signal breaks (SIGPIPE has always been my mistake), but now it does not work for several versions.