unable to execute command: Segmentation fault: 11 swift frontend command failed due to signal (use -v to see invocation)

Here’s how I was able to find out what the problem was:

1. Click on the issue in the issue navigator (⌘ + 4, then click on the line with the red ! at the start)
2. At the bottom of the file that appears, there should be a line that says something like:

1. While emitting IR SIL function @_TToZFC4Down8Resource12getInstancesfMS0_U__FTSS6paramsGVSs10DictionarySSPSs9AnyObject__9onSuccessGSqFGSaQ__T__7onErrorGSqFT5errorCSo7NSError8responseGSqCSo17NSHTTPURLResponse__T___T_ for 'getInstances' at /path/to/file.swift:112:5

3. The location where your error occurred is at the end of that line. (In this case, on line 112 of file.swift in getInstances).