Updated to Unity 5.6 from 5.4, pbxproject is now invalid?

Unity Engine
,
1

I have a post build process step which fails to load the pbxproject saying “Exception: Invalid PBX project (parsing line 1573)”, this is the block it’s complaining about (I think):

B1B26327752C4F00882016D2 /* ShellScript */ = {
isa = PBXShellScriptBuildPhase;
buildActionMask = 2147483647;
files = (
);
inputPaths = (
);
outputPaths = (
);
runOnlyForDeploymentPostprocessing = 0;
line 1573 —>shellPath = “/bin/sh -x”;

xcode can’t load the project either.

This does not happen in an empty project and the old build works fine.

2

After some investigation I found the cause to be crashlytics, specifically the FabricSettings asset in Assets/Editor Default Resources.

If I delete it an dbuild it the project builds fine…

Now the question is, is this a Unity bug or an issue with the FabricSettings.asset file?