Build fails with “Command failed with a nonzero exit code”

Question

When I try to build my app with Xcode, an error interrupts the build process:

Command CompileStoryboard failed with a nonzero exit code

Answer 1

In my case, I used too complicated initializations inside a class extension. It suddenly broke my build.

class MyClass { }
extension MyClass {
static var  var1 = "", var2 = "", var3 = "", var4 = "", ...., var20 = ""
}

Resolved:

class MyClass { }
    extension MyClass {
    static var var1 = "",
    static var var2 = "",
    static var var3 = ""
    static var var4 = "", ...., 
    static var var20 = ""
    }