I have a simple main.swift that looks like this: ``` print("Hello, world!") let x: String? = nil
func say(message: String?) { print(x!) // intentional crash } say(message: x) ``` Running this results in the crash ``` $ swift build && ./.build/debug/hello Hello, world! fatal error: unexpectedly found nil while unwrapping an Optional value Current stack trace: 0 libswiftCore.dylib 0x0000000110120130 swift_reportError + 129 1 libswiftCore.dylib 0x000000011013cb50 _swift_stdlib_reportFatalError + 60 2 libswiftCore.dylib 0x000000010ff2d250 specialized specialized StaticString.withUTF8Buffer<A> ((UnsafeBufferPointer<UInt8>) -> A) -> A + 342 3 libswiftCore.dylib 0x00000001100a7e90 partial apply for (_fatalErrorMessage(StaticString, StaticString, file : StaticString, line : UInt, flags : UInt32) -> Never).(closure #2) + 109 4 libswiftCore.dylib 0x000000010ff2d250 specialized specialized StaticString.withUTF8Buffer<A> ((UnsafeBufferPointer<UInt8>) -> A) -> A + 342 5 libswiftCore.dylib 0x000000011005a9a0 specialized _fatalErrorMessage(StaticString, StaticString, file : StaticString, line : UInt, flags : UInt32) -> Never + 96 6 hello 0x000000010fee6200 main + 345 7 libdyld.dylib 0x00007fffe0375234 start + 1 Illegal instruction: 4 ``` >From the crash, how do I map back line 6 to an actual line in main.swift?
_______________________________________________ swift-users mailing list swift-users@swift.org https://lists.swift.org/mailman/listinfo/swift-users