On Wed, Sep 1, 2021 at 9:00 PM Neutron <[email protected]> wrote: > > I've tried running wireguard-apple on an iOS simulator and encountered some > trouble during the compilation of WireGuardKitGo. I did this on an Apple M1, > which I thought at first would be the culprit. > > The Go version is "go1.16 darwin/arm64". The build process fails at > # runtime/cgo > Undefined symbols for architecture arm64: > "_darwin_arm_init_mach_exception_handler", referenced from: > _x_cgo_init in _x004.o > "_darwin_arm_init_thread_exception_port", referenced from: > _threadentry in _x004.o > _x_cgo_init in _x004.o > ld: symbol(s) not found for architecture arm64 > > This issue was reported a few times in Go's issues section, e.g., > https://github.com/golang/go/issues/45772#issuecomment-874616905 > > Further head banging lead me to the discovery that > > xcodebuild -target WireGuardiOS -sdk iphoneos14.5
Yeah, whenever you start seeing problems with missing symbols related to exception handlers, you should look at the target SDK. I see it a lot when trying to cross compile for Apple WatchOS and AppleTV when using the wrong SDK. Besides -sdk, other ones to look for are -miphoneos-version-min, -miphonesimulator-version-min, -mappletvos-version-min, -mappletvsimulator-version-min, -mwatchos-version-min and -mwatchsimulator-version-min. If you drop them too low, you will break during link with the missing exception handlers. I think what happens is, the headers mostly work with a lot of different targets. But the exception handlers are specific to a particular SDK, and you only have a limited range of them installed (otherwise, you have to install older versions of Xcode and older SDKs). I don't know how Go affects things. I usually work with native C/C++/ObjC code. > I don't have an actual iPhone on hand at the moment, > so I guess the question is, is the project supposed to > work only on real hardware? Was that flag left out > intentionally? If so, is there a way to get it to run > properly on simulators? In the past, the network stack was crippled on the simulator. I don't know if that's the case nowadays. I think Android is about the same. It is hard to test some of this stuff on a simulator or emulator. Jeff
