将OC代码编译成C++源码，探究底层实现原理

xcrun -sdk iphonesimulator clang -rewrite-objc ViewController.m

clang -x objective-c -rewrite-objc -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator12.1.sdk ViewController.h

最新

 xcrun -sdk iphoneos clang -arch arm64 -rewrite-objc main.m -o -main-arm64