指定真机

    1. xcrun -sdk iphoneos clang -rewrite-objc main.m

    指定模拟器

    1. xcrun -sdk iphonesimulator clang -rewrite-objc main.m

    指定sdk

    1. xcrun -sdk iphonesimulator14.2 clang -rewrite-objc main.m

    将C转C++

    1. clang -rewrite-objc main.c

    查看机器上装有的的sdk

    1.  xcodebuild -showsdks

    引入Framework使用-F

    1. xcrun -sdk iphonesimulator14.2  clang -rewrite-objc -F /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS10.3.platform/Developer/SDKs/iPhoneOS.sdk/System/Library/Frameworks  main.m