swift：如何从命令行生成arm7或arm64

/Projects/Test $cat main.swift 
print("Hello World!");

编译x86_64

/Projects/Test $swiftc main.swift 
/Projects/Test $lipo -info main
Non-fat file: main is architecture: x86_64
/Projects/Test $./main
Hello World!

编译armv7

/Projects/Test $swiftc main.swift -sdk /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS10.2.sdk -target armv7-apple-ios8.1
/Projects/Test $lipo -info main
Non-fat file: main is architecture: armv7

编译arm64

/Projects/Test $swiftc main.swift -sdk /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS10.2.sdk -target arm64-apple-ios8.1
/Projects/Test $lipo -info main
Non-fat file: main is architecture: arm64

我写了一个脚本build.sh,使其更容易使用：

#!/bin/sh
TARGET_MAC_VERSION=10.11
TARGET_IOS_VERSION=8.1

if [ "$#" -ne 2 ]; then
    echo "Usage $0: <armv7/arm64/x86_64> <file>"
    exit
fi

if [ "$1" != 'armv7' ] && [ "$1" != 'arm64' ] && [ "$1" != 'x86_64' ]; then
  echo "Usage $0: <armv7/arm64/x86_64>"
  exit
fi

if [ "$1" == 'x86_64' ]; then
  SDK=macosx
  TARGET="x86_64-macosx$TARGET_MAC_VERSION"
else
  SDK=iphoneos
  TARGET="$1-apple-ios$TARGET_IOS_VERSION"
fi
echo "xcrun -sdk  $SDK swiftc $2 -target $TARGET"
xcrun -sdk  $SDK swiftc $2 -target $TARGET

产量

$./build.sh armv7 main.swift 
xcrun -sdk  iphoneos swiftc main.swift -target armv7-apple-ios8.1
  $lipo -info main
Non-fat file: main is architecture: armv7
  $./build.sh arm64 main.swift 
xcrun -sdk  iphoneos swiftc main.swift -target arm64-apple-ios8.1
  $lipo -info main
Non-fat file: main is architecture: arm64
  $./build.sh x86_64 main.swift 
xcrun -sdk  macosx swiftc main.swift -target x86_64-macosx10.11
  $lipo -info main
Non-fat file: main is architecture: x86_64

编辑注意：根据@jens的输入优化脚本.有关更多信息,请参阅评论.