在bash中输入（zsh不行！）
srcdir="/Applications/Xcode.app"
destdir="/Applications/Xcode-beta.app"
files="./Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk/usr/lib/libstdc++*.tbd
./Contents/Developer/Platforms/iPhoneOS.platform/Developer/Library/CoreSimulator/Profiles/Runtimes/iOS.simruntime/Contents/Resources/RuntimeRoot/usr/lib/libstdc++*.dylib
./Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/lib/libstdc++*.tbd
./Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/usr/lib/libstdc++*.tbd"
for i in $files; do
cp -n $srcdir/$i $destdir/$i
done
