打开旧工程时,报错:

error: -fobjc-arc is not supported on platforms using the legacy runtime

Command /Applications/Xcode 2.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang failed with exit code 1


解决方案:

1.点击工程名—>build settings  

2.找到objective-C Automatic Reference Counting,选择其选项为NO


原因:创建该工程时默认使用开启了ARC