-fobjc-weak is not supported on

在项目podfile最后加

post_install do |installer_representation|

    installer_representation.pods_project.targets.each do |target|

        target.build_configurations.each do |config|

            config.build_settings['CLANG_ENABLE_OBJC_WEAK'] ||= 'YES'

            config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = '8.0'

        end

    end

end

然后pod update.