Cannot synthesize weak property

问题：我在使用dsBridge第三方框架时出现。

解决：将下面这段复制到Podfile 的最末尾

post_install do |installer|

     installer.pods_project.targets.each do |target|

          target.build_configurations.each do |config|

               config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = '9.2'

          end

      end

end

相关链接：https://stackoverflow.com/questions/37160688/set-deployment-target-for-cocoapodss-pod