1.error: Multiple commands produce 

error: Multiple commands produce '/Users/uesr/Library/Developer/Xcode/DerivedData/OptimalLive-fxatvygbofczeyhjsawtebkimvwx/Build/Products/Debug-iphoneos/OptimalLive.app/Info.plist':

1) Target 'OptimalLive' has copy command from '/Users/uesr/Desktop/workSpace/SEALIVE/SeaLive1.1/OptimalLive/Info.plist' to '/Users/uesr/Library/Developer/Xcode/DerivedData/OptimalLive-fxatvygbofczeyhjsawtebkimvwx/Build/Products/Debug-iphoneos/OptimalLive.app/Info.plist'

2) Target 'OptimalLive' has copy command from '/Users/uesr/Desktop/workSpace/SEALIVE/SeaLive1.1/OptimalLive/Server/Masonry/Info.plist' to '/Users/uesr/Library/Developer/Xcode/DerivedData/OptimalLive-fxatvygbofczeyhjsawtebkimvwx/Build/Products/Debug-iphoneos/OptimalLive.app/Info.plist'

3) Target 'OptimalLive' has process command with input '/Users/uesr/Desktop/workSpace/SEALIVE/SeaLive1.1/OptimalLive/Info.plist'

解决方法：

In Xcode, go to File->Project/Workspace settings.

Change the build system to Legacy Build system.

并没有真正解决问题 而是设置了忽略

2  library not found for -lstdc++.6

xcode10 ios12已经彻底没有这个lib了

直接去xcode9找到这-lstdc++.6.0.9 添加进去

 真机运行库

在终端输入以下命令打开Xcode的lib库目录（此目录位安装的默认目录）

open /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk/usr/lib

如果安装在其他目录 或者Xcode改名的建议右键Xcode显示报内容，进入

Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk/usr/lib

把刚刚下载的zip文件解压

获取到的 真机的 libstdc++.6.0.9.tbd 文件，扔进去

模拟器运行库

在终端输入以下命令打开Xcode的lib库目录（此目录位安装的默认目录）

open  /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/usr/lib

如果安装在其他目录 或者Xcode改名的建议右键Xcode显示报内容，进入

Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/usr/lib                

然后

复制一 份libstdc++.6.0.9.tbz 重命名为 libstdc++.6 两个都保留在路径中

 libstdc++.6.0.9.tbd

运行项目就ok了。

[**百度云链接：stdc++.6.0.9**](https://pan.baidu.com/s/1zCagMy42HGPdZj8XMfOf_Q)