问题1: library not found for -lstdc++.6.0.9
Xcode10把libstdc++给删掉了...
把Xcode9的文件copy过去就好了
cp /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk/usr/lib/libstdc++.* /Applications/Xcode-beta.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk/usr/lib/
cp /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/usr/lib/libstdc++.* /Applications/Xcode-beta.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/usr/lib/
问题2: error: unable to spawn process (Argument list too long)
这应该是Xcode的一个bug,跟项目存放的位置太深有关
把项目放到根路径就好了