每当我试图Three20在终端中编译一个合并的项目时，我都会收到这个警告。
[exec] /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool : warning for library: /Users/izpulse/IZOHOPULSE_DBUILD/native/ios/Three20/src/Three20/../../Build/Products/Release-iphoneos/libThree20.a the table of contents is empty (no object file members in the library define global symbols)
请问有什么理由吗……？？？？？？