what is difference the between "swift clang (in apple opensource )" and "default clang (in xcode)" related to bitcode?

Dear all,

I tried to make the archive of my app that is compiled using swift-clang(opensource : https://github.com/apple/swift-clang )

Making archive of my application is successed, But I can’t upload AppStore.

I received to mail from “App Store Connect”.

The contents of the email are as follows.

“Invaild Bundle - The app cannot be processed because options not allowed to be embedded in bitcode are detected in the submission. It is likely that you are not building the app with the toolchain provided in Xcode. Rebuild your entire app with the latest GM Xcode and submit the app again.”

My environment of compile are as follows.

Xcode version : 9.4.1

Compiler : opensource swift clang (LLVM)

Bitcode : enable

What is difference the between “swift clang (in apple opensource )” and “default clang (in xcode)” related to bitcode?

Please give me a solution.

Thanks

Best regards…