Error Compiling with custom swift 5.1.2 toolchain in Xcode

Hi,

I clone and checkout everything related to SWIFT-5.1.2-RELEASE (./utils/update-checkout --clone --tag swift-5.1.2-RELEASE --scheme swift-5.1.2-RELEASE). After that, i generate the toolchain (./utils/build-toolchain BUILD_PREFIX) This took like 3 hours, when finalized i move the .toolchain into ~/Library/Developer/Toolchains and i selected it in xcode.

When i try to compile my project (on xcode with the new toolchain) i get the following:
In Frameworks/NewRelicAgent.framework/NewRelicAgent(json_st.cc.o), archive member 'json_st.cc.o' with length 96528 is not mach-o or llvm bitcode for architecture x86_64
Do you know if i miss something when i build the toolchain?. this doesn't happen with the default xcodeToolchain.

Also, if i create a new xcode project and compile it with the custom toolchain, it will compile and run.

Thanks!

what's the Xcode version and macOS version you used?

I'm seeing a similar issue when using the Swift Toolchain. Haven't found a solution.
"archive member is not mach-o or llvm bitcode for architecture x86_64"

Xcode 11.5, Toolchain of June 9.

Yes, i believe that swift compiler doesn't support xcode 11.5. At least docs and CI Servers says that you need to use 11.4.

Figured it out, in our case we use release configuration for some libs and debug for others. This mismatch caused the warning.