protoc-gen-swift cannot load SwiftProtobuf library when using SwiftProtobufPlugin in release mode

[MikeWalrus]

The plugin works without issue when the build scheme is set to debug mode, but when doing a release build, protoc cannot find SwiftProtobuf when loading protoc-gen-swift:

dyld[57698]: Library not loaded: @rpath/SwiftProtobuf.framework/Versions/A/SwiftProtobuf

The log shows that in debug mode, protoc-gen-swift is compiled with

cd /Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/SourcePackages/checkouts/swift-protobuf
    /Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang -Xlinker -reproducible -target arm64-apple-macos10.13 -isysroot /Applications/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.2.sdk -O0 -w -L/Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Intermediates.noindex/EagerLinkingTBDs/Debug -L/Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Products/Debug -L/Applications/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib -F/Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Intermediates.noindex/EagerLinkingTBDs/Debug -F/Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Products/Debug/PackageFrameworks -F/Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Products/Debug/PackageFrameworks -F/Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Products/Debug -F/Applications/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/Library/Frameworks -iframework /Applications/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/Library/Frameworks -filelist /Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Intermediates.noindex/SwiftProtobuf.build/Debug/protoc-gen-swift.build/Objects-normal/arm64/protoc-gen-swift.LinkFileList -Xlinker -rpath -Xlinker /usr/lib/swift -Xlinker -rpath -Xlinker /Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Products/Debug/PackageFrameworks -Xlinker -object_path_lto -Xlinker /Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Intermediates.noindex/SwiftProtobuf.build/Debug/protoc-gen-swift.build/Objects-normal/arm64/protoc-gen-swift_lto.o -Xlinker -export_dynamic -Xlinker -no_deduplicate -fobjc-link-runtime -L/Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/macosx -L/usr/lib/swift -Xlinker -add_ast_path -Xlinker /Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Intermediates.noindex/SwiftProtobuf.build/Debug/protoc-gen-swift.build/Objects-normal/arm64/protoc_gen_swift.swiftmodule -Wl,-no_warn_duplicate_libraries -Wl,-no_warn_duplicate_libraries -framework SwiftProtobuf -framework SwiftProtobufPluginLibrary -Xlinker -dependency_info -Xlinker /Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Intermediates.noindex/SwiftProtobuf.build/Debug/protoc-gen-swift.build/Objects-normal/arm64/protoc-gen-swift_dependency_info.dat -o /Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Products/Debug/protoc-gen-swift

But in release mode, it misses the rpath argument:

/Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang -Xlinker -reproducible -target arm64-apple-macos10.13 -isysroot /Applications/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.2.sdk -Os -w -L/Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Intermediates.noindex/EagerLinkingTBDs/Release -L/Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Products/Release -L/Applications/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib -F/Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Intermediates.noindex/EagerLinkingTBDs/Release -F/Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Products/Release/PackageFrameworks -F/Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Products/Release/PackageFrameworks -F/Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Products/Release -F/Applications/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/Library/Frameworks -iframework /Applications/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/Library/Frameworks -filelist /Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Intermediates.noindex/SwiftProtobuf.build/Release/protoc-gen-swift.build/Objects-normal/arm64/protoc-gen-swift.LinkFileList -Xlinker -rpath -Xlinker /usr/lib/swift -Xlinker -object_path_lto -Xlinker /Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Intermediates.noindex/SwiftProtobuf.build/Release/protoc-gen-swift.build/Objects-normal/arm64/protoc-gen-swift_lto.o -Xlinker -debug_variant -fobjc-link-runtime -fprofile-instr-generate -L/Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/macosx -L/usr/lib/swift -Xlinker -add_ast_path -Xlinker /Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Intermediates.noindex/SwiftProtobuf.build/Release/protoc-gen-swift.build/Objects-normal/arm64/protoc_gen_swift.swiftmodule -Wl,-no_warn_duplicate_libraries -Wl,-no_warn_duplicate_libraries -framework SwiftProtobuf -framework SwiftProtobufPluginLibrary -Xlinker -dependency_info -Xlinker /Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Intermediates.noindex/SwiftProtobuf.build/Release/protoc-gen-swift.build/Objects-normal/arm64/protoc-gen-swift_dependency_info.dat -o /Users/test/Library/Developer/Xcode/DerivedData/PaperPilot-cyqhgfgkjjzzwchgmxwnwngxtkbw/Build/Intermediates.noindex/SwiftProtobuf.build/Release/protoc-gen-swift.build/Objects-normal/arm64/Binary/protoc-gen-swift

I can reproduce this on Xcode 15.0 and 15.1 beta, with swift-protobuf 1.25.1.

[thomasvl]

Since we haven't gotten any other reports, I'm guessing this is something unique to your set up? Can you provide more detailed information about you builds? Given the snippets you included, it doesn't sound like you are using SwiftPM to build the plugin? What are the exact steps you are using? Then someone might have some ideas.

[MikeWalrus]

I'm just using the spm-plugin in Xcode following the instructions outlined in Sources/protoc-gen-swift/Docs.docc/spm-plugin.md.

[FranzBusch]

This sounds like an SPM/Xcode problem. Would you mind filing a feedback using the feedback assistant and share the feedback number with me. I don't think there is anything that SwiftProtobuf can do here.

[LSX-s-Software]

I'm a collaborator with MikeWalrus. I have submitted the feedback FB13402398.

[FranzBusch]

It looks like you are building SwiftProtobuf into an a framework. I assume this is where this problem comes from. Make sure to attach a reproducer Xcode project to your feedback.

[Lutzifer]

I'm running into the very same problem, it doesn't seem to be that unique.

[thomasvl]

Closing this since it seems the issues here are with Xcode's SwiftPM support and nothing we can do on this project.

[Lutzifer]

For me this disappeared after reducing the dependencies inside the project to a minimum, i.e. avoiding to depend on Protobuf (or GRPC) multiple times

[Lutzifer]

I can confirm that this issue still exists and my solution for it still works (came here as I had the issue on another project)

[ethanndickson]

For me this disappeared after reducing the dependencies inside the project to a minimum, i.e. avoiding to depend on Protobuf (or GRPC) multiple times

Very helpful. Thank you. I can confirm this still happens.