Swift Command Plugin fails when a dependency is being linked dynamically

Development Package Manager
1

I have the following structure:

command-plugin-dynamic-linking/
├── Package.swift                           # Main package manifest
├── Sources/
│   └── Core/
│       └── Core.swift                      # Executable target that uses DynamicLib
├── Plugins/
│   └── command-plugin-dynamic-linking.swift # Swift Package Manager command plugin
├── LocalPackages/
│   ├── Client/
│   │   ├── Package.swift
│   │   └── Sources/
│   │       └── main.swift
│   └── DynamicLib/
│       ├── Package.swift
│       ├── Sources/
│       │   └── DynamicLib/
│       │       └── DynamicLib.swift        # Dynamic library implementation
│       └── Tests/
│           └── DynamicLibTests/
│               └── DynamicLibTests.swift
└── README.md

Running swift package command_plugin_dynamic_linking inside the `Client` package gives the following error:

Building for debugging...
error: link command failed with exit code 1 (use -v to see invocation)
ld: library 'DynamicLib' not found
clang: error: linker command failed with exit code 1 (use -v to see invocation)
[11/13] Linking Core-tool
error: fatalError

If we run ls .build/arm64-apple-macosx/debug we can see the following output:

Client.build                        Core.build                          DynamicLib.build                    ModuleCache
Core-tool-entitlement.plist         description.json                    index                               Modules-tool
Core-tool.build                     DynamicLib-tool.build               libDynamicLib-tool.dylib            plugin-tools-description.json
Core-tool.product                   DynamicLib-tool.product             libDynamicLib-tool.dylib.dSYM       swift-version--58304C5D6DBC2206.txt

For some reason the DynamicLib is being built as libDynamicLib-tool.dylib but the compiler is searching for libDynamicLib.dylib and thus we get the mentioned error.

A workaround is to copy the libDynamicLib-tool.dylib and to name it libDynamicLib.dylib with the following command:

cp .build/arm64-apple-macosx/debug/libDynamicLib-tool.dylib .build/arm64-apple-macosx/debug/libDynamicLib.dylib

Now when we run swift package command_plugin_dynamic_linking everything works.

Did anyone encounter anything similiar?

The repository reproducing this issue can be found here: GitHub - supersonicbyte/command-plugin-dynamic-linking.

GitHub issue: Command plugin with dynamically linked dependencies fails · Issue #9062 · swiftlang/swift-package-manager · GitHub

2

made a PR: fix linker flags for dynamic libraries when executing command plugin by supersonicbyte · Pull Request #9091 · swiftlang/swift-package-manager · GitHub

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