I'm trying to build the package manager using the instruction here under "Using the Trunk Snapshot". When it gets to the stage: --bootstrap: note: building self-hosted 'swift-build'
it throws this error:
.../swift-source/swiftpm: error: manifest parse error(s):
<unknown>:0: error: unknown argument: '-package-description-version'
This happens in this context:
[18/18] Linking CXX CFBundle shared module perftests/Xcode/PerfTests/XcodePerfTests.xctest/Contents/MacOS/XcodePerfTests
--- bootstrap: note: building stage1
--- bootstrap: note: building self-hosted 'swift-build': env SWIFT_EXEC=/../Swift/swift-source/swiftpm/.build/x86_64-apple-macosx/debug/swiftc SWIFTPM_BUILD_DIR=/.../Swift/swift-source/swiftpm/.build SWIFTPM_BOOTSTRAP=1 SDKROOT=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk /.../Swift/swift-source/swiftpm/.build/x86_64-apple-macosx/debug/swift-build-stage1 --disable-sandbox -Xlinker -rpath -Xlinker @executable_path/../lib/swift/macosx -Xswiftc -Xcc -Xswiftc -DSPM_BUILD_IDENT=431e5eea -Xswiftc -I/.../Swift/swift-source/swiftpm/.build/x86_64-apple-macosx/debug/llbuild/products/llbuildSwift -Xswiftc -I/.../Swift/swift-source/swiftpm/../llbuild/products/libllbuild/include -Xlinker -rpath -Xlinker @executable_path/../lib/swift/pm/llbuild -Xlinker -L/./Swift/swift-source/swiftpm/.build/x86_64-apple-macosx/debug/llbuild/lib -Xlinker -rpath -Xlinker /../Swift/swift-source/swiftpm/.build/x86_64-apple-macosx/debug/llbuild/lib --build-tests
/Swift/swift-source/swiftpm: **error:** manifest parse error(s):
<unknown>:0: error: unknown argument: '-package-description-version'
--- bootstrap: error: build failed with exit status 1
What is this error and how do I mitigate it?