Unable to build trunk SwiftPM with compiler built with Xcode 26.4

[finagolfin]

Is it reproducible with SwiftPM command-line tools: swift build, swift test, swift package etc?

• Confirmed reproduction steps with SwiftPM CLI. The description text must include reproduction steps with either of command-line SwiftPM commands, swift build, swift test, swift package etc.

Description

I first built the release no-asserts compiler from a recent Mar. 30 commit and ran the compiler validation suite:

./swift/utils/build-script -RA --skip-build-benchmarks --swift-darwin-supported-archs "arm64" --swift-disable-dead-stripping -T

Then, I tried to build and test SwiftPM:

./swift/utils/build-script -RA --skip-build-benchmarks --swift-darwin-supported-archs "arm64" --swift-disable-dead-stripping -T --skip-test-swift --install-llvm --install-swift --swift-testing-macros --swift-testing --install-swift-testing-macros --install-swift-testing -b -p

That command consistently fails at this step when trying to build the tests for SwiftPM:

Failed frontend command:
/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift-frontend -frontend -c /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/DerivedSources/test_entry_point.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/CanonicalPackageLocationTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/EnabledTraitTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/InstalledSwiftPMConfigurationTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/ManifestTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/MinimumDeploymentTargetTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/PackageIdentityNameTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/PackageIdentityParser.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/PackageIdentityScopeTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/PackageModelTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/PlatformConditionTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/SnippetTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/SwiftLanguageVersionTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/SwiftSDKBundleTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/SwiftSDKTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/ToolsVersionTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/ToolsetTests.swift -supplementary-output-file-map /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/supplementaryOutputs-57 -target arm64-apple-macos14.0 -module-can-import-version Darwin 377.100.15 0 -module-can-import Testing -module-can-import-version XCTest 24833 0 -load-resolved-plugin /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib/swift/host/plugins/libFoundationMacros.dylib\#/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/bin/swift-plugin-server\#FoundationMacros -load-resolved-plugin /Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/host/plugins/libObservationMacros.dylib\#\#ObservationMacros -load-resolved-plugin /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib/swift/host/plugins/libPreviewsMacros.dylib\#/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/bin/swift-plugin-server\#PreviewsMacros -load-resolved-plugin /Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/host/plugins/libSwiftMacros.dylib\#\#SwiftMacros -load-resolved-plugin /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib/swift/host/plugins/libSwiftUIMacros.dylib\#/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/bin/swift-plugin-server\#SwiftUIMacros -load-resolved-plugin /Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/host/plugins/testing/libTestingMacros.dylib\#/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift-plugin-server\#TestingMacros -disable-implicit-swift-modules -Xcc -fno-implicit-modules -Xcc -fno-implicit-module-maps -explicit-swift-module-map-file /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageModelTests-dependencies-1.json -Xllvm -aarch64-use-tbi -enable-objc-interop -sdk /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX26.4.sdk -I /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release -Isystem /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib -Isystem /Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/macosx/testing -F /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release/PackageFrameworks -F /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release -F /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/Library/Frameworks -module-cache-path /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftExplicitPrecompiledModules -no-color-diagnostics -Xcc -fno-color-diagnostics -enable-testing -g -debug-info-format\=dwarf -dwarf-version\=4 -swift-version 5 -O -D SWIFT_PACKAGE -D Xcode -serialize-debugging-options -enable-experimental-feature DebugDescriptionMacro -empty-abi-descriptor -validate-clang-modules-once -clang-build-session-file /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/ModuleCache.noindex/Session.modulevalidation -Xcc -working-directory -Xcc /Users/finagolfin/swift -file-compilation-dir /Users/finagolfin/swift -Xcc -fmodule-map-file\=/Users/finagolfin/swift/swift-system/Sources/CSystem/include/module.modulemap -Xcc -fmodule-map-file\=/Users/finagolfin/swift/swift-driver/Sources/CSwiftScan/include/module.modulemap -Xcc -fmodule-map-file\=/Users/finagolfin/swift/swift-crypto/Sources/CCryptoBoringSSLShims/include/module.modulemap -Xcc -fmodule-map-file\=/Users/finagolfin/swift/swift-crypto/Sources/CCryptoBoringSSL/include/module.modulemap -Xcc -fmodule-map-file\=/Users/finagolfin/swift/swift-tools-support-core/Sources/TSCclibc/include/module.modulemap -Xcc -fmodule-map-file\=/Users/finagolfin/swift/swiftpm/Sources/SPMSQLite3/module.modulemap -Xcc -fmodules-prune-interval\=86400 -Xcc -fmodules-prune-after\=345600 -Xcc -I/Users/finagolfin/swift/swift-system/Sources/CSystem/include -Xcc -I/Users/finagolfin/swift/swift-driver/Sources/CSwiftScan/include -Xcc -I/Users/finagolfin/swift/swift-crypto/Sources/CCryptoBoringSSLShims/include -Xcc -I/Users/finagolfin/swift/swift-crypto/Sources/CCryptoBoringSSL/include -Xcc -I/Users/finagolfin/swift/swift-tools-support-core/Sources/TSCclibc/include -Xcc -I/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release/include -Xcc -I/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/DerivedSources-normal/arm64 -Xcc -I/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/DerivedSources/arm64 -Xcc -I/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/DerivedSources -Xcc -DSWIFT_PACKAGE -no-auto-bridging-header-chaining -module-name PackageModelTests -package-name swiftpm -const-gather-protocols-file /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageModelTests_const_extract_protocols.json -in-process-plugin-server-path /Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/host/libSwiftInProcPluginServer.dylib -clang-target arm64-apple-macos26.4 -target-sdk-version 26.4 -target-sdk-name macosx26.4 -enable-default-cmo -parse-as-library -num-threads 10 -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/test_entry_point.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/CanonicalPackageLocationTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/EnabledTraitTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/InstalledSwiftPMConfigurationTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/ManifestTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/MinimumDeploymentTargetTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageIdentityNameTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageIdentityParser.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageIdentityScopeTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageModelTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PlatformConditionTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SnippetTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SwiftLanguageVersionTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SwiftSDKBundleTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SwiftSDKTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/ToolsVersionTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/ToolsetTests.o -debug-module-path /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageModelTests.swiftmodule -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/test_entry_point.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/CanonicalPackageLocationTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/EnabledTraitTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/InstalledSwiftPMConfigurationTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/ManifestTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/MinimumDeploymentTargetTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageIdentityNameTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageIdentityParser.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageIdentityScopeTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageModelTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PlatformConditionTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SnippetTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SwiftLanguageVersionTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SwiftSDKBundleTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SwiftSDKTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/ToolsVersionTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/ToolsetTests.o
error: Ld /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release/PackagePluginAPITests.xctest/Contents/MacOS/PackagePluginAPITests normal failed with a nonzero exit code. Command line:     cd /Users/finagolfin/swift/swiftpm
    /Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc -Xlinker -reproducible -target arm64-apple-macos14.0 -Xlinker -bundle -sdk /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX26.4.sdk -L/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/EagerLinkingTBDs/Release -L/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release -L/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib -L/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/macosx/testing -F/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/EagerLinkingTBDs/Release -F/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release/PackageFrameworks -F/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release -Fsystem /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/Library/Frameworks @/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackagePluginAPITests-p.build/Objects-normal/arm64/PackagePluginAPITests.LinkFileList -Xlinker -rpath -Xlinker /usr/lib/swift -Xlinker -rpath -Xlinker @loader_path -Xlinker -rpath -Xlinker @loader_path/Frameworks -Xlinker -rpath -Xlinker @loader_path/../Frameworks -Xlinker -rpath -Xlinker /Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift-6.2/macosx -Xlinker -rpath -Xlinker /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift-6.2/macosx -Xlinker -dead_strip -Xlinker -object_path_lto -Xlinker /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackagePluginAPITests-p.build/Objects-normal/arm64/PackagePluginAPITests_lto.o -Xclang-linker -rdynamic -Xlinker -dependency_info -Xlinker /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackagePluginAPITests-p.build/Objects-normal/arm64/PackagePluginAPITests_dependency_info.dat -link-objc-runtime -L/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/macosx -L/usr/lib/swift -Xlinker -add_ast_path -Xlinker /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackagePluginAPITests-p.build/Objects-normal/arm64/PackagePluginAPITests.swiftmodule -lc++ -module-cache-path /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/module-cache -Xlinker -needed_framework -Xlinker XCTest -framework XCTest -Xlinker -needed-lXCTestSwiftSupport -lXCTestSwiftSupport -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release/PackagePluginAPITests.xctest/Contents/MacOS/PackagePluginAPITests -no-stdlib-rpath

-- snip a bunch of warnings ---

error: Build failed
error: fatalError
--- bootstrap | 2026-04-01 23:40:41,970 | ERROR   | MainThread | helpers | call | Line:73 | Process failure with return code 1: Command '['env', 'SDKROOT=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX26.4.sdk', 'SWIFTCI_USE_LOCAL_DEPS=1', 'SWIFTPM_MACOS_DEPLOYMENT_TARGET=14.0', 'DYLD_LIBRARY_PATH=/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/bootstrap/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/tsc/lib:/Users/finagolfin/swift/build/Ninja-Release/llbuild-macosx-arm64/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-argument-parser/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-crypto/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-driver/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-system/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-collections/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-tools-protocols/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-asn1/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-certificates/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-build/lib', 'SWIFTCI_DISABLE_SDK_DEPENDENT_TESTS=YES', 'SWIFT_EXEC=/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc', 'SWIFT_DRIVER_SWIFT_EXEC=/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc', 'CC=/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release/swift-test', '--parallel', '--build-path', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64', '--configuration', 'release', '--arch', 'arm64', '-Xswiftc', '-module-cache-path', '-Xswiftc', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/module-cache', '-Xbuild-tools-swiftc', '-module-cache-path', '-Xbuild-tools-swiftc', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/module-cache']' returned non-zero exit status 1.
[---- START stdout ----]
None
[---- END stdout ----]
[---- START stderr ----]
None
[---- END stderr ----]
[---- START OUTPUT ----]
None
[---- END OUTPUT ----]
Traceback (most recent call last):
  File "/Users/finagolfin/swift/swiftpm/Utilities/bootstrap", line 965, in <module>
    main()
  File "/Users/finagolfin/swift/swiftpm/Utilities/bootstrap", line 62, in wrapper
    return func(*args, **kwargs)
  File "/Users/finagolfin/swift/swiftpm/Utilities/bootstrap", line 102, in main
    args.func(args)
  File "/Users/finagolfin/swift/swiftpm/Utilities/bootstrap", line 62, in wrapper
    return func(*args, **kwargs)
  File "/Users/finagolfin/swift/swiftpm/Utilities/bootstrap", line 442, in test
    call_swiftpm(args, cmd)
  File "/Users/finagolfin/swift/swiftpm/Utilities/bootstrap", line 62, in wrapper
    return func(*args, **kwargs)
  File "/Users/finagolfin/swift/swiftpm/Utilities/bootstrap", line 808, in call_swiftpm
    call(full_cmd, cwd=cwd)
  File "/Users/finagolfin/swift/swiftpm/Utilities/helpers.py", line 92, in call
    raise cpe
  File "/Users/finagolfin/swift/swiftpm/Utilities/helpers.py", line 70, in call
    subprocess.check_call(cmd, cwd=cwd)
  File "/Applications/Xcode.app/Contents/Developer/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/subprocess.py", line 373, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['env', 'SDKROOT=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX26.4.sdk', 'SWIFTCI_USE_LOCAL_DEPS=1', 'SWIFTPM_MACOS_DEPLOYMENT_TARGET=14.0', 'DYLD_LIBRARY_PATH=/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/bootstrap/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/tsc/lib:/Users/finagolfin/swift/build/Ninja-Release/llbuild-macosx-arm64/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-argument-parser/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-crypto/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-driver/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-system/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-collections/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-tools-protocols/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-asn1/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-certificates/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-build/lib', 'SWIFTCI_DISABLE_SDK_DEPENDENT_TESTS=YES', 'SWIFT_EXEC=/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc', 'SWIFT_DRIVER_SWIFT_EXEC=/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc', 'CC=/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release/swift-test', '--parallel', '--build-path', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64', '--configuration', 'release', '--arch', 'arm64', '-Xswiftc', '-module-cache-path', '-Xswiftc', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/module-cache', '-Xbuild-tools-swiftc', '-module-cache-path', '-Xbuild-tools-swiftc', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/module-cache']' returned non-zero exit status 1.
ERROR: command `['/Users/finagolfin/swift/swiftpm/Utilities/bootstrap', 'test', '--release', '--swiftc-path', '/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc', '--clang-path', '/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang', '--cmake-path', '/usr/local/bin/cmake', '--ninja-path', '/Users/finagolfin/.swiftly/bin/ninja', '--build-dir', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64', '--llbuild-build-dir', '/Users/finagolfin/swift/build/Ninja-Release/llbuild-macosx-arm64']` terminated with a non-zero exit status 1, aborting

The reported error: Ld makes me think the issue is with the new Xcode, as I had no problem building with a prior Xcode and a Mar. 18 trunk source checkout the last couple weeks. Of course, that previous commit was not using the new swift-build backend either.

Expected behavior

The SwiftPM tests to build

Actual behavior

Strange compilation failures

Steps to reproduce

See the commands above

Swift Package Manager version/commit hash

b8277bc with #9229 applied

Swift & OS version (output of swift --version ; uname -a)

> ../build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift -version
Swift version 6.4-dev (LLVM 9ca1419285d601e, Swift b866471e8c03512)
Target: arm64-apple-macosx26.0
> uname -a
Darwin Fin.local 25.4.0 Darwin Kernel Version 25.4.0: Thu Mar 19 19:31:09 PDT 2026; root:xnu-12377.101.15~1/RELEASE_ARM64_T8132 arm64

[finagolfin]

I neglected to mention that the Swift portions of the trunk Swift compiler above were built with the prebuilt OSS Swift 6.3.0 compiler installed through swiftly, unsure if that affects this also.

[finagolfin]

I tried switching the prebuilt host compiler over to the Xcode one, still failing with a similar error:

Failed frontend command:
/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift-frontend -frontend -c /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/DerivedSources/test_entry_point.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/CanonicalPackageLocationTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/EnabledTraitTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/InstalledSwiftPMConfigurationTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/ManifestTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/MinimumDeploymentTargetTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/PackageIdentityNameTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/PackageIdentityParser.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/PackageIdentityScopeTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/PackageModelTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/PlatformConditionTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/SnippetTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/SwiftLanguageVersionTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/SwiftSDKBundleTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/SwiftSDKTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/ToolsVersionTests.swift /Users/finagolfin/swift/swiftpm/Tests/PackageModelTests/ToolsetTests.swift -supplementary-output-file-map /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/supplementaryOutputs-57 -target arm64-apple-macos14.0 -module-can-import-version Darwin 377.100.15 0 -module-can-import Testing -module-can-import-version XCTest 24833 0 -load-resolved-plugin /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib/swift/host/plugins/libFoundationMacros.dylib\#/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/bin/swift-plugin-server\#FoundationMacros -load-resolved-plugin /Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/host/plugins/libObservationMacros.dylib\#\#ObservationMacros -load-resolved-plugin /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib/swift/host/plugins/libPreviewsMacros.dylib\#/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/bin/swift-plugin-server\#PreviewsMacros -load-resolved-plugin /Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/host/plugins/libSwiftMacros.dylib\#\#SwiftMacros -load-resolved-plugin /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib/swift/host/plugins/libSwiftUIMacros.dylib\#/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/bin/swift-plugin-server\#SwiftUIMacros -load-resolved-plugin /Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/host/plugins/testing/libTestingMacros.dylib\#/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift-plugin-server\#TestingMacros -disable-implicit-swift-modules -Xcc -fno-implicit-modules -Xcc -fno-implicit-module-maps -explicit-swift-module-map-file /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageModelTests-dependencies-1.json -Xllvm -aarch64-use-tbi -enable-objc-interop -sdk /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX26.4.sdk -I /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release -Isystem /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib -Isystem /Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/macosx/testing -F /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release/PackageFrameworks -F /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release -F /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/Library/Frameworks -module-cache-path /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftExplicitPrecompiledModules -no-color-diagnostics -Xcc -fno-color-diagnostics -enable-testing -g -debug-info-format\=dwarf -dwarf-version\=4 -swift-version 5 -O -D SWIFT_PACKAGE -D Xcode -serialize-debugging-options -enable-experimental-feature DebugDescriptionMacro -empty-abi-descriptor -validate-clang-modules-once -clang-build-session-file /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/ModuleCache.noindex/Session.modulevalidation -Xcc -working-directory -Xcc /Users/finagolfin/swift -file-compilation-dir /Users/finagolfin/swift -Xcc -fmodule-map-file\=/Users/finagolfin/swift/swift-system/Sources/CSystem/include/module.modulemap -Xcc -fmodule-map-file\=/Users/finagolfin/swift/swift-driver/Sources/CSwiftScan/include/module.modulemap -Xcc -fmodule-map-file\=/Users/finagolfin/swift/swift-crypto/Sources/CCryptoBoringSSLShims/include/module.modulemap -Xcc -fmodule-map-file\=/Users/finagolfin/swift/swift-crypto/Sources/CCryptoBoringSSL/include/module.modulemap -Xcc -fmodule-map-file\=/Users/finagolfin/swift/swift-tools-support-core/Sources/TSCclibc/include/module.modulemap -Xcc -fmodule-map-file\=/Users/finagolfin/swift/swiftpm/Sources/SPMSQLite3/module.modulemap -Xcc -fmodules-prune-interval\=86400 -Xcc -fmodules-prune-after\=345600 -Xcc -I/Users/finagolfin/swift/swift-system/Sources/CSystem/include -Xcc -I/Users/finagolfin/swift/swift-driver/Sources/CSwiftScan/include -Xcc -I/Users/finagolfin/swift/swift-crypto/Sources/CCryptoBoringSSLShims/include -Xcc -I/Users/finagolfin/swift/swift-crypto/Sources/CCryptoBoringSSL/include -Xcc -I/Users/finagolfin/swift/swift-tools-support-core/Sources/TSCclibc/include -Xcc -I/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release/include -Xcc -I/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/DerivedSources-normal/arm64 -Xcc -I/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/DerivedSources/arm64 -Xcc -I/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/DerivedSources -Xcc -DSWIFT_PACKAGE -no-auto-bridging-header-chaining -module-name PackageModelTests -package-name swiftpm -const-gather-protocols-file /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageModelTests_const_extract_protocols.json -in-process-plugin-server-path /Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/host/libSwiftInProcPluginServer.dylib -clang-target arm64-apple-macos26.4 -target-sdk-version 26.4 -target-sdk-name macosx26.4 -enable-default-cmo -parse-as-library -num-threads 10 -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/test_entry_point.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/CanonicalPackageLocationTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/EnabledTraitTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/InstalledSwiftPMConfigurationTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/ManifestTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/MinimumDeploymentTargetTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageIdentityNameTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageIdentityParser.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageIdentityScopeTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageModelTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PlatformConditionTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SnippetTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SwiftLanguageVersionTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SwiftSDKBundleTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SwiftSDKTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/ToolsVersionTests.o -o /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/ToolsetTests.o -debug-module-path /Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Intermediates.noindex/SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageModelTests.swiftmodule -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/test_entry_point.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/CanonicalPackageLocationTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/EnabledTraitTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/InstalledSwiftPMConfigurationTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/ManifestTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/MinimumDeploymentTargetTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageIdentityNameTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageIdentityParser.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageIdentityScopeTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PackageModelTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/PlatformConditionTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SnippetTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SwiftLanguageVersionTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SwiftSDKBundleTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/SwiftSDKTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/ToolsVersionTests.o -index-unit-output-path /SwiftPM.build/Release/PackageModelTests-p.build/Objects-normal/arm64/ToolsetTests.o

--- snip unrelated warnings ---

error: Build failed
error: fatalError
--- bootstrap | 2026-04-03 19:34:31,357 | ERROR   | MainThread | helpers | call | Line:73 | Process failure with return code 1: Command '['env', 'SDKROOT=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX26.4.sdk', 'SWIFTCI_USE_LOCAL_DEPS=1', 'SWIFTPM_MACOS_DEPLOYMENT_TARGET=14.0', 'DYLD_LIBRARY_PATH=/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/bootstrap/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/tsc/lib:/Users/finagolfin/swift/build/Ninja-Release/llbuild-macosx-arm64/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-argument-parser/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-crypto/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-driver/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-system/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-collections/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-tools-protocols/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-asn1/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-certificates/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-build/lib', 'SWIFTCI_DISABLE_SDK_DEPENDENT_TESTS=YES', 'SWIFT_EXEC=/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc', 'SWIFT_DRIVER_SWIFT_EXEC=/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc', 'CC=/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release/swift-test', '--parallel', '--build-path', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64', '--configuration', 'release', '--arch', 'arm64', '-Xswiftc', '-module-cache-path', '-Xswiftc', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/module-cache', '-Xbuild-tools-swiftc', '-module-cache-path', '-Xbuild-tools-swiftc', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/module-cache']' returned non-zero exit status 1.
[---- START stdout ----]
None
[---- END stdout ----]
[---- START stderr ----]
None
[---- END stderr ----]
[---- START OUTPUT ----]
None
[---- END OUTPUT ----]
Traceback (most recent call last):
  File "/Users/finagolfin/swift/swiftpm/Utilities/bootstrap", line 965, in <module>
    main()
  File "/Users/finagolfin/swift/swiftpm/Utilities/bootstrap", line 62, in wrapper
    return func(*args, **kwargs)
  File "/Users/finagolfin/swift/swiftpm/Utilities/bootstrap", line 102, in main
    args.func(args)
  File "/Users/finagolfin/swift/swiftpm/Utilities/bootstrap", line 62, in wrapper
    return func(*args, **kwargs)
  File "/Users/finagolfin/swift/swiftpm/Utilities/bootstrap", line 442, in test
    call_swiftpm(args, cmd)
  File "/Users/finagolfin/swift/swiftpm/Utilities/bootstrap", line 62, in wrapper
    return func(*args, **kwargs)
  File "/Users/finagolfin/swift/swiftpm/Utilities/bootstrap", line 808, in call_swiftpm
    call(full_cmd, cwd=cwd)
  File "/Users/finagolfin/swift/swiftpm/Utilities/helpers.py", line 92, in call
    raise cpe
  File "/Users/finagolfin/swift/swiftpm/Utilities/helpers.py", line 70, in call
    subprocess.check_call(cmd, cwd=cwd)
  File "/Applications/Xcode.app/Contents/Developer/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/subprocess.py", line 373, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['env', 'SDKROOT=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX26.4.sdk', 'SWIFTCI_USE_LOCAL_DEPS=1', 'SWIFTPM_MACOS_DEPLOYMENT_TARGET=14.0', 'DYLD_LIBRARY_PATH=/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/bootstrap/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/tsc/lib:/Users/finagolfin/swift/build/Ninja-Release/llbuild-macosx-arm64/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-argument-parser/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-crypto/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-driver/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-system/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-collections/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-tools-protocols/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-asn1/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-certificates/lib:/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/swift-build/lib', 'SWIFTCI_DISABLE_SDK_DEPENDENT_TESTS=YES', 'SWIFT_EXEC=/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc', 'SWIFT_DRIVER_SWIFT_EXEC=/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc', 'CC=/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/out/Products/Release/swift-test', '--parallel', '--build-path', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64', '--configuration', 'release', '--arch', 'arm64', '-Xswiftc', '-module-cache-path', '-Xswiftc', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/module-cache', '-Xbuild-tools-swiftc', '-module-cache-path', '-Xbuild-tools-swiftc', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64/module-cache']' returned non-zero exit status 1.
ERROR: command `['/Users/finagolfin/swift/swiftpm/Utilities/bootstrap', 'test', '--release', '--swiftc-path', '/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc', '--clang-path', '/Users/finagolfin/swift/build/Ninja-Release/toolchain-macosx-arm64/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang', '--cmake-path', '/usr/local/bin/cmake', '--ninja-path', '/Users/finagolfin/.swiftly/bin/ninja', '--build-dir', '/Users/finagolfin/swift/build/Ninja-Release/swiftpm-macosx-arm64', '--llbuild-build-dir', '/Users/finagolfin/swift/build/Ninja-Release/llbuild-macosx-arm64']` terminated with a non-zero exit status 1, aborting

@owenv, are we not supposed to use the new Xcode 26.4 to compile the trunk toolchain yet?

[owenv]

@finagolfin I would expect this to work, although I'm not often developing with Xcode 26.4 in the context of a fully bootstrapped build. If you re-run the failed frontend command standalone, does it emit any additional output or produce a crashlog?

[finagolfin]

I'll try that and going back to using OSS Swift 6.2.3 as the bootstrap compiler and let you know what I find this weekend.