Swift Package Index

Build Information

Failed to build Prelude, reference 0.1.2 (5f0b12), with Swift 6.4 for macOS (SPM) on 17 Sep 2026 22:41:53 UTC.

Build Command

env DEVELOPER_DIR=/Applications/Xcode-27.0.0-Release.Candidate.app xcrun swift build --arch arm64

Build Log

========================================
RunAll
========================================
Builder version: 5.1.0
Interrupt handler set up.
========================================
Checkout
========================================
Clone URL: https://github.com/pointfreeco/swift-prelude.git
Reference: 0.1.2
Initialized empty Git repository in /Users/admin/builder/spi-builder-workspace/.git/
From https://github.com/pointfreeco/swift-prelude
 * tag               0.1.2      -> FETCH_HEAD
HEAD is now at 5f0b128 move add/mult precedence to 6 and 7 (#9)
Cloned https://github.com/pointfreeco/swift-prelude.git
Revision (git rev-parse @):
5f0b128bf620e162d574219d3d45b272f19c8423
SUCCESS checkout https://github.com/pointfreeco/swift-prelude.git at 0.1.2
========================================
Build
========================================
Selected platform:         macosSpm
Swift version:             6.4
Building package at path:  $PWD
https://github.com/pointfreeco/swift-prelude.git
Running build ...
env DEVELOPER_DIR=/Applications/Xcode-27.0.0-Release.Candidate.app xcrun swift build --arch arm64
Building for debugging...
[Planning deferred tasks]
[19 / 28]
[31 / 40] Prelude
error: SwiftCompile normal arm64 failed with a nonzero exit code. Command line:     cd /Users/admin/builder

/Users/admin/builder/spi-builder-workspace/Sources/Prelude/Sequence.swift:33:83: error: 'SubSequence' is not a member type of type 'S'
 31 | }
 32 |
 33 | public func drop<S: Sequence>(while p: @escaping (S.Element) -> Bool) -> (S) -> S.SubSequence {
    |                                                                                   `- error: 'SubSequence' is not a member type of type 'S'
 34 |   return { xs in
 35 |     xs.drop(while: p)
/Users/admin/builder/spi-builder-workspace/Sources/Prelude/Sequence.swift:39:50: error: 'SubSequence' is not a member type of type 'S'
 37 | }
 38 |
 39 | public func dropFirst<S: Sequence>(_ xs: S) -> S.SubSequence {
    |                                                  `- error: 'SubSequence' is not a member type of type 'S'
 40 |   return xs.dropFirst()
 41 | }
/Users/admin/builder/spi-builder-workspace/Sources/Prelude/Sequence.swift:43:58: error: 'SubSequence' is not a member type of type 'S'
 41 | }
 42 |
 43 | public func dropFirst<S: Sequence>(_ n: Int) -> (S) -> S.SubSequence {
    |                                                          `- error: 'SubSequence' is not a member type of type 'S'
 44 |   return { xs in
 45 |     xs.dropFirst(n)
/Users/admin/builder/spi-builder-workspace/Sources/Prelude/Sequence.swift:49:49: error: 'SubSequence' is not a member type of type 'S'
 47 | }
 48 |
 49 | public func dropLast<S: Sequence>(_ xs: S) -> S.SubSequence {
    |                                                 `- error: 'SubSequence' is not a member type of type 'S'
 50 |   return xs.dropLast()
 51 | }
/Users/admin/builder/spi-builder-workspace/Sources/Prelude/Sequence.swift:53:57: error: 'SubSequence' is not a member type of type 'S'
 51 | }
 52 |
 53 | public func dropLast<S: Sequence>(_ n: Int) -> (S) -> S.SubSequence {
    |                                                         `- error: 'SubSequence' is not a member type of type 'S'
 54 |   return { xs in
 55 |     xs.dropLast(n)
/Users/admin/builder/spi-builder-workspace/Sources/Prelude/Sequence.swift:83:55: error: 'SubSequence' is not a member type of type 'S'
 81 | }
 82 |
 83 | public func prefix<S: Sequence>(_ n: Int) -> (S) -> S.SubSequence {
    |                                                       `- error: 'SubSequence' is not a member type of type 'S'
 84 |   return { xs in
 85 |     xs.prefix(n)
/Users/admin/builder/spi-builder-workspace/Sources/Prelude/Sequence.swift:89:85: error: 'SubSequence' is not a member type of type 'S'
 87 | }
 88 |
 89 | public func prefix<S: Sequence>(while p: @escaping (S.Element) -> Bool) -> (S) -> S.SubSequence {
    |                                                                                     `- error: 'SubSequence' is not a member type of type 'S'
 90 |   return { xs in
 91 |     xs.prefix(while: p)
/Users/admin/builder/spi-builder-workspace/Sources/Prelude/Sequence.swift:103:55: error: 'SubSequence' is not a member type of type 'S'
101 | }
102 |
103 | public func suffix<S: Sequence>(_ n: Int) -> (S) -> S.SubSequence {
    |                                                       `- error: 'SubSequence' is not a member type of type 'S'
104 |   return { xs in
105 |     xs.suffix(n)
Failed frontend command:
/Applications/Xcode-27.0.0-Release.Candidate.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift-frontend -frontend -emit-module -experimental-skip-non-inlinable-function-bodies-without-types /Users/admin/builder/spi-builder-workspace/Sources/Prelude/Array.swift /Users/admin/builder/spi-builder-workspace/Sources/Prelude/Choice.swift /Users/admin/builder/spi-builder-workspace/Sources/Prelude/Either.swift /Users/admin/builder/spi-builder-workspace/Sources/Prelude/Function.swift /Users/admin/builder/spi-builder-workspace/Sources/Prelude/KeyPath.swift /Users/admin/builder/spi-builder-workspace/Sources/Prelude/Monoid.swift /Users/admin/builder/spi-builder-workspace/Sources/Prelude/Operators.swift /Users/admin/builder/spi-builder-workspace/Sources/Prelude/Optional.swift /Users/admin/builder/spi-builder-workspace/Sources/Prelude/PrecedenceGroups.swift /Users/admin/builder/spi-builder-workspace/Sources/Prelude/Semigroup.swift /Users/admin/builder/spi-builder-workspace/Sources/Prelude/Sequence.swift /Users/admin/builder/spi-builder-workspace/Sources/Prelude/String.swift /Users/admin/builder/spi-builder-workspace/Sources/Prelude/Strong.swift /Users/admin/builder/spi-builder-workspace/Sources/Prelude/Tuple.swift /Users/admin/builder/spi-builder-workspace/Sources/Prelude/Unit.swift -target arm64-apple-macos12.0 -Xllvm -aarch64-use-tbi -enable-objc-interop -stack-check -sdk /Applications/Xcode-27.0.0-Release.Candidate.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX27.0.sdk -I /Users/admin/builder/spi-builder-workspace/.build/out/Products/Debug -Isystem /Applications/Xcode-27.0.0-Release.Candidate.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib -F /Users/admin/builder/spi-builder-workspace/.build/out/Products/Debug -F /Applications/Xcode-27.0.0-Release.Candidate.app/Contents/Developer/Platforms/MacOSX.platform/Developer/Library/Frameworks -module-cache-path /Users/admin/builder/spi-builder-workspace/.build/out/ModuleCache.noindex -color-diagnostics -Xcc -fcolor-diagnostics -enable-testing -g -debug-info-format\=dwarf -dwarf-version\=4 -swift-version 4 -Onone -D SWIFT_PACKAGE -D DEBUG -D SWIFT_MODULE_RESOURCE_BUNDLE_UNAVAILABLE -D Xcode -serialize-debugging-options -enable-experimental-feature DebugDescriptionMacro -empty-abi-descriptor -plugin-path /Applications/Xcode-27.0.0-Release.Candidate.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/host/plugins/testing -validate-clang-modules-once -clang-build-session-file /Users/admin/builder/spi-builder-workspace/.build/out/ModuleCache.noindex/Session.modulevalidation -Xcc -working-directory -Xcc /Users/admin/builder -enable-anonymous-context-mangled-names -file-compilation-dir /Users/admin/builder -Xcc -D_LIBCPP_HARDENING_MODE\=_LIBCPP_HARDENING_MODE_DEBUG -Xcc -ivfsstatcache -Xcc /Users/admin/builder/spi-builder-workspace/.build/out/SDKStatCaches.noindex/macosx27.0-26A425-80c5bbf1d171475443272936d42f90a36a22442a12e9d48fe1a705f55a1adfc4.sdkstatcache -Xcc -fmodules-prune-interval\=86400 -Xcc -fmodules-prune-after\=345600 -Xcc -I/Users/admin/builder/spi-builder-workspace/.build/out/Products/Debug/include -Xcc -I/Users/admin/builder/spi-builder-workspace/.build/out/Intermediates.noindex/Prelude.build/Debug/Prelude-t.build/DerivedSources-normal/arm64 -Xcc -I/Users/admin/builder/spi-builder-workspace/.build/out/Intermediates.noindex/Prelude.build/Debug/Prelude-t.build/DerivedSources/arm64 -Xcc -I/Users/admin/builder/spi-builder-workspace/.build/out/Intermediates.noindex/Prelude.build/Debug/Prelude-t.build/DerivedSources -Xcc -DSWIFT_PACKAGE -Xcc -DDEBUG\=1 -no-auto-bridging-header-chaining -module-name Prelude -const-gather-protocols-file /Users/admin/builder/spi-builder-workspace/.build/out/Intermediates.noindex/Prelude.build/Debug/Prelude-t.build/Objects-normal/arm64/Prelude_const_extract_protocols.json -disable-clang-spi -target-sdk-version 27.0 -target-sdk-name macosx27.0 -external-plugin-path /Applications/Xcode-27.0.0-Release.Candidate.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib/swift/host/plugins\#/Applications/Xcode-27.0.0-Release.Candidate.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/bin/swift-plugin-server -external-plugin-path /Applications/Xcode-27.0.0-Release.Candidate.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/local/lib/swift/host/plugins\#/Applications/Xcode-27.0.0-Release.Candidate.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/bin/swift-plugin-server -in-process-plugin-server-path /Applications/Xcode-27.0.0-Release.Candidate.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/host/libSwiftInProcPluginServer.dylib -plugin-path /Applications/Xcode-27.0.0-Release.Candidate.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/host/plugins -plugin-path /Applications/Xcode-27.0.0-Release.Candidate.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/local/lib/swift/host/plugins -emit-module-doc-path /Users/admin/builder/spi-builder-workspace/.build/out/Intermediates.noindex/Prelude.build/Debug/Prelude-t.build/Objects-normal/arm64/Prelude.swiftdoc -emit-module-source-info-path /Users/admin/builder/spi-builder-workspace/.build/out/Intermediates.noindex/Prelude.build/Debug/Prelude-t.build/Objects-normal/arm64/Prelude.swiftsourceinfo -emit-objc-header-path /Users/admin/builder/spi-builder-workspace/.build/out/Intermediates.noindex/Prelude.build/Debug/Prelude-t.build/Objects-normal/arm64/Prelude-Swift.h -serialize-diagnostics-path /Users/admin/builder/spi-builder-workspace/.build/out/Intermediates.noindex/Prelude.build/Debug/Prelude-t.build/Objects-normal/arm64/Prelude-primary-emit-module.dia -emit-dependencies-path /Users/admin/builder/spi-builder-workspace/.build/out/Intermediates.noindex/Prelude.build/Debug/Prelude-t.build/Objects-normal/arm64/Prelude-primary-emit-module.d -parse-as-library -o /Users/admin/builder/spi-builder-workspace/.build/out/Intermediates.noindex/Prelude.build/Debug/Prelude-t.build/Objects-normal/arm64/Prelude.swiftmodule -emit-abi-descriptor-path /Users/admin/builder/spi-builder-workspace/.build/out/Intermediates.noindex/Prelude.build/Debug/Prelude-t.build/Objects-normal/arm64/Prelude.abi.json
error: Build failed
BUILD FAILURE 6.4 macosSpm