MCPKit – Build Information – Swift Package Index

Build Information

Failed to build MCPKit, reference 0.6.0 (c038b0), with Swift 6.4 for Linux on 28 Sep 2026 03:23:15 UTC.

Build Command

bash -c docker run --pull=always --rm -v "checkouts-54344845-3":/host -w "$PWD" -e JAVA_HOME="/root/.sdkman/candidates/java/current" -e SPI_BUILD="1" -e SPI_PROCESSING="1" registry.gitlab.com/saguaro1/spi-images:basic-6.4-latest swift build --triple x86_64-unknown-linux-gnu 2>&1

Build Log

========================================
RunAll
========================================
Builder version: 5.1.0
Interrupt handler set up.
========================================
Checkout
========================================
Clone URL: https://github.com/adamtheturtle/MCPKit.git
Reference: 0.6.0
Initialized empty Git repository in /host/spi-builder-workspace/.git/
hint: Using 'master' as the name for the initial branch. This default branch name
hint: is subject to change. To configure the initial branch name to use in all
hint: of your new repositories, which will suppress this warning, call:
hint:
hint: 	git config --global init.defaultBranch <name>
hint:
hint: Names commonly chosen instead of 'master' are 'main', 'trunk' and
hint: 'development'. The just-created branch can be renamed via this command:
hint:
hint: 	git branch -m <name>
From https://github.com/adamtheturtle/MCPKit
 * tag               0.6.0      -> FETCH_HEAD
HEAD is now at c038b06 Prepare 0.6.0 release (#110)
Cloned https://github.com/adamtheturtle/MCPKit.git
Revision (git rev-parse @):
c038b066c9dbf9132e4433984e02b4912291f5c1
SPI manifest file found: $PWD/.spi.yml
SUCCESS checkout https://github.com/adamtheturtle/MCPKit.git at 0.6.0
========================================
Build
========================================
Selected platform:         linux
Swift version:             6.4
Building package at path:  $PWD
https://github.com/adamtheturtle/MCPKit.git
Running build ...
bash -c docker run --pull=always --rm -v "checkouts-54344845-3":/host -w "$PWD" -e JAVA_HOME="/root/.sdkman/candidates/java/current" -e SPI_BUILD="1" -e SPI_PROCESSING="1" registry.gitlab.com/saguaro1/spi-images:basic-6.4-latest swift build --triple x86_64-unknown-linux-gnu 2>&1
basic-6.4-latest: Pulling from saguaro1/spi-images
Digest: sha256:c77fcce225e223ac0fafed844619173fc6de8d62dd560eeb28db3182af6a282b
Status: Image is up to date for registry.gitlab.com/saguaro1/spi-images:basic-6.4-latest
Fetching https://github.com/modelcontextprotocol/swift-sdk.git
[1/3942] Fetching swift-sdk
Fetching https://github.com/swiftlang/swift-docc-plugin
[3943/6287] Fetching swift-sdk, swift-docc-plugin
Fetched https://github.com/modelcontextprotocol/swift-sdk.git (1.55s)
Fetched https://github.com/swiftlang/swift-docc-plugin (0.68s)
Computing version for https://github.com/modelcontextprotocol/swift-sdk.git
Computed https://github.com/modelcontextprotocol/swift-sdk.git at 0.12.1 (1.90s)
Fetching https://github.com/apple/swift-nio.git
[1/86192] Fetching swift-nio
Fetching https://github.com/apple/swift-system.git
Fetching https://github.com/apple/swift-log.git
Fetching https://github.com/mattt/eventsource.git
Fetched https://github.com/apple/swift-nio.git (4.80s)
[1/8165] Fetching swift-log
[3512/8468] Fetching swift-log, eventsource
Fetched https://github.com/mattt/eventsource.git (0.59s)
[7512/8165] Fetching swift-log
[8166/15151] Fetching swift-log, swift-system
Fetched https://github.com/apple/swift-log.git (0.83s)
Fetched https://github.com/apple/swift-system.git (0.83s)
Computing version for https://github.com/swiftlang/swift-docc-plugin
Computed https://github.com/swiftlang/swift-docc-plugin at 1.5.0 (7.33s)
Fetching https://github.com/swiftlang/swift-docc-symbolkit
[1/3831] Fetching swift-docc-symbolkit
Fetched https://github.com/swiftlang/swift-docc-symbolkit (0.69s)
Computing version for https://github.com/swiftlang/swift-docc-symbolkit
Computed https://github.com/swiftlang/swift-docc-symbolkit at 1.0.0 (1.17s)
Computing version for https://github.com/mattt/eventsource.git
Computed https://github.com/mattt/eventsource.git at 1.5.1 (0.30s)
Computing version for https://github.com/apple/swift-log.git
Computed https://github.com/apple/swift-log.git at 1.15.1 (0.39s)
Computing version for https://github.com/apple/swift-system.git
Computed https://github.com/apple/swift-system.git at 1.8.1 (0.38s)
Computing version for https://github.com/apple/swift-nio.git
Computed https://github.com/apple/swift-nio.git at 2.103.0 (0.54s)
Fetching https://github.com/apple/swift-atomics.git
Fetching https://github.com/apple/swift-collections.git
[1/1885] Fetching swift-atomics
Fetched https://github.com/apple/swift-atomics.git (0.72s)
[1/27779] Fetching swift-collections
Fetched https://github.com/apple/swift-collections.git (1.57s)
Computing version for https://github.com/apple/swift-atomics.git
Computed https://github.com/apple/swift-atomics.git at 1.3.1 (1.88s)
Computing version for https://github.com/apple/swift-collections.git
Computed https://github.com/apple/swift-collections.git at 1.7.1 (0.54s)
Creating working copy for https://github.com/mattt/eventsource.git
Working copy of https://github.com/mattt/eventsource.git resolved at 1.5.1
Creating working copy for https://github.com/modelcontextprotocol/swift-sdk.git
Working copy of https://github.com/modelcontextprotocol/swift-sdk.git resolved at 0.12.1
Creating working copy for https://github.com/apple/swift-collections.git
Working copy of https://github.com/apple/swift-collections.git resolved at 1.7.1
Creating working copy for https://github.com/apple/swift-nio.git
Working copy of https://github.com/apple/swift-nio.git resolved at 2.103.0
Creating working copy for https://github.com/apple/swift-system.git
Working copy of https://github.com/apple/swift-system.git resolved at 1.8.1
Creating working copy for https://github.com/apple/swift-atomics.git
Working copy of https://github.com/apple/swift-atomics.git resolved at 1.3.1
Creating working copy for https://github.com/swiftlang/swift-docc-plugin
Working copy of https://github.com/swiftlang/swift-docc-plugin resolved at 1.5.0
Creating working copy for https://github.com/swiftlang/swift-docc-symbolkit
Working copy of https://github.com/swiftlang/swift-docc-symbolkit resolved at 1.0.0
Creating working copy for https://github.com/apple/swift-log.git
Working copy of https://github.com/apple/swift-log.git resolved at 1.15.1
Building for debugging...
[Computing dependencies]
[Constructing description]
[Pre-planning 1 / 273]
[Planning deferred tasks]
[21 / 93] MCPKitStdioFailureFixture-product
[60 / 104] Logging
[62 / 113] CSystem
[64 / 113] SystemPackage
[74 / 113] SystemPackage
[78 / 113] SystemPackage
[79 / 113] SystemPackage
[81 / 113] Logging-product
[82 / 113] Logging-product
[83 / 114] MCP
[85 / 123] MCP
[87 / 124] MCP
[88 / 124] MCP
[89 / 124] MCP
[90 / 124] MCP
[91 / 124] MCP
[92 / 125] SystemPackage
[93 / 125] MCP
[100 / 125] MCP
[105 / 135] Logging
[107 / 135] SystemPackage
[109 / 135] MCPKit
/host/spi-builder-workspace/Sources/MCPKit/StdioBootstrap.swift:30:5: [1;33mwarning: [1;39m'public' modifier is redundant for static property declared in a public extension[0;0m
 [0;36m28 |[0;0m     /// ``runOverStdioUntilExit(name:version:capabilities:isEnabled:disabledMessage:onLaunch:provider:)``:
 [0;36m29 |[0;0m     /// tools only, without prompt or resource advertisements.
 [0;36m30 |[0;0m     public static let stdioDefaultCapabilities = Server.Capabilities(
    [0;36m|[0;0m     `- [1;33mwarning: [1;39m'public' modifier is redundant for static property declared in a public extension[0;0m
 [0;36m31 |[0;0m         tools: .init(listChanged: false)
 [0;36m32 |[0;0m     )
[111 / 135] MCPKit
[113 / 135] MCPKit
[118 / 135] MCPKit
[119 / 137] MCPKitStdioFailureFixture-product
[121 / 138] MCPKitStdioFailureFixture-product
[123 / 139]
[127 / 144] JSONLLogAppendFixture-product
[129 / 145] MCPKitStdioFailureFixture-product
/host/spi-builder-workspace/Sources/MCPKit/StdioBootstrap.swift:30:5: [1;33mwarning: [1;39m'public' modifier is redundant for static property declared in a public extension[0;0m
 [0;36m28 |[0;0m     /// ``runOverStdioUntilExit(name:version:capabilities:isEnabled:disabledMessage:onLaunch:provider:)``:
 [0;36m29 |[0;0m     /// tools only, without prompt or resource advertisements.
 [0;36m30 |[0;0m     public static let stdioDefaultCapabilities = Server.Capabilities(
    [0;36m|[0;0m     `- [1;33mwarning: [1;39m'public' modifier is redundant for static property declared in a public extension[0;0m
 [0;36m31 |[0;0m         tools: .init(listChanged: false)
 [0;36m32 |[0;0m     )
[133 / 146] MCPKitExample-product
error: SwiftCompile normal x86_64 failed with a nonzero exit code. Command line:     cd /host

/host/spi-builder-workspace/Tests/JSONLLogAppendFixture/main.swift:21:85: [1;31merror: [1;39mreference to var 'stderr' is not concurrency-safe because it involves shared mutable state[0;0m
[0;36m19 |[0;0m       let count = Int(CommandLine.arguments[4])
[0;36m20 |[0;0m else {
[0;36m21 |[0;0m     fputs("usage: JSONLLogAppendFixture <directory> <fileName> <writer> <count>\n", stderr)
   [0;36m|[0;0m                                                                                     `- [1;31merror: [1;39mreference to var 'stderr' is not concurrency-safe because it involves shared mutable state[0;0m
[0;36m22 |[0;0m     exit(EXIT_FAILURE)
[0;36m23 |[0;0m }
/usr/include/stdio.h:145:14: [1;39mnote: [1;39mvar declared here[0;0m
[0;36m143 |[0;0m extern FILE *stdin;		/* Standard input stream.  */
[0;36m144 |[0;0m extern FILE *stdout;		/* Standard output stream.  */
[0;36m145 |[0;0m extern FILE *stderr;		/* Standard error output stream.  */
    [0;36m|[0;0m              `- [1;39mnote: [1;39mvar declared here[0;0m
[0;36m146 |[0;0m /* C89/C99 say they're macros.  Make them happy.  */
[0;36m147 |[0;0m #define stdin stdin
Failed frontend command:
/usr/bin/swift-frontend -frontend -emit-module -experimental-skip-non-inlinable-function-bodies-without-types /host/spi-builder-workspace/Tests/JSONLLogAppendFixture/main.swift -target x86_64-unknown-linux-gnu -disable-objc-interop -I /host/spi-builder-workspace/.build/out/Products/Debug-linux-x86_64 -module-cache-path /host/spi-builder-workspace/.build/out/ModuleCache.noindex -color-diagnostics -Xcc -fcolor-diagnostics -enable-testing -g -debug-info-format\=dwarf -dwarf-version\=4 -swift-version 6 -Onone -D SWIFT_PACKAGE -D DEBUG -D Xcode -serialize-debugging-options -enable-experimental-feature DebugDescriptionMacro -empty-abi-descriptor -external-plugin-path /usr/lib/swift/host/plugins/testing\#/usr/bin/swift-plugin-server -validate-clang-modules-once -clang-build-session-file /host/spi-builder-workspace/.build/out/ModuleCache.noindex/Session.modulevalidation -Xcc -working-directory -Xcc /host -enable-anonymous-context-mangled-names -file-compilation-dir /host -Xcc -fmodule-map-file\=/host/spi-builder-workspace/.build/checkouts/swift-system/Sources/CSystem/include/module.modulemap -Xcc -fno-omit-frame-pointer -Xcc -D_LIBCPP_HARDENING_MODE\=_LIBCPP_HARDENING_MODE_DEBUG -Xcc -fmodules-prune-interval\=86400 -Xcc -fmodules-prune-after\=345600 -Xcc -I/host/spi-builder-workspace/.build/checkouts/swift-system/Sources/CSystem/include -Xcc -I/host/spi-builder-workspace/.build/out/Products/Debug-linux-x86_64/include -Xcc -I/host/spi-builder-workspace/.build/out/Intermediates.noindex/MCPKit.build/Debug-linux-x86_64/JSONLLogAppendFixture-p.build/DerivedSources-normal/x86_64 -Xcc -I/host/spi-builder-workspace/.build/out/Intermediates.noindex/MCPKit.build/Debug-linux-x86_64/JSONLLogAppendFixture-p.build/DerivedSources/x86_64 -Xcc -I/host/spi-builder-workspace/.build/out/Intermediates.noindex/MCPKit.build/Debug-linux-x86_64/JSONLLogAppendFixture-p.build/DerivedSources -Xcc -DSWIFT_PACKAGE -Xcc -DDEBUG\=1 -no-auto-bridging-header-chaining -module-name JSONLLogAppendFixture -package-name spi_builder_workspace -const-gather-protocols-file /host/spi-builder-workspace/.build/out/Intermediates.noindex/MCPKit.build/Debug-linux-x86_64/JSONLLogAppendFixture-p.build/Objects-normal/x86_64/JSONLLogAppendFixture_const_extract_protocols.json -in-process-plugin-server-path /usr/lib/swift/host/libSwiftInProcPluginServer.so -plugin-path /usr/lib/swift/host/plugins -plugin-path /usr/local/lib/swift/host/plugins -emit-module-doc-path /host/spi-builder-workspace/.build/out/Intermediates.noindex/MCPKit.build/Debug-linux-x86_64/JSONLLogAppendFixture-p.build/Objects-normal/x86_64/Modules/JSONLLogAppendFixture.swiftdoc -emit-module-source-info-path /host/spi-builder-workspace/.build/out/Intermediates.noindex/MCPKit.build/Debug-linux-x86_64/JSONLLogAppendFixture-p.build/Objects-normal/x86_64/Modules/JSONLLogAppendFixture.swiftsourceinfo -serialize-diagnostics-path /host/spi-builder-workspace/.build/out/Intermediates.noindex/MCPKit.build/Debug-linux-x86_64/JSONLLogAppendFixture-p.build/Objects-normal/x86_64/JSONLLogAppendFixture-primary-emit-module.dia -emit-dependencies-path /host/spi-builder-workspace/.build/out/Intermediates.noindex/MCPKit.build/Debug-linux-x86_64/JSONLLogAppendFixture-p.build/Objects-normal/x86_64/JSONLLogAppendFixture-primary-emit-module.d -o /host/spi-builder-workspace/.build/out/Intermediates.noindex/MCPKit.build/Debug-linux-x86_64/JSONLLogAppendFixture-p.build/Objects-normal/x86_64/Modules/JSONLLogAppendFixture.swiftmodule
error: Build failed
BUILD FAILURE 6.4 linux