Swift Package IndexBuild Information
Failed to build mcp-swift-sdk, reference main (e76d61), with Swift 6.3 for macOS (SPM) on 16 Apr 2026 18:06:17 UTC.
Build Command
env DEVELOPER_DIR=/Applications/Xcode-26.4.0.app xcrun swift build --arch arm64Build Log
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RunAll
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Builder version: 4.70.0
Interrupt handler set up.
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Checkout
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Clone URL: https://github.com/ShenghaiWang/swift-mcp-sdk.git
Reference: main
Initialized empty Git repository in /Users/admin/builder/spi-builder-workspace/.git/
From https://github.com/ShenghaiWang/swift-mcp-sdk
* branch main -> FETCH_HEAD
* [new branch] main -> origin/main
HEAD is now at e76d611 Bump version to 0.10.0
Cloned https://github.com/ShenghaiWang/swift-mcp-sdk.git
Revision (git rev-parse @):
e76d61155bf00482ea8f2ff78fca08a4eece410e
SUCCESS checkout https://github.com/ShenghaiWang/swift-mcp-sdk.git at main
Fetching https://github.com/apple/swift-system.git
Fetching https://github.com/loopwork-ai/eventsource.git
Fetching https://github.com/apple/swift-log.git
[1/271] Fetching eventsource
[99/6876] Fetching eventsource, swift-log
[471/12477] Fetching eventsource, swift-log, swift-system
Fetched https://github.com/loopwork-ai/eventsource.git from cache (1.22s)
Fetched https://github.com/apple/swift-system.git from cache (1.22s)
Fetched https://github.com/apple/swift-log.git from cache (1.22s)
Fetching https://github.com/mattt/eventsource.git
[1/271] Fetching eventsource
Fetched https://github.com/mattt/eventsource.git from cache (0.76s)
Computing version for https://github.com/mattt/eventsource.git
Computed https://github.com/mattt/eventsource.git at 1.1.0 (2.60s)
Computing version for https://github.com/apple/swift-log.git
Computed https://github.com/apple/swift-log.git at 1.6.2 (0.60s)
Computing version for https://github.com/apple/swift-system.git
Computed https://github.com/apple/swift-system.git at 1.4.0 (0.58s)
Creating working copy for https://github.com/mattt/eventsource.git
Working copy of https://github.com/mattt/eventsource.git resolved at 1.1.0
Creating working copy for https://github.com/apple/swift-log.git
Working copy of https://github.com/apple/swift-log.git resolved at 1.6.2
Creating working copy for https://github.com/apple/swift-system.git
Working copy of https://github.com/apple/swift-system.git resolved at 1.4.0
========================================
ResolveProductDependencies
========================================
Resolving dependencies ...
{
"identity": ".resolve-product-dependencies",
"name": "resolve-dependencies",
"url": "/Users/admin/builder/spi-builder-workspace/.resolve-product-dependencies",
"version": "unspecified",
"path": "/Users/admin/builder/spi-builder-workspace/.resolve-product-dependencies",
"traits": [
"default"
],
"dependencies": [
{
"identity": "swift-mcp-sdk",
"name": "mcp-swift-sdk",
"url": "https://github.com/ShenghaiWang/swift-mcp-sdk.git",
"version": "unspecified",
"path": "/Users/admin/builder/spi-builder-workspace/.resolve-product-dependencies/.build/checkouts/swift-mcp-sdk",
"traits": [
"default"
],
"dependencies": [
{
"identity": "swift-system",
"name": "swift-system",
"url": "https://github.com/apple/swift-system.git",
"version": "1.6.4",
"path": "/Users/admin/builder/spi-builder-workspace/.resolve-product-dependencies/.build/checkouts/swift-system",
"traits": [
"default"
],
"dependencies": [
]
},
{
"identity": "swift-log",
"name": "swift-log",
"url": "https://github.com/apple/swift-log.git",
"version": "1.12.0",
"path": "/Users/admin/builder/spi-builder-workspace/.resolve-product-dependencies/.build/checkouts/swift-log",
"traits": [
],
"dependencies": [
]
},
{
"identity": "eventsource",
"name": "EventSource",
"url": "https://github.com/mattt/eventsource.git",
"version": "1.4.1",
"path": "/Users/admin/builder/spi-builder-workspace/.resolve-product-dependencies/.build/checkouts/eventsource",
"traits": [
],
"dependencies": [
{
"identity": "swift-nio",
"name": "swift-nio",
"url": "https://github.com/apple/swift-nio.git",
"version": "2.98.0",
"path": "/Users/admin/builder/spi-builder-workspace/.resolve-product-dependencies/.build/checkouts/swift-nio",
"traits": [
"default"
],
"dependencies": [
{
"identity": "swift-atomics",
"name": "swift-atomics",
"url": "https://github.com/apple/swift-atomics.git",
"version": "1.3.0",
"path": "/Users/admin/builder/spi-builder-workspace/.resolve-product-dependencies/.build/checkouts/swift-atomics",
"traits": [
"default"
],
"dependencies": [
]
},
{
"identity": "swift-collections",
"name": "swift-collections",
"url": "https://github.com/apple/swift-collections.git",
"version": "1.4.1",
"path": "/Users/admin/builder/spi-builder-workspace/.resolve-product-dependencies/.build/checkouts/swift-collections",
"traits": [
],
"dependencies": [
]
},
{
"identity": "swift-system",
"name": "swift-system",
"url": "https://github.com/apple/swift-system.git",
"version": "1.6.4",
"path": "/Users/admin/builder/spi-builder-workspace/.resolve-product-dependencies/.build/checkouts/swift-system",
"traits": [
"default"
],
"dependencies": [
]
}
]
}
]
}
]
}
]
}
Fetching https://github.com/ShenghaiWang/swift-mcp-sdk.git
[1/787] Fetching swift-mcp-sdk
Fetched https://github.com/ShenghaiWang/swift-mcp-sdk.git from cache (0.94s)
Fetching https://github.com/apple/swift-system.git from cache
Fetching https://github.com/apple/swift-log.git from cache
Fetching https://github.com/mattt/eventsource.git from cache
Fetched https://github.com/apple/swift-system.git from cache (0.56s)
Fetched https://github.com/apple/swift-log.git from cache (0.56s)
Fetched https://github.com/mattt/eventsource.git from cache (0.57s)
Computing version for https://github.com/mattt/eventsource.git
Computed https://github.com/mattt/eventsource.git at 1.4.1 (1.16s)
Fetching https://github.com/apple/swift-nio.git
[1/83162] Fetching swift-nio
Fetched https://github.com/apple/swift-nio.git from cache (6.34s)
Computing version for https://github.com/apple/swift-system.git
Computed https://github.com/apple/swift-system.git at 1.6.4 (6.98s)
Computing version for https://github.com/apple/swift-log.git
Computed https://github.com/apple/swift-log.git at 1.12.0 (0.61s)
Computing version for https://github.com/apple/swift-nio.git
Computed https://github.com/apple/swift-nio.git at 2.98.0 (1.04s)
Fetching https://github.com/apple/swift-collections.git
Fetching https://github.com/apple/swift-atomics.git
[1/1820] Fetching swift-atomics
[602/25371] Fetching swift-atomics, swift-collections
Fetched https://github.com/apple/swift-atomics.git from cache (2.10s)
Fetched https://github.com/apple/swift-collections.git from cache (2.10s)
Computing version for https://github.com/apple/swift-atomics.git
Computed https://github.com/apple/swift-atomics.git at 1.3.0 (2.88s)
Computing version for https://github.com/apple/swift-collections.git
Computed https://github.com/apple/swift-collections.git at 1.4.1 (0.70s)
Creating working copy for https://github.com/mattt/eventsource.git
Working copy of https://github.com/mattt/eventsource.git resolved at 1.4.1
Creating working copy for https://github.com/apple/swift-system.git
Working copy of https://github.com/apple/swift-system.git resolved at 1.6.4
Creating working copy for https://github.com/apple/swift-log.git
Working copy of https://github.com/apple/swift-log.git resolved at 1.12.0
Creating working copy for https://github.com/apple/swift-collections.git
Working copy of https://github.com/apple/swift-collections.git resolved at 1.4.1
Creating working copy for https://github.com/ShenghaiWang/swift-mcp-sdk.git
Working copy of https://github.com/ShenghaiWang/swift-mcp-sdk.git resolved at main (e76d611)
Creating working copy for https://github.com/apple/swift-atomics.git
Working copy of https://github.com/apple/swift-atomics.git resolved at 1.3.0
Creating working copy for https://github.com/apple/swift-nio.git
Working copy of https://github.com/apple/swift-nio.git resolved at 2.98.0
warning: '.resolve-product-dependencies': dependency 'swift-mcp-sdk' is not used by any target
Found 3 product dependencies
- swift-system
- swift-log
- EventSource
========================================
Build
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Selected platform: macosSpm
Swift version: 6.3
Building package at path: $PWD
https://github.com/ShenghaiWang/swift-mcp-sdk.git
Running build ...
env DEVELOPER_DIR=/Applications/Xcode-26.4.0.app xcrun swift build --arch arm64
Building for debugging...
[0/6] Write sources
[4/6] Compiling CSystem shims.c
[5/6] Write swift-version--6988338F2F200930.txt
[7/43] Compiling SystemPackage FilePathComponentView.swift
[8/43] Compiling SystemPackage FilePathComponents.swift
[9/43] Compiling SystemPackage FilePathParsing.swift
[10/46] Emitting module SystemPackage
[11/46] Compiling SystemPackage FilePathString.swift
[12/46] Compiling SystemPackage FilePathSyntax.swift
[13/46] Compiling SystemPackage FilePathTemp.swift
[14/46] Compiling SystemPackage FileHelpers.swift
[15/46] Compiling SystemPackage FileOperations.swift
[16/46] Compiling SystemPackage FilePath.swift
[17/46] Compiling SystemPackage Errno.swift
[18/46] Compiling SystemPackage ErrnoWindows.swift
[19/46] Compiling SystemPackage FileDescriptor.swift
[20/46] Compiling SystemPackage Util+StringArray.swift
[21/46] Compiling SystemPackage Util.swift
[22/46] Compiling SystemPackage UtilConsumers.swift
[23/46] Compiling SystemPackage FilePathTempPosix.swift
[24/46] Compiling SystemPackage FilePathTempWindows.swift
[25/46] Compiling SystemPackage FilePathWindows.swift
[26/46] Compiling SystemPackage Constants.swift
[27/46] Compiling SystemPackage Exports.swift
[28/46] Compiling SystemPackage Mocking.swift
[29/46] Compiling SystemPackage RawBuffer.swift
[30/46] Compiling SystemPackage Syscalls.swift
[31/46] Compiling SystemPackage WindowsSyscallAdapters.swift
[32/46] Compiling SystemPackage FilePermissions.swift
[33/46] Compiling SystemPackage Backcompat.swift
[34/46] Compiling SystemPackage CInterop.swift
[35/46] Compiling SystemPackage MachPort.swift
[36/46] Compiling SystemPackage PlatformString.swift
[37/46] Compiling SystemPackage SystemString.swift
[38/46] Compiling Logging Logging.swift
[39/46] Compiling Logging Locks.swift
[40/46] Compiling Logging MetadataProvider.swift
[41/46] Compiling Logging LogHandler.swift
[42/46] Emitting module Logging
[43/46] Compiling EventSource EventSource.swift
[44/46] Compiling EventSource AsyncSequence+Events.swift
[45/46] Compiling EventSource AsyncEventsSequence.swift
[46/46] Emitting module EventSource
[47/65] Compiling MCP Prompts.swift
[48/65] Compiling MCP Resources.swift
[49/67] Compiling MCP Ping.swift
[50/67] Compiling MCP Value.swift
[51/67] Compiling MCP Versioning.swift
[52/67] Compiling MCP Client.swift
[53/67] Compiling MCP StdioTransport.swift
[54/67] Compiling MCP UnitInterval.swift
[55/67] Compiling MCP Lifecycle.swift
[56/67] Compiling MCP Messages.swift
[57/67] Compiling MCP Transport.swift
[58/67] Compiling MCP HTTPClientTransport.swift
[59/67] Compiling MCP Error.swift
[60/67] Compiling MCP ID.swift
[61/67] Emitting module MCP
[62/67] Compiling MCP Sampling.swift
[63/67] Compiling MCP Data+Extensions.swift
[64/67] Compiling MCP InMemoryTransport.swift
/Users/admin/builder/spi-builder-workspace/Sources/MCP/Base/Transports/NetworkTransport.swift:581:33: error: sending 'sendContinuationResumed' risks causing data races [#SendingRisksDataRace]
579 |
580 | Task { @MainActor in
581 | if !sendContinuationResumed {
| |- error: sending 'sendContinuationResumed' risks causing data races [#SendingRisksDataRace]
| `- note: task-isolated 'sendContinuationResumed' is captured by a main actor-isolated closure. main actor-isolated uses in closure may race against later nonisolated uses
582 | sendContinuationResumed = true
583 | if let error = error {
/Users/admin/builder/spi-builder-workspace/Sources/MCP/Base/Transports/NetworkTransport.swift:812:29: error: sending 'receiveContinuationResumed' risks causing data races [#SendingRisksDataRace]
810 | content, _, isComplete, error in
811 | Task { @MainActor in
812 | if !receiveContinuationResumed {
| |- error: sending 'receiveContinuationResumed' risks causing data races [#SendingRisksDataRace]
| `- note: task-isolated 'receiveContinuationResumed' is captured by a main actor-isolated closure. main actor-isolated uses in closure may race against later nonisolated uses
813 | receiveContinuationResumed = true
814 | if let error = error {
[#SendingRisksDataRace]: <https://docs.swift.org/compiler/documentation/diagnostics/sending-risks-data-race>
[65/67] Compiling MCP NetworkTransport.swift
/Users/admin/builder/spi-builder-workspace/Sources/MCP/Base/Transports/NetworkTransport.swift:581:33: error: sending 'sendContinuationResumed' risks causing data races [#SendingRisksDataRace]
579 |
580 | Task { @MainActor in
581 | if !sendContinuationResumed {
| |- error: sending 'sendContinuationResumed' risks causing data races [#SendingRisksDataRace]
| `- note: task-isolated 'sendContinuationResumed' is captured by a main actor-isolated closure. main actor-isolated uses in closure may race against later nonisolated uses
582 | sendContinuationResumed = true
583 | if let error = error {
/Users/admin/builder/spi-builder-workspace/Sources/MCP/Base/Transports/NetworkTransport.swift:812:29: error: sending 'receiveContinuationResumed' risks causing data races [#SendingRisksDataRace]
810 | content, _, isComplete, error in
811 | Task { @MainActor in
812 | if !receiveContinuationResumed {
| |- error: sending 'receiveContinuationResumed' risks causing data races [#SendingRisksDataRace]
| `- note: task-isolated 'receiveContinuationResumed' is captured by a main actor-isolated closure. main actor-isolated uses in closure may race against later nonisolated uses
813 | receiveContinuationResumed = true
814 | if let error = error {
[#SendingRisksDataRace]: <https://docs.swift.org/compiler/documentation/diagnostics/sending-risks-data-race>
[66/67] Compiling MCP Server.swift
/Users/admin/builder/spi-builder-workspace/Sources/MCP/Server/Server.swift:267:44: warning: capture of non-Sendable type 'M.Type' in an isolated closure [#SendableMetatypes]
265 | ) -> Self {
266 | methodHandlers[M.name] = TypedRequestHandler { (request: Request<M>) -> Response<M> in
267 | let result = try await handler(request.params)
| `- warning: capture of non-Sendable type 'M.Type' in an isolated closure [#SendableMetatypes]
268 | return Response(id: request.id, result: result)
269 | }
[#SendableMetatypes]: <https://docs.swift.org/compiler/documentation/diagnostics/sendable-metatypes>
[67/67] Compiling MCP Tools.swift
/Users/admin/builder/spi-builder-workspace/Sources/MCP/Server/Server.swift:267:44: warning: capture of non-Sendable type 'M.Type' in an isolated closure [#SendableMetatypes]
265 | ) -> Self {
266 | methodHandlers[M.name] = TypedRequestHandler { (request: Request<M>) -> Response<M> in
267 | let result = try await handler(request.params)
| `- warning: capture of non-Sendable type 'M.Type' in an isolated closure [#SendableMetatypes]
268 | return Response(id: request.id, result: result)
269 | }
[#SendableMetatypes]: <https://docs.swift.org/compiler/documentation/diagnostics/sendable-metatypes>
BUILD FAILURE 6.3 macosSpm