Build issue on nightly-6.0-amazonlinux2

[AndrewBarba]

I'm currently experiencing build issues on nightly-6.0-amazonlinux2. Appears related to the new Foundation on nightly:

/workspace/.build/checkouts/swift-http-types/Sources/HTTPTypesFoundation/HTTPRequest+URL.swift:15:8: error: no such module 'CoreFoundation'
 13 | //===----------------------------------------------------------------------===//
 14 | 
 15 | import CoreFoundation
    |        `- error: no such module 'CoreFoundation'
 16 | import Foundation
 17 | import HTTPTypes

Edit: Full command used to build

/usr/local/bin/docker run \
  --platform linux/arm64 \
  --rm \
  -v ./:/workspace \
  -w /workspace \
  swiftlang/swift:nightly-6.0-amazonlinux2 bash -cl swift build -c release -Xswiftc -Osize --static-swift-stdlib

[guoye-zhang]

@jrflat Do you know what’s happening there?

[Lukasa]

I believe CoreFoundation is not intended to be part of the x-platform piece of Foundation, and so we probably shouldn't depend on it. This is probably related to re-homing Foundation on swift-foundation.

[FranzBusch]

I agree. We must never import CoreFoundation on non-Darwin platforms. We don't guarantee any stability around that and with the re-core CoreFoundation is going away long term on non-Darwin platforms

[jrflat]

Yeah, we'll probably need to migrate from the CFURL functions to using URL, at least on non-Darwin platforms. I can help with this

cc: @jmschonfeld

[guoye-zhang]

This CoreFoundation dependency is unfortunately unavoidable today unless Foundation URL starts supporting WHATWG parsing.

[jmschonfeld]

Yes CoreFoundation is not public API on non-Darwin and should not be relied upon outside of swift-corelibs-foundation so it should be removed from here. That being said, I don't think we explicitly removed the CoreFoundation module in the re-core and we still have projects that import it (incorrectly) that are successfully building. I can also successfully import the module from swift repl inside of a nightly-amazonlinux2 container. Let me check nightly-6.0-amazonlinux2

[jmschonfeld]

While I do not advocate for any CF code, the following does still appear to be functional to me on the latest nightly-6.0-amazonlinux2 container:

root@nightly-6 Repos]# swift test.swift
16
[root@nightly-6 Repos]# cat test.swift
import CoreFoundation
import Foundation

var url = URL(string: "http://apple.com")! as NSURL
let cf = unsafeBitCast(url, to: CFURL.self)
let length = CFURLGetBytes(cf, nil, 0)
print(length)[root@nightly-6 Repos]# swift test.swift
16
[root@nightly-6 Repos]# cat /etc/os-release 
NAME="Amazon Linux"
VERSION="2"
ID="amzn"
ID_LIKE="centos rhel fedora"
VERSION_ID="2"
PRETTY_NAME="Amazon Linux 2"
ANSI_COLOR="0;33"
CPE_NAME="cpe:2.3:o:amazon:amazon_linux:2"
HOME_URL="https://amazonlinux.com/"
SUPPORT_END="2025-06-30"

[AndrewBarba]

@jmschonfeld If helpful, here is full command I'm running to build:

/usr/local/bin/docker run \
  --platform linux/arm64 \
  --rm \
  -v ./:/workspace \
  -w /workspace \
  swiftlang/swift:nightly-6.0-amazonlinux2 bash -cl swift build -c release -Xswiftc -Osize --static-swift-stdlib

[jmschonfeld]

Aha, that --static-swift-stdlib is the key:

[root@nightly-amazonlinux2 Repos]# swiftc -static-stdlib test.swift                                                                                                                                                                                                                                                                                                        
/Repos/test.swift:1:8: error: no such module 'CoreFoundation'
1 | import CoreFoundation
  |        `- error: no such module 'CoreFoundation'
2 | import Foundation
3 | 
[root@nightly-amazonlinux2 Repos]# swiftc test.swift
<no output>

Looks like the CoreFoundation module was removed from the static swift build

[jmschonfeld]

We should consider removing the CoreFoundation usages here at some point, but I've posted swiftlang/swift-corelibs-foundation#5037 to resolve the regression here from previous behavior caused by the re-core (since I expect that this issue might have other unintended consequences so we should likely fix it anyways)