Xcode 26.4: xcodebuild test crashes on iOS 15.2 Simulators before XCTest bootstrap due to ResultDataPublisher missing Foundation.URLRequest.httpMethod symbol

I’m seeing a crash when running XCTest on iOS 15.2 Simulators with Xcode 26.4. The test bundle never starts. xctest crashes before establishing the XCTest connection.

This appears to be a regression from Xcode 26.2. The same test flow worked with Xcode 26.2, but crashes with Xcode 26.4.

This does not appear to be caused by my app or package code. I can reproduce it with a minimal Swift Package that only imports Foundation and has one XCTest case using URLRequest.httpMethod.

Environment:

• Xcode with failure: 26.4
• Xcode that worked: 26.2
• macOS: 26.2
• Destinations tested:
  • iPhone SE (2nd generation), iOS 15.2 Simulator
  • iPad mini (6th generation), iOS 15.2 Simulator
• Test command: xcodebuild test
• Swift Package deployment target: iOS 15.2
• Swift tools version: 6.1

Minimal reproduction package:

Package.swift

// swift-tools-version:6.1

  import PackageDescription

  let package = Package(
      name: "FoundationOnlyRepro",
      platforms: [.iOS("15.2")],
      products: [
          .library(
              name: "FoundationOnlyRepro",
              targets: ["FoundationOnlyRepro"]
          )
      ],
      targets: [
          .target(name: "FoundationOnlyRepro"),
          .testTarget(
              name: "FoundationOnlyReproTests",
              dependencies: ["FoundationOnlyRepro"]
          )
      ],
      swiftLanguageModes: [.v6]
  )

Sources/FoundationOnlyRepro/FoundationOnlyRepro.swift

  import Foundation

  public struct FoundationOnlyRepro {
      public init() {}

      public func makeRequest() -> URLRequest {
          var request = URLRequest(url: URL(string: "https://example.invalid")!)
          request.httpMethod = "GET"
          return request
      }
  }

Tests/FoundationOnlyReproTests/FoundationOnlyReproTests.swift

  import XCTest
  import Foundation
  @testable import FoundationOnlyRepro

  final class FoundationOnlyReproTests: XCTestCase {
      func testURLRequestHTTPMethod() {
          let request = FoundationOnlyRepro().makeRequest()
          XCTAssertEqual(request.httpMethod, "GET")
      }
  }

Command used:

  xcodebuild test \
    -scheme FoundationOnlyRepro \
    -destination 'platform=iOS Simulator,name=iPhone SE (2nd generation),OS=15.2' \
    -derivedDataPath /tmp/rdp-dd \
    -quiet

The same kind of crash also occurs when using an iPad mini (6th generation) iOS 15.2 Simulator destination.

Result:

  Testing failed:
      xctest (...) encountered an error (Early unexpected exit, operation never finished bootstrapping - no restart will be attempted. (Underlying Error: Test crashed with
  signal abrt before establishing connection.))

  ** TEST FAILED **

The diagnostic stderr shows:

  dyld[28688]: Symbol not found: _$s10Foundation10URLRequestV10httpMethodSSSgvs
    Referenced from: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/Library/PrivateFrameworks/ResultDataPublisher.framework/
  ResultDataPublisher
    Expected in: /Library/Developer/CoreSimulator/Profiles/Runtimes/iOS
  15.2.simruntime/Contents/Resources/RuntimeRoot/System/Library/Frameworks/Foundation.framework/Foundation

Demangling the missing symbol:

  xcrun swift-demangle '_$s10Foundation10URLRequestV10httpMethodSSSgvs'

Output:

  Foundation.URLRequest.httpMethod.setter : Swift.String?

I also checked the iOS 15.2 simulator runtime. The symbol appears to exist in:

/Library/Developer/CoreSimulator/Profiles/Runtimes/iOS 15.2.simruntime/Contents/Resources/RuntimeRoot/usr/lib/swift/libswiftFoundation.dylib

but ResultDataPublisher.framework appears to be resolving it from: .../System/Library/Frameworks/Foundation.framework/Foundation

This suggests the crash is in Xcode’s XCTest/result publishing infrastructure, not in the app/test bundle.

Questions:

1. Is Xcode 26.4 + iOS 15.2 Simulator + xcodebuild test expected to be supported?
2. Is there a supported workaround to disable or avoid ResultDataPublisher.framework for command-line XCTest runs?