Support building Swift 5.9 SDKs for Debian Bookworm using Ubuntu Jammy toolchain

Author: xtremekforever

Sources/SwiftSDKGenerator/PlatformModels/LinuxDistribution.swift

@@ -125,7 +125,7 @@ public enum LinuxDistribution: Hashable, Sendable {
           "libc6-dev",
           "libgcc-s1",
           "libgcc-10-dev",
-          "libicu66",
+          "libicu67",
           "libicu-dev",
           "libstdc++-10-dev",
           "libstdc++6",

Sources/SwiftSDKGenerator/PlatformModels/VersionsConfiguration.swift

@@ -26,63 +26,63 @@ public struct VersionsConfiguration: Sendable {
     self.swiftVersion = swiftVersion
     self.swiftBranch = swiftBranch ?? "swift-\(swiftVersion.lowercased())"
     self.lldVersion = lldVersion
-    if case let .debian(debian) = linuxDistribution, debian.version == "11" {
-      logger.warning(
-        "Debian 11 selected but not officially supported by Swift, falling back on Ubuntu 20.04 toolchain..."
-      )
-      self.linuxDistribution = try .init(name: .ubuntu, version: "20.04")
-    } else {
-      self.linuxDistribution = linuxDistribution
-    }
+    self.linuxDistribution = linuxDistribution
     self.linuxArchSuffix =
       targetTriple.arch == .aarch64 ? "-\(Triple.Arch.aarch64.linuxConventionName)" : ""
+    self.logger = logger
   }
 
   let swiftVersion: String
   let swiftBranch: String
   let lldVersion: String
   let linuxDistribution: LinuxDistribution
   let linuxArchSuffix: String
+  private let logger: Logger
 
   var swiftPlatform: String {
     switch self.linuxDistribution {
     case let .ubuntu(ubuntu):
       return "ubuntu\(ubuntu.version)\(self.linuxArchSuffix)"
     case let .debian(debian):
+      if debian.version == "11" {
+        logger.warning(
+          "Debian 11 selected but not officially supported by Swift, falling back on Ubuntu 20.04 toolchain..."
+        )
+        // Ubuntu 20.04 toolchain is binary compatible with Debian 11
+        return "ubuntu20.04\(self.linuxArchSuffix)"
+      } else if self.swiftVersion.hasPrefix("5.9") || self.swiftVersion == "5.10" {
+        logger.warning(
+          "Debian 12 selected but not officially supported by Swift version, falling back on Ubuntu 22.04 toolchain...",
+          metadata: ["swiftVersion": .string(self.swiftVersion)]
+        )
+        // Ubuntu 22.04 toolchain is binary compatible with Debian 12
+        return "ubuntu22.04\(self.linuxArchSuffix)"
+      }
       return "debian\(debian.version)\(self.linuxArchSuffix)"
     case let .rhel(rhel):
       return "\(rhel.rawValue)\(self.linuxArchSuffix)"
     }
   }
 
   func swiftDistributionName(platform: String? = nil) -> String {
-    "swift-\(self.swiftVersion)-\(platform ?? self.swiftPlatform)"
+    return "swift-\(self.swiftVersion)-\(platform ?? self.swiftPlatform)"
   }
 
   func swiftDownloadURL(
     subdirectory: String? = nil,
     platform: String? = nil,
     fileExtension: String = "tar.gz"
   ) -> URL {
-    let computedSubdirectory: String
-    switch self.linuxDistribution {
-    case let .ubuntu(ubuntu):
-      computedSubdirectory =
-        "ubuntu\(ubuntu.version.replacingOccurrences(of: ".", with: ""))\(self.linuxArchSuffix)"
-    case let .debian(debian):
-      computedSubdirectory =
-        "debian\(debian.version.replacingOccurrences(of: ".", with: ""))\(self.linuxArchSuffix)"
-    case let .rhel(rhel):
-      computedSubdirectory = rhel.rawValue
-    }
+    let computedPlatform = platform ?? self.swiftPlatform
+    let computedSubdirectory =
+      subdirectory ?? computedPlatform.replacingOccurrences(of: ".", with: "")
 
     return URL(
       string: """
         https://download.swift.org/\(
           self.swiftBranch
-        )/\(
-          subdirectory ?? computedSubdirectory
-        )/swift-\(self.swiftVersion)/\(self.swiftDistributionName(platform: platform)).\(fileExtension)
+        )/\(computedSubdirectory)/\
+        swift-\(self.swiftVersion)/\(self.swiftDistributionName(platform: computedPlatform)).\(fileExtension)
         """
     )!
   }

Tests/SwiftSDKGeneratorTests/EndToEndTests.swift

@@ -462,17 +462,30 @@ final class Swift59_DebianEndToEndTests: XCTestCase {
     withDocker: false
   )
 
-  func testAarch64Direct() async throws {
+  func testBullseyeAarch64Direct() async throws {
     try skipSlow()
     try await buildTestcases(config: config.withArchitecture("aarch64"))
   }
 
-  func testX86_64Direct() async throws {
+  func testBullseyeX86_64Direct() async throws {
     try skipSlow()
     try await buildTestcases(config: config.withArchitecture("x86_64"))
   }
 
-  // NOTE: we do support building a Swift SDK from a pre-built Debian 11 Bullseye container
+  func testBookwormAarch64Direct() async throws {
+    try skipSlow()
+    try await buildTestcases(
+      config: config.withLinuxDistributionVersion("12").withArchitecture("aarch64"))
+  }
+
+  func testBookwormX86_64Direct() async throws {
+    try skipSlow()
+    try await buildTestcases(
+      config: config.withLinuxDistributionVersion("12").withArchitecture("x86_64"))
+  }
+
+  // NOTE: the generator does not support building a Debian 11/Debian 12 Swift SDK for
+  // Swift 5.9.x and 5.10 without a pre-built container, so we do not test this here.
 }
 
 final class Swift510_DebianEndToEndTests: XCTestCase {