[Explicit Module Build] Correctly discern libSwiftScan location in the os-specific directory of the toolchain

Author: artemcm

Sources/SwiftDriver/ExplicitModuleBuilds/InterModuleDependencies/InterModuleDependencyOracle.swift

@@ -54,24 +54,26 @@ public class InterModuleDependencyOracle {
 
   /// Given a specified toolchain path, locate and instantiate an instance of the SwiftScan library
   @_spi(Testing) public func verifyOrCreateScannerInstance(fileSystem: FileSystem,
-                                                           toolchainPath: AbsolutePath) throws {
+                                                           toolchainPath: AbsolutePath,
+                                                           osName: String) throws {
     try queue.sync {
+      let swiftScanLibPath = toolchainPath.appending(component: "lib")
+        .appending(component: "swift")
+        .appending(component: osName)
+        .appending(component: "lib_InternalSwiftScan.dylib")
       if swiftScanLibInstance == nil {
         guard fileSystem.exists(toolchainPath) else {
           fatalError("Path to specified toolchain does not exist: \(toolchainPath.description)")
         }
-
-        let swiftScanLibPath = toolchainPath.appending(component: "lib")
-          .appending(component: "lib_InternalSwiftScan.dylib")
         guard fileSystem.exists(toolchainPath) else {
           fatalError("Could not find libSwiftScan at: \(swiftScanLibPath.description)")
         }
-
         swiftScanLibInstance = try SwiftScan(dylib: swiftScanLibPath)
       } else {
-        let swiftScanLibPath = toolchainPath.appending(component: "lib")
-          .appending(component: "lib_InternalSwiftScan.dylib")
-        assert(swiftScanLibInstance!.path == swiftScanLibPath)
+        guard swiftScanLibInstance!.path == swiftScanLibPath else {
+          throw DependencyScanningError
+          .scanningLibraryInvocationMismatch(swiftScanLibInstance!.path, swiftScanLibPath)
+        }
       }
     }
   }

Sources/SwiftDriver/ExplicitModuleBuilds/ModuleDependencyScanning.swift

@@ -94,9 +94,10 @@ internal extension Driver {
     let dependencyGraph: InterModuleDependencyGraph
 
     if (!parsedOptions.hasArgument(.driverScanDependenciesNonLib)) {
-      try interModuleDependencyOracle.verifyOrCreateScannerInstance(fileSystem: fileSystem,
-                                                                    toolchainPath:
-                                                                      try getRootPath(of: toolchain))
+      try interModuleDependencyOracle
+        .verifyOrCreateScannerInstance(fileSystem: fileSystem,
+                                       toolchainPath: try getRootPath(of: toolchain),
+                                       osName: targetTriple.osNameUnversioned)
       let cwd = workingDirectory ?? fileSystem.currentWorkingDirectory!
       var command = try itemizedJobCommand(of: scannerJob,
                                            forceResponseFiles: forceResponseFiles,
@@ -127,9 +128,10 @@ internal extension Driver {
 
     let moduleVersionedGraphMap: [ModuleDependencyId: [InterModuleDependencyGraph]]
     if (!parsedOptions.hasArgument(.driverScanDependenciesNonLib)) {
-      try interModuleDependencyOracle.verifyOrCreateScannerInstance(fileSystem: fileSystem,
-                                                                    toolchainPath:
-                                                                      try getRootPath(of: toolchain))
+      try interModuleDependencyOracle
+        .verifyOrCreateScannerInstance(fileSystem: fileSystem,
+                                       toolchainPath: try getRootPath(of: toolchain),
+                                       osName: targetTriple.osNameUnversioned)
       let cwd = workingDirectory ?? fileSystem.currentWorkingDirectory!
       var command = try itemizedJobCommand(of: batchScanningJob,
                                            forceResponseFiles: forceResponseFiles,

Sources/SwiftDriver/SwiftScan/SwiftScan.swift

@@ -24,6 +24,7 @@ public enum DependencyScanningError: Error, DiagnosticData {
   case moduleNameDecodeFailure(String)
   case unsupportedDependencyDetailsKind(Int)
   case invalidStringPtr
+  case scanningLibraryInvocationMismatch(AbsolutePath, AbsolutePath)
 
   public var description: String {
     switch self {
@@ -41,6 +42,8 @@ public enum DependencyScanningError: Error, DiagnosticData {
         return "Dependency module details field kind not supported: `\(kindRawValue)`"
       case .invalidStringPtr:
         return "Dependency module details contains a corrupted string reference"
+      case .scanningLibraryInvocationMismatch(let path1, let path2):
+        return "Module scanning library differs across driver invocations: \(path1.description) and \(path2.description)"
     }
   }
 }

Sources/SwiftDriver/Utilities/Triple.swift

@@ -1522,6 +1522,20 @@ extension Triple {
 
     return Version(parse: osName)
   }
+
+  public var osNameUnversioned: String {
+    var canonicalOsName = self.osName[...]
+
+    // Assume that the OS portion of the triple starts with the canonical name.
+    if let os = os {
+      if canonicalOsName.hasPrefix(os.name) {
+        canonicalOsName = osName.prefix(os.name.count)
+      } else if os == .macosx, osName.hasPrefix("macos") {
+        canonicalOsName = osName.prefix(5)
+      }
+    }
+    return String(canonicalOsName)
+  }
 }
 
 // MARK: - Darwin Versions

Tests/SwiftDriverTests/ExplicitModuleBuildTests.swift

@@ -164,8 +164,10 @@ final class ExplicitModuleBuildTests: XCTestCase {
                                                               .parentDirectory // bin
                                                               .parentDirectory // toolchain root
       let dependencyOracle = InterModuleDependencyOracle()
-      try dependencyOracle.verifyOrCreateScannerInstance(fileSystem: localFileSystem,
-                                                         toolchainPath: toolchainRootPath)
+      try dependencyOracle
+        .verifyOrCreateScannerInstance(fileSystem: localFileSystem,
+                                       toolchainPath: toolchainRootPath,
+                                       osName: driver.targetTriple.osNameUnversioned)
       try dependencyOracle.mergeModules(from: moduleDependencyGraph)
       driver.explicitDependencyBuildPlanner =
         try ExplicitDependencyBuildPlanner(dependencyGraph: moduleDependencyGraph,
@@ -225,8 +227,6 @@ final class ExplicitModuleBuildTests: XCTestCase {
                                                               .parentDirectory // bin
                                                               .parentDirectory // toolchain root
       let dependencyOracle = InterModuleDependencyOracle()
-      try dependencyOracle.verifyOrCreateScannerInstance(fileSystem: localFileSystem,
-                                                         toolchainPath: toolchainRootPath)
       try dependencyOracle.mergeModules(from: inputDependencyGraph)
 
       // Construct a module dependency graph that will contain .swiftPlaceholder("B"),
@@ -243,7 +243,10 @@ final class ExplicitModuleBuildTests: XCTestCase {
       var driver = try Driver(args: commandLine, executor: executor,
                               externalBuildArtifacts: (targetModulePathMap, [:]),
                               interModuleDependencyOracle: dependencyOracle)
-
+      try dependencyOracle
+        .verifyOrCreateScannerInstance(fileSystem: localFileSystem,
+                                       toolchainPath: toolchainRootPath,
+                                       osName: driver.targetTriple.osNameUnversioned)
 
       // Plan explicit dependency jobs, after resolving placeholders to actual dependencies.
       try moduleDependencyGraph.resolvePlaceholderDependencies(for: (targetModulePathMap, [:]),
@@ -523,9 +526,11 @@ final class ExplicitModuleBuildTests: XCTestCase {
     // The dependency oracle wraps an instance of libSwiftScan and ensures thread safety across
     // queries.
     let dependencyOracle = InterModuleDependencyOracle()
-    try dependencyOracle.verifyOrCreateScannerInstance(fileSystem: localFileSystem,
-                                                       toolchainPath: toolchainRootPath)
-
+    try dependencyOracle
+      .verifyOrCreateScannerInstance(fileSystem: localFileSystem,
+                                     toolchainPath: toolchainRootPath,
+                                     osName: driver.targetTriple.osNameUnversioned)
+    
     // Create a simple test case.
     try withTemporaryDirectory { path in
       let main = path.appending(component: "testDependencyScanning.swift")