* Do not invoke link.exe with invalid args, execution

  with no arguments, will output the version string.
* Use proper path seperator based on running host for
  environment variable seperator.
* Check host arch to determine which subpath to check
  for visual studio installed binaries

Author: kcieplak

Sources/SWBCore/Core.swift

@@ -419,7 +419,7 @@ public final class Core: Sendable {
             }
         }
         if let additionalPlatformSearchPaths = getEnvironmentVariable("XCODE_EXTRA_PLATFORM_FOLDERS") {
-            for searchPath in additionalPlatformSearchPaths.split(separator: ":") {
+            for searchPath in additionalPlatformSearchPaths.split(separator: Path.pathEnvironmentSeparator) {
                 searchPaths.append(Path(searchPath))
             }
         }

Sources/SWBCore/Specs/Tools/LinkerTools.swift

@@ -1553,7 +1553,7 @@ public final class LibtoolLinkerSpec : GenericLinkerSpec, SpecIdentifierType, @u
 public func discoveredLinkerToolsInfo(_ producer: any CommandProducer, _ delegate: any CoreClientTargetDiagnosticProducingDelegate, at toolPath: Path) async -> (any DiscoveredCommandLineToolSpecInfo)? {
     do {
         do {
-            let commandLine = [toolPath.str,  producer.hostOperatingSystem == .windows ? "/VERSION" : "-version_details"]
+            let commandLine = [toolPath.str] + (producer.hostOperatingSystem == .windows ? [] : ["-version_details"])
             return try await producer.discoveredCommandLineToolSpecInfo(delegate, nil, commandLine, { executionResult in
                 let gnuLD = [
                     #/GNU ld version (?<version>[\d.]+)-.*/#,
@@ -1569,7 +1569,7 @@ public func discoveredLinkerToolsInfo(_ producer: any CommandProducer, _ delegat
                 if let match = try goLD.compactMap({ try $0.firstMatch(in: String(decoding: executionResult.stdout, as: UTF8.self)) }).first {
                     return DiscoveredLdLinkerToolSpecInfo(linker: .gold, toolPath: toolPath, toolVersion: try Version(String(match.output.version)), architectures: Set())
                 }
-                // link.exe has no option to simply dump the version, but if you pass an invalid argument, the program will dump a header that contains the version.
+                // link.exe has no option to simply dump the version, running, the program will no arguments will dump a header that contains the version.
                 let linkExe = [
                     #/Microsoft \(R\) Incremental Linker Version (?<version>[\d.]+)/#
                 ]

Sources/SWBTestSupport/TaskPlanningTestSupport.swift

@@ -210,7 +210,7 @@ open class MockTestTaskPlanningClientDelegate: TaskPlanningClientDelegate, @unch
             return .deferred
         case "ld" where args == ["-version_details"]:
              return .deferred
-        case "link" where args == ["/VERSION"]:
+        case "link":
             return .deferred
         case "libtool" where args == ["-V"] || args == ["--version"]:
             return .deferred

Sources/SWBWindowsPlatform/Plugin.swift

@@ -59,7 +59,11 @@ struct WindowsPlatformExtension: PlatformInfoExtension {
         guard let dir = try? await findLatestInstallDirectory(fs: fs) else {
             return []
         }
-        return [dir.join("bin/Hostarm64/arm64"), dir.join("bin/Hostx64/x64") ]
+        if Architecture.hostStringValue == "aarch64" {
+            return [dir.join("bin/Hostarm64/arm64")]
+        } else {
+            return [dir.join("bin/Hostx64/x64")]
+        }
    }
 }