review fixes

Author: hyp

Sources/SwiftDriver/Jobs/FrontendJobHelpers.swift

@@ -182,26 +182,6 @@ extension Driver {
     try commandLine.appendAll(.F, .Fsystem, from: &parsedOptions)
     try commandLine.appendAll(.vfsoverlay, from: &parsedOptions)
 
-    if targetTriple.environment == .android {
-        if let ndk = env["ANDROID_NDK_ROOT"] {
-            var sysroot: AbsolutePath =
-                try AbsolutePath(validating: ndk)
-                    .appending(components: "toolchains", "llvm", "prebuilt")
-#if arch(x86_64)
-#if os(Windows)
-                    .appending(component: "windows-x86_64")
-#elseif os(Linux)
-                    .appending(component: "linux-x86_64")
-#else
-                    .appending(component: "darwin-x86_64")
-#endif
-#endif
-                    .appending(component: "sysroot")
-            commandLine.appendFlag("-sysroot")
-            commandLine.appendFlag(sysroot.pathString)
-        }
-    }
-
     if let gccToolchain = parsedOptions.getLastArgument(.gccToolchain) {
         appendXccFlag("--gcc-toolchain=\(gccToolchain.asSingle)")
     }

Sources/SwiftDriver/Jobs/GenericUnixToolchain+LinkerSupport.swift

@@ -147,7 +147,7 @@ extension GenericUnixToolchain {
         }
       }
 
-      if let sdk = parsedOptions.getLastArgument(.sdk)?.asSingle ?? env["SDKROOT"], !sdk.isEmpty {
+      if targetInfo.sdkPath != nil {
         for libpath in targetInfo.runtimeLibraryImportPaths {
           commandLine.appendFlag(.L)
           commandLine.appendPath(VirtualPath.lookup(libpath.path))
@@ -156,10 +156,9 @@ extension GenericUnixToolchain {
 
       if !isEmbeddedEnabled && !parsedOptions.hasArgument(.nostartfiles) {
         let rsrc: VirtualPath
-        if let sdk = parsedOptions.getLastArgument(.sdk)?.asSingle ?? env["SDKROOT"], !sdk.isEmpty {
-          rsrc = try VirtualPath(path: AbsolutePath(validating: sdk)
-                                        .appending(components: "usr", "lib", "swift")
-                                        .pathString)
+        // Prefer the swiftrt.o runtime file from the SDK if it's specified.
+        if let sdk = targetInfo.sdkPath.flatMap({ VirtualPath.lookup($0.path) }) {
+          rsrc = sdk.appending(components: "usr", "lib", "swift")
         } else {
           rsrc = VirtualPath.lookup(targetInfo.runtimeResourcePath.path)
         }
@@ -206,20 +205,7 @@ extension GenericUnixToolchain {
       }
 
       if targetTriple.environment == .android {
-        if let ndk = env["ANDROID_NDK_ROOT"] {
-          var sysroot: AbsolutePath =
-                try AbsolutePath(validating: ndk)
-                    .appending(components: "toolchains", "llvm", "prebuilt")
-#if arch(x86_64)
-#if os(Windows)
-                    .appending(component: "windows-x86_64")
-#elseif os(Linux)
-                    .appending(component: "linux-x86_64")
-#else
-                    .appending(component: "darwin-x86_64")
-#endif
-#endif
-                    .appending(component: "sysroot")
+        if let sysroot = try getAndroidNDKSysrootPath() {
           commandLine.appendFlag("--sysroot")
           commandLine.appendPath(sysroot)
         }

Sources/SwiftDriver/Toolchains/GenericUnixToolchain.swift

@@ -117,4 +117,50 @@ public final class GenericUnixToolchain: Toolchain {
     let environment = (targetTriple.environment == .android) ? "-android" : ""
     return "libclang_rt.\(sanitizer.libraryName)-\(targetTriple.archName)\(environment).a"
   }
+
+  private func getAndroidNDKHostOSSuffix() -> String? {
+#if os(Windows)
+    "windows"
+#elseif os(Linux)
+    "linux"
+#elseif os(macOS)
+    "darwin"
+#else
+    // The NDK is only available on macOS, linux and windows hosts.
+    nil
+#endif
+  }
+
+  func getAndroidNDKSysrootPath() throws -> AbsolutePath? {
+#if arch(x86_64)
+    // The NDK's sysroot should be specified in the environment.
+    guard let ndk = env["ANDROID_NDK_ROOT"],
+          let osSuffix = getAndroidNDKHostOSSuffix() else {
+      return  nil
+    }
+    var sysroot: AbsolutePath =
+        try AbsolutePath(validating: ndk)
+            .appending(components: "toolchains", "llvm", "prebuilt")
+            .appending(component: "\(osSuffix)-x86_64")
+            .appending(component: "sysroot")
+    return sysroot
+#else
+    // The NDK is only available on an x86_64 host.
+    return nil
+#endif
+  }
+
+  public func addPlatformSpecificCommonFrontendOptions(
+    commandLine: inout [Job.ArgTemplate],
+    inputs: inout [TypedVirtualPath],
+    frontendTargetInfo: FrontendTargetInfo,
+    driver: inout Driver
+  ) throws {
+    if driver.targetTriple.environment == .android {
+      if let sysroot = try getAndroidNDKSysrootPath() {
+        commandLine.appendFlag("-sysroot")
+        commandLine.appendFlag(sysroot.pathString)
+      }
+    }
+  }
 }