Merge pull request swiftlang#1662 from swiftlang/revert-1560-android

Revert "SwiftDriver: initial work to properly handle android cross-compilation"

Author: hborla

Sources/SwiftDriver/Jobs/GenericUnixToolchain+LinkerSupport.swift

@@ -147,24 +147,14 @@ extension GenericUnixToolchain {
         }
       }
 
-      if targetInfo.sdkPath != nil {
-        for libpath in targetInfo.runtimeLibraryImportPaths {
-          commandLine.appendFlag(.L)
-          commandLine.appendPath(VirtualPath.lookup(libpath.path))
-        }
-      }
-
       if !isEmbeddedEnabled && !parsedOptions.hasArgument(.nostartfiles) {
-        let rsrc: VirtualPath
-        // 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)
-        }
-        let platform: String = targetTriple.platformName() ?? ""
-        let architecture: String = majorArchitectureName(for: targetTriple)
-        commandLine.appendPath(rsrc.appending(components: platform, architecture, "swiftrt.o"))
+        let swiftrtPath = VirtualPath.lookup(targetInfo.runtimeResourcePath.path)
+          .appending(
+            components: targetTriple.platformName() ?? "",
+            String(majorArchitectureName(for: targetTriple)),
+            "swiftrt.o"
+          )
+        commandLine.appendPath(swiftrtPath)
       }
 
       // If we are linking statically, we need to add all
@@ -204,12 +194,7 @@ extension GenericUnixToolchain {
         commandLine.appendPath(try VirtualPath(path: opt.argument.asSingle))
       }
 
-      if targetTriple.environment == .android {
-        if let sysroot = try getAndroidNDKSysrootPath() {
-          commandLine.appendFlag("--sysroot")
-          commandLine.appendPath(sysroot)
-        }
-      } else if let path = targetInfo.sdkPath?.path {
+      if let path = targetInfo.sdkPath?.path {
         commandLine.appendFlag("--sysroot")
         commandLine.appendPath(VirtualPath.lookup(path))
       }

Sources/SwiftDriver/Toolchains/GenericUnixToolchain.swift

@@ -117,50 +117,4 @@ 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)
-      }
-    }
-  }
 }

Sources/SwiftOptions/Options.swift

@@ -789,7 +789,6 @@ extension Option {
   public static let swiftVersion: Option = Option("-swift-version", .separate, attributes: [.frontend, .moduleInterface], metaVar: "<vers>", helpText: "Interpret input according to a specific Swift language version number")
   public static let switchCheckingInvocationThresholdEQ: Option = Option("-switch-checking-invocation-threshold=", .joined, attributes: [.helpHidden, .frontend, .noDriver])
   public static let symbolGraphMinimumAccessLevel: Option = Option("-symbol-graph-minimum-access-level", .separate, attributes: [.helpHidden, .frontend, .noInteractive, .supplementaryOutput], metaVar: "<level>", helpText: "Include symbols with this access level or more when emitting a symbol graph")
-  public static let sysroot: Option = Option("-sysroot", .separate, attributes: [.frontend, .argumentIsPath], metaVar: "<sysroot>", helpText: "Native Platform sysroot")
   public static let S: Option = Option("-S", .flag, alias: Option.emitAssembly, attributes: [.frontend, .noInteractive], group: .modes)
   public static let tabWidth: Option = Option("-tab-width", .separate, attributes: [.noInteractive, .noBatch, .indent], metaVar: "<n>", helpText: "Width of tab character.", group: .codeFormatting)
   public static let targetCpu: Option = Option("-target-cpu", .separate, attributes: [.frontend, .moduleInterface], helpText: "Generate code for a particular CPU variant")
@@ -1654,7 +1653,6 @@ extension Option {
       Option.swiftVersion,
       Option.switchCheckingInvocationThresholdEQ,
       Option.symbolGraphMinimumAccessLevel,
-      Option.sysroot,
       Option.S,
       Option.tabWidth,
       Option.targetCpu,