swiftPackages.swift-driver: fix patches that no longer apply cleanly

    })

  ];

  configurePhase = generated.configure + ''

    swiftpmMakeMutable swift-tools-support-core

    patch -p1 -d .build/checkouts/swift-tools-support-core -i ${

      fetchpatch {

        url = "https://github.com/apple/swift-tools-support-core/commit/990afca47e75cce136d2f59e464577e68a164035.patch";

        hash = "sha256-PLzWsp+syiUBHhEFS8+WyUcSae5p0Lhk7SSRdNvfouE=";

        includes = [ "Sources/TSCBasic/FileSystem.swift" ];

      }

    }

  '';

  configurePhase = generated.configure;

  # TODO: Tests depend on indexstore-db being provided by an existing Swift

  # toolchain. (ie. looks for `../lib/libIndexStore.so` relative to swiftc.

 import SwiftOptions

 import func TSCBasic.lookupExecutablePath

@@ -120,7 +121,18 @@

       // just using `clang` and avoid a dependency on the C++ runtime.

       let clangTool: Tool =

         parsedOptions.hasArgument(.enableExperimentalCxxInterop) ? .clangxx : .clang

@@ -130,7 +131,18 @@

       }

       let clangTool: Tool = cxxCompatEnabled ? .clangxx : .clang

-      var clangPath = try getToolPath(clangTool)

+

+      // For Nix, prefer linking using the wrapped Nixpkgs clang, instead of using

+      // we still want to use it for other purposes (clang importer).

+      var clangPath: AbsolutePath

+      if let binPath = try? AbsolutePath(validating: "@clang@/bin"),

+         let tool = lookupExecutablePath(filename: parsedOptions.hasArgument(.enableExperimentalCxxInterop)

+         let tool = lookupExecutablePath(filename: cxxCompatEnabled

+                                                        ? "clang++" : "clang",

+                                         searchPaths: [binPath]) {

+        clangPath = tool

       if let toolsDirPath = parsedOptions.getLastArgument(.toolsDirectory) {

         // FIXME: What if this isn't an absolute path?

         let toolsDir = try AbsolutePath(validating: toolsDirPath.asSingle)

@@ -136,6 +148,7 @@

@@ -146,6 +158,7 @@

         commandLine.appendFlag("-B")

         commandLine.appendPath(toolsDir)

       }