Exercise bootstrapping with the XCBuild codepath in build-using-self

Utilities/bootstrap

@@ -87,6 +87,10 @@ def add_global_args(parser):
 def add_build_args(parser):
     """Configures the parser with the arguments necessary for build-related actions."""
     add_global_args(parser)
+    parser.add_argument(
+        "--swift-build-path",
+        help="path to the prebuilt SwiftPM `swift-build` binary",
+        metavar="PATH")
     parser.add_argument(
         "--swiftc-path",
         help="path to the swift compiler",
@@ -154,7 +158,7 @@ def add_build_args(parser):
         default=[])
     parser.add_argument(
         "--cross-compile-config",
-        help="Swift flags to cross-compile SPM with itself")
+        help="Swift flags to cross-compile SwiftPM with itself")
 
 def add_test_args(parser):
     """Configures the parser with the arguments necessary for the test action."""
@@ -220,8 +224,9 @@ def parse_build_args(args):
 
     args.swiftc_path = get_swiftc_path(args)
     args.clang_path = get_tool_path(args, "clang")
-    args.cmake_path = get_tool_path(args, "cmake")
-    args.ninja_path = get_tool_path(args, "ninja")
+    if not args.skip_cmake_bootstrap:
+        args.cmake_path = get_tool_path(args, "cmake")
+        args.ninja_path = get_tool_path(args, "ninja")
     args.ar_path = get_tool_path(args, "ar")
     args.ranlib_path = get_tool_path(args, "ranlib")
     if args.cross_compile_hosts:
@@ -640,7 +645,7 @@ def build_swiftpm_with_swiftpm(args, integrated_swift_driver):
         swiftpm_args.append(os.path.join(args.bootstrap_dir, "bin/swift-bootstrap"))
     else:
         note("Building SwiftPM (with a prebuilt swift-build)")
-        swiftpm_args.append(os.path.join(os.path.split(args.swiftc_path)[0], "swift-build"))
+        swiftpm_args.append(args.swift_build_path or os.path.join(os.path.split(args.swiftc_path)[0], "swift-build"))
         swiftpm_args.append("--disable-sandbox")
 
         # Enforce resolved versions to avoid stray dependencies that aren't local.

Utilities/build-using-self

@@ -34,3 +34,13 @@ cd IntegrationTests
 # Perform package update in order to get the latest commits for the dependencies.
 swift package update
 $SWIFTPM_BIN_DIR/swift-test --parallel
+
+if [ "$(uname)" == "Darwin" ]; then
+  cd ..
+  echo "Current working directory is ${PWD}"
+  echo "Bootstrapping with the XCBuild codepath..."
+  ./Utilities/bootstrap build --release \
+    --cross-compile-hosts macosx-arm64 \
+    --skip-cmake-bootstrap \
+    --swift-build-path "${SWIFTPM_BIN_DIR}/swift-build"
+fi