diff --git a/CMakeLists.txt b/CMakeLists.txt
index a961063c..60dcc644 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -123,7 +123,6 @@ if(ENABLE_TESTING)
 
   find_package(Python3 COMPONENTS Interpreter REQUIRED)
 
-  string(REPLACE "\\" "\\\\" CMAKE_Swift_FLAGS_ESCAPED ${CMAKE_Swift_FLAGS})
   add_custom_target(check-xctest
                     COMMAND
                     ${CMAKE_COMMAND} -E env
@@ -133,7 +132,6 @@ if(ENABLE_TESTING)
                       LIBDISPATCH_BUILD_DIR=${XCTEST_PATH_TO_LIBDISPATCH_BUILD}
                       LIBDISPATCH_OVERLAY_DIR=${XCTEST_PATH_TO_LIBDISPATCH_BUILD}/src/swift
                       SWIFT_EXEC=${CMAKE_Swift_COMPILER}
-                      SWIFT_FLAGS=${CMAKE_Swift_FLAGS_ESCAPED}
                       $<TARGET_FILE:Python3::Interpreter> ${LIT_COMMAND} -sv ${CMAKE_SOURCE_DIR}/Tests/Functional
                     COMMENT
                       "Running XCTest functional test suite"
diff --git a/Tests/Functional/lit.cfg b/Tests/Functional/lit.cfg
index 52575109..6775fb8d 100644
--- a/Tests/Functional/lit.cfg
+++ b/Tests/Functional/lit.cfg
@@ -78,7 +78,7 @@ else:
     if platform.system() == 'Windows':
         sdkroot = os.getenv('SDKROOT', None)
         if sdkroot:
-            swift_exec.extend(['-sdk', sdkroot])
+            swift_exec.extend(['-sdk', '"' + sdkroot + '"'])
         swift_exec.extend(['-Xlinker', '-nodefaultlib:libcmt'])
     else:
         swift_exec.extend([
@@ -88,42 +88,36 @@ else:
           '-Xlinker', '-rpath', '-Xlinker', os.path.join(foundation_dir, 'Sources', 'FoundationNetworking'),
           '-Xlinker', '-rpath', '-Xlinker', os.path.join(foundation_dir, 'Sources', 'FoundationXML'),
           '-Xlinker', '-rpath', '-Xlinker', os.path.join(foundation_dir, 'lib'),
+          '-L', foundation_dir,
+          '-L', os.path.join(foundation_dir, 'Foundation'),
+          '-L', os.path.join(foundation_dir, 'Sources', 'Foundation'),
+          '-L', os.path.join(foundation_dir, 'Sources', 'FoundationNetworking'),
+          '-L', os.path.join(foundation_dir, 'Sources', 'FoundationXML'),
+          '-L', os.path.join(foundation_dir, 'lib'),
+          '-I', foundation_dir,
+          '-I', os.path.join(foundation_dir, 'swift'),
+          '-I', os.path.join(foundation_dir, '_CModulesForClients'),
+          '-Xcc', '-F', '-Xcc', foundation_dir,
         ])
-    swift_exec.extend([
-        '-L', foundation_dir,
-        '-L', os.path.join(foundation_dir, 'Foundation'),
-        '-L', os.path.join(foundation_dir, 'Sources', 'Foundation'),
-        '-L', os.path.join(foundation_dir, 'Sources', 'FoundationNetworking'),
-        '-L', os.path.join(foundation_dir, 'Sources', 'FoundationXML'),
-        '-L', os.path.join(foundation_dir, 'lib'),
-        '-I', foundation_dir,
-        '-I', os.path.join(foundation_dir, 'swift'),
-        '-I', os.path.join(foundation_dir, '_CModulesForClients'),
-        '-Xcc', '-F', '-Xcc', foundation_dir,
-    ])
-
-    # We also need to link swift-corelibs-libdispatch, if
-    # swift-corelibs-foundation is using it.
-    libdispatch_src_dir = os.getenv('LIBDISPATCH_SRC_DIR')
-    libdispatch_build_dir = os.getenv('LIBDISPATCH_BUILD_DIR')
-    libdispatch_overlay_dir = os.getenv('LIBDISPATCH_OVERLAY_DIR')
-    if ((libdispatch_src_dir is not None) 
-        and (libdispatch_build_dir is not None)
-        and (libdispatch_overlay_dir is not None)):
-            swift_exec.extend([
-                '-Xcc', '-fblocks',
-                '-I', libdispatch_src_dir,
-                '-I', libdispatch_overlay_dir,
-                '-I', os.path.join(libdispatch_overlay_dir, 'swift'),
-                '-L', libdispatch_build_dir,
-                '-L', os.path.join(libdispatch_build_dir, 'src'),
-                '-L', os.path.join(libdispatch_build_dir, 'src', 'BlocksRuntime'),
-                '-L', os.path.join(libdispatch_build_dir, 'src', 'swift'),
-                '-vfsoverlay', os.path.join(libdispatch_build_dir, 'dispatch-vfs-overlay.yaml'),
-            ])
 
-            if platform.system() != 'Windows':
+        # We also need to link swift-corelibs-libdispatch, if
+        # swift-corelibs-foundation is using it.
+        libdispatch_src_dir = os.getenv('LIBDISPATCH_SRC_DIR')
+        libdispatch_build_dir = os.getenv('LIBDISPATCH_BUILD_DIR')
+        libdispatch_overlay_dir = os.getenv('LIBDISPATCH_OVERLAY_DIR')
+        if ((libdispatch_src_dir is not None)
+            and (libdispatch_build_dir is not None)
+            and (libdispatch_overlay_dir is not None)):
                 swift_exec.extend([
+                    '-Xcc', '-fblocks',
+                    '-I', libdispatch_src_dir,
+                    '-I', libdispatch_overlay_dir,
+                    '-I', os.path.join(libdispatch_overlay_dir, 'swift'),
+                    '-L', libdispatch_build_dir,
+                    '-L', os.path.join(libdispatch_build_dir, 'src'),
+                    '-L', os.path.join(libdispatch_build_dir, 'src', 'BlocksRuntime'),
+                    '-L', os.path.join(libdispatch_build_dir, 'src', 'swift'),
+                    '-vfsoverlay', os.path.join(libdispatch_build_dir, 'dispatch-vfs-overlay.yaml'),
                     '-Xlinker', '-rpath', '-Xlinker', libdispatch_build_dir,
                 ])