Index: utils/lit/lit/TestRunner.py
===================================================================
--- utils/lit/lit/TestRunner.py
+++ utils/lit/lit/TestRunner.py
@@ -350,7 +350,7 @@
             lit.util.mkdir_p(dir)
         else:
             try:
-                os.mkdir(dir)
+                lit.util.mkdir(dir)
             except OSError as err:
                 stderr.write("Error: 'mkdir' command failed, %s\n" % str(err))
                 exitCode = 1
@@ -607,7 +607,51 @@
                 if not recursive:
                     stderr.write("Error: %s is a directory\n" % path)
                     exitCode = 1
-                shutil.rmtree(path, onerror = on_rm_error if force else None)
+
+                if platform.system() == 'Windows':
+                    # NOTE: use ctypes to access `SHFileOperationW` on Windows
+                    # to use the NT style path to get access to long file paths
+                    # which cannot be removed otherwise.
+                    from ctypes.wintypes import BOOL, HWND, LPCWSTR, POINTER, UINT, WORD
+                    from ctypes import c_void_p, byref
+                    from ctypes import Structure
+                    from ctypes import windll, WinError
+
+                    class SHFILEOPSTRUCTW(Structure):
+                        _fields_ = [
+                                ('hWnd', HWND),
+                                ('wFunc', UINT),
+                                ('pFrom', LPCWSTR),
+                                ('pTo', LPCWSTR),
+                                ('fFlags', WORD),
+                                ('fAnyOperationsAborted', BOOL),
+                                ('hNameMappings', c_void_p),
+                                ('lpszProgressTitle', LPCWSTR),
+                        ]
+
+                    FO_MOVE, FO_COPY, FO_DELETE, FO_RENAME = xrange(1, 5)
+
+                    FOF_SILENT = 4
+                    FOF_NOCONFIRMATION = 16
+                    FOF_NOCONFIRMMKDIR = 512
+                    FOF_NOERRORUI = 1024
+
+                    FOF_NO_UI = FOF_SILENT | FOF_NOCONFIRMATION | FOF_NOERRORUI | FOF_NOCONFIRMMKDIR
+
+                    SHFileOperationW = windll.shell32.SHFileOperationW
+                    SHFileOperationW.argtypes = [POINTER(SHFILEOPSTRUCTW)]
+
+                    path = os.path.abspath(path)
+
+                    operation = SHFILEOPSTRUCTW(wFunc=UINT(FO_DELETE),
+                                                pFrom=LPCWSTR(unicode(path + '\0')),
+                                                fFlags=FOF_NO_UI)
+                    result = SHFileOperationW(byref(operation))
+                    if result:
+                        raise WinError(result)
+                else:
+                    shutil.rmtree(path, onerror = on_rm_error if force else None)
+
             else:
                 if force and not os.access(path, os.W_OK):
                     os.chmod(path,
Index: utils/lit/lit/util.py
===================================================================
--- utils/lit/lit/util.py
+++ utils/lit/lit/util.py
@@ -128,6 +128,25 @@
     return 1  # Default
 
 
+def mkdir(path):
+    try:
+        if platform.system() == 'Windows':
+            from ctypes import windll
+            from ctypes import GetLastError, WinError
+
+            path = os.path.abspath(path)
+            NTPath = unicode(r'\\?\%s' % path)
+            if not windll.CreateDirectoryW(NTPath, None):
+                raise WinError(GetLastError())
+        else:
+            os.mkdir(path)
+    except OSError:
+        e = sys.exc_info()[1]
+        # ignore EEXIST, which may occur during a race condition
+        if e.errno != errno.EEXIST:
+            raise
+
+
 def mkdir_p(path):
     """mkdir_p(path) - Make the "path" directory, if it does not exist; this
     will also make directories for any missing parent directories."""
@@ -138,13 +157,7 @@
     if parent != path:
         mkdir_p(parent)
 
-    try:
-        os.mkdir(path)
-    except OSError:
-        e = sys.exc_info()[1]
-        # Ignore EEXIST, which may occur during a race condition.
-        if e.errno != errno.EEXIST:
-            raise
+    mkdir(path)
 
 
 def listdir_files(dirname, suffixes=None, exclude_filenames=None):