diff --git a/Lib/test/libregrtest/cmdline.py b/Lib/test/libregrtest/cmdline.py
index 538ff05..0927032 100644
--- a/Lib/test/libregrtest/cmdline.py
+++ b/Lib/test/libregrtest/cmdline.py
@@ -271,7 +271,8 @@
     group.add_argument('--junit-xml', dest='xmlpath', metavar='FILENAME',
                        help='writes JUnit-style XML results to the specified '
                             'file')
-
+    group.add_argument('--tempdir', dest='tempdir', metavar='PATH',
+                       help='override the working directory for the test run')
     return parser
 
 
@@ -383,8 +384,7 @@
     if ns.match_filename:
         if ns.match_tests is None:
             ns.match_tests = []
-        filename = os.path.join(support.SAVEDCWD, ns.match_filename)
-        with open(filename) as fp:
+        with open(ns.match_filename) as fp:
             for line in fp:
                 ns.match_tests.append(line.strip())
 
diff --git a/Lib/test/libregrtest/main.py b/Lib/test/libregrtest/main.py
index 1fd4132..a8d27ae 100644
--- a/Lib/test/libregrtest/main.py
+++ b/Lib/test/libregrtest/main.py
@@ -550,12 +550,12 @@
 
     def main(self, tests=None, **kwargs):
         global TEMPDIR
+        self.ns = self.parse_args(kwargs)
 
-        if sysconfig.is_python_build():
-            try:
-                os.mkdir(TEMPDIR)
-            except FileExistsError:
-                pass
+        if self.ns.tempdir:
+            TEMPDIR = self.ns.tempdir
+
+        os.makedirs(TEMPDIR, exist_ok=True)
 
         # Define a writable temp dir that will be used as cwd while running
         # the tests. The name of the dir includes the pid to allow parallel
@@ -571,8 +571,6 @@
             self._main(tests, kwargs)
 
     def _main(self, tests, kwargs):
-        self.ns = self.parse_args(kwargs)
-
         if self.ns.huntrleaks:
             warmup, repetitions, _ = self.ns.huntrleaks
             if warmup < 1 or repetitions < 1: