diff --git a/Lib/test/test_warnings.py b/Lib/test/test_warnings.py
index 5c4fa59..e502ed8 100644
--- a/Lib/test/test_warnings.py
+++ b/Lib/test/test_warnings.py
@@ -530,6 +530,18 @@
         assert expected_line
         self.assertEqual(second_line, expected_line)
 
+    def test_filename_none(self):
+        # issue #12467: race condition if a warning is emitted at shutdown
+        globals_dict = globals()
+        oldfile = globals_dict['__file__']
+        try:
+            with original_warnings.catch_warnings(module=self.module) as w:
+                self.module.filterwarnings("always", category=UserWarning)
+                globals_dict['__file__'] = None
+                self.module.warn('test', UserWarning)
+        finally:
+            globals_dict['__file__'] = oldfile
+
 
 class WarningsDisplayTests(unittest.TestCase):
 
diff --git a/Misc/NEWS b/Misc/NEWS
index 16651ed..bbd1251 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -18,6 +18,9 @@
 Library
 -------
 
+- Issue #12467: warnings: fix a race condition if a warning is emitted at
+  shutdown, if globals()['__file__'] is None.
+
 - Issue #12352: Fix a deadlock in multiprocessing.Heap when a block is freed by
   the garbage collector while the Heap lock is held.
 
diff --git a/Python/_warnings.c b/Python/_warnings.c
index 88be7db..8456796 100644
--- a/Python/_warnings.c
+++ b/Python/_warnings.c
@@ -491,7 +491,7 @@
 
     /* Setup filename. */
     *filename = PyDict_GetItemString(globals, "__file__");
-    if (*filename != NULL) {
+    if (*filename != NULL && PyString_Check(*filename)) {
             Py_ssize_t len = PyString_Size(*filename);
         const char *file_str = PyString_AsString(*filename);
             if (file_str == NULL || (len < 0 && PyErr_Occurred()))