diff --git a/Lib/test/test_fcntl.py b/Lib/test/test_fcntl.py
index c8ea7b7..df09391 100644
--- a/Lib/test/test_fcntl.py
+++ b/Lib/test/test_fcntl.py
@@ -27,12 +27,8 @@
         else:
             start_len = "qq"
 
-    if sys.platform in ('netbsd1', 'netbsd2', 'netbsd3',
-                        'Darwin1.2', 'darwin',
-                        'freebsd2', 'freebsd3', 'freebsd4', 'freebsd5',
-                        'freebsd6', 'freebsd7', 'freebsd8',
-                        'bsdos2', 'bsdos3', 'bsdos4',
-                        'openbsd', 'openbsd2', 'openbsd3', 'openbsd4'):
+    if (sys.platform.startswith(('netbsd', 'freebsd', 'openbsd', 'bsdos'))
+        or sys.platform == 'darwin'):
         if struct.calcsize('l') == 8:
             off_t = 'l'
             pid_t = 'i'
diff --git a/Misc/NEWS b/Misc/NEWS
index 0701d6f..a5bc4ae 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -183,6 +183,8 @@
 Tests
 -----
 
+- Issue #12821: Fix test_fcntl failures on OpenBSD 5.
+
 - Issue #12331: The test suite for lib2to3 can now run from an installed
   Python.