fixed #5984 and improved test coverage
diff --git a/Misc/NEWS b/Misc/NEWS
index a01b454..f560bd8 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -285,6 +285,9 @@
 Library
 -------
 
+- Issue #5984: distutils.command.build_ext.check_extensions_list checks were broken
+  for old-style extensions.
+
 - Issue #5971: StreamHandler.handleError now swallows IOErrors which occur when
   trying to print a traceback.