Patch #404680: disables the nis module and enables the dl module when
    building under Cygwin.  Makes some fixes to the dlmodule in order to
    compile with Cygwin.
diff --git a/Lib/test/test_dl.py b/Lib/test/test_dl.py
index 60a5cf0..390dbd8 100755
--- a/Lib/test/test_dl.py
+++ b/Lib/test/test_dl.py
@@ -9,6 +9,7 @@
 sharedlibs = [
     ('/usr/lib/libc.so', 'getpid'),
     ('/lib/libc.so.6', 'getpid'),
+    ('/usr/bin/cygwin1.dll', 'getpid'),
     ]
 
 for s, func in sharedlibs: