diff -r 01417ca7f2e2 -r ba7eaff26474 contrib/check-py3-compat.py
--- a/contrib/check-py3-compat.py	Mon Feb 04 14:25:00 2019 -0800
+++ b/contrib/check-py3-compat.py	Mon Feb 04 14:38:23 2019 -0800
@@ -14,6 +14,7 @@
 import os
 import sys
 import traceback
+import warnings
 
 def check_compat_py2(f):
     """Check Python 3 compatibility for a file with Python 2"""
@@ -91,6 +92,11 @@
         fn = check_compat_py3
 
     for f in sys.argv[1:]:
-        fn(f)
+        with warnings.catch_warnings(record=True) as warns:
+            fn(f)
+
+        for w in warns:
+            print(warnings.formatwarning(w.message, w.category,
+                                         w.filename, w.lineno).rstrip())
 
     sys.exit(0)