diff -r b7a75b9a3386 -r 0407a51b9d8c mercurial/sparse.py
--- a/mercurial/sparse.py	Tue Jul 11 08:52:55 2017 -0700
+++ b/mercurial/sparse.py	Fri Jul 14 14:22:40 2017 -0700
@@ -106,7 +106,7 @@
                     "in rev %s - ignoring it\n" % (profile, ctx))
                 # experimental config: sparse.missingwarning
                 if repo.ui.configbool(
-                        'sparse', 'missingwarning', True):
+                        'sparse', 'missingwarning'):
                     repo.ui.warn(msg)
                 else:
                     repo.ui.debug(msg)