diff --git a/Documentation/conf.py b/Documentation/conf.py
index db16814f182f..37314afd1ac8 100644
--- a/Documentation/conf.py
+++ b/Documentation/conf.py
@@ -343,9 +343,10 @@ sys.stderr.write("Using %s theme\n" % html_theme)
 # so a file named "default.css" will overwrite the builtin "default.css".
 html_static_path = ['sphinx-static']
 
-# If true, SmartyPants will be used to convert quotes and dashes to
-# typographically correct entities.
-html_use_smartypants = False
+# If true, Docutils "smart quotes" will be used to convert quotes and dashes
+# to typographically correct entities.  This will convert "--" to "—",
+# which is not always what we want, so disable it.
+smartquotes = False
 
 # Custom sidebar templates, maps document names to template names.
 # Note that the RTD theme ignores this