diff --git a/Objects/stringlib/formatter.h b/Objects/stringlib/formatter.h
index 5b7b3dc..7b29a9d 100644
--- a/Objects/stringlib/formatter.h
+++ b/Objects/stringlib/formatter.h
@@ -649,8 +649,8 @@
     case LT_DEFAULT_LOCALE:
         locale_info->decimal_point = ".";
         locale_info->thousands_sep = ",";
-        locale_info->grouping = "\3\0"; /* Group every 3 characters,
-                                         trailing 0 means repeat
+        locale_info->grouping = "\3"; /* Group every 3 characters.  The
+                                         (implicit) trailing 0 means repeat
                                          infinitely. */
         break;
     case LT_NO_LOCALE: