diff --git a/ChangeLog b/ChangeLog
index a5a04b7ef6..c62aae76bb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Fri Jun  5 06:43:00 2015  Eric Wong  <e@80x24.org>
+
+	* doc/extension.rdoc: note rb_get_kwargs changes keywords_hash
+	  [ruby-core:68507]
+
 Fri Jun  5 05:50:29 2015  Eric Wong  <e@80x24.org>
 
 	* ext/socket/ancdata.c (bsock_sendmsg_internal): use rb_scan_args
diff --git a/doc/extension.rdoc b/doc/extension.rdoc
index 0cb1d005a3..00e789f585 100644
--- a/doc/extension.rdoc
+++ b/doc/extension.rdoc
@@ -1401,7 +1401,8 @@ rb_scan_args(int argc, VALUE *argv, const char *fmt, ...) ::
 int rb_get_kwargs(VALUE keyword_hash, const ID *table, int required, int optional, VALUE *values)
 
   Retrieves argument VALUEs bound to keywords, which directed by +table+
-  into +values+.  First +required+ number of IDs referred by +table+ are
+  into +values+, deleting retrieved entries from +keyword_hash+ along
+  the way.  First +required+ number of IDs referred by +table+ are
   mandatory, and succeeding +optional+ (- +optional+ - 1 if
   +optional+ is negative) number of IDs are optional.  If a
   mandatory key is not contained in +keyword_hash+, raises "missing