1 files changed, 1 insertions, 0 deletions
diff --git a/ext/thread/thread.c b/ext/thread/thread.c
index 7963d08066..09ece03f25 100644
--- a/ext/thread/thread.c
+++ b/ext/thread/thread.c
@@ -546,6 +546,7 @@ rb_szqueue_num_waiting(VALUE self)
 #define UNDER_THREAD 1
 #endif
 
+/* :nodoc: */
 static VALUE
 undumpable(VALUE obj)
 {