1 files changed, 2 insertions, 0 deletions
diff --git a/enum.c b/enum.c
index 0f5365e1a3..7f284481f6 100644
--- a/enum.c
+++ b/enum.c
@@ -2103,6 +2103,8 @@ enum_chunk(int argc, VALUE *argv, VALUE enumerable)
     VALUE initial_state;
     VALUE enumerator;
 
+    if(!rb_block_given_p())
+	rb_raise(rb_eArgError, "no block given");
     rb_scan_args(argc, argv, "01", &initial_state);
 
     enumerator = rb_obj_alloc(rb_cEnumerator);