1 files changed, 1 insertions, 0 deletions
diff --git a/enum.c b/enum.c
index ac86c9d550..0e4cf33d12 100644
--- a/enum.c
+++ b/enum.c
@@ -2010,6 +2010,7 @@ enum_zip(int argc, VALUE *argv, VALUE obj)
     if (!allary) {
 	CONST_ID(conv, "to_enum");
 	for (i=0; i<argc; i++) {
+	    if (!rb_respond_to(argv[i], id_each)) Check_Type(argv[i], T_ARRAY);
 	    argv[i] = rb_funcall(argv[i], conv, 1, ID2SYM(id_each));
 	}
     }