1 files changed, 5 insertions, 2 deletions
diff --git a/array.c b/array.c
index d154bf35e9..87044a856a 100644
--- a/array.c
+++ b/array.c
@@ -578,11 +578,14 @@ rb_ary_shift(VALUE ary)
     rb_ary_modify_check(ary);
     if (RARRAY_LEN(ary) == 0) return Qnil;
     top = RARRAY_PTR(ary)[0];
-    if (ARY_EMBED_P(ary)) {
+    if (RARRAY_LEN(ary) < ARY_DEFAULT_SIZE) {
 	MEMMOVE(RARRAY_PTR(ary), RARRAY_PTR(ary)+1, VALUE, RARRAY_LEN(ary));
-	ARY_SET_EMBED_LEN(ary, RARRAY_LEN(ary)-1);
+	ARY_SET_LEN(ary, RARRAY_LEN(ary)-1);
     }
     else {
+	if (!FL_TEST(ary, ELTS_SHARED)) {
+	    RARRAY(ary)->ptr[0] = Qnil;
+	}
 	ary_make_shared(ary);
 	RARRAY(ary)->as.heap.ptr++;	/* shift ptr */
 	RARRAY(ary)->as.heap.len--;