diff --git a/ext/standard/array.c b/ext/standard/array.c
index 47ea40325b5..d95ea012ad6 100644
--- a/ext/standard/array.c
+++ b/ext/standard/array.c
@@ -3632,7 +3632,8 @@ PHP_FUNCTION(array_shift)
 			}
 			idx++;
 		}
-		RETVAL_COPY_DEREF(val);
+		RETVAL_COPY_VALUE(val);
+		ZVAL_UNDEF(val);
 
 		/* Delete the first value */
 		zend_hash_packed_del_val(Z_ARRVAL_P(stack), val);
@@ -3686,7 +3687,8 @@ PHP_FUNCTION(array_shift)
 			}
 			idx++;
 		}
-		RETVAL_COPY_DEREF(val);
+		RETVAL_COPY_VALUE(val);
+		ZVAL_UNDEF(val);
 
 		/* Delete the first value */
 		zend_hash_del_bucket(Z_ARRVAL_P(stack), p);
@@ -3710,6 +3712,10 @@ PHP_FUNCTION(array_shift)
 	}
 
 	zend_hash_internal_pointer_reset(Z_ARRVAL_P(stack));
+
+	if (Z_ISREF_P(return_value)) {
+		zend_unwrap_reference(return_value);
+	}
 }
 /* }}} */
 
diff --git a/ext/standard/tests/array/gh16957.phpt b/ext/standard/tests/array/gh16957.phpt
new file mode 100644
index 00000000000..a716228249e
--- /dev/null
+++ b/ext/standard/tests/array/gh16957.phpt
@@ -0,0 +1,41 @@
+--TEST--
+GH-16957 (Assertion failure in array_shift with self-referencing array)
+--FILE--
+<?php
+$new_array = array(&$new_array, 1, 'two');
+var_dump($shifted = array_shift($new_array));
+var_dump($new_array);
+var_dump($new_array === $shifted);
+
+$new_array2 = array(&$new_array2, 2 => 1, 300 => 'two');
+var_dump($shifted = array_shift($new_array2));
+var_dump($new_array2);
+var_dump($new_array2 === $shifted);
+?>
+--EXPECT--
+array(2) {
+  [0]=>
+  int(1)
+  [1]=>
+  string(3) "two"
+}
+array(2) {
+  [0]=>
+  int(1)
+  [1]=>
+  string(3) "two"
+}
+bool(true)
+array(2) {
+  [0]=>
+  int(1)
+  [1]=>
+  string(3) "two"
+}
+array(2) {
+  [0]=>
+  int(1)
+  [1]=>
+  string(3) "two"
+}
+bool(true)