HashTableIterators of empty hashtables are not poisoned upon destruction

Description

Using the zend_hash_iterators_* API, non-empty arrays are properly marked as poisoned in the HashTableIterator entries when destroyed.

However there is an edge case: if nNumUsed == 0 (thanks to deletion of entries during iteration), then the zend_hash_iterators_remove call is skipped in zend_hash_destroy.

Thus, we either should:
a) fix this by always calling the removal ... or
b) completely remove the auto-removal on destruction and leave it the extension authors responsibility to clear the iterators (making zend_hash_iterators_remove public API)

From the perspective of the code in php-src there is no need to have the auto-removal on free, as every iterating thing holds a reference to it.

PHP Version

master

Operating System

No response

zend_hash_destroy のパスを zend_hash_iterators_remove と併せて確認し、反復処理中の削除後に nNumUsed == 0 となるケースに注目してください。API が保証すべきイテレータのクリーンアップ動作を特定し、その後、空および空でないハッシュテーブルが期待される poisoned 状態を残すことを検証してください。