Merge branch 'PHP-7.4'

* PHP-7.4:
  Fixed bug #79792

Author: nikic

Zend/tests/bug79792.phpt

@@ -0,0 +1,16 @@
+--TEST--
+Bug #79792: HT iterators not removed if empty array is destroyed
+--FILE--
+<?php
+$a = [42];
+foreach ($a as &$c) {
+    // Make the array empty.
+    unset($a[0]);
+    // Destroy the array.
+    $a = null;
+}
+?>
+===DONE===
+--EXPECTF--
+Warning: foreach() argument must be of type array|object, null given in %s on line %d
+===DONE===

Zend/zend_hash.c

@@ -1652,11 +1652,11 @@ ZEND_API void ZEND_FASTCALL zend_array_destroy(HashTable *ht)
 				}
 			} while (++p != end);
 		}
-		zend_hash_iterators_remove(ht);
-		SET_INCONSISTENT(HT_DESTROYED);
 	} else if (EXPECTED(HT_FLAGS(ht) & HASH_FLAG_UNINITIALIZED)) {
 		goto free_ht;
 	}
+	zend_hash_iterators_remove(ht);
+	SET_INCONSISTENT(HT_DESTROYED);
 	efree(HT_GET_DATA_ADDR(ht));
 free_ht:
 	FREE_HASHTABLE(ht);