Merge branch 'PHP-7.3' into PHP-7.4

* PHP-7.3:
  Detect self-addition of array more accurately
  Deindirect source elements in zend_hash_merge

diff --cc Zend/zend_hash.c
Simple merge

diff --cc Zend/zend_operators.c
index 08fc18f2614836e85d167522d5fbf273f9a92f74,7338e471b65bed2337f76593507825a6ffb96763..596581270b047098675dc13afe79c05b995a1a74
--- 1/Zend/zend_operators.c
--- 2/Zend/zend_operators.c
+++ b/Zend/zend_operators.c
@@@ -920,21 -901,9 +920,21 @@@ try_again
  }
  /* }}} */
  
 +ZEND_API zend_string* ZEND_FASTCALL zval_get_string_func(zval *op) /* {{{ */
 +{
 +      return __zval_get_string_func(op, 0);
 +}
 +/* }}} */
 +
 +ZEND_API zend_string* ZEND_FASTCALL zval_try_get_string_func(zval *op) /* {{{ */
 +{
 +      return __zval_get_string_func(op, 1);
 +}
 +/* }}} */
 +
  static zend_never_inline void ZEND_FASTCALL add_function_array(zval *result, zval *op1, zval *op2) /* {{{ */
  {
-       if ((result == op1) && (result == op2)) {
+       if (result == op1 && Z_ARR_P(op1) == Z_ARR_P(op2)) {
                /* $a += $a */
                return;
        }