Use zval_ptr_dtor() to replace bound variables (original values nay be circular structures).

Author: dstogov

ext/mysqlnd/mysqlnd_ps.c

@@ -799,7 +799,7 @@ mysqlnd_stmt_fetch_row_buffered(MYSQLND_RES * result, void * param, const unsign
 					ZVAL_DEREF(result);
 					/* Clean what we copied last time */
 #ifndef WE_DONT_COPY_IN_BUFFERED_AND_UNBUFFERED_BECAUSEOF_IS_REF
-					zval_dtor(result);
+					zval_ptr_dtor(result);
 #endif
 					/* copy the type */
 					if (stmt->result_bind[i].bound == TRUE) {
@@ -909,7 +909,7 @@ mysqlnd_stmt_fetch_row_unbuffered(MYSQLND_RES * result, void * param, const unsi
 					  in result->unbuf->m.free_last_data()
 					*/
 #ifndef WE_DONT_COPY_IN_BUFFERED_AND_UNBUFFERED_BECAUSEOF_IS_REF
-					zval_dtor(result);
+					zval_ptr_dtor(result);
 #endif
 					if (!Z_ISNULL_P(data)) {
 						if ((Z_TYPE_P(data) == IS_STRING) && (meta->fields[i].max_length < (zend_ulong) Z_STRLEN_P(data))){
@@ -1094,7 +1094,7 @@ mysqlnd_fetch_stmt_row_cursor(MYSQLND_RES * result, void * param, const unsigned
 					  in result->unbuf->m.free_last_data()
 					*/
 #ifndef WE_DONT_COPY_IN_BUFFERED_AND_UNBUFFERED_BECAUSEOF_IS_REF
-					zval_dtor(result);
+					zval_ptr_dtor(result);
 #endif
 					DBG_INF_FMT("i=%u bound_var=%p type=%u refc=%u", i, &stmt->result_bind[i].zv,
 								Z_TYPE_P(data), Z_REFCOUNTED(stmt->result_bind[i].zv)?
@@ -1203,7 +1203,7 @@ MYSQLND_METHOD(mysqlnd_stmt, fetch)(MYSQLND_STMT * const s, zend_bool * const fe
 			if (stmt->result_bind[i].bound == TRUE) {
 				zval *result = &stmt->result_bind[i].zv;
 				ZVAL_DEREF(result);
-				zval_dtor(result);
+				zval_ptr_dtor(result);
 				ZVAL_NULL(result);
 			}
 		}