Add note to clone() / ZEND_CLONE that implementations need to be kept in sync

Author: TimWolla

Zend/zend_builtin_functions.c

@@ -77,6 +77,8 @@ ZEND_FUNCTION(clone)
 		Z_PARAM_OBJ(zobj)
 	ZEND_PARSE_PARAMETERS_END();
 
+	/* clone() also exists as the ZEND_CLONE OPcode and both implementations must be kept in sync. */
+
 	zend_class_entry *scope = zend_get_executed_scope();
 
 	zend_class_entry *ce = zobj->ce;

Zend/zend_vm_def.h

@@ -6006,6 +6006,8 @@ ZEND_VM_COLD_CONST_HANDLER(110, ZEND_CLONE, CONST|TMPVAR|UNUSED|THIS|CV, ANY)
 	SAVE_OPLINE();
 	obj = GET_OP1_OBJ_ZVAL_PTR_UNDEF(BP_VAR_R);
 
+	/* ZEND_CLONE also exists as the clone() function and both implementations must be kept in sync. */
+
 	do {
 		if (OP1_TYPE == IS_CONST ||
 		    (OP1_TYPE != IS_UNUSED && UNEXPECTED(Z_TYPE_P(obj) != IS_OBJECT))) {