Better fix for the memleaks (bug 19943) by Moriyoshi

Zend/zend_execute.c

@@ -466,10 +466,20 @@ static inline void zend_assign_to_variable(znode *result, znode *op1, znode *op2
 						}
 
 						T->EA.data.str_offset.str->value.str.val[T->EA.data.str_offset.offset] = final_value->value.str.val[0];
-						if (op2
-							&& op2->op_type != IS_VAR
-							&& final_value == &T(op2->u.var).tmp_var) {
-							STR_FREE(final_value->value.str.val);       
+						
+						if (op2) {
+							if (op2->op_type == IS_VAR) {
+								if (value == &T(op2->u.var).tmp_var) {
+									STR_FREE(value->value.str.val);
+								}
+							} else {
+								if (final_value == &T(op2->u.var).tmp_var) {
+									/* we can safely free final_value here
+									 * because separation is done only
+									 * in case op2->op_type == IS_VAR */
+									STR_FREE(final_value->value.str.val);
+								}
+							}
 						}
 						if (final_value == &tmp) {
 							zval_dtor(final_value);