Mercurial > hg > CbC > CbC_gcc
comparison libobjc/nil_method.c @ 111:04ced10e8804
gcc 7
author | kono |
---|---|
date | Fri, 27 Oct 2017 22:46:09 +0900 |
parents | |
children | 84e7813d76e9 |
comparison
equal
deleted
inserted
replaced
68:561a7518be6b | 111:04ced10e8804 |
---|---|
1 /* GNU Objective C Runtime nil receiver function | |
2 Copyright (C) 1993-2017 Free Software Foundation, Inc. | |
3 Contributed by Kresten Krab Thorup | |
4 | |
5 This file is part of GCC. | |
6 | |
7 GCC is free software; you can redistribute it and/or modify it under the | |
8 terms of the GNU General Public License as published by the Free Software | |
9 Foundation; either version 3, or (at your option) any later version. | |
10 | |
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS | |
13 FOR A PARTICULAR PURPOSE. See the GNU General Public License for more | |
14 details. | |
15 | |
16 Under Section 7 of GPL version 3, you are granted additional | |
17 permissions described in the GCC Runtime Library Exception, version | |
18 3.1, as published by the Free Software Foundation. | |
19 | |
20 You should have received a copy of the GNU General Public License and | |
21 a copy of the GCC Runtime Library Exception along with this program; | |
22 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see | |
23 <http://www.gnu.org/licenses/>. */ | |
24 | |
25 | |
26 /* This is the nil method, the function that is called when the receiver | |
27 of a method is nil */ | |
28 | |
29 #include "objc-private/common.h" | |
30 #include "objc/objc.h" | |
31 | |
32 /* When the receiver of a method invocation is nil, the runtime | |
33 returns nil_method() as the method implementation. This function | |
34 will be casted to whatever function was supposed to be executed to | |
35 execute that method (that function will take an id, followed by a | |
36 SEL, followed by who knows what arguments, depends on the method), | |
37 and executed. | |
38 | |
39 For this reason, nil_method() should be a function which can be | |
40 called in place of any function taking an 'id' argument followed by | |
41 a 'SEL' argument, followed by zero, or one, or any number of | |
42 arguments (both a fixed number, or a variable number !). | |
43 | |
44 There is no "proper" implementation of such a nil_method function | |
45 in C, however in all existing implementations it does not matter | |
46 when extra arguments are present, so we can simply create a function | |
47 taking a receiver and a selector, and all other arguments will be | |
48 ignored. :-) | |
49 */ | |
50 | |
51 id | |
52 nil_method (id receiver, SEL op __attribute__ ((__unused__))) | |
53 { | |
54 return receiver; | |
55 } |