1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
/* GNU Objective C Runtime nil receiver function
Copyright (C) 1993-2015 Free Software Foundation, Inc.
Contributed by Kresten Krab Thorup
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under the
terms of the GNU General Public License as published by the Free Software
Foundation; either version 3, or (at your option) any later version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
/* This is the nil method, the function that is called when the receiver
of a method is nil */
#include "objc-private/common.h"
#include "objc/objc.h"
/* When the receiver of a method invocation is nil, the runtime
returns nil_method() as the method implementation. This function
will be casted to whatever function was supposed to be executed to
execute that method (that function will take an id, followed by a
SEL, followed by who knows what arguments, depends on the method),
and executed.
For this reason, nil_method() should be a function which can be
called in place of any function taking an 'id' argument followed by
a 'SEL' argument, followed by zero, or one, or any number of
arguments (both a fixed number, or a variable number !).
There is no "proper" implementation of such a nil_method function
in C, however in all existing implementations it does not matter
when extra arguments are present, so we can simply create a function
taking a receiver and a selector, and all other arguments will be
ignored. :-)
*/
id
nil_method (id receiver, SEL op __attribute__ ((__unused__)))
{
return receiver;
}
|
