/* GNU Objective C Runtime nil receiver function
- Copyright (C) 1993, 1995, 1996 Free Software Foundation, Inc.
+ Copyright (C) 1993, 1995, 1996, 2002, 2009, 2010
+ Free Software Foundation, Inc.
Contributed by Kresten Krab Thorup
-This file is part of GNU CC.
+This file is part of GCC.
-GNU CC is free software; you can redistribute it and/or modify it under the
+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 2, or (at your option) any later version.
+Foundation; either version 3, or (at your option) any later version.
-GNU CC is distributed in the hope that it will be useful, but WITHOUT ANY
+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.
-You should have received a copy of the GNU General Public License along with
-GNU CC; see the file COPYING. If not, write to the Free Software
-Foundation, 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA. */
+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/>. */
-/* As a special exception, if you link this library with files compiled with
- GCC to produce an executable, this does not cause the resulting executable
- to be covered by the GNU General Public License. This exception does not
- however invalidate any other reasons why the executable file might be
- covered by the GNU General Public License. */
/* This is the nil method, the function that is called when the receiver
of a method is nil */
-#include "runtime.h"
+#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__)), ...)
+nil_method (id receiver, SEL op __attribute__ ((__unused__)))
{
return receiver;
}
-
-
-
-
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