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/* GNU Objective C Runtime nil receiver function

   Copyright (C) 1993, 1995, 1996, 2002 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 2, 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.

You should have received a copy of the GNU General Public License along with

GCC; see the file COPYING.  If not, write to the Free Software

Foundation, 51 Franklin Street, Fifth Floor,

Boston, MA 02110-1301, USA.  */

/* 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 "objc/runtime.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;

}