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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;
+}
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