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			56 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			56 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
| /* GNU Objective C Runtime nil receiver function
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|    Copyright (C) 1993-2017 Free Software Foundation, Inc.
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|    Contributed by Kresten Krab Thorup
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| 
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| This file is part of GCC.
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| 
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| GCC is free software; you can redistribute it and/or modify it under the
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| terms of the GNU General Public License as published by the Free Software
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| Foundation; either version 3, or (at your option) any later version.
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| 
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| GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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| WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
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| FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
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| details.
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| 
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| Under Section 7 of GPL version 3, you are granted additional
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| permissions described in the GCC Runtime Library Exception, version
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| 3.1, as published by the Free Software Foundation.
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| 
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| You should have received a copy of the GNU General Public License and
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| a copy of the GCC Runtime Library Exception along with this program;
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| see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
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| <http://www.gnu.org/licenses/>.  */
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| 
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| 
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| /* This is the nil method, the function that is called when the receiver
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|    of a method is nil */
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| 
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| #include "objc-private/common.h"
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| #include "objc/objc.h"
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| 
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| /* When the receiver of a method invocation is nil, the runtime
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|    returns nil_method() as the method implementation.  This function
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|    will be casted to whatever function was supposed to be executed to
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|    execute that method (that function will take an id, followed by a
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|    SEL, followed by who knows what arguments, depends on the method),
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|    and executed.
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|    
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|    For this reason, nil_method() should be a function which can be
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|    called in place of any function taking an 'id' argument followed by
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|    a 'SEL' argument, followed by zero, or one, or any number of
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|    arguments (both a fixed number, or a variable number !).
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|    
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|    There is no "proper" implementation of such a nil_method function
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|    in C, however in all existing implementations it does not matter
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|    when extra arguments are present, so we can simply create a function
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|    taking a receiver and a selector, and all other arguments will be
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|    ignored. :-)
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| */
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| 
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| id
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| nil_method (id receiver, SEL op __attribute__ ((__unused__)))
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| {
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|   return receiver;
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| }
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