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diff --git a/libobjc/objc/message.h b/libobjc/objc/message.h
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+/* GNU Objective C Runtime messaging declarations
+   Copyright (C) 1993, 1995, 1996, 2004, 2009, 
+   2010 Free Software Foundation, Inc.
+
+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/>.  */
+
+#ifndef __objc_message_INCLUDE_GNU
+#define __objc_message_INCLUDE_GNU
+
+#include "objc.h"
+#include "objc-decls.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* This file includes declarations of the messaging functions and
+   types.  */
+
+/* Compatibility note: the messaging function is one area where the
+   GNU runtime and the Apple/NeXT runtime differ significantly.  If
+   you can, it is recommended that you use higher-level facilities
+   (provided by a Foundation library such as GNUstep Base) to perform
+   forwarding or other advanced messaging tricks.  */
+
+/* This function returns the IMP (C function implementing a method) to
+   use to invoke the method with selector 'op' of receiver 'receiver'.
+
+   This is the function used by the compiler when compiling method
+   invocations with the GNU runtime.  For example, the method call
+
+     result = [receiver method];
+
+   is compiled by the compiler (with the GNU runtime) into the
+   equivalent of:
+
+   {
+     IMP function = objc_msg_lookup (receiver, @selector (method));
+     result = function (receiver, @selector (method));
+   }
+
+   so, a call to objc_msg_lookup() determines the IMP (the C function
+   implementing the method) to call.  Then, the function is called.
+   If the method takes or returns different arguments, the compiler
+   will cast 'function' to the right type before invoking it, making
+   sure arguments and return value are handled correctly.
+
+   objc_msg_lookup() must always return a valid function that can be
+   called with the required method signature (otherwise the
+   compiler-generated code shown above could segfault).  If 'receiver'
+   is NULL, objc_msg_lookup() returns a C function that does nothing,
+   ignores all its arguments, and returns NULL (see nil_method.c).  If
+   'receiver' does not respond to the selector 'op', objc_msg_lookup()
+   will try to call +resolveClassMethod: or resolveInstanceMethod: as
+   appropriate, and if they return YES, it will try the lookup again
+   (+resolveClassMethod: and +resolveInstanceMethod: can thus install
+   dynamically methods as they are requested).  If
+   +resolveClassMethod: or +resolveInstanceMethod: are either not
+   available, or return NO, or return YES but 'receiver' still doesn't
+   implement the 'selector' after calling them, the runtime returns a
+   generic "forwarding" function that can be called with the required
+   method signature and which can process the method invocation
+   according to the forwarding API.  There are two runtime hooks that
+   allow Foundation libraries (such as GNUstep-Base) to return their
+   own forwarding function in preference to the runtime ones.  When
+   that happens, the Foundation library effectively takes complete
+   control of the forwarding process; any method invocation where the
+   selector is not implemented by the receiver will end up calling a
+   forwarding function chosen by the Foundation library.  */
+objc_EXPORT IMP objc_msg_lookup (id receiver, SEL op);
+
+/* Structure used when a message is send to a class's super class.
+   The compiler generates one of these structures and passes it to
+   objc_msg_lookup_super() when a [super method] call is compiled.  */
+
+/* In the traditional API, the super class field is called 'class' in
+   Objective-C and 'super_class' in Objective-C++.  In the new API
+   (objc/runtime.h) it is always called 'super_class'.  We detect the
+   "traditional API" by the fact that the objc/objc-api.h header
+   include guards are defined, which means objc/objc-api.h has been
+   included.  This works because objc/message.h does not exist in the
+   Traditional API and is only read because objc-api.h itself includes
+   it.  */
+#ifdef __objc_api_INCLUDE_GNU
+/* Traditional API.  */
+typedef struct objc_super
+{
+  id    self;       /* Id of the object sending the message. */
+#ifdef __cplusplus
+  Class super_class;
+#else
+  Class class;        /* Object's super class. */
+#endif
+} Super, *Super_t;
+#else
+/* Modern API.  */
+struct objc_super
+{
+  id    self;        /* The receiver of the message.  */
+  Class super_class; /* The superclass of the receiver.  */
+};
+#endif
+
+/* This is used by the compiler instead of objc_msg_lookup () when
+   compiling a call to 'super', such as [super method].  This requires
+   sending a message to super->self, but looking up the method as if
+   super->self was in class super->super_class.  */
+objc_EXPORT IMP objc_msg_lookup_super (struct objc_super *super, SEL sel);
+
+/* Hooks for method forwarding.  They make it easy to substitute the
+   built-in forwarding with one based on a library, such as ffi, that
+   implement closures, thereby avoiding gcc's __builtin_apply
+   problems.  __objc_msg_forward2's result will be preferred over that
+   of __objc_msg_forward if both are set and return non-NULL.  */   
+objc_EXPORT IMP (*__objc_msg_forward)(SEL);
+objc_EXPORT IMP (*__objc_msg_forward2)(id, SEL);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* not __objc_message_INCLUDE_GNU */