Prevent accidental mixing of GNU runtime headers with GNUstep runtime.h.

objc/runtime.h

@@ -3,9 +3,10 @@
 
 // If __LEGACY_GNU_MODE__ is defined then we include the old GNU runtime header
 // instead of this one
-#ifndef __OBJC_LEGACY_GNU_MODE__
 #define __GNUSTEP_RUNTIME__
 
+
+
 #include <stdint.h>
 #include <stddef.h>
 #include <sys/types.h>
@@ -36,6 +37,10 @@ typedef struct objc_ivar* Ivar;
 
 // Don't redefine these types if the old GNU header was included first.
 #ifndef __objc_INCLUDE_GNU
+// Define the macro so that including the old GNU header does nothing.
+#	define __objc_INCLUDE_GNU
+#	define __objc_api_INCLUDE_GNU
+
 typedef struct objc_selector *SEL;
 
 typedef struct objc_class *Class;
@@ -45,7 +50,8 @@ typedef struct objc_object
 	Class isa;
 } *id;
 
-struct objc_super {
+struct objc_super
+{
 	id receiver;
 #	if !defined(__cplusplus)  &&  !__OBJC2__
 	Class class;
@@ -117,6 +123,8 @@ struct objc_method_description
 #	define Nil ((Class)_OBJC_NULL_PTR)
 #endif
 
+#include "slot.h"
+
 BOOL class_addIvar(Class cls,
                    const char *name,
                    size_t size,
@@ -302,11 +310,6 @@ const char *sel_getType_np(SEL aSel);
  */
 unsigned sel_copyTypes(const char *selName, const char **types, unsigned count);
 
-#else
-#include "runtime-legacy.h"
-#endif // __LEGACY_GNU_MODE__
-#include "slot.h"
-
 /**
  * New ABI lookup function.  Receiver may be modified during lookup or proxy
  * forwarding and the sender may affect how lookup occurs.