Nat!'s Web Journal

error: @defs is not supported in new abi

The offending code looks something like this

@interface Foo
{
   void   *table1_;
}
@endif

static inline BOOL   Foo_IsASpecialObject( Foo *self, id p)
{
   return( NSHashGet( ((struct { @defs( Foo) } *) self)->table1_, p) != nil);
}

These are all the solutions to this particular problem I came up with:

1. don't use the new ABI / abandon platform
2. pester ABI maintainer to support @defs
3. pester ABI maintainer to support static inline between @interface and @end
4. painstakingly create a shadow struct, that mimics the Foo class
5. unprotect inline accessed instance variables in Foo with @public

void   bar( va_list args)
{
   va_list   x;  
   
   x = args;
   return( va_arg( x, int));
}

error: array type 'va_list' (aka 'struct __va_list_tag [1]') is not assignable

I was curious if there was any "obvious" change in functionality. Here is the part of a function calling bar disassembled for three different architectures. The disassembly shows, that it's the same internally, two pointers are pushed unto the stack (put into parameter registers).

x86_64
	movq	%rbx, %rsi
	movl	%r12d, %edi
	call	_bar

i386:
	movl	-12(%ebp), %eax
	movl	%eax, 4(%esp)
	movl	8(%ebp), %eax
	movl	%eax, (%esp)
	call	_bar

ppc:
	lwz r4,76(r1)
	mr r3,r29
	bl _bar

void   bar( va_list args)
{
   va_list   *x;  
   
   x = &args;
   return( va_arg( *x, int));
}

#import <Foundation/Foundation.h>

@interface Foo : NSObject 
{
   long  a;
   long  b;
   long  c;
}

- (long) abc;

@end

@implementation Foo

- (long) abc
{
   return( self->a + self->b + self->c);
}

@end

The solution is in the full text.