> I'm pretty sure that the user presumes that |__ATARI__| is defined 
> here too. I can imagine that you argue that it doesn't makes sense as 
> the Atari 5200 isn't a superset of an 8-bit Atari computer. In that 
> case we maybe should start to think if the "classic" target 'atari' 
> should be renamed to something else in order to allow |__ATARI__|, 
> 'atari.inc' etc. to refer to all Atari machines...


I don't agree. "All Atari machines" would for example include the Lynx, 
and a potential Atari 7800 port where the 7800 has nothing in common 
with targets atari, atarix, atari5200, and lynx.
The 5200 really hasn't much in common with the Atari computers, except 
for the same custom chips (and these at different addresses).