🚀 go-pugleaf

In article <4emq9l$2fn@hammy.lonestar.org> gordon@hammy.lonestar.org
(Gordon Burditt) writes: 
<snip>
   ANSI C Classic 2.1.2.2.3 Program Termination
   A RETURN FROM THE INITIAL CALL TO THE MAIN FUNCTION IS EQUIVALENT
   TO CALLING THE EXIT FUNCTION with the value returned by the main
   function as its argument.
   ...
   I claim that longjmp()ing out of an atexit function into main
   causes undefined behavior because main() has already returned
   (or, equivalently, called exit()) between the setjmp and
   longjmp calls.

   In fact, calling exit() may not unwind the stack like returning
   from main() does, so you might get away with it, but there's
   no guarantee.

Isn't the TC going to clarify that return from main is not exactly the
same as calling exit? Or is it just planning to restrict the
clarification to the situation with respect to the local variables?

In any case, without a change in the standard, I would consider that
the wording in the standard is that `a return ... is equivalent to
calling the exit function...' not the other way round. So, I would
interpret this as saying that return from main cannot unwind stack
either, exactly as exit cannot: not that both can.

Cheers
Tanmoy
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