[c++-pthreads] Restating the Jason model

[Dave Butenhof]

Alexander Terekhov wrote:

>Jason Merrill wrote:
>[...]
>  
>
>>>Well, yes; although it also seems better to make one new rule for the new
>>>"thread terminating exceptions" rather than two separate new rules.
>>>      
>>>
>>There's no way to use the same rules for both, since we can't re-assert
>>deferred exit.
>>    
>>
>Sure there's a way to use the same rules for both. Get rid of re-assert
>for cancellation.
>  
>
And it can work the other way, too. It's just as easy to re-assert exit 
as cancel; instead of calling pthread_cancel() on the current thread 
when the cancel exception is destroyed, you call pthread_exit() when the 
exit exception is destroyed. You'd need to retain the original exit 
status (void*) value, but there's no reason that can't be part of the 
exit exception object.

Now, whether you WANT TO or SHOULD re-assert either condition is clearly 
a contentious issue and not likely to be resolved any any consensus 
soon. But either is technically feasible if it's decided to be correct 
and desirable.

Just to restate, though; I DON'T think that re-asserting is "correct", 
but at this time I'm willing to grant that given common practice within 
the STL and presumably application code, it may be necessary all the same.

-- 
/--------------------[ David.Butenhof at hp.com ]--------------------\
| Hewlett-Packard Company       Tru64 UNIX & VMS Thread Architect |
|     My book: http://www.awl.com/cseng/titles/0-201-63392-2/     |
\----[ http://homepage.mac.com/dbutenhof/Threads/Threads.html ]---/