Re: [boost] Re: A new boost::thread implementation?

From: David Abrahams (dave_at_[hidden])
Date: 2003-02-10 13:09:25

"Peter Dimov" <pdimov_at_[hidden]> writes:

> Unspecified, but I don't think we can avoid that with the low-level
> interface. High level wrappers that package creation and execution would be
> immune to this problem.

Is there really a need for a low-level async_call interface?  After
all, the existing threads interface provides all the low-levelness
you can handle.

>>>> Actually, there's another minor issue as well.  The user can call
>>>> operator() and then let the async_call go out of scope with out ever
>>>> calling result().  Mayhem would ensue.  The two options for dealing
>>>> with this are to either block in the destructor until the call has
>>>> completed or to simply document this as undefined behavior.
>>>
>>> Yes, good point, I missed that.
>>
>> I lean towards simple undefined behavior.  How do you feel about it?
>
> Seems entirely reasonable. I don't think that we can "fix" this. Accessing
> an object after it has been destroyed is simply an error; although this is
> probably a good argument for making async_call copyable/counted so that the
> copy being executed can keep the representation alive.

Seems like this is also pointing at a high-level interface...

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com