Re: [boost] [thread] RFC standard proposed mutex, read-write mutex, condition

From: David Abrahams (dave_at_[hidden])
Date: 2007-08-26 10:31:32

on Fri Aug 24 2007, Howard Hinnant <howard.hinnant-AT-gmail.com> wrote:

> The above appears to be a reasonable and valid use case to me for  
> "correcting" the condition/mutex binding.  The retooling operation is  
> a rare (exceptional) event.  Using exceptions for this makes the main  
> processing routine simpler/cleaner as it does not have to deal with  
> the complication of retooling.
>
> In summary, we have valid use cases for both not checking condition/ 
> mutex consistency, and for checking condition/mutex consistency, with  
> both use cases built on "correctness" concerns as opposed to  
> "performance" concerns.  Where this leads us next, I'm not yet sure...

This is exactly the sort of use case in which I'd want to have
complete control of detecting the need for an exception and throwing
it myself.  And, as described in http://tinyurl.com/2ph58t, if you
rely on the std's checking and exception here you end up with the same
exception representing a severe programming error in one part of the
program and an expected, recoverable condition in another.  At some
point up the call stack, you don't know which is which.  I would
always want a specific "retooling" exception for the non-error case.

And, I repeat, when the mutex mismatch *does* represent an error, I
*really* don't want a mandated throw.

-- 
Dave Abrahams
Boost Consulting
http://www.boost-consulting.com
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