RE: [boost] Re: boost::execution_monitor impl under windows

From: Alan.Griffiths_at_[hidden]
Date: 2003-09-26 09:09:05

> -----Original Message-----
> From: Alexander Terekhov [mailto:terekhov_at_[hidden]]
> Sent: 26 September 2003 00:05
> 
> Gennadiy Rozental wrote:
> [...]
> > 1. Does SEH is an async exception?
> 
> No. 

Compared to C++ exceptions there are fewer guarantees regarding which
effects have completed of a C++ statement in which a SEH exception occurs.
(To the extent that is may be impossible to predict which statements will
have completed.)

> > 4. How the technique described in Dave A. article helps to 
> resolve a problem
> > discussed in items 3?
> 
> Dave A. should better fix the C++ std instead of hacking with MS SEH.

Dave has done something practical about the co-existance of two conflicting
exception handling technologies.  That is more than most of us - and I for
one find his work very useful.  Dave is not responsible for the current
situatuation.  IMO If anyone should be fixing anything it should be MS.

> > 5. What would be an ideal behavior?
> 
> A) WG21 mandates 2-phase EH

What advantage does that bring?

> 
> -and-
> 
> B) MS translates SEH to C++ exceptions "by default" (in C++ appls).

That way lies madness!

SEH exceptions can arise in "nothrow" code - this can invalidate the
programmer's assumptions about the state of the program.  Should that
happen, the last thing that is useful is to treat it as a C++ exception -
implying that the program is in a stable state.

It is conceiveable that a model in which C++ exceptions are a specialisation
of SEH exceptions is viable, but not, as you suggest, the converse.
-- 
Alan Griffiths
http://www.octopull.demon.co.uk/ 
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