Re: compile error about destructor

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On Feb 23, 6:43 pm, George <Geo...@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
Thanks Abhishek,

1.

The __except handler is incorrect. There are only 3 valid values for
it. If the result of the expression for __except is anything other
than those 3 values probably it gets blocked searching for an
appropriate value (or whatever as per msdn, I am not sure what blocks
the execution) and hence the execution hangs up. You should rephrase
that as below:

Why only 3 values? What are the 3 values do you mean?

From MSDN, there are more values for exception code, check for the "Return
Value" section,

http://msdn2.microsoft.com/en-us/library/ms679356.aspx

I was not saying about the GetExceptionCode() function. It can return
variety of different codes. But the expression inside the except()
should evaluate to one of the following 3 values:

1) EXCEPTION_CONTINUE_SEARCH
2) EXCEPTION_CONTINUE_EXECUTION
3) EXCEPTION_EXECUTE_HANDLER

Depending upon the above values, the decision is made as to what needs
to be done after the __except expression evaluation. Should it go to
the handler (*_HANDLER), should it skip the handler and continue
execution from after it suppressing/ignoring the exception
(*_EXECUTION) or keep looking for the next handler (similar to
rethrowing the exception or better say, not handling it at all)
(*_SEARCH).

Read up on try-except here - http://msdn2.microsoft.com/en-us/library/s58ftw19(VS.80).aspx

2.

__try
{
   helper();
}
__except (GetExceptionCode() == EXCEPTION_ACCESS_VIOLATION ?
                       EXCEPTION_EXECUTE_HANDLER :
EXCEPTION_CONTINUE_EXECUTION)
{
   cout << "access violation caught 2" << endl;
}

What is your purpose of put EXCEPTION_EXECUTE_HANDLER and
EXCEPTION_CONTINUE_EXECUTION? I do not understand the whole function of the
statemet,

__except (GetExceptionCode() == EXCEPTION_ACCESS_VIOLATION ?
                       EXCEPTION_EXECUTE_HANDLER :
EXCEPTION_CONTINUE_EXECUTION)

Some more descriptions are appreciated. :-)

See above.
.

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