Re: return from catch - UB?

From:
Alan Johnson <alanwj@no.spam.stanford.edu>
Newsgroups:
comp.lang.c++
Date:
Thu, 08 Jun 2006 16:37:42 -0700
Message-ID:
<e6acc7$d9k$1@news.Stanford.EDU>
Noah Roberts wrote:

The following code does VERY strange things in the debugger. Is there
anything wrong with the following code, UB or anything else?

#include <iostream>
#include <exception>
#include <stdexcept>

int main()
{
    int * parser;

    try
    {
        parser = 0;
    }
    catch (std::out_of_range & err)
    {
    }
    catch (std::bad_alloc & err)
    {
        return 0; // debugger jumps to here after hitting final brace -
"runs" this statement as many times as there are returns in catches.
    }
    catch (std::domain_error & err)
    {
        return -1;
    }
    catch (std::exception & err)
    {
        std::cerr << err.what() << std::endl;
    }
    catch(...)
    {
        return -1;
    } // debugger jumps to here after running code in try..

    return 0; // debugger finally jumps to here and leaves...other code in
this area will run but has been removed for brevity.
}

Granted, it isn't a normal thing to do, but AFAICT the standard
explicitly allows it.


Have you tried turning off all optimizations? This sounds exactly like
the sort of weird behavior you'd expect to see when trying to debug
optimized code.

--
Alan Johnson

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