🚀 go-pugleaf

I've just tried porting some code to MSVC4 (it compiles and works with 
SC7.1 and BC4.5).

In effect it appears that the Microsoft compiler _requires_ anything 
thrown as an exception to have an accessible copy constructor.  (I've 
tended to make copy constructors private to ensure catch-by-reference
and aviod slicing bugs.)

Looking through the DWP I can't see any reason to require a copy 
constructor, but there are references to copying temporaries.

Is MSVC4 correct?

code:
class MyBaseException {
public:  MyBaseException() {}
         virtual char* what() = 0;
private: MyBaseException(const MyBaseException&);
};

class MyException1 : public  MyBaseException {
public:     virtual char* what() { return "MyException1"; }
};

int main() {
    try     {
        throw MyException1();
// error C2700: 'class MyException1' : cannot be thrown (use -W4 for more info)

// warning C4671: 'MyException1' : the copy constructor is inaccessible
    } catch (MyBaseException& e) {
        cout << "OK - got here (" << __LINE__ << ") : have a " << e.what()
		<< endl;
    } catch (...) {
        cout << "ERROR - got here (" << __LINE__ << ")" << endl;
    }
    return 0;
}


--
Alan Griffiths               | Also editor of: The ISDF Newsletter
Senior Systems Consultant,   | (An Association of C and C++ Users publication)
CCN Group Limited.           | (ISDF editor  : isdf@octopull.demon.co.uk)
(agriffiths@ma.ccngroup.com) | (For ACCU see : http://bach.cis.temple.edu/accu)

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