Hum ... bad news ;-) ...
Thanks a lot for the reply
Selon "Young, Michael" <Michael.Young@xxxxxxxxxx>:
> I believe this is a C++ issue, not a G++ compiler issue.
> From the C++ standard (ISO 14882 15.1 P3) :
>
> "A throw-expression initializes a temporary object, the type of which is
> determined by removing any top-level cv-qualifiers from the static type
> of the operand of throw and adjusting the type from "array of T" or
> "function returning T" to "pointer to T" or "pointer to function returning
> T", respectively."
>
> Note that the type thrown is the *static* (not dynamic) type of the operand
> to the throw statement. In your example, this is the static type of excp
> (which is ErrorBase, per the parameter definition) in the throw_exception
> function.
>
> So, this is indeed "normal (standard compliant)" (if not your desired)
> behavior.
>
> Laurent Marzullo writes :
> >
> > Hello,
> >
> > Here a little program.
> >
> > #include <iostream>
> >
> > class ErrorBase {}
> > class Error : public ErrorBase {}
> >
> > void
> > throw_exception( const ErrorBase& excp )
> > {
> > throw excp;
> > }
> >
> >
> > void
> > function( void )
> > {
> > Error a;
> > throw_exception( a );
> > }
> >
> > int
> > main( void )
> > {
> > try
> > {
> > function();
> > }
> > catch ( const Error& err )
> > {
> > std::cerr << "Error\n";
> > }
> > catch ( const ErrorBase& err )
> > {
> > std::cerr << "ErrorBase\n";
> > }
> > catch ( ... )
> > {
> > std::cerr << "Unknown exception !\n";
> > }
> > }
> >
> >
> > This program call a function which throw an exception of type 'Error'
> (which
> > inherite from 'ErrorBase').
> >
> > But the catch bloc only catch ErrorBase exception and not Error ?
> > Is it a normal behavior ?
> > I know that there's a copy of the object when a throw occur but is it not a
> copy
> > of the real type of the object that must happen ?
> >
> > I want my function throw_exception to throw the real type of the object
> passed
> > as parameter. How may I achieve this ?
> >
> > May I dynamic_cast to all possible exception that must be passed to
> > throw_exception as:
> >
> > if ( dynamic_cast<const Error*>( &excp ) != 0 )
> > throw Error();
> > else
> > throw excp;
> >
> >
> > Any hint, help ??
> >
>
>
+--------------------+
+ Laurent Marzullo
+
