Re: libtool, llvm-gcc, failing C++ exceptions

[Bob Friesenhahn]

On Sun, 10 Jan 2010, Ralf Wildenhues wrote:
> > My main comment is that it would be useful if the thrown class is
> > derived from std:exception (or one of its standard derived classes)
> > in order to flush out any issues which may stem from possible
> > partial template instantiation in libstdc++ (or pre-compiled
> > headers) as well as in the test translation unit.
>
> OK, sounds useful.  Would that entail more than just something like
> this incremental addition?

I think that the virtual what() method needs to be provided or else 
you have only a partially implemented class:

class MyException : public std::exception
{
  public;
    MyException() {}

  virtual const char *what() const throw()
  {
     return "My message";
  }
};

But this is a better class to test with since it uses more standard 
library stuff and is therefore more likely to fail if something is 
wrong:

#include <exception>
#include <string>
class MyException : public std::exception
{
  public;
    MyException(std::string str)
     : message(str)
    {
    }

  virtual const char *what() const throw()
  {
     return message.c_str();
  }

  private:
    std::string message;
};

Which can be thrown with

  throw MyException("My message");

Bob
--
Bob Friesenhahn
address@hidden, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/