This program (see below) works in d0chb if used with the exception option 
(this option is disabled by default):

d0chb:/home/gris/mytest> setup D0RunII          // Setup KCC
d0chb:/home/gris/mytest> kcc-ar2 -x eg_errh.cpp
d0chb:/home/gris/mytest> a.out

Bien

Ok
d0chb:/home/gris/mytest>

In mausi (gcc version egcs-2.91.57) the program does not work, exception
handling is on by default but it does not catch the throw from the class:

mausi:/home/gris/cpp/tiny> gpp -fhandle-exceptions eg_errh.cpp
cc1plus: warning: -fhandle-exceptions has been renamed to -fexceptions (and is now on by default)
mausi:/home/gris/cpp/tiny> a.out
Abort
mausi:/home/gris/cpp/tiny> gpp -fexceptions eg_errh.cpp
mausi:/home/gris/cpp/tiny> a.out
Abort
mausi:/home/gris/cpp/tiny> 

The program aborts because it does not catch the throw.

In groucho it works (gcc version 2.7.2) with the -fhandle-exceptions option.

/////////////////////////////////////////////////////
// eg_errh.cpp : A simple exception handling example.

#include <iostream.h>

class ClassB { }; // This first!

class MyClass {
  int i;
public:
  MyClass(int j = 0) { i = j; };
  void seti(int f) { if (f > 10) throw ClassB(); i = f; };
};

int main()
{
  MyClass mc;

  try{
    mc.seti(11);
    cout << endl << "MAL" << endl;
  }

  catch (ClassB b) { cout << endl << "Bien" << endl; }

  catch (...){ }

  cout << endl << "Ok" << endl;
  
  return 0;
}


There seems to be a bug with gcc version egcs-2.91.57, if in the
program seti() is change to:

void seti(int f) { if (f > 10) throw ClassB(); i = f; cout << "Hola"; };

then it works!!