Question

This is the code:

#include <iostream>
#include <exception>

using namespace std;

class excp1:exception
{
    public:
    virtual const char* what() const throw()
    {
        return "Bad ass exception";
    }
};


int main(int argc, char **argv)
{
    try
    {
        if(1!=0)
            throw new excp1();
    }
    catch(excp1& e)
    {
        cerr<<e.what();
    }
    return 0;
}

But it doesn’t print what I have put as return value of what (“Bad ass exception”), instead it prints:

Terminate called after throwing an instance of' excp1*'
Aborted

How to manage to print what I want?

Answer 1

You should throw the exception by value and catch it by reference.

You should have:

throw excp1();

Throwing a pointer type with dynamic memory allocation would leak the memory and cause undefined behavior.