Not a good idea to throw exceptions in destructor in C++

When using try-catch blocks in C++, it is not a good to throw exceptions in destructor. Briefly, it may cause SIGABORT at runtime since the exception thrown in destructor may not be caught.

In MAC OS, you will get a “terminate called without an active exception” error. Then cause unexpected errors further on.

In Linux and Windows, the exception thrown in destructor will be caught by system. Then the program terminates

Look at the following C++ code

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// Author Name: Need-Being
// Modification date: 19/09/2011
// File description: Sample code to show error
 
#include <iostream>
#include <string>
using namespace std;
 
class myexcept : public exception
{
	public:
		myexcept(const string& str) { msg = str; }
		virtual ~myexcept() throw() {};
		virtual const char* what() const throw() {return msg.c_str();}
	private:
		string msg;
};
 
class badclass
{
	public:
		badclass(){};
		~badclass() { throw myexcept("huh...hurt!"); }
		void dosome() { throw myexcept("huh?"); }
};
 
int main()
{
	try
	{
		badclass bad;
		bad.dosome();
	}
	catch (const myexcept& e)
	{
		cerr << e.what() << endl;
	}
 
	return 0;
}

dosome() fucntion throws out an exception and is caught by my try-catch block. However, after having the statements in catch block done, the system starts to empty the memory allocated to the stack in the try block by calling destructors. This time, the exception thrown by the destructor cannot be caught by any try-catch blocks. Hence, the error appears.

Unfortunately, you will still fail to catch the exception thrown by the destructor, although you use nested try-catch blocks.