Destructor for Qtconcurrent::Exception?

[bp45738]

I am deriving an exception class from Qtconcurrent::Exception, and am receiving a compilation error

looser throw specifier for 'virtual SException::~SException()'
overriding 'virtual QtConcurrent::Exception::~Exception() throw()'

The class is as follows

class SException : public QtConcurrent::Exception
{
public:
	SException(const QString& message) : message_(message) {}
	void raise() const { throw *this; }
	Exception *clone() const { return new SException(*this); }
	QString message() const { return message_; }
 
private:
	QString message_;
};

class SException : public QtConcurrent::Exception
{
public:
	SException(const QString& message) : message_(message) {}
	void raise() const { throw *this; }
	Exception *clone() const { return new SException(*this); }
	QString message() const { return message_; }

private:
	QString message_;
};

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How do you specify the destructor correctly? I have already tried specifying a virtual destructor in the derived class but still get the same error.

[wysota]

Did you specify throw() for your destructor?

[bp45738]

When I add the destructor

virtual ~SException() throw();

virtual ~SException() throw();

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the compiler error goes away, but now I get a linking error looking for the implementation of the SException destructor.

What is the difference between

virtual ~SException() throw();

virtual ~SException() throw();

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and

virtual ~SException() { throw(); }

virtual ~SException() { throw(); }

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?

[wysota]

You get a linker error because you didn't implement a destructor that contains a throw declaration. If you declare a method with throw(), you need to implement a method with throw().

About your question -- the difference is like between a bucket of water and an apple.

[bp45738]

Thanks, I figured out what throw() does and I added an implementation to the destructor.