unique_ptr

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• When to use virtual destructors? 16 answers

Given following class structure, I'm not able execute this line of code without program to crash at the end of the function.

For:

unique_ptr<BufferedFieldEncoder> p = make_unique<GenericFieldEncoder>();

I get:

Process finished with exit code 132 (interrupted by signal 4: SIGILL)

but this line works fine (no crash):

unique_ptr<FieldEncoder> p = make_unique<GenericFieldEncoder>(); 

This is how my class structure looks like

class FieldEncoder {
public:
    virtual void encode(const string &data, const FieldEncoderMode &mode) = 0;
}; 

class BufferedFieldEncoder : public FieldEncoder {
protected:
    vector<uint8_t> m_buffer;
public:
    vector<uint8_t> &getBuffer() {
        return m_buffer;
    }
};

class GenericFieldEncoder : public BufferedFieldEncoder {
private:
    const unique_ptr<Something> something; (maybe this line is necessary)

public:
    explicit GenericFieldEncoder(); // initialisation of 'something'

    void encode(const string &data, const FieldEncoderMode &mode) override;
};

How can I create an instance of derived class and store it in unique_ptr of abstract derived class?

unique_ptr<BufferedFieldEncoder> p = make_unique<GenericFieldEncoder>();

I'm no c++ expert as you can see :)