Error with class destructor

Question

Good morning, I am trying to develop a matrix math engine, the error that is giving in my code is this:

R4DVector3n.cpp:(.text+0x226): undefined reference to `R4DEngine::R4DMatrix3n::~R4DMatrix3n()'

This is my code:

#include <iostream>

using namespace std;
namespace R4DEngine
{
  class R4DMatrix3n
  {

  private:
  public:
    //Matrix data elements
    float matrixData[9] = {0.0};

    //constructors
    R4DMatrix3n();

    R4DMatrix3n(float m0, float m3, float m6, float m1, float m4, float m7, float m2, float m5, float m8);

    //copy constructors
    R4DMatrix3n &operator=(const R4DMatrix3n &value);

    //destructors
    ~R4DMatrix3n();

    void show()
    {

      // 3x3 matrix - column major. X vector is 0, 1, 2, etc. (openGL prefer way)
      //    0    3    6
      //    1    4    7
      //    2    5    8

      std::cout << "[" << matrixData[0] << "," << matrixData[3] << "," << matrixData[6] << "," << std::endl;
      std::cout << matrixData[1] << "," << matrixData[4] << "," << matrixData[7] << "," << std::endl;
      std::cout << matrixData[2] << "," << matrixData[5] << "," << matrixData[8] << "]" << std::endl;
    }
  };
  R4DMatrix3n::R4DMatrix3n()
  {

    // 3x3 matrix - column major. X vector is 0, 1, 2, etc. (openGL prefer way)
    //    0    3    6
    //    1    4    7
    //    2    5    8

    for (int i = 0; i < 9; i++)
    {
      matrixData[i] = 0.0f;
    }

    matrixData[0] = matrixData[4] = matrixData[8] = 1.0f;
  };

  R4DMatrix3n::R4DMatrix3n(float m0, float m3, float m6, float m1, float m4, float m7, float m2, float m5, float m8)
  {

    // 3x3 matrix - column major. X vector is 0, 1, 2, etc. (openGL prefer way)
    //    0    3    6
    //    1    4    7
    //    2    5    8

    matrixData[0] = m0;
    matrixData[3] = m3;
    matrixData[6] = m6;

    matrixData[1] = m1;
    matrixData[4] = m4;
    matrixData[7] = m7;

    matrixData[2] = m2;
    matrixData[5] = m5;
    matrixData[8] = m8;
  };
}

And the main code is this:

#include <iostream>
#include "R4DMatrix3n.h"

int main(int argc, const char * argv[]) {

    //create an instance of R4DMatrix3n
    R4DEngine::R4DMatrix3n m(2,3,1,5,3,1,4,3,1);

    //Print the values of the matrix
    m.show();

    return 0;
}

How could I solve?

Answer 1

Your code lacks destructor implementation. Substitute:

    ~R4DMatrix3n();

For:

    ~R4DMatrix3n() = default;

If you have a more complicated destructor, replace the default with the implementation.