Dummy helper struct that helps to debug when C++ objects get created, copied and destroyed.

dummy.h

#pragma once

/*
    Dummy struct that prints a line whenever it is constructed, copied, moved or destructed.
*/
struct dummy {
    int val;
    dummy() : val(0) { printf("dummy() def ctor\n"); }
    dummy(int v) : val(v) { printf("dummy(%d) ctor\n", val); }
    dummy(const dummy &d) : val(d.val) { printf("dummy(%d) copy ctor\n", val); }
    dummy(dummy &&d) : val(d.val) { printf("dummy(%d) move ctor\n", val); d.val = 0; }
    ~dummy() { printf("~dummy(%d) dtor\n", val); val = -1; }
};