Question

I have a requirement in my testing as when I am calling a function I am initializing the structure with 0. But, the moment function ex() gets called, ab the object of struct abc caontains garbage.
But I need to the structure abc should get initialized with 0.

Because I don’t have access to function ex(). So, whatever things I need to set, I need to set from main().

struct abc{
    int a[4];
};
void ex()
{
abc ab;
    printf("%d\n", ab.a);//Garbage value
}
int main()
{
    abc ab;
    memset(&ab, 0, sizeof(abc));
    printf("%d\n", ab.a);
return 0;
}

Please help.

Answer 1

You can give abc a default constructor that initializes the elements of the array to 0. This gets rid of the garbage values:

struct abc {
    int a[4];
    abc() : a() {}
};

Next, if you want myex to print the data of the abc created in main, you should give it an abc reference parameter. This is a C++11 version of myex:

#include <iostream>

void myex(const abc& item)
{
  for (const auto& n : item.a)
  {
    std::cout << n << " ";
  }
  std::cout << "\n";
}

int main()
{
  abc myabc;
  myex(myabc);
}