c++ - How to test/verify that zero-initialization takes place -

i trying test 0 initialization on virtual machine g++ options -std=c++98, -std=c++03, -std=c++11

unfortunately there not many garbage values , see zeros in place shouldn't be.

how force random values can test this?

#include <iostream> #include <string>  using namespace std;  class { public:     int a; };   class b { public:   b(){}   int x; };  int main() {     {     int tab[50000] = {0};     }     a;     a* aa = new a;      b b;     b* bb = new b;      cout << a.a << endl;     cout << aa->a << endl;      cout << b.x << endl;     cout << bb->x << endl;     return 0; } 

you not guaranteed see random numbers. c/c++ standard says uninitialized values undefined, cannot values have. 0 ok (maybe virual machine zeros memory before allocating).

if need random numbers, generate them using <random>