#include <iostream>
#include <type_traits>
 
 
struct base_pod_t {
    unsigned x;
};
 
struct der_pod_t : public base_pod_t { };
 
int main()
{
    std::cout << "base_pod_t is POD: " << std::is_pod<base_pod_t>::value << std::endl;
    std::cout << "der_pod_t  is POD: " << std::is_pod<der_pod_t>::value << std::endl;
    base_pod_t b1 = {};     // OK
    base_pod_t b2 = {3};    // OK
 
    der_pod_t p1 = {};      // OK
//    der_pod_t p2 = {4};   // ERROR!
}

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