"Default initialization trap"

function_decl_trap.cpp

#include <iostream>

using namespace std;

template <typename T>
struct X {
    T x;
};

template <typename T>
void foo() {
    T a{};
    T b;
    T c(); // trap - function declaration

    cout << a.x << b.x << endl;
    cout  << c.x << endl; // a function doesn't have c.x
}
int main() {
    foo<X<int>>();
}