Braced (uniform) Initialization

struct A
{
    // user provided constructor _missing_ initialization of `j`
    A()
    : i{3}
    {
    }
 
    int i;
    int j;
};
 
struct B
{
    // uses the default constructor
    int i;
    int j;
};
 
int main()
{
    A a;
    A a2{};  // only i gets initialized.
 
    B b;
    B b2{};  // both i and j get initialized.
}

Here is the transformed code:

struct A
{
  inline A()
  : i{3}
  {
  }
  
  int i;
  int j;
};
 
 
struct B
{
  int i;
  int j;
  // inline B() noexcept = default;
};
 
 
int main()
{
  A a = A();
  A a2 = A{};
  B b;
  B b2 = {0, 0};
  return 0;
}

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