This is a modified example from the structs page in the d spec:

import std.stdio;

struct S { 
    int a;
    int b;
    int c;
    int d = 7;
}

void test(int i)
{
    S q = {2, i};
    writeln(q);
}

void main() { 
    test(4); 
}


This writes S(2, 4, 33686018, 33686018). 
These look like garbage values to me.