If a struct field is default-initialized to `void` then this will override any later default initialization of a whole instance of that struct.

For example, in the following code:

//////////////////////////////
struct Inner
{
    uint alpha = void;
    uint beta = 66;
}

struct Outer
{
    Inner inner = Inner(23, 99);
}


void main ()
{
    import std.stdio : writeln;
    Outer outer;
    outer.inner.writeln;
}
//////////////////////////////

... the result with dmd is that `outer.inner` is `Inner(0, 99)` instead of the expected `Inner(23, 99)`.

Compiling with e.g. LDC produces the expected result of `Inner(23, 99)`.

Note, the issue still appears even if DMD is used with the same frontend version as LDC.  This therefore appears to be a DMD backend issue.