Make == for associative arrays test for equality, not identity. _aaEq was added to runtime/internal/aaA.d which forwards to TypeInfo_AssociativeArray.equals in genobj.d. On the codegen side, DtoAAEquals was added to gen/aa.cpp and is called from EqualExp::toElem in gen/toir.cpp. I assume that the frontend will produce an error if == is used on associative arrays of different type. This fixes DMD bug 1429.

module tuple1;

template Tuple(T...) {
    alias T Tuple;
}

struct S
{
    int i;
    long l;
}

void main()
{
    S s = S(Tuple!(1,2L));
    assert(s.i == 1);
    assert(s.l == 2);
}