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 structinit;

import structinit2;

struct S
{
    uint ui;
    float f;
    long l;
    real r;
}

S adef;

S a = { 1, 2.0f };
S b = { f:2.0f, l:42 };

Imp imp;

void main()
{
    //assert(a == S.init);
    //assert(b == S(0,3.14f,0,real.init));
}