Remove an old workaround that was kept around for ABI-compatibility on x86-64 between different LLVM versions. This means LLVM r67588 is required if you want to compile for x86-64, otherwise the backend will assert when you try to return e.g. struct { int i; char c; } from a function. (In particular, this is no longer compatible with LLVM 2.5) It also means that any code returning small structs on x86-64 will probably need to be recompiled in order to be linkable to code compiled with this change.

extern(C) int printf(char*, ...);

class A
{
    int i;
    void f()
    {
        printf("A.f\n");
    }
}

class B : A
{
    long l;
    void f()
    {
        printf("B.f\n");
    }
}

void main()
{
    A a = new B;
    a.f();
}