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.

module structs3;

struct S
{
    char c;
    float f;
}

struct T
{
    S s;
    long l;
}

void main()
{
    T t;
    float f = void;
    float* fp = void;
    {f = t.s.f;}
    {t.s.f = 0.0;}
    {fp = &t.s.f;}
    {*fp = 1.0;}
    {assert(t.s.f == 1.0);}
    {assert(*(&t.s.f) == 1.0);}
    {t.s.c = 'a';}
    {assert(t.s.c == 'a');}
    {t.l = 64;}
    {assert(t.l == 64);}
}