D statically allocated class instnace

example.d

void main()
{
    throw globalInstance!Error("This is an Error()", null);
}

T globalInstance(T, bool tls = true, Args...)(auto ref Args args)
if (is(T == class))
{
    // There really should be a trait for this:
    enum classAlignment = 2 * (void*).sizeof; // until then, here's a reasonable guess :)
    enum objSize = __traits(classInstanceSize, T);

    static if (tls)
        static align(classAlignment) void[objSize] _store;
    else
        static __gshared align(classAlignment) void[objSize] _store;

    static T get()
    {
        _store[0 .. __traits(classInstanceSize, T)] = typeid(T).initializer[];
        return cast(T) _store.ptr;
    }
    auto typedStore = (cast(T function() @trusted pure nothrow @nogc) &get)();

    import core.lifetime : emplace;
    return emplace!T(typedStore, args);
}