Calling C functions from D that return structs

[SiegeLord]

I want a workabout for this bug: http://d.puremagic.com/issues/show_bug.cgi?id=3717

Basically, a C function that returns a structure and is compiled with a non-DMC compiler thrashes the stack when called from D. Here's the assembly code for a function that does it (sorry for the AT&T assembler syntax):

<_al_map_rgba>:
push   %ebp
mov    %esp,%ebp
mov    0x8(%ebp),%eax
movzbl 0xc(%ebp),%edx
mov    0x66d24020(,%edx,4),%edx
mov    %edx,(%eax)
movzbl 0x10(%ebp),%edx
mov    0x66d24020(,%edx,4),%edx
mov    %edx,0x4(%eax)
movzbl 0x14(%ebp),%edx
mov    0x66d24020(,%edx,4),%edx
mov    %edx,0x8(%eax)
movzbl 0x18(%ebp),%edx
mov    0x66d24020(,%edx,4),%edx
mov    %edx,0xc(%eax)
leave  
ret    $0x4
lea    0x0(%esi),%esi

It's signature is this:

ALLEGRO_COLOR al_map_rgba(ubyte r, ubyte g, ubyte b, ubyte a);

Where ALLEGRO_COLOR is a quad of bytes. What I want is some sort of inline assembly preamble (and/or postamble, as it were) that will make it possible for me to call that function correctly. The suggestion made by Walter in the bug report is unacceptable for my purposes.

What I have tried is this:

ALLEGRO_COLOR get()
{
	auto c = al_map_rgba(255,255,255,255);
	asm
	{
		sub ESP, 4;
	}
	return c;
}

But it did not work. Any help appreciated.

-SiegeLord