d3dx8 {5/7] Implement D3DXMatrixStack_Pop

[H. Verbeet]

On 08/04/2008, David Adam <david.adam.cnrs at gmail.com> wrote:
> +    if ( This->current == 0 )
> +    {
> +     HeapFree(GetProcessHeap(), 0, This->matrix);
> +     return D3DERR_INVALIDCALL;
> +    }
> +    This->current = This->current -1;
If This->current was 0 when calling Pop, it now points at a
non-existing item. This would probably break things like LoadMatrix,
GetTop, etc. Also, calling Pop again would result in a double free of
This->matrix.