public void Undo()
{
if (curr_CS == null && prev_CS == null)
return;
if (prev_ADStack != (IntPtr)0)
CompressedStack.RestoreAppDomainStack(prev_ADStack);
CompressedStack.SetCompressedStackThread(prev_CS);
prev_CS = null;
curr_CS = null;
prev_ADStack = (IntPtr)0;
}
}