void BufferPainter::FinishPathJob()
{
	if(jobcount == 0)
		return;

	CoWork co;
	co * [&] {
		for(;;) {
			int i = co.Next();
			if(i >= jobcount)
				break;
			INTERLOCKED {
			CoJob& b = cojob[i];
			b.rasterizer.Reset();
			PathJob j(b.rasterizer, b.width, b.path_info, b.attr, b.preclip, b.regular);
			if(!j.preclipped) {
				b.evenodd = j.evenodd;
				BufferPainter::RenderPathSegments(j.g, b.path_info->path[b.subpath], j.regular ? &b.attr : NULL, j.tolerance);
			}
			}
		}
	};

If problem disappears, try to move INTERLOCKED down line by line (until if) to see when/if it reappears.