diff --git a/sim/group.lua b/sim/group.lua
index b4ac9a5..8154ec2 100644
--- a/sim/group.lua
+++ b/sim/group.lua
@@ -45,6 +45,7 @@ function Group.new()
 	net.state_num[0] = 0
 	net.in_queue[0] = 0
 	net.update_tick[0] = 0
+	net.gates_update_c = ffi.cast("struct Gate**", 0)
 	
 	net.c = ffi.new("struct Net")
 	net.c.state = net.state
@@ -52,7 +53,8 @@ function Group.new()
 	net.c.in_queue = net.in_queue
 	net.c.update_tick = net.update_tick
 	net.c.num_gates_update = net.num_gates_update
-	net.c.gates_update_c = ffi.cast("struct Gate**", 0)
+	net.c.gates_update_c = net.gates_update_c
+	
 	net.c.id = net.id
 	
 	return net
@@ -242,8 +244,9 @@ function Group.rebuild_ports(net)
 			end
 		end
 	end
-	net.gates_update_c = ffi.new("struct Gate*["..(net.num_gates_update[0]).."]")
+	net.gates_update_c = ffi.new("struct Gate*["..(net.num_gates_update[0]+1).."]")
 	for i = 0, net.num_gates_update[0]-1 do
 		net.gates_update_c[i] = net.gates_update[i+1].c
 	end
+	net.c.gates_update_c = net.gates_update_c
 end
diff --git a/sim/simulation.lua b/sim/simulation.lua
index d635246..6ba8a8f 100644
--- a/sim/simulation.lua
+++ b/sim/simulation.lua
@@ -293,7 +293,7 @@ end
 
 function Simulation.dequeuegroup(sim, group)
 	if group.in_queue[0]~=0 then
-		array_remove(sim.groupqueue, group.c, true)
+		array_remove(sim.groupqueue, group, true)
 		sim.num_groupqueue = sim.num_groupqueue - 1
 		group.in_queue[0] = 0
 	end