diff --git a/examples/basic/psync.py b/examples/basic/psync.py
index 444c62743..59422d5ef 100644
--- a/examples/basic/psync.py
+++ b/examples/basic/psync.py
@@ -12,7 +12,7 @@ class XilinxMultiRegImpl(MultiRegImpl):
 class XilinxMultiReg:
 	@staticmethod
 	def lower(dr):
-		return XilinxMultiRegImpl(dr.i, dr.idomain, dr.o, dr.odomain, dr.n)
+		return XilinxMultiRegImpl(dr.i, dr.o, dr.odomain, dr.n)
 
 ps = PulseSynchronizer("from", "to")
 v = verilog.convert(ps, {ps.i, ps.o}, special_overrides={MultiReg: XilinxMultiReg})
diff --git a/examples/basic/simple_gpio.py b/examples/basic/simple_gpio.py
index 4dc4f5fb8..0576473c7 100644
--- a/examples/basic/simple_gpio.py
+++ b/examples/basic/simple_gpio.py
@@ -17,7 +17,7 @@ class Example(Module):
 		###
 
 		gpio_in_s = Signal(ninputs)
-		self.specials += MultiReg(self.gpio_in, "ext", gpio_in_s, "sys")
+		self.specials += MultiReg(self.gpio_in, gpio_in_s, "sys")
 		self.comb += [
 			r_i.field.w.eq(gpio_in_s),
 			self.gpio_out.eq(r_o.field.r)
diff --git a/migen/genlib/cdc.py b/migen/genlib/cdc.py
index d28b98408..632b337eb 100644
--- a/migen/genlib/cdc.py
+++ b/migen/genlib/cdc.py
@@ -3,9 +3,8 @@ from migen.fhdl.specials import Special
 from migen.fhdl.tools import value_bits_sign, list_signals
 
 class MultiRegImpl:
-	def __init__(self, i, idomain, o, odomain, n):
+	def __init__(self, i, o, odomain, n):
 		self.i = i
-		self.idomain = idomain
 		self.o = o
 		self.odomain = odomain
 
@@ -24,10 +23,9 @@ class MultiRegImpl:
 		return Fragment(comb, {self.odomain: o_sync})
 
 class MultiReg(Special):
-	def __init__(self, i, idomain, o, odomain, n=2):
+	def __init__(self, i, o, odomain, n=2):
 		Special.__init__(self)
 		self.i = i
-		self.idomain = idomain
 		self.o = o
 		self.odomain = odomain
 		self.n = n
@@ -42,7 +40,7 @@ class MultiReg(Special):
 
 	@staticmethod
 	def lower(dr):
-		return MultiRegImpl(dr.i, dr.idomain, dr.o, dr.odomain, dr.n)
+		return MultiRegImpl(dr.i, dr.o, dr.odomain, dr.n)
 
 class PulseSynchronizer:
 	def __init__(self, idomain, odomain):
@@ -66,4 +64,4 @@ class PulseSynchronizer:
 		]
 		return Fragment(comb, 
 			{self.idomain: sync_i, self.odomain: sync_o},
-			specials={MultiReg(toggle_i, self.idomain, toggle_o, self.odomain)})
+			specials={MultiReg(toggle_i, toggle_o, self.odomain)})