diff --git a/migen/fhdl/structure.py b/migen/fhdl/structure.py
index 3b4033f83..0ac9b5250 100644
--- a/migen/fhdl/structure.py
+++ b/migen/fhdl/structure.py
@@ -209,14 +209,14 @@ class Instance:
 	def __init__(self, of, outs=[], ins=[], parameters=[], clkport="", rstport="", name=""):
 		self.of = of
 		if name:
-			self.name = name
+			self.name_override = name
 		else:
-			self.name = of
+			self.name_override = of
 		def process_io(x):
 			if isinstance(x[1], Signal):
 				return x # override
 			elif isinstance(x[1], BV):
-				return (x[0], Signal(x[1], self.name + "_" + x[0]))
+				return (x[0], Signal(x[1], self.name_override + "_" + x[0]))
 			else:
 				raise TypeError
 		self.outs = dict(map(process_io, outs))
diff --git a/migen/fhdl/tools.py b/migen/fhdl/tools.py
index 6ba4372dd..60419f8a8 100644
--- a/migen/fhdl/tools.py
+++ b/migen/fhdl/tools.py
@@ -73,13 +73,16 @@ def group_by_targets(sl):
 			groups.append((targets, [statement]))
 	return groups
 
-def list_inst_outs(i):
+def list_inst_ios(i, ins, outs):
 	if isinstance(i, Fragment):
-		return list_inst_outs(i.instances)
+		return list_inst_ios(i.instances, ins, outs)
 	else:
 		l = []
 		for x in i:
-			l += list(map(lambda x: x[1], list(x.outs.items())))
+			if ins:
+				l += x.ins.values()
+			if outs:
+				l += x.outs.values()
 		return set(l)
 
 def is_variable(node):
diff --git a/migen/fhdl/verilog.py b/migen/fhdl/verilog.py
index 7f9ceb94e..5f343cfeb 100644
--- a/migen/fhdl/verilog.py
+++ b/migen/fhdl/verilog.py
@@ -98,7 +98,7 @@ def _list_comb_wires(f):
 def _printheader(f, ios, name, ns):
 	sigs = list_signals(f)
 	targets = list_targets(f)
-	instouts = list_inst_outs(f)
+	instouts = list_inst_ios(f, False, True)
 	wires = _list_comb_wires(f)
 	r = "module " + name + "(\n"
 	firstp = True
@@ -213,7 +213,7 @@ def convert(f, ios=set(), name="top", clk_signal=None, rst_signal=None, return_n
 	if rst_signal is None:
 		rst_signal = Signal(name_override="sys_rst")
 		ios.add(rst_signal)
-	ns = build_namespace(list_signals(f) | ios)
+	ns = build_namespace(list_signals(f) | list_inst_ios(f, True, True) | ios)
 
 	ios |= f.pads