diff --git a/migen/test/test_size.py b/migen/test/test_size.py
index 2c29116a2..54f9e99df 100644
--- a/migen/test/test_size.py
+++ b/migen/test/test_size.py
@@ -9,8 +9,8 @@ def _same_slices(a, b):
 
 class SignalSizeCase(unittest.TestCase):
     def setUp(self):
-        self.i = 0xaa
-        self.j = -127
+        self.i = C(0xaa)
+        self.j = C(-127)
         self.s = Signal((13, True))
 
     def test_flen(self):
@@ -20,34 +20,3 @@ class SignalSizeCase(unittest.TestCase):
 
     def test_flen_type(self):
         self.assertRaises(TypeError, flen, [])
-
-    def test_fiter(self):
-        for i, si in enumerate(fiter(self.s)):
-            self.assertTrue(_same_slices(si, self.s[i]))
-        self.assertEqual(list(fiter(self.i)),
-                [(self.i >> i) & 1 for i in range(8)])
-        self.assertEqual(list(fiter(self.j)),
-                [(self.j >> i) & 1 for i in range(8)])
-
-    def test_fiter_type(self):
-        self.assertRaises(TypeError, fiter, [])
-
-    def test_fslice(self):
-        sl = slice(1, None, 2)
-        fslice(self.s, sl)
-        self.assertEqual(fslice(self.i, sl), 15)
-        self.assertEqual(fslice(self.j, sl), 8)
-        self.assertEqual(fslice(-1, 9), 1)
-        self.assertEqual(fslice(-1, slice(0, 4)), 0b1)
-        self.assertEqual(fslice(-7, slice(0, None, 1)), 0b1001)
-
-    def test_fslice_type(self):
-        self.assertRaises(TypeError, fslice, [], 3)
-
-    def test_freversed(self):
-        freversed(self.s)
-        freversed(self.i)
-        freversed(self.j)
-
-    def test_freveseed_type(self):
-        self.assertRaises(TypeError, freversed, [])