genlib/fifo: add missing import

diff --git a/migen/genlib/fifo.py b/migen/genlib/fifo.py
index 33c984b8bc96aaeefaea36d67acae2d9ad6424cf..f3e24d5afe9ef73dea377de26ec0bc15d1f77909 100644 (file)
--- a/migen/genlib/fifo.py
+++ b/migen/genlib/fifo.py
@@ -1,6 +1,7 @@
 from migen.fhdl.structure import *
 from migen.fhdl.module import Module
 from migen.fhdl.specials import Memory
+from migen.fhdl.bitcontainer import flen
 from migen.genlib.cdc import NoRetiming, MultiReg, GrayCounter
 from migen.genlib.record import layout_len, Record