diff --git a/techlibs/xilinx/synth_xilinx.cc b/techlibs/xilinx/synth_xilinx.cc
index 3d4a65c..f3cf9e0 100644
--- a/techlibs/xilinx/synth_xilinx.cc
+++ b/techlibs/xilinx/synth_xilinx.cc
@@ -557,6 +557,7 @@
 			else
 				techmap_args += " -map " + ff_map_file;
 			run("techmap " + techmap_args);
+			run("xilinx_dff");
 			run("clean");
 		}