diff --git a/xilinx/constids.inc b/xilinx/constids.inc
index 4f711905..b013aae8 100644
--- a/xilinx/constids.inc
+++ b/xilinx/constids.inc
@@ -491,7 +491,6 @@ X(IS_CE1_INVERTED)
 X(IS_CLKINSEL_INVERTED)
 X(IS_CLK_INVERTED)
 X(IS_CLR_INVERTED)
-X(IS_C_INVERTED)
 X(IS_DATAIN_INVERTED)
 X(IS_D_INVERTED)
 X(IS_IDATAIN_INVERTED)
diff --git a/xilinx/fasm.cc b/xilinx/fasm.cc
index 92ac7cc5..51100104 100644
--- a/xilinx/fasm.cc
+++ b/xilinx/fasm.cc
@@ -553,7 +553,7 @@ struct FasmBackend
 
                 pop();
                 if (negedge_ff) SET_CHECK(is_clkinv, true);
-                else SET_CHECK(is_clkinv, int_or_default(ff->params, id_IS_C_INVERTED) == 1);
+                else SET_CHECK(is_clkinv, int_or_default(ff->params, id_IS_CLK_INVERTED) == 1);
 
                 NetInfo *sr = ff->getPort(id_SR), *ce = ff->getPort(id_CE);
 
diff --git a/xilinx/pack.cc b/xilinx/pack.cc
index 08796ebb..17f2aff7 100644
--- a/xilinx/pack.cc
+++ b/xilinx/pack.cc
@@ -222,16 +222,16 @@ void XilinxPacker::pack_ffs()
     // ff_rules[id_FDSE].param_xform[id_IS_S_INVERTED] = id_IS_SR_INVERTED;
 
     ff_rules[id_FDCE_1] = XFormRule(ff_rules[id_FDCE]);
-    ff_rules[id_FDCE_1].set_params.emplace_back(id_IS_C_INVERTED, 1);
+    ff_rules[id_FDCE_1].set_params.emplace_back(id_IS_CLK_INVERTED, 1);
 
     ff_rules[id_FDPE_1] = XFormRule(ff_rules[id_FDPE]);
-    ff_rules[id_FDPE_1].set_params.emplace_back(id_IS_C_INVERTED, 1);
+    ff_rules[id_FDPE_1].set_params.emplace_back(id_IS_CLK_INVERTED, 1);
 
     ff_rules[id_FDRE_1] = XFormRule(ff_rules[id_FDRE]);
-    ff_rules[id_FDRE_1].set_params.emplace_back(id_IS_C_INVERTED, 1);
+    ff_rules[id_FDRE_1].set_params.emplace_back(id_IS_CLK_INVERTED, 1);
 
     ff_rules[id_FDSE_1] = XFormRule(ff_rules[id_FDSE]);
-    ff_rules[id_FDSE_1].set_params.emplace_back(id_IS_C_INVERTED, 1);
+    ff_rules[id_FDSE_1].set_params.emplace_back(id_IS_CLK_INVERTED, 1);
 
     generic_xform(ff_rules, true);
 }