diff --git a/sdc-plugin/buffers.h b/sdc-plugin/buffers.h
index 32a60b2..024416b 100644
--- a/sdc-plugin/buffers.h
+++ b/sdc-plugin/buffers.h
@@ -36,7 +36,7 @@
 };
 
 struct IBuf : Buffer {
-    IBuf() : Buffer(1, "IBUF", "O"){};
+    IBuf() : Buffer(0, "IBUF", "O"){};
 };
 
 struct Bufg : Buffer {
diff --git a/sdc-plugin/tests/counter/counter.golden.sdc b/sdc-plugin/tests/counter/counter.golden.sdc
index 3c9a20c..a70e95d 100644
--- a/sdc-plugin/tests/counter/counter.golden.sdc
+++ b/sdc-plugin/tests/counter/counter.golden.sdc
@@ -1,6 +1,6 @@
 create_clock -period 10 -waveform {0 5} clk_int_1
-create_clock -period 10 -waveform {1 6} ibuf_proxy_out
-create_clock -period 10 -waveform {2 7} \$auto\$clkbufmap.cc:247:execute\$1918
-create_clock -period 10 -waveform {1 6} \$auto\$clkbufmap.cc:247:execute\$1920
-create_clock -period 10 -waveform {3 8} middle_inst_1.clk_int
-create_clock -period 10 -waveform {2 7} middle_inst_4.clk
+create_clock -period 10 -waveform {0 5} ibuf_proxy_out
+create_clock -period 10 -waveform {0 5} \$auto\$clkbufmap.cc:247:execute\$1918
+create_clock -period 10 -waveform {0 5} \$auto\$clkbufmap.cc:247:execute\$1920
+create_clock -period 10 -waveform {1 6} middle_inst_1.clk_int
+create_clock -period 10 -waveform {1 6} middle_inst_4.clk
diff --git a/sdc-plugin/tests/pll/pll.golden.sdc b/sdc-plugin/tests/pll/pll.golden.sdc
index 4f9a132..c6ba07a 100644
--- a/sdc-plugin/tests/pll/pll.golden.sdc
+++ b/sdc-plugin/tests/pll/pll.golden.sdc
@@ -1,5 +1,5 @@
-create_clock -period 10 -waveform {1 6} \$auto\$clkbufmap.cc:247:execute\$1827
-create_clock -period 10 -waveform {2 7} \$techmap1716\FDCE_0.C
+create_clock -period 10 -waveform {0 5} \$auto\$clkbufmap.cc:247:execute\$1827
+create_clock -period 10 -waveform {1 6} \$techmap1716\FDCE_0.C
 create_clock -period 10 -waveform {0 5} \$auto\$clkbufmap.cc:247:execute\$1829
 create_clock -period 10 -waveform {1 6} main_clkout0
 create_clock -period 2.5 -waveform {0 1.25} \$auto\$clkbufmap.cc:247:execute\$1831