diff --git a/kernel/rtlil.cc b/kernel/rtlil.cc
index 7bd5b0c91..bdf56250d 100644
--- a/kernel/rtlil.cc
+++ b/kernel/rtlil.cc
@@ -5560,8 +5560,6 @@ bool RTLIL::SigSpec::is_chunk() const
 
 bool RTLIL::SigSpec::is_mostly_const() const
 {
-	cover("kernel.rtlil.sigspec.is_mostly_const");
-
 	int constbits = 0;
 	for (auto &chunk : chunks())
 		if (chunk.width > 0 && chunk.wire == NULL)