diff --git a/passes/opt/opt_clean.cc b/passes/opt/opt_clean.cc
index b3e3cd33a..3892c7581 100644
--- a/passes/opt/opt_clean.cc
+++ b/passes/opt/opt_clean.cc
@@ -283,7 +283,7 @@ bool compare_signals(RTLIL::SigBit &s1, RTLIL::SigBit &s2, SigPool &regs, SigPoo
 	if (attrs1 != attrs2)
 		return attrs2 > attrs1;
 
-	return strcmp(w2->name.c_str(), w1->name.c_str()) < 0;
+	return w2->name.lt_by_name(w1->name);
 }
 
 bool check_public_name(RTLIL::IdString id)