diff --git a/passes/opt/opt_clean.cc b/passes/opt/opt_clean.cc
index 3892c7581..76f425099 100644
--- a/passes/opt/opt_clean.cc
+++ b/passes/opt/opt_clean.cc
@@ -467,8 +467,6 @@ bool rmunused_module_signals(RTLIL::Module *module, bool purge_mode, bool verbos
 					wire->attributes.erase(ID::init);
 				else
 					wire->attributes.at(ID::init) = initval;
-				used_signals.add(new_conn.first);
-				used_signals.add(new_conn.second);
 				module->connect(new_conn);
 			}
 
diff --git a/tests/opt/opt_clean_standalone_wires.ys b/tests/opt/opt_clean_standalone_wires.ys
new file mode 100644
index 000000000..d6716d725
--- /dev/null
+++ b/tests/opt/opt_clean_standalone_wires.ys
@@ -0,0 +1,10 @@
+read_rtlil << EOT
+module \test
+  wire \wire_a
+  wire \wire_f
+  connect \wire_f \wire_a
+end
+EOT
+
+opt_clean
+select -assert-count 0 */*