diff --git a/halo2_proofs/src/plonk/circuit.rs b/halo2_proofs/src/plonk/circuit.rs
index 2c800082a9..93897e8697 100644
--- a/halo2_proofs/src/plonk/circuit.rs
+++ b/halo2_proofs/src/plonk/circuit.rs
@@ -2070,7 +2070,7 @@ impl<F: Field> ConstraintSystem<F> {
 
         // Substitute selectors for the real fixed columns in all gates
         for expr in self.gates.iter_mut().flat_map(|gate| gate.polys.iter_mut()) {
-            replace_selectors(expr, &selector_replacements, false);
+            replace_selectors(expr, selector_replacements, false);
         }
 
         // Substitute non-simple selectors for the real fixed columns in all
@@ -2081,7 +2081,7 @@ impl<F: Field> ConstraintSystem<F> {
                 .iter_mut()
                 .chain(lookup.table_expressions.iter_mut())
         }) {
-            replace_selectors(expr, &selector_replacements, true);
+            replace_selectors(expr, selector_replacements, true);
         }
 
         for expr in self.shuffles.iter_mut().flat_map(|shuffle| {
@@ -2090,7 +2090,7 @@ impl<F: Field> ConstraintSystem<F> {
                 .iter_mut()
                 .chain(shuffle.shuffle_expressions.iter_mut())
         }) {
-            replace_selectors(expr, &selector_replacements, true);
+            replace_selectors(expr, selector_replacements, true);
         }
     }
 
diff --git a/halo2_proofs/src/plonk/keygen.rs b/halo2_proofs/src/plonk/keygen.rs
index 3cf35b1ea1..cd03f05fdb 100644
--- a/halo2_proofs/src/plonk/keygen.rs
+++ b/halo2_proofs/src/plonk/keygen.rs
@@ -243,7 +243,6 @@ where
     )?;
 
     let mut fixed = batch_invert_assigned(assembly.fixed);
-    let max_degree = if compress_selectors { cs.degree() } else { 0 };
     let (cs, selector_polys) = if compress_selectors {
         cs.compress_selectors(assembly.selectors.clone())
     } else {
@@ -317,11 +316,6 @@ where
     )?;
 
     let mut fixed = batch_invert_assigned(assembly.fixed);
-    let max_degree = if vk.compress_selectors {
-        cs.degree()
-    } else {
-        0
-    };
     let (cs, selector_polys) = if vk.compress_selectors {
         cs.compress_selectors(assembly.selectors)
     } else {