Fixed bug and add division test in the base field.

src/circuit_builder.rs

@@ -300,7 +300,7 @@ impl<F: Extendable<D>, const D: usize> CircuitBuilder<F, D> {
         let degree_bits = log2_strict(degree);
         let subgroup = F::two_adic_subgroup(degree_bits);
 
-        let constant_vecs = self.constant_polys();
+        let constant_vecs = self.constant_polys(&prefixed_gates);
         let constants_commitment =
             ListPolynomialCommitment::new(constant_vecs, self.config.fri_config.rate_bits, false);
 

src/gadgets/arithmetic.rs

@@ -373,6 +373,29 @@ mod tests {
     use crate::fri::FriConfig;
     use crate::witness::PartialWitness;
 
+    #[test]
+    fn test_div() {
+        type F = CrandallField;
+        type FF = QuarticCrandallField;
+        const D: usize = 4;
+
+        let config = CircuitConfig::large_config();
+
+        let mut builder = CircuitBuilder::<F, D>::new(config);
+
+        let x = F::rand();
+        let y = F::rand();
+        let z = x / y;
+        let xt = builder.constant(x);
+        let yt = builder.constant(y);
+        let zt = builder.constant(z);
+        let comp_zt = builder.div_unsafe(xt, yt);
+        builder.assert_equal(zt, comp_zt);
+
+        let data = builder.build();
+        let proof = data.prove(PartialWitness::new());
+    }
+
     #[test]
     fn test_div_extension() {
         type F = CrandallField;