message: [15-wires] assert important invariant in permutation
diff: @@ -121,6 +121,10 @@ impl<F: FftField + SquareRootField> ConstraintSystem<F> {
  rng: &mut ThreadRng,
  ) -> Result<DensePolynomial<F>, ProofError> {
  let n = self.domain.d1.size as usize;
  +
  + // only works if first element is 1
  + assert!(self.domain.d1.elements().next() == Some(F::one()));
  +
  // initialize accumulator at 1
  let mut z = vec![F::one(); n];
  