Fix segment constructor

prover/src/matrix/segments.rs

@@ -61,12 +61,8 @@ impl<B: StarkField, const N: usize> Segment<B, N> {
         assert_eq!(poly_size, twiddles.len() * 2);
         assert!(poly_offset < polys.num_base_cols());
 
-        // determine the number of polynomials to add to this segment; this number can be either N,
-        // or smaller than N when there are fewer than N polynomials remaining to be processed
-        let num_polys_remaining = polys.num_base_cols() - poly_offset;
-
         // allocate memory for the segment
-        let data = if num_polys_remaining >= N {
+        let data = if polys.num_base_cols() - poly_offset >= N {
             // if we will fill the entire segment, we allocate uninitialized memory
             unsafe { uninit_vector::<[B; N]>(domain_size) }
         } else {