fixes regression from arkworks-rs/std#29

Cargo.toml

@@ -20,8 +20,6 @@ zcash_proofs = { git = "https://github.com/zcash/librustzcash", version = "0.4"
 neptune = { git = "https://github.com/w3f/neptune", branch = "librustzcash-bis" }
 typenum = "1.11.2"
 
-bench-utils = { git = "https://github.com/scipr-lab/zexe", features = ["print-trace"]}
-
 [patch.crates-io]
 bellman = { git = "https://github.com/w3f/bellman.git", branch="neptune-bis" }
 
@@ -67,6 +65,7 @@ features = ["zeroize_derive"]
 [dev-dependencies]
 rand_xorshift = "0.2"
 rand_chacha = "0.2"
+ark-std = { git = "https://github.com/arkworks-rs/utils" }
 
 [features]
 default = ["rand_chacha"] # "std", 

src/lib.rs

@@ -99,9 +99,6 @@ impl<SRS: Copy+Clone> Clone for RingSRS<SRS> {
 
 #[cfg(test)]
 
-#[macro_use]
-extern crate bench_utils;
-
 mod tests {
     use std::fs::File;
 
@@ -112,6 +109,8 @@ mod tests {
     use super::*;
     use ::bls12_381::Bls12;
 
+    use ark_std::{end_timer, start_timer};
+
     #[test]
     fn test_completeness() {
         let depth = 2;