diff --git a/build.rs b/build.rs
index 9b83e35..f413251 100644
--- a/build.rs
+++ b/build.rs
@@ -16,7 +16,7 @@ fn main() {
         }
     }
 
-    let var = std::env::var_os("SHELL_COMPLETIONS_DIR").or(std::env::var_os("OUT_DIR"));
+    let var = std::env::var_os("SHELL_COMPLETIONS_DIR").or_else(|| std::env::var_os("OUT_DIR"));
     let outdir = match var {
         None => return,
         Some(outdir) => outdir,
diff --git a/src/hyperfine/app.rs b/src/hyperfine/app.rs
index a715291..1573f13 100644
--- a/src/hyperfine/app.rs
+++ b/src/hyperfine/app.rs
@@ -1,4 +1,3 @@
-use atty;
 use atty::Stream;
 use clap::{crate_version, App, AppSettings, Arg, ArgMatches};
 use std::ffi::OsString;
diff --git a/src/hyperfine/internal.rs b/src/hyperfine/internal.rs
index 5e1aaf0..7139aad 100644
--- a/src/hyperfine/internal.rs
+++ b/src/hyperfine/internal.rs
@@ -29,7 +29,7 @@ pub fn get_progress_bar(length: u64, msg: &str, option: OutputStyleOption) -> Pr
         OutputStyleOption::Basic | OutputStyleOption::Color => ProgressBar::hidden(),
         _ => ProgressBar::new(length),
     };
-    progress_bar.set_style(progressbar_style.clone());
+    progress_bar.set_style(progressbar_style);
     progress_bar.enable_steady_tick(TICK_SETTINGS.1);
     progress_bar.set_message(msg.to_owned());
 
@@ -64,9 +64,9 @@ fn compare_mean_time(l: &BenchmarkResult, r: &BenchmarkResult) -> Ordering {
     l.mean.partial_cmp(&r.mean).unwrap_or(Ordering::Equal)
 }
 
-pub fn compute_relative_speed<'a>(
-    results: &'a [BenchmarkResult],
-) -> Option<Vec<BenchmarkResultWithRelativeSpeed<'a>>> {
+pub fn compute_relative_speed (
+    results: & [BenchmarkResult],
+) -> Option<Vec<BenchmarkResultWithRelativeSpeed>> {
     let fastest: &BenchmarkResult = results
         .iter()
         .min_by(|&l, &r| compare_mean_time(l, r))
@@ -188,7 +188,7 @@ fn test_compute_relative_speed_for_zero_times() {
     assert!(annotated_results.is_none());
 }
 
-pub fn tokenize<'a>(values: &'a str) -> Vec<String> {
+pub fn tokenize(values: &str) -> Vec<String> {
     let mut tokens = vec![];
     let mut buf = String::new();
 
diff --git a/src/hyperfine/shell.rs b/src/hyperfine/shell.rs
index 48162fe..6bb3ec0 100644
--- a/src/hyperfine/shell.rs
+++ b/src/hyperfine/shell.rs
@@ -1,4 +1,3 @@
-use std;
 use std::io;
 use std::process::{Command, ExitStatus, Stdio};
 
diff --git a/src/hyperfine/timer/unix_timer.rs b/src/hyperfine/timer/unix_timer.rs
index f65b207..802be5d 100644
--- a/src/hyperfine/timer/unix_timer.rs
+++ b/src/hyperfine/timer/unix_timer.rs
@@ -51,10 +51,10 @@ fn get_cpu_times() -> CPUTimes {
     const MICROSEC_PER_SEC: i64 = 1000 * 1000;
 
     CPUTimes {
-        user_usec: i64::from(result.ru_utime.tv_sec) * MICROSEC_PER_SEC
-            + i64::from(result.ru_utime.tv_usec),
-        system_usec: i64::from(result.ru_stime.tv_sec) * MICROSEC_PER_SEC
-            + i64::from(result.ru_stime.tv_usec),
+        user_usec: result.ru_utime.tv_sec * MICROSEC_PER_SEC
+            + result.ru_utime.tv_usec,
+        system_usec: result.ru_stime.tv_sec * MICROSEC_PER_SEC
+            + result.ru_stime.tv_usec,
     }
 }