diff --git a/examples/json.rs b/examples/json.rs
index a9ba31e3..68b391b1 100644
--- a/examples/json.rs
+++ b/examples/json.rs
@@ -6,6 +6,8 @@
 //! isahc = { version = "*", features = ["json"]}
 //! ```
 
+#![allow(dead_code)]
+
 use isahc::{prelude::*, Request};
 
 #[derive(Debug, serde::Serialize)]
diff --git a/src/config/dial.rs b/src/config/dial.rs
index 6d7293bb..875e5823 100644
--- a/src/config/dial.rs
+++ b/src/config/dial.rs
@@ -134,7 +134,7 @@ impl FromStr for Dialer {
             if s.starts_with("unix:") {
                 // URI paths are always absolute.
                 let mut path = std::path::PathBuf::from("/");
-                path.push(&s[5..].trim_start_matches('/'));
+                path.push(s[5..].trim_start_matches('/'));
 
                 return Ok(Self(Inner::UnixSocket(path)));
             }
diff --git a/src/cookies/jar.rs b/src/cookies/jar.rs
index 46b92d64..f8484229 100644
--- a/src/cookies/jar.rs
+++ b/src/cookies/jar.rs
@@ -13,7 +13,7 @@ use std::{
 #[derive(Clone, Debug)]
 pub struct CookieRejectedError {
     kind: CookieRejectedErrorKind,
-    cookie: Cookie,
+    cookie: Box<Cookie>,
 }
 
 /// The reason why the [`Cookie`] was rejected.
@@ -35,6 +35,13 @@ pub enum CookieRejectedErrorKind {
 }
 
 impl CookieRejectedError {
+    fn new(kind: CookieRejectedErrorKind, cookie: Cookie) -> Self {
+        Self {
+            kind,
+            cookie: Box::new(cookie),
+        }
+    }
+
     /// Get the kind of error that occurred.
     pub fn kind(&self) -> CookieRejectedErrorKind {
         self.kind
@@ -42,7 +49,7 @@ impl CookieRejectedError {
 
     /// Get back the [`Cookie`] that failed to be set.
     pub fn cookie(self) -> Cookie {
-        self.cookie
+        *self.cookie
     }
 }
 
@@ -138,10 +145,10 @@ impl CookieJar {
                 "cookie '{}' dropped, no domain specified in request URI",
                 cookie.name()
             );
-            return Err(CookieRejectedError {
-                kind: CookieRejectedErrorKind::InvalidRequestDomain,
+            return Err(CookieRejectedError::new(
+                CookieRejectedErrorKind::InvalidRequestDomain,
                 cookie,
-            });
+            ));
         };
 
         // Perform some validations on the domain.
@@ -155,10 +162,10 @@ impl CookieJar {
                     request_host,
                     domain
                 );
-                return Err(CookieRejectedError {
-                    kind: CookieRejectedErrorKind::DomainMismatch,
+                return Err(CookieRejectedError::new(
+                    CookieRejectedErrorKind::DomainMismatch,
                     cookie,
-                });
+                ));
             }
 
             // Drop cookies for top-level domains.
@@ -168,10 +175,10 @@ impl CookieJar {
                     cookie.name(),
                     domain
                 );
-                return Err(CookieRejectedError {
-                    kind: CookieRejectedErrorKind::InvalidCookieDomain,
+                return Err(CookieRejectedError::new(
+                    CookieRejectedErrorKind::InvalidCookieDomain,
                     cookie,
-                });
+                ));
             }
 
             // Check the PSL for bad domain suffixes if available.
@@ -184,10 +191,10 @@ impl CookieJar {
                         cookie.name(),
                         domain
                     );
-                    return Err(CookieRejectedError {
-                        kind: CookieRejectedErrorKind::InvalidCookieDomain,
+                    return Err(CookieRejectedError::new(
+                        CookieRejectedErrorKind::InvalidCookieDomain,
                         cookie,
-                    });
+                    ));
                 }
             }
         }
diff --git a/src/handler.rs b/src/handler.rs
index f1abe25a..10b40280 100644
--- a/src/handler.rs
+++ b/src/handler.rs
@@ -167,7 +167,7 @@ impl RequestHandler {
         let mut easy = Easy2::new(handler);
         easy.get_mut().handle = easy.raw();
         let id = easy.get_ref().id();
-        easy.get_mut().span.record("id", &id);
+        easy.get_mut().span.record("id", id);
 
         (easy, future)
     }