diff --git a/src/cargo/core/compiler/build_config.rs b/src/cargo/core/compiler/build_config.rs
index 0ba59ecc947..893d9e08183 100644
--- a/src/cargo/core/compiler/build_config.rs
+++ b/src/cargo/core/compiler/build_config.rs
@@ -18,7 +18,7 @@ impl ProfileKind {
         match self {
             ProfileKind::Dev => "dev",
             ProfileKind::Release => "release",
-            ProfileKind::Custom(name) => &name,
+            ProfileKind::Custom(name) => name,
         }
     }
 }
diff --git a/src/cargo/core/compiler/build_context/mod.rs b/src/cargo/core/compiler/build_context/mod.rs
index c21938bbb3f..d2e31681607 100644
--- a/src/cargo/core/compiler/build_context/mod.rs
+++ b/src/cargo/core/compiler/build_context/mod.rs
@@ -111,7 +111,7 @@ impl<'a, 'cfg> BuildContext<'a, 'cfg> {
             None => return true,
         };
         let name = kind.short_name(self);
-        platform.matches(&name, self.cfg(kind))
+        platform.matches(name, self.cfg(kind))
     }
 
     /// Gets the user-specified linker for a particular host or target.
diff --git a/src/cargo/core/profiles.rs b/src/cargo/core/profiles.rs
index 7ea1cd1cf6c..2428285f13b 100644
--- a/src/cargo/core/profiles.rs
+++ b/src/cargo/core/profiles.rs
@@ -251,7 +251,7 @@ impl Profiles {
                 _ => {}
             };
 
-            let mut maker = self.process_chain(name, &profile, &mut set, &mut result, profiles)?;
+            let mut maker = self.process_chain(name, profile, &mut set, &mut result, profiles)?;
             result.reverse();
             maker.inherits = result;
 
@@ -263,7 +263,7 @@ impl Profiles {
 
     fn process_chain(
         &mut self,
-        name: &String,
+        name: &str,
         profile: &TomlProfile,
         set: &mut HashSet<String>,
         result: &mut Vec<TomlProfile>,
@@ -273,7 +273,7 @@ impl Profiles {
         match profile.inherits.as_ref().map(|x| x.as_str()) {
             Some(name @ "dev") | Some(name @ "release") => {
                 // These are the root profiles
-                return Ok(self.by_name.get(name).unwrap().clone());
+                Ok(self.by_name.get(name).unwrap().clone())
             }
             Some(name) => {
                 let name = name.to_owned();
diff --git a/src/cargo/ops/cargo_package.rs b/src/cargo/ops/cargo_package.rs
index a6eba3dbe86..7c43fbdd7c1 100644
--- a/src/cargo/ops/cargo_package.rs
+++ b/src/cargo/ops/cargo_package.rs
@@ -292,13 +292,11 @@ fn check_repo_state(
                 if let Ok(status) = repo.status_file(relative) {
                     if status == git2::Status::CURRENT {
                         false
+                    } else if relative.to_str().unwrap_or("") == "Cargo.lock" {
+                        // It is OK to include this file even if it is ignored.
+                        status != git2::Status::IGNORED
                     } else {
-                        if relative.to_str().unwrap_or("") == "Cargo.lock" {
-                            // It is OK to include this file even if it is ignored.
-                            status != git2::Status::IGNORED
-                        } else {
-                            true
-                        }
+                        true
                     }
                 } else {
                     submodule_dirty(file)
diff --git a/src/cargo/ops/cargo_test.rs b/src/cargo/ops/cargo_test.rs
index f49821cdfef..005b1857725 100644
--- a/src/cargo/ops/cargo_test.rs
+++ b/src/cargo/ops/cargo_test.rs
@@ -170,12 +170,12 @@ fn run_doc_tests(
             p.arg("--enable-per-target-ignores");
         }
 
-        runtool.as_ref().map(|(runtool, runtool_args)| {
+        if let Some((runtool, runtool_args)) = runtool {
             p.arg("--runtool").arg(runtool);
             for arg in runtool_args {
                 p.arg("--runtool-arg").arg(arg);
             }
-        });
+        }
 
         for &rust_dep in &[&compilation.deps_output] {
             let mut arg = OsString::from("dependency=");
diff --git a/src/cargo/ops/common_for_install_and_uninstall.rs b/src/cargo/ops/common_for_install_and_uninstall.rs
index 3fec1ee436c..9016c9c5268 100644
--- a/src/cargo/ops/common_for_install_and_uninstall.rs
+++ b/src/cargo/ops/common_for_install_and_uninstall.rs
@@ -527,7 +527,7 @@ impl InstallInfo {
         self.features == feature_set(&opts.features)
             && self.all_features == opts.all_features
             && self.no_default_features == opts.no_default_features
-            && self.profile == opts.build_config.profile_name().to_string()
+            && self.profile == opts.build_config.profile_name()
             && (self.target.is_none() || self.target.as_ref().map(|t| t.as_ref()) == Some(target))
             && &self.bins == exes
     }
diff --git a/src/cargo/util/command_prelude.rs b/src/cargo/util/command_prelude.rs
index 2d0a9b3fc5e..860ca0d2fda 100644
--- a/src/cargo/util/command_prelude.rs
+++ b/src/cargo/util/command_prelude.rs
@@ -313,10 +313,8 @@ pub trait ArgMatchesExt {
         match profile_checking {
             ProfileChecking::Unchecked => {}
             ProfileChecking::Checked => {
-                if specified_profile.is_some() {
-                    if !config.cli_unstable().unstable_options {
-                        failure::bail!("Usage of `--profile` requires `-Z unstable-options`")
-                    }
+                if specified_profile.is_some() && !config.cli_unstable().unstable_options {
+                    failure::bail!("Usage of `--profile` requires `-Z unstable-options`")
                 }
             }
         }
diff --git a/src/cargo/util/toml/mod.rs b/src/cargo/util/toml/mod.rs
index d69831752c8..91531d112a3 100644
--- a/src/cargo/util/toml/mod.rs
+++ b/src/cargo/util/toml/mod.rs
@@ -287,7 +287,7 @@ impl TomlProfiles {
                 warnings.push("use `[profile.dev]` to configure debug builds".to_string());
             }
 
-            profile.validate(&name, features, warnings)?;
+            profile.validate(name, features, warnings)?;
         }
         Ok(())
     }
@@ -490,7 +490,7 @@ impl TomlProfile {
         match &self.dir_name {
             None => {}
             Some(dir_name) => {
-                Self::validate_name(&dir_name, "dir-name")?;
+                Self::validate_name(dir_name, "dir-name")?;
             }
         }
 
@@ -498,7 +498,7 @@ impl TomlProfile {
         match &self.inherits {
             None => {}
             Some(inherits) => {
-                Self::validate_name(&inherits, "inherits")?;
+                Self::validate_name(inherits, "inherits")?;
             }
         }
 
@@ -581,7 +581,7 @@ impl TomlProfile {
         }
 
         if let Some(v) = profile.codegen_units {
-            self.codegen_units = Some(v.clone());
+            self.codegen_units = Some(v);
         }
 
         if let Some(v) = &profile.debug {
@@ -589,11 +589,11 @@ impl TomlProfile {
         }
 
         if let Some(v) = profile.debug_assertions {
-            self.debug_assertions = Some(v.clone());
+            self.debug_assertions = Some(v);
         }
 
         if let Some(v) = profile.rpath {
-            self.rpath = Some(v.clone());
+            self.rpath = Some(v);
         }
 
         if let Some(v) = &profile.panic {
@@ -601,11 +601,11 @@ impl TomlProfile {
         }
 
         if let Some(v) = profile.overflow_checks {
-            self.overflow_checks = Some(v.clone());
+            self.overflow_checks = Some(v);
         }
 
         if let Some(v) = profile.incremental {
-            self.incremental = Some(v.clone());
+            self.incremental = Some(v);
         }
 
         if let Some(v) = &profile.overrides {