diff --git a/compiler/rustc_codegen_llvm/src/llvm_util.rs b/compiler/rustc_codegen_llvm/src/llvm_util.rs
index cb9c6269b66b..0ca51bd28831 100644
--- a/compiler/rustc_codegen_llvm/src/llvm_util.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm_util.rs
@@ -365,7 +365,7 @@ pub fn llvm_global_features(sess: &Session) -> Vec<String> {
 
                 features_string
             };
-            features.extend(features_string.split(",").map(String::from));
+            features.extend(features_string.split(',').map(String::from));
         }
         Some(_) | None => {}
     };
@@ -374,7 +374,7 @@ pub fn llvm_global_features(sess: &Session) -> Vec<String> {
         if s.is_empty() {
             return None;
         }
-        let feature = if s.starts_with("+") || s.starts_with("-") {
+        let feature = if s.starts_with('+') || s.starts_with('-') {
             &s[1..]
         } else {
             return Some(s.to_string());
diff --git a/compiler/rustc_expand/src/proc_macro_server.rs b/compiler/rustc_expand/src/proc_macro_server.rs
index ff135f60a822..b949d885900d 100644
--- a/compiler/rustc_expand/src/proc_macro_server.rs
+++ b/compiler/rustc_expand/src/proc_macro_server.rs
@@ -834,7 +834,7 @@ fn ident_name_compatibility_hack(
                                 .flat_map(|c| c.as_os_str().to_str())
                                 .find(|c| c.starts_with("js-sys"))
                             {
-                                let mut version = c.trim_start_matches("js-sys-").split(".");
+                                let mut version = c.trim_start_matches("js-sys-").split('.');
                                 if version.next() == Some("0")
                                     && version.next() == Some("3")
                                     && version
diff --git a/compiler/rustc_session/src/config.rs b/compiler/rustc_session/src/config.rs
index 2d7f5f9b321d..4e834ead17d2 100644
--- a/compiler/rustc_session/src/config.rs
+++ b/compiler/rustc_session/src/config.rs
@@ -1876,7 +1876,7 @@ fn parse_extern_dep_specs(
             )
         });
 
-        let locparts: Vec<_> = loc.split(":").collect();
+        let locparts: Vec<_> = loc.split(':').collect();
         let spec = match &locparts[..] {
             ["raw", ..] => {
                 // Don't want `:` split string
diff --git a/compiler/rustc_session/src/options.rs b/compiler/rustc_session/src/options.rs
index 172337aca3d4..65c1e001b7a7 100644
--- a/compiler/rustc_session/src/options.rs
+++ b/compiler/rustc_session/src/options.rs
@@ -684,7 +684,7 @@ mod parse {
             Some(v) => v,
         };
 
-        *slot = Some(match v.trim_end_matches("s") {
+        *slot = Some(match v.trim_end_matches('s') {
             "statement" | "stmt" => MirSpanview::Statement,
             "terminator" | "term" => MirSpanview::Terminator,
             "block" | "basicblock" => MirSpanview::Block,