Merge #415

415: Fix most clippy lints r=adamgreig a=newAM

This fixes all clippy lints that do not result in a user-visible change, and result in valid code for the 1.40 MSRV.

Co-authored-by: Alex Martens <alex@thinglab.org>

3 files changed, 7 insertions, 13 deletions

diff --git a/cortex-m-rt/README.md b/cortex-m-rt/README.md
index 9857720..34b0f17 100644
--- a/cortex-m-rt/README.md
+++ b/cortex-m-rt/README.md
@@ -11,7 +11,7 @@ This project is developed and maintained by the [Cortex-M team][team].
 
 # Minimum Supported Rust Version (MSRV)
 
-This crate is guaranteed to compile on stable Rust 1.40.0 and up. It *might*
+This crate is guaranteed to compile on stable Rust 1.42.0 and up. It *might*
 compile with older versions but that may change in any new patch release.
 
 # License
diff --git a/cortex-m-rt/macros/src/lib.rs b/cortex-m-rt/macros/src/lib.rs
index 817e9a1..24f3fa1 100644
--- a/cortex-m-rt/macros/src/lib.rs
+++ b/cortex-m-rt/macros/src/lib.rs
@@ -28,10 +28,7 @@ pub fn entry(args: TokenStream, input: TokenStream) -> TokenStream {
         && f.sig.variadic.is_none()
         && match f.sig.output {
             ReturnType::Default => false,
-            ReturnType::Type(_, ref ty) => match **ty {
-                Type::Never(_) => true,
-                _ => false,
-            },
+            ReturnType::Type(_, ref ty) => matches!(**ty, Type::Never(_)),
         };
 
     if !valid_signature {
@@ -159,7 +156,7 @@ pub fn exception(args: TokenStream, input: TokenStream) -> TokenStream {
             Exception::DefaultHandler | Exception::HardFault | Exception::NonMaskableInt => {
                 // These are unsafe to define.
                 let name = if exn == Exception::DefaultHandler {
-                    format!("`DefaultHandler`")
+                    "`DefaultHandler`".to_string()
                 } else {
                     format!("`{:?}` handler", exn)
                 };
@@ -252,10 +249,7 @@ pub fn exception(args: TokenStream, input: TokenStream) -> TokenStream {
                 && f.sig.variadic.is_none()
                 && match f.sig.output {
                     ReturnType::Default => false,
-                    ReturnType::Type(_, ref ty) => match **ty {
-                        Type::Never(_) => true,
-                        _ => false,
-                    },
+                    ReturnType::Type(_, ref ty) => matches!(**ty, Type::Never(_)),
                 };
 
             if !valid_signature {
@@ -557,7 +551,7 @@ fn extract_static_muts(
     let mut seen = HashSet::new();
     let mut statics = vec![];
     let mut stmts = vec![];
-    while let Some(stmt) = istmts.next() {
+    for stmt in istmts.by_ref() {
         match stmt {
             Stmt::Item(Item::Static(var)) => {
                 if var.mutability.is_some() {
@@ -622,7 +616,7 @@ fn check_attr_whitelist(attrs: &[Attribute], caller: WhiteListCaller) -> Result<
 
     'o: for attr in attrs {
         for val in whitelist {
-            if eq(&attr, &val) {
+            if eq(attr, val) {
                 continue 'o;
             }
         }
diff --git a/cortex-m-rt/src/lib.rs b/cortex-m-rt/src/lib.rs
index 8003326..752d3d7 100644
--- a/cortex-m-rt/src/lib.rs
+++ b/cortex-m-rt/src/lib.rs
@@ -418,7 +418,7 @@
 //!
 //! # Minimum Supported Rust Version (MSRV)
 //!
-//! The MSRV of this release is Rust 1.40.0.
+//! The MSRV of this release is Rust 1.42.0.
 
 // # Developer notes
 //