bump MSRV

Required to support the #[non_exhaustive] attribute.

Author: tmplt

.github/bors.toml

@@ -3,7 +3,7 @@ delete_merged_branches = true
 required_approvals = 1
 status = [
   "ci-linux (stable)",
-  "ci-linux (1.38.0)",
+  "ci-linux (1.40.0)",
   "rustfmt",
   "clippy",
 ]

.github/workflows/ci.yml

@@ -16,7 +16,7 @@ jobs:
 
         include:
           # Test MSRV
-          - rust: 1.38.0
+          - rust: 1.40.0
 
           # Test nightly but don't fail
           - rust: nightly

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 1.38 and up. It might compile with older versions but that may change in any new patch release.
+This crate is guaranteed to compile on stable Rust 1.40 and up. It might compile with older versions but that may change in any new patch release.
 
 ## License
 

src/lib.rs

@@ -52,7 +52,7 @@
 //!
 //! # Minimum Supported Rust Version (MSRV)
 //!
-//! This crate is guaranteed to compile on stable Rust 1.38 and up. It *might*
+//! This crate is guaranteed to compile on stable Rust 1.40 and up. It *might*
 //! compile with older versions but that may change in any new patch release.
 
 #![cfg_attr(feature = "inline-asm", feature(asm))]