Update MSRV to 1.42

.travis.yml

@@ -3,25 +3,19 @@ language: rust
 env:
   - TARGET=x86_64-unknown-linux-gnu
   - TARGET=riscv32imac-unknown-none-elf
+  - TARGET=riscv64imac-unknown-none-elf
+  - TARGET=riscv64gc-unknown-none-elf
 
 rust:
   - nightly
   - stable
-  - 1.31.0 # MSRV
+  - 1.42.0 # MSRV
 
 if: (branch = staging OR branch = trying OR branch = master) OR (type = pull_request AND branch = master)
 
 matrix:
   allow_failures:
     - rust: nightly
-  include:
-    - env: TARGET=riscv64imac-unknown-none-elf
-      rust: nightly
-      if: (branch = staging OR branch = trying OR branch = master) OR (type = pull_request AND branch = master)
-
-    - env: TARGET=riscv64gc-unknown-none-elf
-      rust: nightly
-      if: (branch = staging OR branch = trying OR branch = master) OR (type = pull_request AND branch = master)
 
     - env: CHECK_BLOBS=1
       rust:

CHANGELOG.md

@@ -10,7 +10,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ### Changed
 
 - `Mtvec::trap_mode()` not returns `Option<TrapMode>` (breaking change)
-- Updated Minimum Supported Rust Version to 1.31.0
+- Updated Minimum Supported Rust Version to 1.42.0
 - Use `llvm_asm!` instead of `asm!`
 
 ### Removed

README.md

@@ -12,7 +12,7 @@ This project is developed and maintained by the [RISC-V team][team].
 
 ## Minimum Supported Rust Version (MSRV)
 
-This crate is guaranteed to compile on stable Rust 1.31.0 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

src/lib.rs

@@ -2,10 +2,8 @@
 //!
 //! # Minimum Supported Rust Version (MSRV)
 //!
-//! This crate is guaranteed to compile on stable Rust 1.31 and up. It *might*
+//! This crate is guaranteed to compile on stable Rust 1.42 and up. It *might*
 //! compile with older versions but that may change in any new patch release.
-//! Note that `riscv64imac-unknown-none-elf` and `riscv64gc-unknown-none-elf` targets
-//! are not supported on stable yet.
 //!
 //! # Features
 //!