diff options
| -rw-r--r-- | Cargo.toml | 5 | ||||
| -rw-r--r-- | src/lib.rs | 26 |
2 files changed, 26 insertions, 5 deletions
@@ -24,11 +24,6 @@ embedded-hal = "0.2.4" [features] cm7-r0p1 = [] inline-asm = [] - -# Link against prebuilt assembly blobs that are compatible with Linker-Plugin LTO. -# When using this feature, you *must* pass `-Clinker-plugin-lto` to rustc. See this link for -# details: -# https://doc.rust-lang.org/stable/rustc/linker-plugin-lto.html linker-plugin-lto = [] [workspace] @@ -24,6 +24,32 @@ //! //! The disadvantage is that `inline-asm` requires a nightly toolchain. //! +//! ## `cm7-r0p1` +//! +//! This feature enables workarounds for errata found on Cortex-M7 chips with revision r0p1. Some +//! functions in this crate only work correctly on those chips if this Cargo feature is enabled +//! (the functions are documented accordingly). +//! +//! ## `linker-plugin-lto` +//! +//! This feature links against prebuilt assembly blobs that are compatible with [Linker-Plugin LTO]. +//! This allows inlining assembly routines into the caller, even without the `inline-asm` feature, +//! and works on stable Rust (but note the drawbacks below!). +//! +//! If you want to use this feature, you need to be aware of a few things: +//! +//! - You need to make sure that `-Clinker-plugin-lto` is passed to rustc. Please refer to the +//! [Linker-Plugin LTO] documentation for details. +//! +//! - You have to use a Rust version whose LLVM version is compatible with the toolchain in +//! `asm-toolchain`. +//! +//! - Due to a [Rust bug][rust-lang/rust#75940], this option does not work with optimization +//! levels `s` and `z`. +//! +//! [Linker-Plugin LTO]: https://doc.rust-lang.org/stable/rustc/linker-plugin-lto.html +//! [rust-lang/rust#75940]: https://github.com/rust-lang/rust/issues/75940 +//! //! # Minimum Supported Rust Version (MSRV) //! //! This crate is guaranteed to compile on stable Rust 1.31 and up. It *might* |