Merge pull request #1096 from wesleywiser/musl_update

Add post for updated musl targets

Author: wesleywiser

posts/2023-05-09-Updating-musl-targets.md

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+---
+layout: post
+title: "Updating Rust's Linux musl targets"
+author: Wesley Wiser
+description: "musl targets will soon ship with musl 1.2"
+team: The Compiler Team <https://www.rust-lang.org/governance/teams/compiler>
+---
+
+Beginning with Rust 1.71 (slated for stable release on 2023-07-13), the various `*-linux-musl` targets will [ship][PR] with musl 1.2.3.
+These targets currently use musl 1.1.24.
+While musl 1.2.3 introduces some [new features][musl features], most notably [64-bit time][time64] on all platforms, it is ABI compatible with earlier musl versions.
+
+As such, this change is unlikely to affect you.
+
+# Updated targets
+
+The following targets will be updated:
+
+| Target | [Support Tier][tiers] |
+| - | - |
+| `aarch64-unknown-linux-musl` | Tier 2 with Host Tools |
+| `x86_64-unknown-linux-musl` | Tier 2 with Host Tools |
+| `arm-unknown-linux-musleabi` | Tier 2 |
+| `arm-unknown-linux-musleabihf` | Tier 2 |
+| `armv5te-unknown-linux-musleabi` | Tier 2 |
+| `armv7-unknown-linux-musleabi` | Tier 2 |
+| `armv7-unknown-linux-musleabihf` | Tier 2 |
+| `i586-unknown-linux-musl` | Tier 2 |
+| `i686-unknown-linux-musl` | Tier 2 |
+| `mips-unknown-linux-musl` | Tier 2 |
+| `mips64-unknown-linux-muslabi64` | Tier 2 |
+| `mips64el-unknown-linux-muslabi64` | Tier 2 |
+| `mipsel-unknown-linux-musl` | Tier 2 |
+| `hexagon-unknown-linux-musl` | Tier 3 |
+| `mips64-openwrt-linux-musl` | Tier 3 |
+| `powerpc-unknown-linux-musl` | Tier 3 |
+| `powerpc64-unknown-linux-musl` | Tier 3 |
+| `powerpc64le-unknown-linux-musl` | Tier 3 |
+| `riscv32gc-unknown-linux-musl` | Tier 3 |
+| `riscv64gc-unknown-linux-musl` | Tier 3 |
+| `s390x-unknown-linux-musl` | Tier 3 |
+| `thumbv7neon-unknown-linux-musleabihf` | Tier 3 |
+
+Note: musl 1.2.3 does not raise the minimum required Linux kernel version for any target.
+
+# Will 64-bit time break the `libc` crate on 32-bit targets?
+
+No, the musl project made this change carefully preserving ABI compatibility.
+The `libc` crate will continue to function correctly without modification.
+
+A future version of the `libc` crate will [update][libc PR] the definitions of time-related structures and functions to be 64-bit on all musl targets however this is blocked on the musl targets themselves first being updated.
+At present, there is no anticipated date when this change will take place and care will be taken to help the Rust ecosystem transition successfully to the updated time-related definitions.
+
+[libc PR]: https://github.com/rust-lang/libc/pull/3068
+[musl features]: https://musl.libc.org/releases.html
+[PR]: https://github.com/rust-lang/rust/pull/107129
+[tiers]: https://doc.rust-lang.org/nightly/rustc/platform-support.html
+[time64]: https://musl.libc.org/time64.html