lang: Fix bytemuck_derive build error

[acheroncrypto]

Problem

anchor-lang doesn't compile due to an update to the bytemuck_derive crate.

error: rustc 1.79.0-dev is not supported by the following package:

                 Note that this is the rustc version that ships with Solana tools and not your system's rustc version. Use `solana-install update` or head over to https://docs.solanalabs.com/cli/install to install a newer version.
  bytemuck_derive@1.9.2 requires rustc 1.84
Either upgrade rustc or select compatible dependency versions with
`cargo update <name>@<current-ver> --precise <compatible-ver>`
where `<compatible-ver>` is the latest version supporting rustc 1.79.0-dev

As the error message suggests, the latest version of the bytemuck_derive crate specifies MSRV as 1.84, which is incompatible with the Rust version coming from the latest Solana version (1.79.0).

This is one of the issues with Rust's dependency management where even though anchor-lang only depends on bytemuck, and doesn't have its derive feature enabled, cargo refuses to build even when bytemuck_derive is an optional dependency that isn't enabled.

In stable Rust 1.84, cargo supports trying to fallback to a supported version instead of returning an error, which should fix many issues similar to this one. See:

• Rust 1.84.0 release notes
• https://rust-lang.github.io/rfcs/3537-msrv-resolver.html
• RFC: Make Cargo respect minimum supported Rust version (MSRV) when selecting dependencies rust-lang/rfcs#3537
• MSRV-dependent dependency version resolution rust-lang/cargo#9930

Summary of changes

Add bytemuck_derive version requirement to be >1.0.0, <1.9.

This is a short term fix that will be removed once Solana build tools are on Rust >=1.84 (currently 1.79.0).

Fixes #3606

[vercel]

@acheroncrypto is attempting to deploy a commit to the coral-xyz Team on Vercel.

A member of the Team first needs to authorize it.

[Gizmor108]

i got this same error what should i do ?

error: rustc 1.79.0-dev is not supported by the following package:

             Note that this is the rustc version that ships with Solana tools and not your system's rustc version. Use `solana-install update` or head over to https://docs.solanalabs.com/cli/install to install a newer version.

indexmap@2.12.1 requires rustc 1.82
Either upgrade rustc or select compatible dependency versions with
cargo update <name>@<current-ver> --precise <compatible-ver>
where <compatible-ver> is the latest version supporting rustc 1.79.0-dev

[acheroncrypto]

i got this same error what should i do ?

You should update your Solana tooling version or downgrade problematic versions of crates like in this PR.