Announcing rustup 1.29.0

rustup 1.29.0 introduces concurrent component downloads and unpacking for faster Rust toolchain installation.

• •Components can now be downloaded and unpacked concurrently during rustup update and rustup toolchain operations, a result of a GSoC 2025 project
• •rustup check now runs concurrent update checks and uses exit code 100 when updates are available, 0 when not
• •Two new host platforms are officially supported: sparcv9-sun-solaris and x86_64-pc-solaris
• •Shell auto-PATH configuration extended to tcsh and xonsh during rustup-init
• •rust-analyzer fallback to PATH binary when the rustup-managed one is not found
• •Empty environment variables are now treated as unset, allowing easier config reset