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rust-version

The oldest Rust release a project promises to build with.

rust-version in Cargo.toml declares the minimum supported Rust version (MSRV); Cargo refuses older toolchains.

Examples

  • With rust-version = "1.99" in [package], cargo build on Rust 1.98.1 stops with "rustc 1.98.1 is not supported by the following package".

See also

edition Cargo.toml toolchain
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