RS.CLIPPY.MULTIPLE_CRATE_VERSIONS

Multiple versions of the same crate being used

This checker is a Clippy lint created by The Rust Project Contributors. The documentation shown here is a copy of the original documentation for: multiple_crate_versions. Copyright ©2025 The Rust Team. All rights reserved.

What it does

Checks to see if multiple versions of a crate are being used.

Why is this bad?

This bloats the size of targets, and can lead to confusing error messages when structs or traits are used interchangeably between different versions of a crate.

Known problems

Because this can be caused purely by the dependencies themselves, it's not always possible to fix this issue. In those cases, you can allow that specific crate using the allowed_duplicate_crates configuration option.

Example

[dependencies]
ctrlc = "=3.1.0"
ansi_term = "=0.11.0"

Configuration

  • allowed-duplicate-crates: A list of crate names to allow duplicates of

    (default: [])