Error code E0514

Dependency compiled with different version of rustc.

Example of erroneous code:

// compiled with stable `rustc`

#[crate_type = "lib"]

// compiled with nightly `rustc`

#[crate_type = "lib"]

extern crate a; // error: found crate `a` compiled by an incompatible version
                //        of rustc

This error is caused when the version of rustc used to compile a crate, as stored in the binary's metadata, differs from the version of one of its dependencies. Many parts of Rust binaries are considered unstable. For instance, the Rust ABI is not stable between compiler versions. This means that the compiler cannot be sure about how to call a function between compiler versions, and therefore this error occurs.

This error can be fixed by:

  • Using Cargo, the Rust package manager and Rustup, the Rust toolchain installer, automatically fixing this issue.
  • Recompiling the crates with a uniform rustc version.