Error code E0457

Note: this error code is no longer emitted by the compiler

Plugin .. only found in rlib format, but must be available in dylib format.

Erroneous code example:

rlib-plugin.rs

#![crate_type = "rlib"] #![feature(rustc_private)] extern crate rustc_middle; extern crate rustc_driver; use rustc_driver::plugin::Registry; #[no_mangle] fn __rustc_plugin_registrar(_: &mut Registry) {}

main.rs

#![feature(plugin)] #![plugin(rlib_plugin)] // error: plugin `rlib_plugin` only found in rlib // format, but must be available in dylib fn main() {}

The compiler exposes a plugin interface to allow altering the compile process (adding lints, etc). Plugins must be defined in their own crates (similar to proc-macro isolation) and then compiled and linked to another crate. Plugin crates must be compiled to the dynamically-linked dylib format, and not the statically-linked rlib format. Learn more about different output types in this section of the Rust reference.

This error is easily fixed by recompiling the plugin crate in the dylib format.