rustc-ap-rustc_cratesio_shim 503.0.0

Automatically published version of the package `rustc_cratesio_shim` in the rust-lang/rust repository from commit 7d107613498c500699dcf89aab7231c28a8fa3af The publishing script for this crate lives at: https://github.com/alexcrichton/rustc-auto-publish