[][src]Function syntax_ext::deriving::warn_if_deprecated

fn warn_if_deprecated(ecx: &mut ExtCtxt, sp: Span, name: &str)
🔬 This is a nightly-only experimental API. (rustc_private)

this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via Cargo.toml instead?