Static rustc_lint::builtin::MUTABLE_TRANSMUTES[]

static MUTABLE_TRANSMUTES: &Lint = &::lint::Lint{name: "MUTABLE_TRANSMUTES",
              default_level: ::lint::Deny,
              desc:
                  "mutating transmuted &mut T from &T may cause undefined behavior",
              edition_lint_opts: None,
              report_in_external_macro: false,}
🔬 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?