Constant rustc::hir::def_id::BUILTIN_MACROS_CRATE

pub const BUILTIN_MACROS_CRATE: CrateNum = CrateNum(u32::MAX)

🔬 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?

Virtual crate for builtin macros