extern crate autocfg; use std::env; fn main() { let autocfg = autocfg::new(); // If the "i128" feature is explicity requested, don't bother probing for it. // It will still cause a build error if that was set improperly. if env::var_os("CARGO_FEATURE_I128").is_some() || autocfg.probe_type("i128") { autocfg::emit("has_i128"); } // The RangeBounds trait was stabilized in 1.28, so from that version onwards we // implement that trait. autocfg.emit_rustc_version(1, 28); autocfg::rerun_path("build.rs"); }