165     // check-cfg is a nightly cargo/rustc feature to warn when unknown cfgs are used across the  in main()
173                 println!("cargo:rustc-check-cfg=cfg({})", cfg);  in main()
175                 println!("cargo:rustc-check-cfg=values({})", cfg);  in main()
181                 println!("cargo:rustc-check-cfg=cfg({},values(\"{}\"))", name, values);  in main()
183                 println!("cargo:rustc-check-cfg=values({},\"{}\")", name, values);  in main()
194                 None => panic!("Failed to get rustc version"),  in rustc_minor_nightly()
199     let rustc = otry!(env::var_os("RUSTC"));  in rustc_minor_nightly()  localVariable
200     let output = Command::new(rustc)  in rustc_minor_nightly()
204         .expect("Failed to get rustc version");  in rustc_minor_nightly()
207             "failed to run rustc: {}",  in rustc_minor_nightly()
215     if pieces.next() != Some("rustc 1") {  in rustc_minor_nightly()
216         panic!("Failed to get rustc version");  in rustc_minor_nightly()
221     // If `rustc` was built from a tarball, its version string  in rustc_minor_nightly()
223     // (e.g. "rustc 1.39.0"). Treat this case as non-nightly,  in rustc_minor_nightly()
296     println!("cargo:rustc-cfg={}", cfg);  in set_cfg()