diff --git a/src/librustc_driver/lib.rs b/src/librustc_driver/lib.rs index d89a3e9d907..b9b36616e69 100644 --- a/src/librustc_driver/lib.rs +++ b/src/librustc_driver/lib.rs @@ -1136,6 +1136,16 @@ fn usage(verbose: bool, include_unstable_options: bool) { verbose_help); } +fn print_wall_help() { + println!(" +The flag -Wall does not exist in rustc. Most useful lints are enabled by default. +Use `rustc -W help` to see all available lints. The most used lints that are not +enabled by default covered by -Wunused; however, the best practice is to put +warning settings in the crate root using `#![warn(unused)]` instead of using +the command line flag directly. +"); +} + fn describe_lints(sess: &Session, lint_store: &lint::LintStore, loaded_plugins: bool) { println!(" Available lint options: @@ -1379,6 +1389,13 @@ pub fn handle_options(args: &[String]) -> Option { nightly_options::is_unstable_enabled(&matches)); return None; } + + // Handle the special case of -Wall. + let wall = matches.opt_strs("W"); + if wall.iter().any(|x| *x == "all") { + print_wall_help(); + return None; + } // Don't handle -W help here, because we might first load plugins. let r = matches.opt_strs("Z");