clippy-driver: pass all args after "rustc" to rustc

src/driver.rs

@@ -299,6 +299,21 @@ pub fn main() {
         rustc_driver::catch_fatal_errors(move || {
             let mut orig_args: Vec<String> = env::args().collect();
 
+            if orig_args.get(1) == Some(&"rustc".into()) {
+                // first (0) arg is the bin path, second arg is "rustc"
+                // pass all succeeding args to rustc
+                let args_for_rustc = &orig_args[2..].to_vec();
+
+                let exitstatus = Command::new("rustc")
+                    .args(args_for_rustc)
+                    .status()
+                    .unwrap()
+                    .code()
+                    .unwrap();
+
+                exit(exitstatus);
+            }
+
             if orig_args.iter().any(|a| a == "--version" || a == "-V") {
                 let version_info = rustc_tools_util::get_version_info!();
                 println!("{}", version_info);