Rollup merge of #136445 - bjorn3:diag_ctxt_cleanup, r=oli-obk

Couple of cleanups to DiagCtxt and EarlyDiagCtxt

compiler/rustc_driver_impl/src/args.rs

@@ -1,7 +1,6 @@
 use std::{env, error, fmt, fs, io};
 
 use rustc_session::EarlyDiagCtxt;
-use rustc_span::ErrorGuaranteed;
 
 /// Expands argfiles in command line arguments.
 #[derive(Default)]
@@ -118,22 +117,22 @@ pub fn arg_expand_all(early_dcx: &EarlyDiagCtxt, at_args: &[String]) -> Vec<Stri
 ///
 /// This function is identical to [`env::args()`] except that it emits an error when it encounters
 /// non-Unicode arguments instead of panicking.
-pub fn raw_args(early_dcx: &EarlyDiagCtxt) -> Result<Vec<String>, ErrorGuaranteed> {
-    let mut res = Ok(Vec::new());
+pub fn raw_args(early_dcx: &EarlyDiagCtxt) -> Vec<String> {
+    let mut args = Vec::new();
+    let mut guar = Ok(());
     for (i, arg) in env::args_os().enumerate() {
         match arg.into_string() {
-            Ok(arg) => {
-                if let Ok(args) = &mut res {
-                    args.push(arg);
-                }
-            }
+            Ok(arg) => args.push(arg),
             Err(arg) => {
-                res =
+                guar =
                     Err(early_dcx.early_err(format!("argument {i} is not valid Unicode: {arg:?}")))
             }
         }
     }
-    res
+    if let Err(guar) = guar {
+        guar.raise_fatal();
+    }
+    args
 }
 
 #[derive(Debug)]

compiler/rustc_driver_impl/src/lib.rs

@@ -1212,9 +1212,9 @@ pub fn catch_fatal_errors<F: FnOnce() -> R, R>(f: F) -> Result<R, FatalError> {
 
 /// Variant of `catch_fatal_errors` for the `interface::Result` return type
 /// that also computes the exit code.
-pub fn catch_with_exit_code(f: impl FnOnce() -> interface::Result<()>) -> i32 {
+pub fn catch_with_exit_code(f: impl FnOnce()) -> i32 {
     match catch_fatal_errors(f) {
-        Ok(Ok(())) => EXIT_SUCCESS,
+        Ok(()) => EXIT_SUCCESS,
         _ => EXIT_FAILURE,
     }
 }
@@ -1499,10 +1499,8 @@ pub fn main() -> ! {
     install_ice_hook(DEFAULT_BUG_REPORT_URL, |_| ());
     install_ctrlc_handler();
 
-    let exit_code = catch_with_exit_code(|| {
-        run_compiler(&args::raw_args(&early_dcx)?, &mut callbacks);
-        Ok(())
-    });
+    let exit_code =
+        catch_with_exit_code(|| run_compiler(&args::raw_args(&early_dcx), &mut callbacks));
 
     if let Some(format) = callbacks.time_passes {
         let end_rss = get_resident_set_size();