Remove one use of dummy_config

Author: bjorn3

compiler/rustc_driver/src/lib.rs

@@ -197,12 +197,7 @@ fn run_compiler(
     let sopts = config::build_session_options(&matches);
     let cfg = interface::parse_cfgspecs(matches.opt_strs("cfg"));
 
-    // We wrap `make_codegen_backend` in another `Option` such that `dummy_config` can take
-    // ownership of it when necessary, while also allowing the non-dummy config to take ownership
-    // when `dummy_config` is not used.
-    let mut make_codegen_backend = Some(make_codegen_backend);
-
-    let mut dummy_config = |sopts, cfg, diagnostic_output| {
+    let mut dummy_config = |sopts, cfg, diagnostic_output, make_codegen_backend| {
         let mut config = interface::Config {
             opts: sopts,
             crate_cfg: cfg,
@@ -217,7 +212,7 @@ fn run_compiler(
             parse_sess_created: None,
             register_lints: None,
             override_queries: None,
-            make_codegen_backend: make_codegen_backend.take().unwrap(),
+            make_codegen_backend,
             registry: diagnostics_registry(),
         };
         callbacks.config(&mut config);
@@ -234,7 +229,7 @@ fn run_compiler(
         Some(v) => v,
         None => match matches.free.len() {
             0 => {
-                let config = dummy_config(sopts, cfg, diagnostic_output);
+                let config = dummy_config(sopts, cfg, diagnostic_output, make_codegen_backend);
                 interface::run_compiler(config, |compiler| {
                     let sopts = &compiler.session().opts;
                     if sopts.describe_lints {
@@ -281,10 +276,7 @@ fn run_compiler(
     if let Some(err) = input_err {
         // Immediately stop compilation if there was an issue reading
         // the input (for example if the input stream is not UTF-8).
-        interface::run_compiler(dummy_config(sopts, cfg, diagnostic_output), |compiler| {
-            compiler.session().err(&err.to_string());
-        });
-        return Err(ErrorReported);
+        early_error(sopts.error_format, &err.to_string());
     }
 
     let mut config = interface::Config {
@@ -301,7 +293,7 @@ fn run_compiler(
         parse_sess_created: None,
         register_lints: None,
         override_queries: None,
-        make_codegen_backend: make_codegen_backend.unwrap(),
+        make_codegen_backend,
         registry: diagnostics_registry(),
     };