Remove RunCompiler::emitter.

It's no longer used.

compiler/rustc_interface/src/interface.rs

@@ -17,7 +17,7 @@ use rustc_session::config::{self, CheckCfg, ErrorOutputType, Input, OutputFilena
 use rustc_session::early_error;
 use rustc_session::lint;
 use rustc_session::parse::{CrateConfig, ParseSess};
-use rustc_session::{DiagnosticOutput, Session};
+use rustc_session::Session;
 use rustc_span::source_map::{FileLoader, FileName};
 use rustc_span::symbol::sym;
 use std::path::PathBuf;
@@ -247,7 +247,6 @@ pub struct Config {
     pub output_dir: Option<PathBuf>,
     pub output_file: Option<PathBuf>,
     pub file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
-    pub diagnostic_output: DiagnosticOutput,
 
     pub lint_caps: FxHashMap<lint::LintId, lint::Level>,
 
@@ -284,7 +283,6 @@ pub fn create_compiler_and_run<R>(config: Config, f: impl FnOnce(&Compiler) -> R
         config.opts,
         config.crate_cfg,
         config.crate_check_cfg,
-        config.diagnostic_output,
         config.file_loader,
         config.input_path.clone(),
         config.lint_caps,

compiler/rustc_interface/src/tests.rs

@@ -17,7 +17,7 @@ use rustc_session::config::{CFGuard, ExternEntry, LinkerPluginLto, LtoCli, Switc
 use rustc_session::lint::Level;
 use rustc_session::search_paths::SearchPath;
 use rustc_session::utils::{CanonicalizedPath, NativeLib, NativeLibKind};
-use rustc_session::{build_session, getopts, DiagnosticOutput, Session};
+use rustc_session::{build_session, getopts, Session};
 use rustc_span::edition::{Edition, DEFAULT_EDITION};
 use rustc_span::symbol::sym;
 use rustc_span::SourceFileHashAlgorithm;
@@ -40,16 +40,7 @@ fn build_session_options_and_crate_config(matches: getopts::Matches) -> (Options
 fn mk_session(matches: getopts::Matches) -> (Session, CfgSpecs) {
     let registry = registry::Registry::new(&[]);
     let (sessopts, cfg) = build_session_options_and_crate_config(matches);
-    let sess = build_session(
-        sessopts,
-        None,
-        None,
-        registry,
-        DiagnosticOutput::Default,
-        Default::default(),
-        None,
-        None,
-    );
+    let sess = build_session(sessopts, None, None, registry, Default::default(), None, None);
     (sess, cfg)
 }
 

compiler/rustc_interface/src/util.rs

@@ -18,7 +18,7 @@ use rustc_session::config::{self, CrateType};
 use rustc_session::config::{ErrorOutputType, Input, OutputFilenames};
 use rustc_session::lint::{self, BuiltinLintDiagnostics, LintBuffer};
 use rustc_session::parse::CrateConfig;
-use rustc_session::{early_error, filesearch, output, DiagnosticOutput, Session};
+use rustc_session::{early_error, filesearch, output, Session};
 use rustc_span::edition::Edition;
 use rustc_span::lev_distance::find_best_match_for_name;
 use rustc_span::source_map::FileLoader;
@@ -65,7 +65,6 @@ pub fn create_session(
     sopts: config::Options,
     cfg: FxHashSet<(String, Option<String>)>,
     check_cfg: CheckCfg,
-    diagnostic_output: DiagnosticOutput,
     file_loader: Option<Box<dyn FileLoader + Send + Sync + 'static>>,
     input_path: Option<PathBuf>,
     lint_caps: FxHashMap<lint::LintId, lint::Level>,
@@ -104,7 +103,6 @@ pub fn create_session(
         input_path,
         bundle,
         descriptions,
-        diagnostic_output,
         lint_caps,
         file_loader,
         target_override,