Auto merge of #118143 - Nilstrieb:only-borrow-what-you-need, r=compiler-errors

Fix `clippy::needless_borrow` in the compiler

`x clippy compiler -Aclippy::all -Wclippy::needless_borrow --fix`.

Then I had to remove a few unnecessary parens and muts that were exposed now.

r? `@compiler-errors` you told me you want to review this

I will do a self review first (which, for this, is easiest on GitHub once the PR is open) - did it

2 files changed, 11 insertions, 11 deletions

diff --git a/compiler/rustc_interface/src/passes.rs b/compiler/rustc_interface/src/passes.rs
index 0baf77c4f7e..ec024dac8dd 100644
--- a/compiler/rustc_interface/src/passes.rs
+++ b/compiler/rustc_interface/src/passes.rs
@@ -127,7 +127,7 @@ fn configure_and_expand(
     let tcx = resolver.tcx();
     let sess = tcx.sess;
     let features = tcx.features();
-    let lint_store = unerased_lint_store(&tcx.sess);
+    let lint_store = unerased_lint_store(tcx.sess);
     let crate_name = tcx.crate_name(LOCAL_CRATE);
     let lint_check_node = (&krate, pre_configured_attrs);
     pre_expansion_lint(
@@ -150,7 +150,7 @@ fn configure_and_expand(
         )
     });
 
-    util::check_attr_crate_type(sess, pre_configured_attrs, &mut resolver.lint_buffer());
+    util::check_attr_crate_type(sess, pre_configured_attrs, resolver.lint_buffer());
 
     // Expand all macros
     krate = sess.time("macro_expand_crate", || {
@@ -284,16 +284,16 @@ fn early_lint_checks(tcx: TyCtxt<'_>, (): ()) {
     let mut lint_buffer = resolver.lint_buffer.steal();
 
     if sess.opts.unstable_opts.input_stats {
-        eprintln!("Post-expansion node count: {}", count_nodes(&krate));
+        eprintln!("Post-expansion node count: {}", count_nodes(krate));
     }
 
     if sess.opts.unstable_opts.hir_stats {
-        hir_stats::print_ast_stats(&krate, "POST EXPANSION AST STATS", "ast-stats-2");
+        hir_stats::print_ast_stats(krate, "POST EXPANSION AST STATS", "ast-stats-2");
     }
 
     // Needs to go *after* expansion to be able to check the results of macro expansion.
     sess.time("complete_gated_feature_checking", || {
-        rustc_ast_passes::feature_gate::check_crate(&krate, sess, tcx.features());
+        rustc_ast_passes::feature_gate::check_crate(krate, sess, tcx.features());
     });
 
     // Add all buffered lints from the `ParseSess` to the `Session`.
@@ -319,7 +319,7 @@ fn early_lint_checks(tcx: TyCtxt<'_>, (): ()) {
         }
     });
 
-    let lint_store = unerased_lint_store(&tcx.sess);
+    let lint_store = unerased_lint_store(tcx.sess);
     rustc_lint::check_ast_node(
         sess,
         tcx.features(),
@@ -521,11 +521,11 @@ fn write_out_deps(tcx: TyCtxt<'_>, outputs: &OutputFilenames, out_filenames: &[P
             if sess.opts.json_artifact_notifications {
                 sess.parse_sess
                     .span_diagnostic
-                    .emit_artifact_notification(&deps_filename, "dep-info");
+                    .emit_artifact_notification(deps_filename, "dep-info");
             }
         }
         Err(error) => {
-            sess.emit_fatal(errors::ErrorWritingDependencies { path: &deps_filename, error });
+            sess.emit_fatal(errors::ErrorWritingDependencies { path: deps_filename, error });
         }
     }
 }
@@ -564,12 +564,12 @@ fn output_filenames(tcx: TyCtxt<'_>, (): ()) -> Arc<OutputFilenames> {
         generated_output_paths(tcx, &outputs, sess.io.output_file.is_some(), crate_name);
 
     // Ensure the source file isn't accidentally overwritten during compilation.
-    if let Some(ref input_path) = sess.io.input.opt_path() {
+    if let Some(input_path) = sess.io.input.opt_path() {
         if sess.opts.will_create_output_file() {
             if output_contains_path(&output_paths, input_path) {
                 sess.emit_fatal(errors::InputFileWouldBeOverWritten { path: input_path });
             }
-            if let Some(ref dir_path) = output_conflicts_with_dir(&output_paths) {
+            if let Some(dir_path) = output_conflicts_with_dir(&output_paths) {
                 sess.emit_fatal(errors::GeneratedFileConflictsWithDirectory {
                     input_path,
                     dir_path,
diff --git a/compiler/rustc_interface/src/queries.rs b/compiler/rustc_interface/src/queries.rs
index fbf2dbcdae5..3fee2d28981 100644
--- a/compiler/rustc_interface/src/queries.rs
+++ b/compiler/rustc_interface/src/queries.rs
@@ -102,7 +102,7 @@ impl<'tcx> Queries<'tcx> {
     }
 
     fn session(&self) -> &Session {
-        &self.compiler.session()
+        self.compiler.session()
     }
 
     fn codegen_backend(&self) -> &dyn CodegenBackend {