Avoid ref when using format! in compiler

Clean up a few minor refs in `format!` macro, as it has a performance cost. Apparently the compiler is unable to inline `format!("{}", &variable)`, and does a run-time double-reference instead (format macro already does one level referencing).  Inlining format args prevents accidental `&` misuse.

3 files changed, 5 insertions, 5 deletions

diff --git a/compiler/rustc_resolve/src/diagnostics.rs b/compiler/rustc_resolve/src/diagnostics.rs
index 7c0405c87e0..bf7972e392c 100644
--- a/compiler/rustc_resolve/src/diagnostics.rs
+++ b/compiler/rustc_resolve/src/diagnostics.rs
@@ -149,7 +149,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                     BuiltinLintDiag::AmbiguousGlobImports { diag },
                 );
             } else {
-                let mut err = struct_span_code_err!(self.dcx(), diag.span, E0659, "{}", &diag.msg);
+                let mut err = struct_span_code_err!(self.dcx(), diag.span, E0659, "{}", diag.msg);
                 report_ambiguity_error(&mut err, diag);
                 err.emit();
             }
@@ -798,7 +798,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             }
             ResolutionError::FailedToResolve { segment, label, suggestion, module } => {
                 let mut err =
-                    struct_span_code_err!(self.dcx(), span, E0433, "failed to resolve: {}", &label);
+                    struct_span_code_err!(self.dcx(), span, E0433, "failed to resolve: {label}");
                 err.span_label(span, label);
 
                 if let Some((suggestions, msg, applicability)) = suggestion {
@@ -2893,7 +2893,7 @@ fn show_candidates(
                     ""
                 };
                 candidate.0 =
-                    format!("{add_use}{}{append}{trailing}{additional_newline}", &candidate.0);
+                    format!("{add_use}{}{append}{trailing}{additional_newline}", candidate.0);
             }
 
             match mode {
diff --git a/compiler/rustc_resolve/src/imports.rs b/compiler/rustc_resolve/src/imports.rs
index 3896fe4c4fa..d05326ee311 100644
--- a/compiler/rustc_resolve/src/imports.rs
+++ b/compiler/rustc_resolve/src/imports.rs
@@ -694,7 +694,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             .collect::<Vec<_>>();
         let msg = format!("unresolved import{} {}", pluralize!(paths.len()), paths.join(", "),);
 
-        let mut diag = struct_span_code_err!(self.dcx(), span, E0432, "{}", &msg);
+        let mut diag = struct_span_code_err!(self.dcx(), span, E0432, "{msg}");
 
         if let Some((_, UnresolvedImportError { note: Some(note), .. })) = errors.iter().last() {
             diag.note(note.clone());
diff --git a/compiler/rustc_resolve/src/rustdoc.rs b/compiler/rustc_resolve/src/rustdoc.rs
index 59460815321..4c49c15c472 100644
--- a/compiler/rustc_resolve/src/rustdoc.rs
+++ b/compiler/rustc_resolve/src/rustdoc.rs
@@ -339,7 +339,7 @@ pub fn strip_generics_from_path(path_str: &str) -> Result<Box<str>, MalformedGen
         }
     }
 
-    debug!("path_str: {:?}\nstripped segments: {:?}", path_str, &stripped_segments);
+    debug!("path_str: {path_str:?}\nstripped segments: {stripped_segments:?}");
 
     let stripped_path = stripped_segments.join("::");