Remove redundant format!s

compiler/rustc_resolve/src/diagnostics.rs

@@ -1014,7 +1014,7 @@ impl<'a> Resolver<'a> {
             }
             ResolutionError::InvalidAsmSym => {
                 let mut err = self.session.struct_span_err(span, "invalid `sym` operand");
-                err.span_label(span, &format!("is a local variable"));
+                err.span_label(span, "is a local variable");
                 err.help("`sym` operands must refer to either a function or a static");
                 err
             }

compiler/rustc_resolve/src/late.rs

@@ -1696,7 +1696,7 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
                     "invalid lifetime parameter name: `{}`",
                     param.ident,
                 )
-                .span_label(param.ident.span, format!("'static is a reserved lifetime name"))
+                .span_label(param.ident.span, "'static is a reserved lifetime name")
                 .emit();
                 continue;
             }

compiler/rustc_typeck/src/check/fn_ctxt/checks.rs

@@ -968,9 +968,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 SuggestionText::Remove(plural) => {
                     Some(format!("remove the extra argument{}", if plural { "s" } else { "" }))
                 }
-                SuggestionText::Swap => Some(format!("swap these arguments")),
-                SuggestionText::Reorder => Some(format!("reorder these arguments")),
-                SuggestionText::DidYouMean => Some(format!("did you mean")),
+                SuggestionText::Swap => Some("swap these arguments".to_string()),
+                SuggestionText::Reorder => Some("reorder these arguments".to_string()),
+                SuggestionText::DidYouMean => Some("did you mean".to_string()),
             };
             if let Some(suggestion_text) = suggestion_text {
                 let source_map = self.sess().source_map();