Change message type in bug functions.

From `impl Into<DiagnosticMessage>` to `impl Into<Cow<'static, str>>`.

Because these functions don't produce user-facing output and we don't
want their strings to be translated.

compiler/rustc_abi/src/layout.rs

@@ -1,6 +1,9 @@
+use std::borrow::{Borrow, Cow};
+use std::cmp;
 use std::fmt::{self, Write};
+use std::iter;
+use std::ops::Bound;
 use std::ops::Deref;
-use std::{borrow::Borrow, cmp, iter, ops::Bound};
 
 use rustc_index::Idx;
 use tracing::debug;
@@ -32,7 +35,7 @@ fn absent<'a, FieldIdx, VariantIdx, F>(fields: &IndexSlice<FieldIdx, F>) -> bool
 pub trait LayoutCalculator {
     type TargetDataLayoutRef: Borrow<TargetDataLayout>;
 
-    fn delayed_bug(&self, txt: String);
+    fn delayed_bug(&self, txt: impl Into<Cow<'static, str>>);
     fn current_data_layout(&self) -> Self::TargetDataLayoutRef;
 
     fn scalar_pair<FieldIdx: Idx, VariantIdx: Idx>(

compiler/rustc_errors/src/lib.rs

@@ -1076,32 +1076,36 @@ pub fn set_must_produce_diag(&self) {
 // Functions beginning with `struct_`/`create_` create a diagnostic. Other
 // functions create and emit a diagnostic all in one go.
 impl DiagCtxt {
-    // No `#[rustc_lint_diagnostics]` because bug messages aren't user-facing.
+    // No `#[rustc_lint_diagnostics]` and no `impl Into<DiagMessage>` because bug messages aren't
+    // user-facing.
     #[track_caller]
-    pub fn struct_bug(&self, msg: impl Into<DiagMessage>) -> Diag<'_, BugAbort> {
-        Diag::new(self, Bug, msg)
+    pub fn struct_bug(&self, msg: impl Into<Cow<'static, str>>) -> Diag<'_, BugAbort> {
+        Diag::new(self, Bug, msg.into())
     }
 
-    // No `#[rustc_lint_diagnostics]` because bug messages aren't user-facing.
+    // No `#[rustc_lint_diagnostics]` and no `impl Into<DiagMessage>` because bug messages aren't
+    // user-facing.
     #[track_caller]
-    pub fn bug(&self, msg: impl Into<DiagMessage>) -> ! {
+    pub fn bug(&self, msg: impl Into<Cow<'static, str>>) -> ! {
         self.struct_bug(msg).emit()
     }
 
-    // No `#[rustc_lint_diagnostics]` because bug messages aren't user-facing.
+    // No `#[rustc_lint_diagnostics]` and no `impl Into<DiagMessage>` because bug messages aren't
+    // user-facing.
     #[track_caller]
     pub fn struct_span_bug(
         &self,
         span: impl Into<MultiSpan>,
-        msg: impl Into<DiagMessage>,
+        msg: impl Into<Cow<'static, str>>,
     ) -> Diag<'_, BugAbort> {
         self.struct_bug(msg).with_span(span)
     }
 
-    // No `#[rustc_lint_diagnostics]` because bug messages aren't user-facing.
+    // No `#[rustc_lint_diagnostics]` and no `impl Into<DiagMessage>` because bug messages aren't
+    // user-facing.
     #[track_caller]
-    pub fn span_bug(&self, span: impl Into<MultiSpan>, msg: impl Into<DiagMessage>) -> ! {
-        self.struct_span_bug(span, msg).emit()
+    pub fn span_bug(&self, span: impl Into<MultiSpan>, msg: impl Into<Cow<'static, str>>) -> ! {
+        self.struct_span_bug(span, msg.into()).emit()
     }
 
     #[track_caller]
@@ -1215,24 +1219,28 @@ pub fn emit_err<'a>(&'a self, err: impl IntoDiagnostic<'a>) -> ErrorGuaranteed {
     }
 
     /// Ensures that an error is printed. See `Level::DelayedBug`.
-    // No `#[rustc_lint_diagnostics]` because bug messages aren't user-facing.
+    //
+    // No `#[rustc_lint_diagnostics]` and no `impl Into<DiagMessage>` because bug messages aren't
+    // user-facing.
     #[track_caller]
-    pub fn delayed_bug(&self, msg: impl Into<DiagMessage>) -> ErrorGuaranteed {
-        Diag::<ErrorGuaranteed>::new(self, DelayedBug, msg).emit()
+    pub fn delayed_bug(&self, msg: impl Into<Cow<'static, str>>) -> ErrorGuaranteed {
+        Diag::<ErrorGuaranteed>::new(self, DelayedBug, msg.into()).emit()
     }
 
     /// Ensures that an error is printed. See `Level::DelayedBug`.
     ///
     /// Note: this function used to be called `delay_span_bug`. It was renamed
     /// to match similar functions like `span_err`, `span_warn`, etc.
-    // No `#[rustc_lint_diagnostics]` because bug messages aren't user-facing.
+    //
+    // No `#[rustc_lint_diagnostics]` and no `impl Into<DiagMessage>` because bug messages aren't
+    // user-facing.
     #[track_caller]
     pub fn span_delayed_bug(
         &self,
         sp: impl Into<MultiSpan>,
-        msg: impl Into<DiagMessage>,
+        msg: impl Into<Cow<'static, str>>,
     ) -> ErrorGuaranteed {
-        Diag::<ErrorGuaranteed>::new(self, DelayedBug, msg).with_span(sp).emit()
+        Diag::<ErrorGuaranteed>::new(self, DelayedBug, msg.into()).with_span(sp).emit()
     }
 
     #[rustc_lint_diagnostics]

compiler/rustc_middle/src/ty/layout.rs

@@ -17,6 +17,7 @@
 use rustc_target::abi::*;
 use rustc_target::spec::{abi::Abi as SpecAbi, HasTargetSpec, PanicStrategy, Target};
 
+use std::borrow::Cow;
 use std::cmp;
 use std::fmt;
 use std::num::NonZero;
@@ -268,7 +269,7 @@ pub struct LayoutCx<'tcx, C> {
 impl<'tcx> LayoutCalculator for LayoutCx<'tcx, TyCtxt<'tcx>> {
     type TargetDataLayoutRef = &'tcx TargetDataLayout;
 
-    fn delayed_bug(&self, txt: String) {
+    fn delayed_bug(&self, txt: impl Into<Cow<'static, str>>) {
         self.tcx.dcx().delayed_bug(txt);
     }
 

compiler/rustc_middle/src/ty/sty.rs

@@ -13,7 +13,7 @@
 use crate::ty::{List, ParamEnv};
 use hir::def::DefKind;
 use rustc_data_structures::captures::Captures;
-use rustc_errors::{DiagArgValue, DiagMessage, ErrorGuaranteed, IntoDiagnosticArg, MultiSpan};
+use rustc_errors::{DiagArgValue, ErrorGuaranteed, IntoDiagnosticArg, MultiSpan};
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_hir::LangItem;
@@ -1543,7 +1543,7 @@ pub fn new_misc_error(tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
     pub fn new_error_with_message<S: Into<MultiSpan>>(
         tcx: TyCtxt<'tcx>,
         span: S,
-        msg: impl Into<DiagMessage>,
+        msg: impl Into<Cow<'static, str>>,
     ) -> Ty<'tcx> {
         let reported = tcx.dcx().span_delayed_bug(span, msg);
         Ty::new(tcx, Error(reported))

src/tools/rust-analyzer/crates/hir-ty/src/layout.rs

@@ -1,5 +1,6 @@
 //! Compute the binary representation of a type
 
+use std::borrow::Cow;
 use std::fmt;
 
 use base_db::salsa::Cycle;
@@ -114,8 +115,8 @@ struct LayoutCx<'a> {
 impl<'a> LayoutCalculator for LayoutCx<'a> {
     type TargetDataLayoutRef = &'a TargetDataLayout;
 
-    fn delayed_bug(&self, txt: String) {
-        never!("{}", txt);
+    fn delayed_bug(&self, txt: impl Into<Cow<'static, str>>) {
+        never!("{}", txt.into());
     }
 
     fn current_data_layout(&self) -> &'a TargetDataLayout {