Auto merge of #119146 - nnethercote:rm-DiagCtxt-api-duplication, r=compiler-errors

Remove `DiagCtxt` API duplication

`DiagCtxt` defines the internal API for creating and emitting diagnostics: methods like `struct_err`, `struct_span_warn`, `note`, `create_fatal`, `emit_bug`. There are over 50 methods.

Some of these methods are then duplicated across several other types: `Session`, `ParseSess`, `Parser`, `ExtCtxt`, and `MirBorrowckCtxt`. `Session` duplicates the most, though half the ones it does are unused. Each duplicated method just calls forward to the corresponding method in `DiagCtxt`. So this duplication exists to (in the best case) shorten chains like `ecx.tcx.sess.parse_sess.dcx.emit_err()` to `ecx.emit_err()`.

This API duplication is ugly and has been bugging me for a while. And it's inconsistent: there's no real logic about which methods are duplicated, and the use of `#[rustc_lint_diagnostic]` and `#[track_caller]` attributes vary across the duplicates.

This PR removes the duplicated API methods and makes all diagnostic creation and emission go through `DiagCtxt`. It also adds `dcx` getter methods to several types to shorten chains. This approach scales *much* better than API duplication; indeed, the PR adds `dcx()` to numerous types that didn't have API duplication: `TyCtxt`, `LoweringCtxt`, `ConstCx`, `FnCtxt`, `TypeErrCtxt`, `InferCtxt`, `CrateLoader`, `CheckAttrVisitor`, and `Resolver`. These result in a lot of changes from `foo.tcx.sess.emit_err()` to `foo.dcx().emit_err()`. (You could do this with more types, but it gets into diminishing returns territory for types that don't emit many diagnostics.)

After all these changes, some call sites are more verbose, some are less verbose, and many are the same. The total number of lines is reduced, mostly because of the removed API duplication. And consistency is increased, because calls to `emit_err` and friends are always preceded with `.dcx()` or `.dcx`.

r? `@compiler-errors`

16 files changed, 79 insertions, 69 deletions

diff --git a/compiler/rustc_codegen_cranelift/src/abi/mod.rs b/compiler/rustc_codegen_cranelift/src/abi/mod.rs
index 2c194f6d6d3..795c8daec6a 100644
--- a/compiler/rustc_codegen_cranelift/src/abi/mod.rs
+++ b/compiler/rustc_codegen_cranelift/src/abi/mod.rs
@@ -47,12 +47,12 @@ pub(crate) fn conv_to_call_conv(sess: &Session, c: Conv, default_call_conv: Call
         }
 
         Conv::X86Intr | Conv::RiscvInterrupt { .. } => {
-            sess.fatal(format!("interrupt call conv {c:?} not yet implemented"))
+            sess.dcx().fatal(format!("interrupt call conv {c:?} not yet implemented"))
         }
 
-        Conv::ArmAapcs => sess.fatal("aapcs call conv not yet implemented"),
+        Conv::ArmAapcs => sess.dcx().fatal("aapcs call conv not yet implemented"),
         Conv::CCmseNonSecureCall => {
-            sess.fatal("C-cmse-nonsecure-call call conv is not yet implemented");
+            sess.dcx().fatal("C-cmse-nonsecure-call call conv is not yet implemented");
         }
 
         Conv::Msp430Intr
@@ -88,10 +88,10 @@ pub(crate) fn import_function<'tcx>(
     let sig = get_function_sig(tcx, module.target_config().default_call_conv, inst);
     match module.declare_function(name, Linkage::Import, &sig) {
         Ok(func_id) => func_id,
-        Err(ModuleError::IncompatibleDeclaration(_)) => tcx.sess.fatal(format!(
+        Err(ModuleError::IncompatibleDeclaration(_)) => tcx.dcx().fatal(format!(
             "attempt to declare `{name}` as function, but it was already declared as static"
         )),
-        Err(ModuleError::IncompatibleSignature(_, prev_sig, new_sig)) => tcx.sess.fatal(format!(
+        Err(ModuleError::IncompatibleSignature(_, prev_sig, new_sig)) => tcx.dcx().fatal(format!(
             "attempt to declare `{name}` with signature {new_sig:?}, \
              but it was already declared with signature {prev_sig:?}"
         )),
@@ -181,7 +181,7 @@ fn make_local_place<'tcx>(
     is_ssa: bool,
 ) -> CPlace<'tcx> {
     if layout.is_unsized() {
-        fx.tcx.sess.span_fatal(
+        fx.tcx.dcx().span_fatal(
             fx.mir.local_decls[local].source_info.span,
             "unsized locals are not yet supported",
         );
@@ -226,7 +226,7 @@ pub(crate) fn codegen_fn_prelude<'tcx>(fx: &mut FunctionCx<'_, '_, 'tcx>, start_
 
     // FIXME implement variadics in cranelift
     if fn_abi.c_variadic {
-        fx.tcx.sess.span_fatal(
+        fx.tcx.dcx().span_fatal(
             fx.mir.span,
             "Defining variadic functions is not yet supported by Cranelift",
         );
@@ -543,7 +543,7 @@ pub(crate) fn codegen_terminator_call<'tcx>(
         // FIXME find a cleaner way to support varargs
         if fn_sig.c_variadic() {
             if !matches!(fn_sig.abi(), Abi::C { .. }) {
-                fx.tcx.sess.span_fatal(
+                fx.tcx.dcx().span_fatal(
                     source_info.span,
                     format!("Variadic call for non-C abi {:?}", fn_sig.abi()),
                 );
@@ -555,7 +555,7 @@ pub(crate) fn codegen_terminator_call<'tcx>(
                     let ty = fx.bcx.func.dfg.value_type(arg);
                     if !ty.is_int() {
                         // FIXME set %al to upperbound on float args once floats are supported
-                        fx.tcx.sess.span_fatal(
+                        fx.tcx.dcx().span_fatal(
                             source_info.span,
                             format!("Non int ty {:?} for variadic call", ty),
                         );
diff --git a/compiler/rustc_codegen_cranelift/src/base.rs b/compiler/rustc_codegen_cranelift/src/base.rs
index 8d3be19839e..881c0c0b56b 100644
--- a/compiler/rustc_codegen_cranelift/src/base.rs
+++ b/compiler/rustc_codegen_cranelift/src/base.rs
@@ -236,13 +236,13 @@ pub(crate) fn verify_func(
         match cranelift_codegen::verify_function(&func, &flags) {
             Ok(_) => {}
             Err(err) => {
-                tcx.sess.err(format!("{:?}", err));
+                tcx.dcx().err(format!("{:?}", err));
                 let pretty_error = cranelift_codegen::print_errors::pretty_verifier_error(
                     &func,
                     Some(Box::new(writer)),
                     err,
                 );
-                tcx.sess.fatal(format!("cranelift verify error:\n{}", pretty_error));
+                tcx.dcx().fatal(format!("cranelift verify error:\n{}", pretty_error));
             }
         }
     });
@@ -450,7 +450,7 @@ fn codegen_fn_body(fx: &mut FunctionCx<'_, '_, '_>, start_block: Block) {
                 unwind: _,
             } => {
                 if options.contains(InlineAsmOptions::MAY_UNWIND) {
-                    fx.tcx.sess.span_fatal(
+                    fx.tcx.dcx().span_fatal(
                         source_info.span,
                         "cranelift doesn't support unwinding from inline assembly.",
                     );
@@ -812,7 +812,7 @@ fn codegen_stmt<'tcx>(
         | StatementKind::PlaceMention(..)
         | StatementKind::AscribeUserType(..) => {}
 
-        StatementKind::Coverage { .. } => fx.tcx.sess.fatal("-Zcoverage is unimplemented"),
+        StatementKind::Coverage { .. } => fx.tcx.dcx().fatal("-Zcoverage is unimplemented"),
         StatementKind::Intrinsic(ref intrinsic) => match &**intrinsic {
             // We ignore `assume` intrinsics, they are only useful for optimizations
             NonDivergingIntrinsic::Assume(_) => {}
diff --git a/compiler/rustc_codegen_cranelift/src/common.rs b/compiler/rustc_codegen_cranelift/src/common.rs
index bd19a7ed059..1e37825b548 100644
--- a/compiler/rustc_codegen_cranelift/src/common.rs
+++ b/compiler/rustc_codegen_cranelift/src/common.rs
@@ -465,9 +465,12 @@ impl<'tcx> LayoutOfHelpers<'tcx> for RevealAllLayoutCx<'tcx> {
     #[inline]
     fn handle_layout_err(&self, err: LayoutError<'tcx>, span: Span, ty: Ty<'tcx>) -> ! {
         if let LayoutError::SizeOverflow(_) | LayoutError::ReferencesError(_) = err {
-            self.0.sess.span_fatal(span, err.to_string())
+            self.0.sess.dcx().span_fatal(span, err.to_string())
         } else {
-            self.0.sess.span_fatal(span, format!("failed to get layout for `{}`: {}", ty, err))
+            self.0
+                .sess
+                .dcx()
+                .span_fatal(span, format!("failed to get layout for `{}`: {}", ty, err))
         }
     }
 }
@@ -483,7 +486,7 @@ impl<'tcx> FnAbiOfHelpers<'tcx> for RevealAllLayoutCx<'tcx> {
         fn_abi_request: FnAbiRequest<'tcx>,
     ) -> ! {
         if let FnAbiError::Layout(LayoutError::SizeOverflow(_)) = err {
-            self.0.sess.emit_fatal(Spanned { span, node: err })
+            self.0.sess.dcx().emit_fatal(Spanned { span, node: err })
         } else {
             match fn_abi_request {
                 FnAbiRequest::OfFnPtr { sig, extra_args } => {
diff --git a/compiler/rustc_codegen_cranelift/src/constant.rs b/compiler/rustc_codegen_cranelift/src/constant.rs
index 9ffa006e59b..b6de688130c 100644
--- a/compiler/rustc_codegen_cranelift/src/constant.rs
+++ b/compiler/rustc_codegen_cranelift/src/constant.rs
@@ -263,7 +263,7 @@ fn data_id_for_static(
             attrs.flags.contains(CodegenFnAttrFlags::THREAD_LOCAL),
         ) {
             Ok(data_id) => data_id,
-            Err(ModuleError::IncompatibleDeclaration(_)) => tcx.sess.fatal(format!(
+            Err(ModuleError::IncompatibleDeclaration(_)) => tcx.dcx().fatal(format!(
                 "attempt to declare `{symbol_name}` as static, but it was already declared as function"
             )),
             Err(err) => Err::<_, _>(err).unwrap(),
@@ -311,7 +311,7 @@ fn data_id_for_static(
         attrs.flags.contains(CodegenFnAttrFlags::THREAD_LOCAL),
     ) {
         Ok(data_id) => data_id,
-        Err(ModuleError::IncompatibleDeclaration(_)) => tcx.sess.fatal(format!(
+        Err(ModuleError::IncompatibleDeclaration(_)) => tcx.dcx().fatal(format!(
             "attempt to declare `{symbol_name}` as static, but it was already declared as function"
         )),
         Err(err) => Err::<_, _>(err).unwrap(),
@@ -360,7 +360,7 @@ fn define_all_allocs(tcx: TyCtxt<'_>, module: &mut dyn Module, cx: &mut Constant
                 if let Some(names) = section_name.split_once(',') {
                     names
                 } else {
-                    tcx.sess.fatal(format!(
+                    tcx.dcx().fatal(format!(
                         "#[link_section = \"{}\"] is not valid for macos target: must be segment and section separated by comma",
                         section_name
                     ));
@@ -406,7 +406,7 @@ fn define_all_allocs(tcx: TyCtxt<'_>, module: &mut dyn Module, cx: &mut Constant
                 GlobalAlloc::Static(def_id) => {
                     if tcx.codegen_fn_attrs(def_id).flags.contains(CodegenFnAttrFlags::THREAD_LOCAL)
                     {
-                        tcx.sess.fatal(format!(
+                        tcx.dcx().fatal(format!(
                             "Allocation {:?} contains reference to TLS value {:?}",
                             alloc_id, def_id
                         ));
diff --git a/compiler/rustc_codegen_cranelift/src/driver/aot.rs b/compiler/rustc_codegen_cranelift/src/driver/aot.rs
index b3ab533df3d..e77b0cd0721 100644
--- a/compiler/rustc_codegen_cranelift/src/driver/aot.rs
+++ b/compiler/rustc_codegen_cranelift/src/driver/aot.rs
@@ -69,7 +69,7 @@ impl OngoingCodegen {
 
             let module_codegen_result = match module_codegen_result {
                 Ok(module_codegen_result) => module_codegen_result,
-                Err(err) => sess.fatal(err),
+                Err(err) => sess.dcx().fatal(err),
             };
             let ModuleCodegenResult { module_regular, module_global_asm, existing_work_product } =
                 module_codegen_result;
@@ -108,7 +108,7 @@ impl OngoingCodegen {
 
         self.concurrency_limiter.finished();
 
-        sess.abort_if_errors();
+        sess.dcx().abort_if_errors();
 
         (
             CodegenResults {
@@ -422,7 +422,7 @@ pub(crate) fn run_aot(
                                     backend_config.clone(),
                                     global_asm_config.clone(),
                                     cgu.name(),
-                                    concurrency_limiter.acquire(tcx.sess.dcx()),
+                                    concurrency_limiter.acquire(tcx.dcx()),
                                 ),
                                 module_codegen,
                                 Some(rustc_middle::dep_graph::hash_result),
@@ -455,7 +455,7 @@ pub(crate) fn run_aot(
             "allocator_shim".to_owned(),
         ) {
             Ok(allocator_module) => Some(allocator_module),
-            Err(err) => tcx.sess.fatal(err),
+            Err(err) => tcx.dcx().fatal(err),
         }
     } else {
         None
@@ -478,7 +478,7 @@ pub(crate) fn run_aot(
             let obj = create_compressed_metadata_file(tcx.sess, &metadata, &symbol_name);
 
             if let Err(err) = std::fs::write(&tmp_file, obj) {
-                tcx.sess.fatal(format!("error writing metadata object file: {}", err));
+                tcx.dcx().fatal(format!("error writing metadata object file: {}", err));
             }
 
             (metadata_cgu_name, tmp_file)
diff --git a/compiler/rustc_codegen_cranelift/src/driver/jit.rs b/compiler/rustc_codegen_cranelift/src/driver/jit.rs
index 6ee65d12c73..7905ec8402d 100644
--- a/compiler/rustc_codegen_cranelift/src/driver/jit.rs
+++ b/compiler/rustc_codegen_cranelift/src/driver/jit.rs
@@ -94,11 +94,11 @@ fn create_jit_module(
 
 pub(crate) fn run_jit(tcx: TyCtxt<'_>, backend_config: BackendConfig) -> ! {
     if !tcx.sess.opts.output_types.should_codegen() {
-        tcx.sess.fatal("JIT mode doesn't work with `cargo check`");
+        tcx.dcx().fatal("JIT mode doesn't work with `cargo check`");
     }
 
     if !tcx.crate_types().contains(&rustc_session::config::CrateType::Executable) {
-        tcx.sess.fatal("can't jit non-executable crate");
+        tcx.dcx().fatal("can't jit non-executable crate");
     }
 
     let (mut jit_module, mut cx) = create_jit_module(
@@ -141,17 +141,17 @@ pub(crate) fn run_jit(tcx: TyCtxt<'_>, backend_config: BackendConfig) -> ! {
                 }
                 MonoItem::GlobalAsm(item_id) => {
                     let item = tcx.hir().item(item_id);
-                    tcx.sess.span_fatal(item.span, "Global asm is not supported in JIT mode");
+                    tcx.dcx().span_fatal(item.span, "Global asm is not supported in JIT mode");
                 }
             }
         }
     });
 
     if !cx.global_asm.is_empty() {
-        tcx.sess.fatal("Inline asm is not supported in JIT mode");
+        tcx.dcx().fatal("Inline asm is not supported in JIT mode");
     }
 
-    tcx.sess.abort_if_errors();
+    tcx.dcx().abort_if_errors();
 
     jit_module.finalize_definitions().unwrap();
     unsafe { cx.unwind_context.register_jit(&jit_module) };
@@ -338,7 +338,7 @@ fn dep_symbol_lookup_fn(
             .collect::<Box<[_]>>(),
     );
 
-    sess.abort_if_errors();
+    sess.dcx().abort_if_errors();
 
     Box::new(move |sym_name| {
         for dylib in &*imported_dylibs {
diff --git a/compiler/rustc_codegen_cranelift/src/global_asm.rs b/compiler/rustc_codegen_cranelift/src/global_asm.rs
index b14007f4e52..af99239d815 100644
--- a/compiler/rustc_codegen_cranelift/src/global_asm.rs
+++ b/compiler/rustc_codegen_cranelift/src/global_asm.rs
@@ -47,7 +47,7 @@ pub(crate) fn codegen_global_asm_item(tcx: TyCtxt<'_>, global_asm: &mut String,
                         }
                         InlineAsmOperand::SymFn { anon_const } => {
                             if cfg!(not(feature = "inline_asm_sym")) {
-                                tcx.sess.span_err(
+                                tcx.dcx().span_err(
                                     item.span,
                                     "asm! and global_asm! sym operands are not yet supported",
                                 );
@@ -65,7 +65,7 @@ pub(crate) fn codegen_global_asm_item(tcx: TyCtxt<'_>, global_asm: &mut String,
                         }
                         InlineAsmOperand::SymStatic { path: _, def_id } => {
                             if cfg!(not(feature = "inline_asm_sym")) {
-                                tcx.sess.span_err(
+                                tcx.dcx().span_err(
                                     item.span,
                                     "asm! and global_asm! sym operands are not yet supported",
                                 );
diff --git a/compiler/rustc_codegen_cranelift/src/inline_asm.rs b/compiler/rustc_codegen_cranelift/src/inline_asm.rs
index 73f4bc7c151..6b9cec39d70 100644
--- a/compiler/rustc_codegen_cranelift/src/inline_asm.rs
+++ b/compiler/rustc_codegen_cranelift/src/inline_asm.rs
@@ -84,7 +84,7 @@ pub(crate) fn codegen_inline_asm_terminator<'tcx>(
             InlineAsmOperand::SymFn { ref value } => {
                 if cfg!(not(feature = "inline_asm_sym")) {
                     fx.tcx
-                        .sess
+                        .dcx()
                         .span_err(span, "asm! and global_asm! sym operands are not yet supported");
                 }
 
@@ -455,7 +455,7 @@ impl<'tcx> InlineAssemblyGenerator<'_, 'tcx> {
             }
             _ => self
                 .tcx
-                .sess
+                .dcx()
                 .fatal(format!("Unsupported binary format for inline asm: {binary_format:?}")),
         }
 
@@ -563,7 +563,7 @@ impl<'tcx> InlineAssemblyGenerator<'_, 'tcx> {
             BinaryFormat::Macho | BinaryFormat::Coff => {}
             _ => self
                 .tcx
-                .sess
+                .dcx()
                 .fatal(format!("Unsupported binary format for inline asm: {binary_format:?}")),
         }
 
diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm.rs
index dbd5db87511..a38a728c926 100644
--- a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm.rs
+++ b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm.rs
@@ -68,7 +68,7 @@ pub(crate) fn codegen_llvm_intrinsic_call<'tcx>(
 
         _ => {
             fx.tcx
-                .sess
+                .dcx()
                 .warn(format!("unsupported llvm intrinsic {}; replacing with trap", intrinsic));
             crate::trap::trap_unimplemented(fx, intrinsic);
             return;
diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_aarch64.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_aarch64.rs
index e1e514dca44..c8f9c3997a6 100644
--- a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_aarch64.rs
+++ b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_aarch64.rs
@@ -309,7 +309,7 @@ pub(crate) fn codegen_aarch64_llvm_intrinsic_call<'tcx>(
         }
         */
         _ => {
-            fx.tcx.sess.warn(format!(
+            fx.tcx.dcx().warn(format!(
                 "unsupported AArch64 llvm intrinsic {}; replacing with trap",
                 intrinsic
             ));
diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_x86.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_x86.rs
index 99bb5c4eae2..81114cbf40d 100644
--- a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_x86.rs
+++ b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_x86.rs
@@ -960,7 +960,9 @@ pub(crate) fn codegen_x86_llvm_intrinsic_call<'tcx>(
             {
                 imm8
             } else {
-                fx.tcx.sess.span_fatal(span, "Index argument for `_mm_cmpestri` is not a constant");
+                fx.tcx
+                    .dcx()
+                    .span_fatal(span, "Index argument for `_mm_cmpestri` is not a constant");
             };
 
             let imm8 = imm8.try_to_u8().unwrap_or_else(|_| panic!("kind not scalar: {:?}", imm8));
@@ -1011,7 +1013,9 @@ pub(crate) fn codegen_x86_llvm_intrinsic_call<'tcx>(
             {
                 imm8
             } else {
-                fx.tcx.sess.span_fatal(span, "Index argument for `_mm_cmpestrm` is not a constant");
+                fx.tcx
+                    .dcx()
+                    .span_fatal(span, "Index argument for `_mm_cmpestrm` is not a constant");
             };
 
             let imm8 = imm8.try_to_u8().unwrap_or_else(|_| panic!("kind not scalar: {:?}", imm8));
@@ -1056,7 +1060,7 @@ pub(crate) fn codegen_x86_llvm_intrinsic_call<'tcx>(
             {
                 imm8
             } else {
-                fx.tcx.sess.span_fatal(
+                fx.tcx.dcx().span_fatal(
                     span,
                     "Index argument for `_mm_clmulepi64_si128` is not a constant",
                 );
@@ -1093,7 +1097,7 @@ pub(crate) fn codegen_x86_llvm_intrinsic_call<'tcx>(
             {
                 imm8
             } else {
-                fx.tcx.sess.span_fatal(
+                fx.tcx.dcx().span_fatal(
                     span,
                     "Index argument for `_mm_aeskeygenassist_si128` is not a constant",
                 );
@@ -1361,7 +1365,7 @@ pub(crate) fn codegen_x86_llvm_intrinsic_call<'tcx>(
 
         _ => {
             fx.tcx
-                .sess
+                .dcx()
                 .warn(format!("unsupported x86 llvm intrinsic {}; replacing with trap", intrinsic));
             crate::trap::trap_unimplemented(fx, intrinsic);
             return;
diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs
index 68126f12424..15249402a63 100644
--- a/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs
+++ b/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs
@@ -37,7 +37,7 @@ fn report_atomic_type_validation_error<'tcx>(
     span: Span,
     ty: Ty<'tcx>,
 ) {
-    fx.tcx.sess.span_err(
+    fx.tcx.dcx().span_err(
         span,
         format!(
             "`{}` intrinsic: expected basic integer or raw pointer type, found `{:?}`",
@@ -785,7 +785,7 @@ fn codegen_regular_intrinsic_call<'tcx>(
                         return;
                     } else {
                         fx.tcx
-                            .sess
+                            .dcx()
                             .span_fatal(source_info.span, "128bit atomics not yet supported");
                     }
                 }
@@ -816,7 +816,7 @@ fn codegen_regular_intrinsic_call<'tcx>(
                         return;
                     } else {
                         fx.tcx
-                            .sess
+                            .dcx()
                             .span_fatal(source_info.span, "128bit atomics not yet supported");
                     }
                 }
@@ -1245,7 +1245,7 @@ fn codegen_regular_intrinsic_call<'tcx>(
 
         // FIXME implement variadics in cranelift
         sym::va_copy | sym::va_arg | sym::va_end => {
-            fx.tcx.sess.span_fatal(
+            fx.tcx.dcx().span_fatal(
                 source_info.span,
                 "Defining variadic functions is not yet supported by Cranelift",
             );
@@ -1253,7 +1253,7 @@ fn codegen_regular_intrinsic_call<'tcx>(
 
         _ => {
             fx.tcx
-                .sess
+                .dcx()
                 .span_fatal(source_info.span, format!("unsupported intrinsic {}", intrinsic));
         }
     }
diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/simd.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/simd.rs
index d06237f8d91..78ea7c2dbfc 100644
--- a/compiler/rustc_codegen_cranelift/src/intrinsics/simd.rs
+++ b/compiler/rustc_codegen_cranelift/src/intrinsics/simd.rs
@@ -12,7 +12,7 @@ fn report_simd_type_validation_error(
     span: Span,
     ty: Ty<'_>,
 ) {
-    fx.tcx.sess.span_err(span, format!("invalid monomorphization of `{}` intrinsic: expected SIMD input type, found non-SIMD `{}`", intrinsic, ty));
+    fx.tcx.dcx().span_err(span, format!("invalid monomorphization of `{}` intrinsic: expected SIMD input type, found non-SIMD `{}`", intrinsic, ty));
     // Prevent verifier error
     fx.bcx.ins().trap(TrapCode::UnreachableCodeReached);
 }
@@ -192,7 +192,7 @@ pub(super) fn codegen_simd_intrinsic_call<'tcx>(
                     .try_into()
                     .unwrap(),
                 _ => {
-                    fx.tcx.sess.span_err(
+                    fx.tcx.dcx().span_err(
                         span,
                         format!("simd_shuffle index must be an array of `u32`, got `{}`", idx_ty),
                     );
@@ -278,7 +278,7 @@ pub(super) fn codegen_simd_intrinsic_call<'tcx>(
             {
                 idx_const
             } else {
-                fx.tcx.sess.span_fatal(span, "Index argument for `simd_insert` is not a constant");
+                fx.tcx.dcx().span_fatal(span, "Index argument for `simd_insert` is not a constant");
             };
 
             let idx: u32 = idx_const
@@ -286,7 +286,7 @@ pub(super) fn codegen_simd_intrinsic_call<'tcx>(
                 .unwrap_or_else(|_| panic!("kind not scalar: {:?}", idx_const));
             let (lane_count, _lane_ty) = base.layout().ty.simd_size_and_type(fx.tcx);
             if u64::from(idx) >= lane_count {
-                fx.tcx.sess.span_fatal(
+                fx.tcx.dcx().span_fatal(
                     fx.mir.span,
                     format!("[simd_insert] idx {} >= lane_count {}", idx, lane_count),
                 );
@@ -316,7 +316,7 @@ pub(super) fn codegen_simd_intrinsic_call<'tcx>(
             {
                 idx_const
             } else {
-                fx.tcx.sess.span_warn(span, "Index argument for `simd_extract` is not a constant");
+                fx.tcx.dcx().span_warn(span, "Index argument for `simd_extract` is not a constant");
                 let trap_block = fx.bcx.create_block();
                 let true_ = fx.bcx.ins().iconst(types::I8, 1);
                 let ret_block = fx.get_block(target);
@@ -334,7 +334,7 @@ pub(super) fn codegen_simd_intrinsic_call<'tcx>(
                 .unwrap_or_else(|_| panic!("kind not scalar: {:?}", idx_const));
             let (lane_count, _lane_ty) = v.layout().ty.simd_size_and_type(fx.tcx);
             if u64::from(idx) >= lane_count {
-                fx.tcx.sess.span_fatal(
+                fx.tcx.dcx().span_fatal(
                     fx.mir.span,
                     format!("[simd_extract] idx {} >= lane_count {}", idx, lane_count),
                 );
@@ -859,7 +859,7 @@ pub(super) fn codegen_simd_intrinsic_call<'tcx>(
             match lane_ty.kind() {
                 ty::Int(_) | ty::Uint(_) => {}
                 _ => {
-                    fx.tcx.sess.span_fatal(
+                    fx.tcx.dcx().span_fatal(
                         span,
                         format!(
                             "invalid monomorphization of `simd_bitmask` intrinsic: \
@@ -899,7 +899,7 @@ pub(super) fn codegen_simd_intrinsic_call<'tcx>(
                         && len.try_eval_target_usize(fx.tcx, ty::ParamEnv::reveal_all())
                             == Some(expected_bytes) => {}
                 _ => {
-                    fx.tcx.sess.span_fatal(
+                    fx.tcx.dcx().span_fatal(
                         span,
                         format!(
                             "invalid monomorphization of `simd_bitmask` intrinsic: \
@@ -1117,7 +1117,7 @@ pub(super) fn codegen_simd_intrinsic_call<'tcx>(
         }
 
         _ => {
-            fx.tcx.sess.span_err(span, format!("Unknown SIMD intrinsic {}", intrinsic));
+            fx.tcx.dcx().span_err(span, format!("Unknown SIMD intrinsic {}", intrinsic));
             // Prevent verifier error
             fx.bcx.ins().trap(TrapCode::UnreachableCodeReached);
             return;
diff --git a/compiler/rustc_codegen_cranelift/src/lib.rs b/compiler/rustc_codegen_cranelift/src/lib.rs
index d0ce209be44..b482f0dd2f0 100644
--- a/compiler/rustc_codegen_cranelift/src/lib.rs
+++ b/compiler/rustc_codegen_cranelift/src/lib.rs
@@ -177,13 +177,15 @@ impl CodegenBackend for CraneliftCodegenBackend {
         use rustc_session::config::Lto;
         match sess.lto() {
             Lto::No | Lto::ThinLocal => {}
-            Lto::Thin | Lto::Fat => sess.warn("LTO is not supported. You may get a linker error."),
+            Lto::Thin | Lto::Fat => {
+                sess.dcx().warn("LTO is not supported. You may get a linker error.")
+            }
         }
 
         let mut config = self.config.borrow_mut();
         if config.is_none() {
             let new_config = BackendConfig::from_opts(&sess.opts.cg.llvm_args)
-                .unwrap_or_else(|err| sess.fatal(err));
+                .unwrap_or_else(|err| sess.dcx().fatal(err));
             *config = Some(new_config);
         }
     }
@@ -202,7 +204,7 @@ impl CodegenBackend for CraneliftCodegenBackend {
         metadata: EncodedMetadata,
         need_metadata_module: bool,
     ) -> Box<dyn Any> {
-        tcx.sess.abort_if_errors();
+        tcx.dcx().abort_if_errors();
         let config = self.config.borrow().clone().unwrap();
         match config.codegen_mode {
             CodegenMode::Aot => driver::aot::run_aot(tcx, config, metadata, need_metadata_module),
@@ -211,7 +213,7 @@ impl CodegenBackend for CraneliftCodegenBackend {
                 driver::jit::run_jit(tcx, config);
 
                 #[cfg(not(feature = "jit"))]
-                tcx.sess.fatal("jit support was disabled when compiling rustc_codegen_cranelift");
+                tcx.dcx().fatal("jit support was disabled when compiling rustc_codegen_cranelift");
             }
         }
     }
@@ -243,7 +245,7 @@ impl CodegenBackend for CraneliftCodegenBackend {
 fn target_triple(sess: &Session) -> target_lexicon::Triple {
     match sess.target.llvm_target.parse() {
         Ok(triple) => triple,
-        Err(err) => sess.fatal(format!("target not recognized: {}", err)),
+        Err(err) => sess.dcx().fatal(format!("target not recognized: {}", err)),
     }
 }
 
@@ -310,17 +312,18 @@ fn build_isa(sess: &Session, backend_config: &BackendConfig) -> Arc<dyn isa::Tar
         Some(value) => {
             let mut builder =
                 cranelift_codegen::isa::lookup(target_triple.clone()).unwrap_or_else(|err| {
-                    sess.fatal(format!("can't compile for {}: {}", target_triple, err));
+                    sess.dcx().fatal(format!("can't compile for {}: {}", target_triple, err));
                 });
             if let Err(_) = builder.enable(value) {
-                sess.fatal("the specified target cpu isn't currently supported by Cranelift.");
+                sess.dcx()
+                    .fatal("the specified target cpu isn't currently supported by Cranelift.");
             }
             builder
         }
         None => {
             let mut builder =
                 cranelift_codegen::isa::lookup(target_triple.clone()).unwrap_or_else(|err| {
-                    sess.fatal(format!("can't compile for {}: {}", target_triple, err));
+                    sess.dcx().fatal(format!("can't compile for {}: {}", target_triple, err));
                 });
             if target_triple.architecture == target_lexicon::Architecture::X86_64 {
                 // Don't use "haswell" as the default, as it implies `has_lzcnt`.
@@ -333,7 +336,7 @@ fn build_isa(sess: &Session, backend_config: &BackendConfig) -> Arc<dyn isa::Tar
 
     match isa_builder.finish(flags) {
         Ok(target_isa) => target_isa,
-        Err(err) => sess.fatal(format!("failed to build TargetIsa: {}", err)),
+        Err(err) => sess.dcx().fatal(format!("failed to build TargetIsa: {}", err)),
     }
 }
 
diff --git a/compiler/rustc_codegen_cranelift/src/main_shim.rs b/compiler/rustc_codegen_cranelift/src/main_shim.rs
index b5efe44d8b3..6535c3a367b 100644
--- a/compiler/rustc_codegen_cranelift/src/main_shim.rs
+++ b/compiler/rustc_codegen_cranelift/src/main_shim.rs
@@ -74,7 +74,7 @@ pub(crate) fn maybe_create_entry_wrapper(
         let cmain_func_id = match m.declare_function(entry_name, Linkage::Export, &cmain_sig) {
             Ok(func_id) => func_id,
             Err(err) => {
-                tcx.sess
+                tcx.dcx()
                     .fatal(format!("entry symbol `{entry_name}` declared multiple times: {err}"));
             }
         };
@@ -171,7 +171,7 @@ pub(crate) fn maybe_create_entry_wrapper(
         }
 
         if let Err(err) = m.define_function(cmain_func_id, &mut ctx) {
-            tcx.sess.fatal(format!("entry symbol `{entry_name}` defined multiple times: {err}"));
+            tcx.dcx().fatal(format!("entry symbol `{entry_name}` defined multiple times: {err}"));
         }
 
         unwind_context.add_function(cmain_func_id, &ctx, m.isa());
diff --git a/compiler/rustc_codegen_cranelift/src/value_and_place.rs b/compiler/rustc_codegen_cranelift/src/value_and_place.rs
index 567a5669d49..838c73fa213 100644
--- a/compiler/rustc_codegen_cranelift/src/value_and_place.rs
+++ b/compiler/rustc_codegen_cranelift/src/value_and_place.rs
@@ -397,7 +397,7 @@ impl<'tcx> CPlace<'tcx> {
 
         if layout.size.bytes() >= u64::from(u32::MAX - 16) {
             fx.tcx
-                .sess
+                .dcx()
                 .fatal(format!("values of type {} are too big to store on the stack", layout.ty));
         }