rust-lang · matthiaskrgr · May 21, 2025 · May 10, 2025 · Apr 22, 2025 · May 23, 2025
diff --git a/Cargo.lock b/Cargo.lock
@@ -4673,6 +4673,7 @@ dependencies = [
  "bincode",
  "rustc-hash 2.1.1",
  "serde",
+ "serde_derive",
  "serde_json",
 ]
 

diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs
@@ -732,7 +732,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         span: Span,
         args: Option<&'hir hir::GenericArgs<'hir>>,
     ) -> &'hir hir::Path<'hir> {
-        let def_id = self.tcx.require_lang_item(lang_item, Some(span));
+        let def_id = self.tcx.require_lang_item(lang_item, span);
         let def_kind = self.tcx.def_kind(def_id);
         let res = Res::Def(def_kind, def_id);
         self.arena.alloc(hir::Path {

diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
@@ -263,7 +263,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
                 // something that already has `Fn`-like bounds (or is a closure), so we can't
                 // restrict anyways.
             } else {
-                let copy_did = self.infcx.tcx.require_lang_item(LangItem::Copy, Some(span));
+                let copy_did = self.infcx.tcx.require_lang_item(LangItem::Copy, span);
                 self.suggest_adding_bounds(&mut err, ty, copy_did, span);
             }
 
@@ -1915,7 +1915,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
 
         let local_ty = self.body.local_decls[place.local].ty;
         let typeck_results = tcx.typeck(self.mir_def_id());
-        let clone = tcx.require_lang_item(LangItem::Clone, Some(body.span));
+        let clone = tcx.require_lang_item(LangItem::Clone, body.span);
         for expr in expr_finder.clones {
             if let hir::ExprKind::MethodCall(_, rcvr, _, span) = expr.kind
                 && let Some(rcvr_ty) = typeck_results.node_type_opt(rcvr.hir_id)

diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs
@@ -688,7 +688,7 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
                 if !self.unsized_feature_enabled() {
                     let trait_ref = ty::TraitRef::new(
                         tcx,
-                        tcx.require_lang_item(LangItem::Sized, Some(self.last_span)),
+                        tcx.require_lang_item(LangItem::Sized, self.last_span),
                         [place_ty],
                     );
                     self.prove_trait_ref(
@@ -1010,7 +1010,7 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
                             let ty = place.ty(self.body, tcx).ty;
                             let trait_ref = ty::TraitRef::new(
                                 tcx,
-                                tcx.require_lang_item(LangItem::Copy, Some(span)),
+                                tcx.require_lang_item(LangItem::Copy, span),
                                 [ty],
                             );
 
@@ -1025,11 +1025,8 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
             }
 
             &Rvalue::NullaryOp(NullOp::SizeOf | NullOp::AlignOf, ty) => {
-                let trait_ref = ty::TraitRef::new(
-                    tcx,
-                    tcx.require_lang_item(LangItem::Sized, Some(span)),
-                    [ty],
-                );
+                let trait_ref =
+                    ty::TraitRef::new(tcx, tcx.require_lang_item(LangItem::Sized, span), [ty]);
 
                 self.prove_trait_ref(
                     trait_ref,
@@ -1041,11 +1038,8 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
             &Rvalue::NullaryOp(NullOp::UbChecks, _) => {}
 
             Rvalue::ShallowInitBox(_operand, ty) => {
-                let trait_ref = ty::TraitRef::new(
-                    tcx,
-                    tcx.require_lang_item(LangItem::Sized, Some(span)),
-                    [*ty],
-                );
+                let trait_ref =
+                    ty::TraitRef::new(tcx, tcx.require_lang_item(LangItem::Sized, span), [*ty]);
 
                 self.prove_trait_ref(
                     trait_ref,
@@ -1222,7 +1216,7 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
                         let &ty = ty;
                         let trait_ref = ty::TraitRef::new(
                             tcx,
-                            tcx.require_lang_item(LangItem::CoerceUnsized, Some(span)),
+                            tcx.require_lang_item(LangItem::CoerceUnsized, span),
                             [op.ty(self.body, tcx), ty],
                         );
 
@@ -1811,7 +1805,7 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
         if let PlaceContext::NonMutatingUse(NonMutatingUseContext::Copy) = context {
             let trait_ref = ty::TraitRef::new(
                 tcx,
-                tcx.require_lang_item(LangItem::Copy, Some(self.last_span)),
+                tcx.require_lang_item(LangItem::Copy, self.last_span),
                 [place_ty.ty],
             );
 

diff --git a/compiler/rustc_borrowck/src/universal_regions.rs b/compiler/rustc_borrowck/src/universal_regions.rs
@@ -544,10 +544,10 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
         // (as it's created inside the body itself, not passed in from outside).
         if let DefiningTy::FnDef(def_id, _) = defining_ty {
             if self.infcx.tcx.fn_sig(def_id).skip_binder().c_variadic() {
-                let va_list_did = self.infcx.tcx.require_lang_item(
-                    LangItem::VaList,
-                    Some(self.infcx.tcx.def_span(self.mir_def)),
-                );
+                let va_list_did = self
+                    .infcx
+                    .tcx
+                    .require_lang_item(LangItem::VaList, self.infcx.tcx.def_span(self.mir_def));
 
                 let reg_vid = self
                     .infcx

diff --git a/compiler/rustc_codegen_cranelift/src/base.rs b/compiler/rustc_codegen_cranelift/src/base.rs
@@ -380,7 +380,7 @@ fn codegen_fn_body(fx: &mut FunctionCx<'_, '_, '_>, start_block: Block) {
                             rustc_hir::LangItem::PanicBoundsCheck,
                             &[index, len, location],
                             *unwind,
-                            Some(source_info.span),
+                            source_info.span,
                         );
                     }
                     AssertKind::MisalignedPointerDereference { ref required, ref found } => {
@@ -393,7 +393,7 @@ fn codegen_fn_body(fx: &mut FunctionCx<'_, '_, '_>, start_block: Block) {
                             rustc_hir::LangItem::PanicMisalignedPointerDereference,
                             &[required, found, location],
                             *unwind,
-                            Some(source_info.span),
+                            source_info.span,
                         );
                     }
                     AssertKind::NullPointerDereference => {
@@ -404,7 +404,7 @@ fn codegen_fn_body(fx: &mut FunctionCx<'_, '_, '_>, start_block: Block) {
                             rustc_hir::LangItem::PanicNullPointerDereference,
                             &[location],
                             *unwind,
-                            Some(source_info.span),
+                            source_info.span,
                         )
                     }
                     _ => {
@@ -415,7 +415,7 @@ fn codegen_fn_body(fx: &mut FunctionCx<'_, '_, '_>, start_block: Block) {
                             msg.panic_function(),
                             &[location],
                             *unwind,
-                            Some(source_info.span),
+                            source_info.span,
                         );
                     }
                 }
@@ -531,7 +531,7 @@ fn codegen_fn_body(fx: &mut FunctionCx<'_, '_, '_>, start_block: Block) {
                 );
             }
             TerminatorKind::UnwindTerminate(reason) => {
-                codegen_unwind_terminate(fx, Some(source_info.span), *reason);
+                codegen_unwind_terminate(fx, source_info.span, *reason);
             }
             TerminatorKind::UnwindResume => {
                 // FIXME implement unwinding
@@ -1074,7 +1074,7 @@ pub(crate) fn codegen_operand<'tcx>(
 pub(crate) fn codegen_panic_nounwind<'tcx>(
     fx: &mut FunctionCx<'_, '_, 'tcx>,
     msg_str: &str,
-    span: Option<Span>,
+    span: Span,
 ) {
     let msg_ptr = fx.anonymous_str(msg_str);
     let msg_len = fx.bcx.ins().iconst(fx.pointer_type, i64::try_from(msg_str.len()).unwrap());
@@ -1091,7 +1091,7 @@ pub(crate) fn codegen_panic_nounwind<'tcx>(
 
 pub(crate) fn codegen_unwind_terminate<'tcx>(
     fx: &mut FunctionCx<'_, '_, 'tcx>,
-    span: Option<Span>,
+    span: Span,
     reason: UnwindTerminateReason,
 ) {
     codegen_panic_inner(fx, reason.lang_item(), &[], UnwindAction::Unreachable, span);
@@ -1102,7 +1102,7 @@ fn codegen_panic_inner<'tcx>(
     lang_item: rustc_hir::LangItem,
     args: &[Value],
     _unwind: UnwindAction,
-    span: Option<Span>,
+    span: Span,
 ) {
     fx.bcx.set_cold_block(fx.bcx.current_block().unwrap());
 

diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm.rs
@@ -71,7 +71,7 @@ pub(crate) fn codegen_llvm_intrinsic_call<'tcx>(
                  See https://github.com/rust-lang/rustc_codegen_cranelift/issues/171\n\
                  Please open an issue at https://github.com/rust-lang/rustc_codegen_cranelift/issues"
             );
-            crate::base::codegen_panic_nounwind(fx, &msg, None);
+            crate::base::codegen_panic_nounwind(fx, &msg, span);
             return;
         }
     }

diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_aarch64.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_aarch64.rs
@@ -512,7 +512,7 @@ pub(super) fn codegen_aarch64_llvm_intrinsic_call<'tcx>(
                  See https://github.com/rust-lang/rustc_codegen_cranelift/issues/171\n\
                  Please open an issue at https://github.com/rust-lang/rustc_codegen_cranelift/issues"
             );
-            crate::base::codegen_panic_nounwind(fx, &msg, None);
+            crate::base::codegen_panic_nounwind(fx, &msg, fx.mir.span);
             return;
         }
     }

diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_x86.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/llvm_x86.rs
@@ -1321,7 +1321,7 @@ pub(super) fn codegen_x86_llvm_intrinsic_call<'tcx>(
                  See https://github.com/rust-lang/rustc_codegen_cranelift/issues/171\n\
                  Please open an issue at https://github.com/rust-lang/rustc_codegen_cranelift/issues"
             );
-            crate::base::codegen_panic_nounwind(fx, &msg, None);
+            crate::base::codegen_panic_nounwind(fx, &msg, span);
             return;
         }
     }

diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs
@@ -785,7 +785,7 @@ fn codegen_regular_intrinsic_call<'tcx>(
                             }
                         })
                     });
-                    crate::base::codegen_panic_nounwind(fx, &msg_str, Some(source_info.span));
+                    crate::base::codegen_panic_nounwind(fx, &msg_str, source_info.span);
                     return Ok(());
                 }
             }
@@ -884,7 +884,7 @@ fn codegen_regular_intrinsic_call<'tcx>(
                         crate::base::codegen_panic_nounwind(
                             fx,
                             "128bit atomics not yet supported",
-                            None,
+                            source_info.span,
                         );
                         return Ok(());
                     } else {
@@ -919,7 +919,7 @@ fn codegen_regular_intrinsic_call<'tcx>(
                         crate::base::codegen_panic_nounwind(
                             fx,
                             "128bit atomics not yet supported",
-                            None,
+                            source_info.span,
                         );
                         return Ok(());
                     } else {

diff --git a/compiler/rustc_codegen_cranelift/src/main_shim.rs b/compiler/rustc_codegen_cranelift/src/main_shim.rs
@@ -101,7 +101,7 @@ pub(crate) fn maybe_create_entry_wrapper(
                 let call_inst = bcx.ins().call(main_func_ref, &[]);
                 let call_results = bcx.func.dfg.inst_results(call_inst).to_owned();
 
-                let termination_trait = tcx.require_lang_item(LangItem::Termination, None);
+                let termination_trait = tcx.require_lang_item(LangItem::Termination, DUMMY_SP);
                 let report = tcx
                     .associated_items(termination_trait)
                     .find_by_ident_and_kind(
@@ -136,7 +136,7 @@ pub(crate) fn maybe_create_entry_wrapper(
                 }
             } else {
                 // Regular main fn invoked via start lang item.
-                let start_def_id = tcx.require_lang_item(LangItem::Start, None);
+                let start_def_id = tcx.require_lang_item(LangItem::Start, DUMMY_SP);
                 let start_instance = Instance::expect_resolve(
                     tcx,
                     ty::TypingEnv::fully_monomorphized(),

diff --git a/compiler/rustc_codegen_cranelift/src/num.rs b/compiler/rustc_codegen_cranelift/src/num.rs
@@ -54,7 +54,7 @@ fn codegen_three_way_compare<'tcx>(
     let gt = fx.bcx.ins().icmp(gt_cc, lhs, rhs);
     let lt = fx.bcx.ins().icmp(lt_cc, lhs, rhs);
     let val = fx.bcx.ins().isub(gt, lt);
-    CValue::by_val(val, fx.layout_of(fx.tcx.ty_ordering_enum(Some(fx.mir.span))))
+    CValue::by_val(val, fx.layout_of(fx.tcx.ty_ordering_enum(fx.mir.span)))
 }
 
 fn codegen_compare_bin_op<'tcx>(

diff --git a/compiler/rustc_codegen_cranelift/src/unsize.rs b/compiler/rustc_codegen_cranelift/src/unsize.rs
@@ -240,7 +240,7 @@ pub(crate) fn size_and_align_of<'tcx>(
                 })
             });
 
-            codegen_panic_nounwind(fx, &msg_str, None);
+            codegen_panic_nounwind(fx, &msg_str, fx.mir.span);
 
             fx.bcx.switch_to_block(next_block);
 

diff --git a/compiler/rustc_codegen_ssa/src/base.rs b/compiler/rustc_codegen_ssa/src/base.rs
@@ -561,7 +561,7 @@ pub fn maybe_create_entry_wrapper<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
 
         let EntryFnType::Main { sigpipe } = entry_type;
         let (start_fn, start_ty, args, instance) = {
-            let start_def_id = cx.tcx().require_lang_item(LangItem::Start, None);
+            let start_def_id = cx.tcx().require_lang_item(LangItem::Start, DUMMY_SP);
             let start_instance = ty::Instance::expect_resolve(
                 cx.tcx(),
                 cx.typing_env(),

diff --git a/compiler/rustc_codegen_ssa/src/common.rs b/compiler/rustc_codegen_ssa/src/common.rs
@@ -110,7 +110,7 @@ mod temp_stable_hash_impls {
 
 pub(crate) fn build_langcall<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     bx: &Bx,
-    span: Option<Span>,
+    span: Span,
     li: LangItem,
 ) -> (Bx::FnAbiOfResult, Bx::Value, Instance<'tcx>) {
     let tcx = bx.tcx();

diff --git a/compiler/rustc_codegen_ssa/src/mir/block.rs b/compiler/rustc_codegen_ssa/src/mir/block.rs
@@ -783,7 +783,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             }
         };
 
-        let (fn_abi, llfn, instance) = common::build_langcall(bx, Some(span), lang_item);
+        let (fn_abi, llfn, instance) = common::build_langcall(bx, span, lang_item);
 
         // Codegen the actual panic invoke/call.
         let merging_succ =
@@ -803,7 +803,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         self.set_debug_loc(bx, terminator.source_info);
 
         // Obtain the panic entry point.
-        let (fn_abi, llfn, instance) = common::build_langcall(bx, Some(span), reason.lang_item());
+        let (fn_abi, llfn, instance) = common::build_langcall(bx, span, reason.lang_item());
 
         // Codegen the actual panic invoke/call.
         let merging_succ = helper.do_call(
@@ -871,7 +871,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
 
         // Obtain the panic entry point.
         let (fn_abi, llfn, instance) =
-            common::build_langcall(bx, Some(source_info.span), LangItem::PanicNounwind);
+            common::build_langcall(bx, source_info.span, LangItem::PanicNounwind);
 
         // Codegen the actual panic invoke/call.
         Some(helper.do_call(
@@ -1830,7 +1830,8 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
 
         self.set_debug_loc(&mut bx, mir::SourceInfo::outermost(self.mir.span));
 
-        let (fn_abi, fn_ptr, instance) = common::build_langcall(&bx, None, reason.lang_item());
+        let (fn_abi, fn_ptr, instance) =
+            common::build_langcall(&bx, self.mir.span, reason.lang_item());
         if is_call_from_compiler_builtins_to_upstream_monomorphization(bx.tcx(), instance) {
             bx.abort();
         } else {

diff --git a/compiler/rustc_codegen_ssa/src/size_of_val.rs b/compiler/rustc_codegen_ssa/src/size_of_val.rs
@@ -5,6 +5,7 @@ use rustc_hir::LangItem;
 use rustc_middle::bug;
 use rustc_middle::ty::print::{with_no_trimmed_paths, with_no_visible_paths};
 use rustc_middle::ty::{self, Ty};
+use rustc_span::DUMMY_SP;
 use tracing::{debug, trace};
 
 use crate::common::IntPredicate;
@@ -62,7 +63,7 @@ pub fn size_and_align_of_dst<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
 
             // Obtain the panic entry point.
             let (fn_abi, llfn, _instance) =
-                common::build_langcall(bx, None, LangItem::PanicNounwind);
+                common::build_langcall(bx, DUMMY_SP, LangItem::PanicNounwind);
 
             // Generate the call. Cannot use `do_call` since we don't have a MIR terminator so we
             // can't create a `TerminationCodegenHelper`. (But we are in good company, this code is

diff --git a/compiler/rustc_const_eval/src/check_consts/ops.rs b/compiler/rustc_const_eval/src/check_consts/ops.rs
@@ -345,11 +345,7 @@ fn build_error_for_const_call<'tcx>(
                 non_or_conditionally,
             });
 
-            note_trait_if_possible(
-                &mut err,
-                self_ty,
-                tcx.require_lang_item(LangItem::Deref, Some(span)),
-            );
+            note_trait_if_possible(&mut err, self_ty, tcx.require_lang_item(LangItem::Deref, span));
             err
         }
         _ if tcx.opt_parent(callee) == tcx.get_diagnostic_item(sym::FmtArgumentsNew) => {

diff --git a/compiler/rustc_const_eval/src/check_consts/qualifs.rs b/compiler/rustc_const_eval/src/check_consts/qualifs.rs
@@ -99,7 +99,7 @@ impl Qualif for HasMutInterior {
         // requires borrowck, which in turn will invoke mir_const_qualifs again, causing a cycle error.
         // Instead we invoke an obligation context manually, and provide the opaque type inference settings
         // that allow the trait solver to just error out instead of cycling.
-        let freeze_def_id = cx.tcx.require_lang_item(LangItem::Freeze, Some(cx.body.span));
+        let freeze_def_id = cx.tcx.require_lang_item(LangItem::Freeze, cx.body.span);
         // FIXME(#132279): Once we've got a typing mode which reveals opaque types using the HIR
         // typeck results without causing query cycles, we should use this here instead of defining
         // opaque types.
@@ -180,7 +180,7 @@ impl Qualif for NeedsNonConstDrop {
         // that the components of this type are also `~const Destruct`. This
         // amounts to verifying that there are no values in this ADT that may have
         // a non-const drop.
-        let destruct_def_id = cx.tcx.require_lang_item(LangItem::Destruct, Some(cx.body.span));
+        let destruct_def_id = cx.tcx.require_lang_item(LangItem::Destruct, cx.body.span);
         let (infcx, param_env) = cx.tcx.infer_ctxt().build_with_typing_env(cx.typing_env);
         let ocx = ObligationCtxt::new(&infcx);
         ocx.register_obligation(Obligation::new(

diff --git a/compiler/rustc_const_eval/src/const_eval/eval_queries.rs b/compiler/rustc_const_eval/src/const_eval/eval_queries.rs
@@ -454,11 +454,12 @@ fn report_eval_error<'tcx>(
             // FIXME(oli-obk): figure out how to use structured diagnostics again.
             diag.code(E0080);
             diag.span_label(span, crate::fluent_generated::const_eval_error);
-            diag.arg("instance", instance);
-            diag.arg("error_kind", kind);
             for frame in frames {
                 diag.subdiagnostic(frame);
             }
+            // Add after the frame rendering above, as it adds its own `instance` args.
+            diag.arg("instance", instance);
+            diag.arg("error_kind", kind);
         },
     )
 }
-Original file line number
+Diff line change
@@ Expand Up / @@ -240,7 +240,7 @@ pub(crate) fn size_and_align_of<'tcx>( @@
                     })
                 });
-                codegen_panic_nounwind(fx, &msg_str, None);
+                codegen_panic_nounwind(fx, &msg_str, fx.mir.span);
                 fx.bcx.switch_to_block(next_block);
@@ Expand Down @@