Fix spans

compiler/rustc_codegen_cranelift/src/abi/mod.rs

@@ -376,7 +376,7 @@ pub(crate) fn codegen_terminator_call<'tcx>(
             ty::ParamEnv::reveal_all(),
             def_id,
             fn_args,
-            Some(source_info.span),
+            source_info.span,
         )
         .polymorphize(fx.tcx);
 

compiler/rustc_codegen_cranelift/src/main_shim.rs

@@ -4,6 +4,7 @@
 use rustc_middle::ty::GenericArg;
 use rustc_session::config::{sigpipe, EntryFnType};
 use rustc_span::symbol::Ident;
+use rustc_span::DUMMY_SP;
 
 use crate::prelude::*;
 
@@ -119,7 +120,7 @@ fn create_entry_fn(
                     ParamEnv::reveal_all(),
                     report.def_id,
                     tcx.mk_args(&[GenericArg::from(main_ret_ty)]),
-                    None,
+                    DUMMY_SP,
                 )
                 .polymorphize(tcx);
 
@@ -145,7 +146,7 @@ fn create_entry_fn(
                     ParamEnv::reveal_all(),
                     start_def_id,
                     tcx.mk_args(&[main_ret_ty.into()]),
-                    None,
+                    DUMMY_SP,
                 )
                 .polymorphize(tcx);
                 let start_func_id = import_function(tcx, m, start_instance);

compiler/rustc_codegen_gcc/src/context.rs

@@ -17,7 +17,7 @@
 };
 use rustc_middle::ty::{self, Instance, ParamEnv, PolyExistentialTraitRef, Ty, TyCtxt};
 use rustc_session::Session;
-use rustc_span::{source_map::respan, Span};
+use rustc_span::{source_map::respan, Span, DUMMY_SP};
 use rustc_target::abi::{
     call::FnAbi, HasDataLayout, PointeeInfo, Size, TargetDataLayout, VariantIdx,
 };
@@ -479,7 +479,7 @@ fn eh_personality(&self) -> RValue<'gcc> {
                     ty::ParamEnv::reveal_all(),
                     def_id,
                     ty::List::empty(),
-                    None,
+                    DUMMY_SP,
                 );
 
                 let symbol_name = tcx.symbol_name(instance).name;

compiler/rustc_codegen_llvm/src/context.rs

@@ -28,7 +28,7 @@
 use rustc_session::config::{CrateType, DebugInfo, PAuthKey, PacRet};
 use rustc_session::Session;
 use rustc_span::source_map::Spanned;
-use rustc_span::Span;
+use rustc_span::{Span, DUMMY_SP};
 use rustc_target::abi::{call::FnAbi, HasDataLayout, TargetDataLayout, VariantIdx};
 use rustc_target::spec::{HasTargetSpec, RelocModel, Target, TlsModel};
 use smallvec::SmallVec;
@@ -580,7 +580,7 @@ fn eh_personality(&self) -> &'ll Value {
                 ty::ParamEnv::reveal_all(),
                 def_id,
                 ty::List::empty(),
-                None,
+                DUMMY_SP,
             )),
             _ => {
                 let name = name.unwrap_or("rust_eh_personality");

compiler/rustc_codegen_ssa/src/base.rs

@@ -37,7 +37,7 @@
 use rustc_session::config::{self, CrateType, EntryFnType, OptLevel, OutputType};
 use rustc_session::Session;
 use rustc_span::symbol::sym;
-use rustc_span::Symbol;
+use rustc_span::{Symbol, DUMMY_SP};
 use rustc_target::abi::FIRST_VARIANT;
 
 use std::cmp;
@@ -467,7 +467,7 @@ fn create_entry_fn<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
                 ty::ParamEnv::reveal_all(),
                 start_def_id,
                 cx.tcx().mk_args(&[main_ret_ty.into()]),
-                None,
+                DUMMY_SP,
             );
             let start_fn = cx.get_fn_addr(start_instance);
 

compiler/rustc_codegen_ssa/src/mir/block.rs

@@ -842,7 +842,7 @@ fn codegen_call_terminator(
                         ty::ParamEnv::reveal_all(),
                         def_id,
                         args,
-                        Some(fn_span),
+                        fn_span,
                     )
                     .polymorphize(bx.tcx()),
                 ),

compiler/rustc_const_eval/src/const_eval/machine.rs

@@ -253,7 +253,7 @@ fn hook_special_const_fn(
                 ty::ParamEnv::reveal_all(),
                 const_def_id,
                 instance.args,
-                Some(self.find_closest_untracked_caller_location()),
+                self.cur_span(),
             );
 
             return Ok(Some(new_instance));

compiler/rustc_const_eval/src/interpret/terminator.rs

@@ -888,6 +888,7 @@ pub(crate) fn eval_fn_call(
                         self.param_env,
                         def_id,
                         instance.args.rebase_onto(tcx, trait_def_id, concrete_trait_ref.args),
+                        self.cur_span(),
                     );
                     assert_eq!(fn_inst, concrete_method);
                 }

compiler/rustc_middle/src/ty/instance.rs

@@ -547,8 +547,14 @@ pub fn expect_resolve(
         param_env: ty::ParamEnv<'tcx>,
         def_id: DefId,
         args: GenericArgsRef<'tcx>,
-        span: Option<Span>,
+        span: Span,
     ) -> Instance<'tcx> {
+        // We compute the span lazily, to avoid unnecessary query calls.
+        // If `span` is a DUMMY_SP, and the def id is local, then use the
+        // def span of the def id.
+        let span_or_local_def_span =
+            || if span.is_dummy() && def_id.is_local() { tcx.def_span(def_id) } else { span };
+
         match ty::Instance::resolve(tcx, param_env, def_id, args) {
             Ok(Some(instance)) => instance,
             Ok(None) => {
@@ -567,7 +573,7 @@ pub fn expect_resolve(
                         // We don't use `def_span(def_id)` so that diagnostics point
                         // to the crate root during mono instead of to foreign items.
                         // This is arguably better.
-                        span: span.unwrap_or(DUMMY_SP),
+                        span: span_or_local_def_span(),
                         shrunk,
                         was_written,
                         path,
@@ -575,14 +581,14 @@ pub fn expect_resolve(
                     });
                 } else {
                     span_bug!(
-                        span.unwrap_or(tcx.def_span(def_id)),
+                        span_or_local_def_span(),
                         "failed to resolve instance for {}",
                         tcx.def_path_str_with_args(def_id, args)
                     )
                 }
             }
             instance => span_bug!(
-                span.unwrap_or(tcx.def_span(def_id)),
+                span_or_local_def_span(),
                 "failed to resolve instance for {}: {instance:#?}",
                 tcx.def_path_str_with_args(def_id, args)
             ),
@@ -642,6 +648,7 @@ pub fn expect_resolve_for_vtable(
         param_env: ty::ParamEnv<'tcx>,
         def_id: DefId,
         args: GenericArgsRef<'tcx>,
+        span: Span,
     ) -> Instance<'tcx> {
         debug!("resolve_for_vtable(def_id={:?}, args={:?})", def_id, args);
         let fn_sig = tcx.fn_sig(def_id).instantiate_identity();
@@ -654,7 +661,7 @@ pub fn expect_resolve_for_vtable(
             return Instance { def: InstanceKind::VTableShim(def_id), args };
         }
 
-        let mut resolved = Instance::expect_resolve(tcx, param_env, def_id, args, None);
+        let mut resolved = Instance::expect_resolve(tcx, param_env, def_id, args, span);
 
         let reason = tcx.sess.is_sanitizer_kcfi_enabled().then_some(ReifyReason::Vtable);
         match resolved.def {
@@ -731,13 +738,13 @@ pub fn resolve_closure(
     pub fn resolve_drop_in_place(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> ty::Instance<'tcx> {
         let def_id = tcx.require_lang_item(LangItem::DropInPlace, None);
         let args = tcx.mk_args(&[ty.into()]);
-        Instance::expect_resolve(tcx, ty::ParamEnv::reveal_all(), def_id, args, None)
+        Instance::expect_resolve(tcx, ty::ParamEnv::reveal_all(), def_id, args, DUMMY_SP)
     }
 
     pub fn resolve_async_drop_in_place(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> ty::Instance<'tcx> {
         let def_id = tcx.require_lang_item(LangItem::AsyncDropInPlace, None);
         let args = tcx.mk_args(&[ty.into()]);
-        Instance::expect_resolve(tcx, ty::ParamEnv::reveal_all(), def_id, args, None)
+        Instance::expect_resolve(tcx, ty::ParamEnv::reveal_all(), def_id, args, DUMMY_SP)
     }
 
     #[instrument(level = "debug", skip(tcx), ret)]

compiler/rustc_monomorphize/src/collector.rs

@@ -853,13 +853,7 @@ fn visit_fn_use<'tcx>(
 ) {
     if let ty::FnDef(def_id, args) = *ty.kind() {
         let instance = if is_direct_call {
-            ty::Instance::expect_resolve(
-                tcx,
-                ty::ParamEnv::reveal_all(),
-                def_id,
-                args,
-                Some(source),
-            )
+            ty::Instance::expect_resolve(tcx, ty::ParamEnv::reveal_all(), def_id, args, source)
         } else {
             match ty::Instance::resolve_for_fn_ptr(tcx, ty::ParamEnv::reveal_all(), def_id, args) {
                 Some(instance) => instance,
@@ -1261,13 +1255,8 @@ fn visit_mentioned_item<'tcx>(
     match *item {
         MentionedItem::Fn(ty) => {
             if let ty::FnDef(def_id, args) = *ty.kind() {
-                let instance = Instance::expect_resolve(
-                    tcx,
-                    ty::ParamEnv::reveal_all(),
-                    def_id,
-                    args,
-                    Some(span),
-                );
+                let instance =
+                    Instance::expect_resolve(tcx, ty::ParamEnv::reveal_all(), def_id, args, span);
                 // `visit_instance_use` was written for "used" item collection but works just as well
                 // for "mentioned" item collection.
                 // We can set `is_direct_call`; that just means we'll skip a bunch of shims that anyway
@@ -1492,7 +1481,7 @@ fn push_extra_entry_roots(&mut self) {
             ty::ParamEnv::reveal_all(),
             start_def_id,
             self.tcx.mk_args(&[main_ret_ty.into()]),
-            None,
+            DUMMY_SP,
         );
 
         self.output.push(create_fn_mono_item(self.tcx, start_instance, DUMMY_SP));
@@ -1561,9 +1550,10 @@ fn create_mono_items_for_default_impls<'tcx>(
         }
 
         // As mentioned above, the method is legal to eagerly instantiate if it
-        // only has lifetime generic parameters. This is validated by
+        // only has lifetime generic parameters. This is validated by calling
+        // `own_requires_monomorphization` on both the impl and method.
         let args = trait_ref.args.extend_to(tcx, method.def_id, only_region_params);
-        let instance = ty::Instance::expect_resolve(tcx, param_env, method.def_id, args, None);
+        let instance = ty::Instance::expect_resolve(tcx, param_env, method.def_id, args, DUMMY_SP);
 
         let mono_item = create_fn_mono_item(tcx, instance, DUMMY_SP);
         if mono_item.node.is_instantiable(tcx) && should_codegen_locally(tcx, instance) {

compiler/rustc_trait_selection/src/traits/vtable.rs

@@ -6,7 +6,7 @@
 use rustc_middle::query::Providers;
 use rustc_middle::ty::{self, GenericParamDefKind, Ty, TyCtxt, Upcast, VtblEntry};
 use rustc_middle::ty::{GenericArgs, TypeVisitableExt};
-use rustc_span::{sym, Span};
+use rustc_span::{sym, Span, DUMMY_SP};
 use smallvec::{smallvec, SmallVec};
 
 use std::fmt::Debug;
@@ -290,6 +290,7 @@ fn vtable_entries<'tcx>(
                         ty::ParamEnv::reveal_all(),
                         def_id,
                         args,
+                        DUMMY_SP,
                     );
 
                     VtblEntry::Method(instance)