Rollup of 19 pull requests

bootstrap.example.toml

@@ -1013,9 +1013,10 @@
 # its historical default, but when compiling the compiler itself, we skip it by
 # default since we know it's safe to do so in that case.
 #
-# On Windows platforms, packed debuginfo is the only supported option,
-# producing a `.pdb` file.
-#split-debuginfo = if linux { off } else if windows { packed } else if apple { unpacked }
+# On Windows MSVC platforms, packed debuginfo is the only supported option,
+# producing a `.pdb` file. On Windows GNU rustc doesn't support splitting debuginfo,
+# and enabling it causes issues.
+#split-debuginfo = if linux || windows-gnu { off } else if windows-msvc { packed } else if apple { unpacked }
 
 # Path to the `llvm-config` binary of the installation of a custom LLVM to link
 # against. Note that if this is specified we don't compile LLVM at all for this

compiler/rustc_ast_lowering/src/lib.rs

@@ -1310,9 +1310,13 @@ impl<'hir, R: ResolverAstLoweringExt<'hir>> LoweringContext<'_, 'hir, R> {
                 }
                 GenericArg::Type(self.lower_ty_alloc(ty, itctx).try_as_ambig_ty().unwrap())
             }
-            ast::GenericArg::Const(ct) => GenericArg::Const(
-                self.lower_anon_const_to_const_arg_and_alloc(ct).try_as_ambig_ct().unwrap(),
-            ),
+            ast::GenericArg::Const(ct) => {
+                let ct = self.lower_anon_const_to_const_arg_and_alloc(ct);
+                match ct.try_as_ambig_ct() {
+                    Some(ct) => GenericArg::Const(ct),
+                    None => GenericArg::Infer(hir::InferArg { hir_id: ct.hir_id, span: ct.span }),
+                }
+            }
         }
     }
 

compiler/rustc_ast_pretty/src/pprust/state.rs

@@ -737,6 +737,23 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
             TokenTree::Token(token, spacing) => {
                 let token_str = self.token_to_string_ext(token, convert_dollar_crate);
                 self.word(token_str);
+                // Emit hygiene annotations for identity-bearing tokens,
+                // matching how print_ident() and print_lifetime() call ann_post().
+                match token.kind {
+                    token::Ident(name, _) => {
+                        self.ann_post(Ident::new(name, token.span));
+                    }
+                    token::NtIdent(ident, _) => {
+                        self.ann_post(ident);
+                    }
+                    token::Lifetime(name, _) => {
+                        self.ann_post(Ident::new(name, token.span));
+                    }
+                    token::NtLifetime(ident, _) => {
+                        self.ann_post(ident);
+                    }
+                    _ => {}
+                }
                 if let token::DocComment(..) = token.kind {
                     self.hardbreak()
                 }

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -374,10 +374,6 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         self.body
     }
 
-    fn unsized_feature_enabled(&self) -> bool {
-        self.tcx().features().unsized_fn_params()
-    }
-
     /// Equate the inferred type and the annotated type for user type annotations
     #[instrument(skip(self), level = "debug")]
     fn check_user_type_annotations(&mut self) {
@@ -660,7 +656,7 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
                     );
                 }
 
-                if !self.unsized_feature_enabled() {
+                if !self.tcx().features().unsized_fn_params() {
                     let trait_ref = ty::TraitRef::new(
                         tcx,
                         tcx.require_lang_item(LangItem::Sized, self.last_span),
@@ -936,9 +932,10 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
             }
         }
 
-        // When `unsized_fn_params` is enabled, only function calls
-        // and nullary ops are checked in `check_call_dest`.
-        if !self.unsized_feature_enabled() {
+        // When `unsized_fn_params` is enabled, this is checked in `check_call_dest`,
+        // and `hir_typeck` still forces all non-argument locals to be sized (i.e., we don't
+        // fully re-check what was already checked on HIR).
+        if !self.tcx().features().unsized_fn_params() {
             match self.body.local_kind(local) {
                 LocalKind::ReturnPointer | LocalKind::Arg => {
                     // return values of normal functions are required to be
@@ -1953,8 +1950,8 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
             }
 
             // When `unsized_fn_params` is not enabled,
-            // this check is done at `check_local`.
-            if self.unsized_feature_enabled() {
+            // this check is done at `visit_local_decl`.
+            if self.tcx().features().unsized_fn_params() {
                 let span = term.source_info.span;
                 self.ensure_place_sized(dest_ty, span);
             }

compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs

@@ -2874,6 +2874,9 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
         span: Span,
     ) -> Const<'tcx> {
         let tcx = self.tcx();
+
+        let ty = if !ty.has_infer() { Some(ty) } else { None };
+
         if let LitKind::Err(guar) = *kind {
             return ty::Const::new_error(tcx, guar);
         }
@@ -2905,16 +2908,20 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
         };
 
         let lit_input = match expr.kind {
-            hir::ExprKind::Lit(lit) => Some(LitToConstInput { lit: lit.node, ty, neg: false }),
+            hir::ExprKind::Lit(lit) => {
+                Some(LitToConstInput { lit: lit.node, ty: Some(ty), neg: false })
+            }
             hir::ExprKind::Unary(hir::UnOp::Neg, expr) => match expr.kind {
-                hir::ExprKind::Lit(lit) => Some(LitToConstInput { lit: lit.node, ty, neg: true }),
+                hir::ExprKind::Lit(lit) => {
+                    Some(LitToConstInput { lit: lit.node, ty: Some(ty), neg: true })
+                }
                 _ => None,
             },
             _ => None,
         };
 
         lit_input.and_then(|l| {
-            if const_lit_matches_ty(tcx, &l.lit, l.ty, l.neg) {
+            if const_lit_matches_ty(tcx, &l.lit, ty, l.neg) {
                 tcx.at(expr.span)
                     .lit_to_const(l)
                     .map(|value| ty::Const::new_value(tcx, value.valtree, value.ty))

compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs

@@ -11,7 +11,7 @@ use rustc_hir::attrs::DivergingBlockBehavior;
 use rustc_hir::def::{CtorKind, CtorOf, DefKind, Res};
 use rustc_hir::def_id::DefId;
 use rustc_hir::intravisit::Visitor;
-use rustc_hir::{Expr, ExprKind, HirId, LangItem, Node, QPath, is_range_literal};
+use rustc_hir::{Expr, ExprKind, FnRetTy, HirId, LangItem, Node, QPath, is_range_literal};
 use rustc_hir_analysis::check::potentially_plural_count;
 use rustc_hir_analysis::hir_ty_lowering::{HirTyLowerer, PermitVariants};
 use rustc_index::IndexVec;
@@ -1587,6 +1587,45 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 }
             }
             err.span_note(spans, format!("{} defined here", self.tcx.def_descr(def_id)));
+            if let DefKind::Fn | DefKind::AssocFn = self.tcx.def_kind(def_id)
+                && let ty::Param(_) =
+                    self.tcx.fn_sig(def_id).instantiate_identity().skip_binder().output().kind()
+                && let parent = self.tcx.hir_get_parent_item(call_expr.hir_id).def_id
+                && let Some((output, body_id)) = match self.tcx.hir_node_by_def_id(parent) {
+                    hir::Node::Item(hir::Item {
+                        kind: hir::ItemKind::Fn { sig, body, .. },
+                        ..
+                    })
+                    | hir::Node::TraitItem(hir::TraitItem {
+                        kind: hir::TraitItemKind::Fn(sig, hir::TraitFn::Provided(body)),
+                        ..
+                    })
+                    | hir::Node::ImplItem(hir::ImplItem {
+                        kind: hir::ImplItemKind::Fn(sig, body),
+                        ..
+                    }) => Some((sig.decl.output, body)),
+                    _ => None,
+                }
+                && let expr = self.tcx.hir_body(*body_id).value
+                && (expr.peel_blocks().span == call_expr.span
+                    || matches!(
+                        self.tcx.parent_hir_node(call_expr.hir_id),
+                        hir::Node::Expr(hir::Expr { kind: hir::ExprKind::Ret(_), .. })
+                    ))
+            {
+                err.span_label(
+                    output.span(),
+                    match output {
+                        FnRetTy::DefaultReturn(_) => format!(
+                            "this implicit `()` return type influences the call expression's return type"
+                        ),
+                        FnRetTy::Return(_) => {
+                            "this return type influences the call expression's return type"
+                                .to_string()
+                        }
+                    },
+                );
+            }
         } else if let Some(hir::Node::Expr(e)) = self.tcx.hir_get_if_local(def_id)
             && let hir::ExprKind::Closure(hir::Closure { body, .. }) = &e.kind
         {

compiler/rustc_lint/src/for_loops_over_fallibles.rs

@@ -49,6 +49,11 @@ impl<'tcx> LateLintPass<'tcx> for ForLoopsOverFallibles {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         let Some((pat, arg)) = extract_for_loop(expr) else { return };
 
+        // Do not put suggestions for external macros.
+        if pat.span.from_expansion() {
+            return;
+        }
+
         let arg_span = arg.span.source_callsite();
 
         let ty = cx.typeck_results().expr_ty(arg);
@@ -77,6 +82,8 @@ impl<'tcx> LateLintPass<'tcx> for ForLoopsOverFallibles {
         };
 
         let sub = if let Some(recv) = extract_iterator_next_call(cx, arg)
+            && recv.span.can_be_used_for_suggestions()
+            && recv.span.between(arg_span.shrink_to_hi()).can_be_used_for_suggestions()
             && let Ok(recv_snip) = cx.sess().source_map().span_to_snippet(recv.span)
         {
             ForLoopsOverFalliblesLoopSub::RemoveNext {

compiler/rustc_middle/src/queries.rs

@@ -101,7 +101,7 @@ use crate::mir::mono::{
     CodegenUnit, CollectionMode, MonoItem, MonoItemPartitions, NormalizationErrorInMono,
 };
 use crate::query::describe_as_module;
-use crate::query::plumbing::{define_callbacks, query_helper_param_ty};
+use crate::query::plumbing::{define_callbacks, maybe_into_query_key};
 use crate::traits::query::{
     CanonicalAliasGoal, CanonicalDropckOutlivesGoal, CanonicalImpliedOutlivesBoundsGoal,
     CanonicalMethodAutoderefStepsGoal, CanonicalPredicateGoal, CanonicalTypeOpAscribeUserTypeGoal,