Rollup of 12 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_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_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,