Auto merge of #135151 - matthiaskrgr:rollup-2vy1hwl, r=matthiaskrgr

Rollup of 6 pull requests

Successful merges:

 - #135111 (Add doc aliases for `libm` and IEEE names)
 - #135129 (triagebot: label `src/doc/rustc-dev-guide` changes with `A-rustc-dev-guide`)
 - #135132 (dev guide ping group and set adhoc reviewers to compiler)
 - #135145 (Mention `unnameable_types` in `unreachable_pub` documentation.)
 - #135147 (A few borrowck tweaks to improve 2024 edition migration lints)
 - #135150 (move footnote to ordinary comment)

r? `@ghost`
`@rustbot` modify labels: rollup

6 files changed, 77 insertions, 47 deletions

diff --git a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
index 22f7f708419..87017460e8e 100644
--- a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
@@ -17,6 +17,7 @@ use rustc_middle::mir::{
 };
 use rustc_middle::ty::adjustment::PointerCoercion;
 use rustc_middle::ty::{self, RegionVid, Ty, TyCtxt};
+use rustc_middle::util::CallKind;
 use rustc_span::{DesugaringKind, Span, Symbol, kw, sym};
 use rustc_trait_selection::error_reporting::traits::FindExprBySpan;
 use tracing::{debug, instrument};
@@ -635,6 +636,39 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, 'tcx> {
                 // Used in a closure.
                 (LaterUseKind::ClosureCapture, capture_kind_span, Some(path_span))
             }
+            // In the case that the borrowed value (probably a temporary)
+            // overlaps with the method's receiver, then point at the method.
+            UseSpans::FnSelfUse {
+                var_span: span,
+                kind: CallKind::Normal { desugaring: None, .. },
+                ..
+            } if span
+                .overlaps(self.body.local_decls[borrow.assigned_place.local].source_info.span) =>
+            {
+                if let TerminatorKind::Call { func, call_source: CallSource::Normal, .. } =
+                    &self.body.basic_blocks[location.block].terminator().kind
+                {
+                    // Just point to the function, to reduce the chance of overlapping spans.
+                    let function_span = match func {
+                        Operand::Constant(c) => c.span,
+                        Operand::Copy(place) | Operand::Move(place) => {
+                            if let Some(l) = place.as_local() {
+                                let local_decl = &self.body.local_decls[l];
+                                if self.local_names[l].is_none() {
+                                    local_decl.source_info.span
+                                } else {
+                                    span
+                                }
+                            } else {
+                                span
+                            }
+                        }
+                    };
+                    (LaterUseKind::Call, function_span, None)
+                } else {
+                    (LaterUseKind::Other, span, None)
+                }
+            }
             UseSpans::PatUse(span)
             | UseSpans::OtherUse(span)
             | UseSpans::FnSelfUse { var_span: span, .. } => {
diff --git a/compiler/rustc_borrowck/src/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs
index 180046ca256..ebbdfea302c 100644
--- a/compiler/rustc_borrowck/src/diagnostics/mod.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs
@@ -661,9 +661,6 @@ impl UseSpans<'_> {
             UseSpans::ClosureUse { args_span: span, .. }
             | UseSpans::PatUse(span)
             | UseSpans::OtherUse(span) => span,
-            UseSpans::FnSelfUse { fn_call_span, kind: CallKind::DerefCoercion { .. }, .. } => {
-                fn_call_span
-            }
             UseSpans::FnSelfUse { var_span, .. } => var_span,
         }
     }
@@ -674,9 +671,6 @@ impl UseSpans<'_> {
             UseSpans::ClosureUse { path_span: span, .. }
             | UseSpans::PatUse(span)
             | UseSpans::OtherUse(span) => span,
-            UseSpans::FnSelfUse { fn_call_span, kind: CallKind::DerefCoercion { .. }, .. } => {
-                fn_call_span
-            }
             UseSpans::FnSelfUse { var_span, .. } => var_span,
         }
     }
@@ -687,9 +681,6 @@ impl UseSpans<'_> {
             UseSpans::ClosureUse { capture_kind_span: span, .. }
             | UseSpans::PatUse(span)
             | UseSpans::OtherUse(span) => span,
-            UseSpans::FnSelfUse { fn_call_span, kind: CallKind::DerefCoercion { .. }, .. } => {
-                fn_call_span
-            }
             UseSpans::FnSelfUse { var_span, .. } => var_span,
         }
     }
diff --git a/compiler/rustc_hir_analysis/src/impl_wf_check.rs b/compiler/rustc_hir_analysis/src/impl_wf_check.rs
index bb122009593..42034736ad6 100644
--- a/compiler/rustc_hir_analysis/src/impl_wf_check.rs
+++ b/compiler/rustc_hir_analysis/src/impl_wf_check.rs
@@ -128,21 +128,7 @@ pub(crate) fn enforce_impl_lifetime_params_are_constrained(
     for param in &impl_generics.own_params {
         match param.kind {
             ty::GenericParamDefKind::Lifetime => {
-                let param_lt = cgp::Parameter::from(param.to_early_bound_region_data());
-                if lifetimes_in_associated_types.contains(&param_lt) // (*)
-                    && !input_parameters.contains(&param_lt)
-                {
-                    let mut diag = tcx.dcx().create_err(UnconstrainedGenericParameter {
-                        span: tcx.def_span(param.def_id),
-                        param_name: param.name,
-                        param_def_kind: tcx.def_descr(param.def_id),
-                        const_param_note: false,
-                        const_param_note2: false,
-                    });
-                    diag.code(E0207);
-                    res = Err(diag.emit());
-                }
-                // (*) This is a horrible concession to reality. I think it'd be
+                // This is a horrible concession to reality. I think it'd be
                 // better to just ban unconstrained lifetimes outright, but in
                 // practice people do non-hygienic macros like:
                 //
@@ -160,6 +146,20 @@ pub(crate) fn enforce_impl_lifetime_params_are_constrained(
                 // permit those, so long as the lifetimes aren't used in
                 // associated types. I believe this is sound, because lifetimes
                 // used elsewhere are not projected back out.
+                let param_lt = cgp::Parameter::from(param.to_early_bound_region_data());
+                if lifetimes_in_associated_types.contains(&param_lt)
+                    && !input_parameters.contains(&param_lt)
+                {
+                    let mut diag = tcx.dcx().create_err(UnconstrainedGenericParameter {
+                        span: tcx.def_span(param.def_id),
+                        param_name: param.name,
+                        param_def_kind: tcx.def_descr(param.def_id),
+                        const_param_note: false,
+                        const_param_note2: false,
+                    });
+                    diag.code(E0207);
+                    res = Err(diag.emit());
+                }
             }
             ty::GenericParamDefKind::Type { .. } | ty::GenericParamDefKind::Const { .. } => {
                 // Enforced in `enforce_impl_non_lifetime_params_are_constrained`.
diff --git a/compiler/rustc_lint/src/builtin.rs b/compiler/rustc_lint/src/builtin.rs
index 2feed5e80dc..e74fb9d92e9 100644
--- a/compiler/rustc_lint/src/builtin.rs
+++ b/compiler/rustc_lint/src/builtin.rs
@@ -1244,8 +1244,8 @@ impl<'tcx> LateLintPass<'tcx> for UngatedAsyncFnTrackCaller {
 
 declare_lint! {
     /// The `unreachable_pub` lint triggers for `pub` items not reachable from other crates - that
-    /// means neither directly accessible, nor reexported, nor leaked through things like return
-    /// types.
+    /// means neither directly accessible, nor reexported (with `pub use`), nor leaked through
+    /// things like return types (which the [`unnameable_types`] lint can detect if desired).
     ///
     /// ### Example
     ///
@@ -1272,8 +1272,10 @@ declare_lint! {
     /// intent that the item is only visible within its own crate.
     ///
     /// This lint is "allow" by default because it will trigger for a large
-    /// amount existing Rust code, and has some false-positives. Eventually it
+    /// amount of existing Rust code, and has some false-positives. Eventually it
     /// is desired for this to become warn-by-default.
+    ///
+    /// [`unnameable_types`]: #unnameable-types
     pub UNREACHABLE_PUB,
     Allow,
     "`pub` items not reachable from crate root"
diff --git a/compiler/rustc_lint_defs/src/builtin.rs b/compiler/rustc_lint_defs/src/builtin.rs
index 2f23ab27492..8399f4c12f4 100644
--- a/compiler/rustc_lint_defs/src/builtin.rs
+++ b/compiler/rustc_lint_defs/src/builtin.rs
@@ -4362,7 +4362,7 @@ declare_lint! {
     /// ### Explanation
     ///
     /// It is often expected that if you can obtain an object of type `T`, then
-    /// you can name the type `T` as well, this lint attempts to enforce this rule.
+    /// you can name the type `T` as well; this lint attempts to enforce this rule.
     /// The recommended action is to either reexport the type properly to make it nameable,
     /// or document that users are not supposed to be able to name it for one reason or another.
     ///
diff --git a/compiler/rustc_middle/src/util/find_self_call.rs b/compiler/rustc_middle/src/util/find_self_call.rs
index ec6051d0a77..0fdd3520738 100644
--- a/compiler/rustc_middle/src/util/find_self_call.rs
+++ b/compiler/rustc_middle/src/util/find_self_call.rs
@@ -17,26 +17,29 @@ pub fn find_self_call<'tcx>(
     debug!("find_self_call(local={:?}): terminator={:?}", local, body[block].terminator);
     if let Some(Terminator { kind: TerminatorKind::Call { func, args, .. }, .. }) =
         &body[block].terminator
+        && let Operand::Constant(box ConstOperand { const_, .. }) = func
+        && let ty::FnDef(def_id, fn_args) = *const_.ty().kind()
+        && let Some(ty::AssocItem { fn_has_self_parameter: true, .. }) =
+            tcx.opt_associated_item(def_id)
+        && let [Spanned { node: Operand::Move(self_place) | Operand::Copy(self_place), .. }, ..] =
+            **args
     {
-        debug!("find_self_call: func={:?}", func);
-        if let Operand::Constant(box ConstOperand { const_, .. }) = func {
-            if let ty::FnDef(def_id, fn_args) = *const_.ty().kind() {
-                if let Some(ty::AssocItem { fn_has_self_parameter: true, .. }) =
-                    tcx.opt_associated_item(def_id)
-                {
-                    debug!("find_self_call: args={:?}", fn_args);
-                    if let [
-                        Spanned {
-                            node: Operand::Move(self_place) | Operand::Copy(self_place), ..
-                        },
-                        ..,
-                    ] = **args
-                    {
-                        if self_place.as_local() == Some(local) {
-                            return Some((def_id, fn_args));
-                        }
-                    }
-                }
+        if self_place.as_local() == Some(local) {
+            return Some((def_id, fn_args));
+        }
+
+        // Handle the case where `self_place` gets reborrowed.
+        // This happens when the receiver is `&T`.
+        for stmt in &body[block].statements {
+            if let StatementKind::Assign(box (place, rvalue)) = &stmt.kind
+                && let Some(reborrow_local) = place.as_local()
+                && self_place.as_local() == Some(reborrow_local)
+                && let Rvalue::Ref(_, _, deref_place) = rvalue
+                && let PlaceRef { local: deref_local, projection: [ProjectionElem::Deref] } =
+                    deref_place.as_ref()
+                && deref_local == local
+            {
+                return Some((def_id, fn_args));
             }
         }
     }