Auto merge of rust-lang#121870 - matthiaskrgr:rollup-mfpa3jx, r=matth…

…iaskrgr

Rollup of 11 pull requests

Successful merges:

 - rust-lang#111505 (Made `INVALID_DOC_ATTRIBUTES` lint deny by default)
 - rust-lang#120305 (Delete line if suggestion would replace it with an empty line)
 - rust-lang#121153 (Suggest removing superfluous semicolon when statements used as expression)
 - rust-lang#121497 (`-Znext-solver=coherence`: suggest increasing recursion limit)
 - rust-lang#121634 (Clarify behavior of slice prefix/suffix operations in case of equality)
 - rust-lang#121706 (match lowering: Remove hacky branch in sort_candidate)
 - rust-lang#121730 (Add profiling support to AIX)
 - rust-lang#121750 (match lowering: Separate the `bool` case from other integers in `TestKind`)
 - rust-lang#121803 (Never say "`Trait` is implemented for `{type error}`")
 - rust-lang#121811 (Move sanitizer ui tests to sanitizer directory)
 - rust-lang#121824 (Implement missing ABI structures in StableMIR)

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

compiler/rustc_codegen_ssa/src/back/linker.rs

@@ -1631,7 +1631,9 @@ impl<'a> Linker for AixLinker<'a> {
 
     fn optimize(&mut self) {}
 
-    fn pgo_gen(&mut self) {}
+    fn pgo_gen(&mut self) {
+        self.cmd.arg("-bdbg:namedsects:ss");
+    }
 
     fn control_flow_guard(&mut self) {}
 

compiler/rustc_errors/src/json.rs

@@ -428,14 +428,24 @@ impl DiagnosticSpan {
     }
 
     fn from_span_full(
-        span: Span,
+        mut span: Span,
         is_primary: bool,
         label: Option<String>,
         suggestion: Option<(&String, Applicability)>,
         mut backtrace: impl Iterator<Item = ExpnData>,
         je: &JsonEmitter,
     ) -> DiagnosticSpan {
         let start = je.sm.lookup_char_pos(span.lo());
+        // If this goes from the start of a line to the end and the replacement
+        // is an empty string, increase the length to include the newline so we don't
+        // leave an empty line
+        if start.col.0 == 0
+            && suggestion.map_or(false, |(s, _)| s.is_empty())
+            && let Ok(after) = je.sm.span_to_next_source(span)
+            && after.starts_with('\n')
+        {
+            span = span.with_hi(span.hi() + rustc_span::BytePos(1));
+        }
         let end = je.sm.lookup_char_pos(span.hi());
         let backtrace_step = backtrace.next().map(|bt| {
             let call_site = Self::from_span_full(bt.call_site, false, None, None, backtrace, je);

compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs

@@ -1744,7 +1744,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                         Ty::new_unit(self.tcx),
                                     );
                                 }
-                                if !self.consider_removing_semicolon(blk, expected_ty, err) {
+                                if !self.err_ctxt().consider_removing_semicolon(
+                                    blk,
+                                    expected_ty,
+                                    err,
+                                ) {
                                     self.err_ctxt().consider_returning_binding(
                                         blk,
                                         expected_ty,

compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs

@@ -22,7 +22,7 @@ use rustc_hir::{
     Path, QPath, Stmt, StmtKind, TyKind, WherePredicate,
 };
 use rustc_hir_analysis::astconv::AstConv;
-use rustc_infer::traits::{self, StatementAsExpression};
+use rustc_infer::traits::{self};
 use rustc_middle::lint::in_external_macro;
 use rustc_middle::middle::stability::EvalResult;
 use rustc_middle::ty::print::with_no_trimmed_paths;
@@ -1791,45 +1791,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         }
     }
 
-    /// A common error is to add an extra semicolon:
-    ///
-    /// ```compile_fail,E0308
-    /// fn foo() -> usize {
-    ///     22;
-    /// }
-    /// ```
-    ///
-    /// This routine checks if the final statement in a block is an
-    /// expression with an explicit semicolon whose type is compatible
-    /// with `expected_ty`. If so, it suggests removing the semicolon.
-    pub(crate) fn consider_removing_semicolon(
-        &self,
-        blk: &'tcx hir::Block<'tcx>,
-        expected_ty: Ty<'tcx>,
-        err: &mut Diag<'_>,
-    ) -> bool {
-        if let Some((span_semi, boxed)) = self.err_ctxt().could_remove_semicolon(blk, expected_ty) {
-            if let StatementAsExpression::NeedsBoxing = boxed {
-                err.span_suggestion_verbose(
-                    span_semi,
-                    "consider removing this semicolon and boxing the expression",
-                    "",
-                    Applicability::HasPlaceholders,
-                );
-            } else {
-                err.span_suggestion_short(
-                    span_semi,
-                    "remove this semicolon to return this value",
-                    "",
-                    Applicability::MachineApplicable,
-                );
-            }
-            true
-        } else {
-            false
-        }
-    }
-
     pub(crate) fn is_field_suggestable(
         &self,
         field: &ty::FieldDef,

compiler/rustc_infer/src/infer/error_reporting/mod.rs

@@ -1989,6 +1989,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                 self.suggest_accessing_field_where_appropriate(cause, &exp_found, diag);
                 self.suggest_await_on_expect_found(cause, span, &exp_found, diag);
                 self.suggest_function_pointers(cause, span, &exp_found, diag);
+                self.suggest_turning_stmt_into_expr(cause, &exp_found, diag);
             }
         }
 

compiler/rustc_infer/src/infer/error_reporting/suggest.rs

@@ -1,8 +1,13 @@
+use crate::infer::error_reporting::hir::Path;
 use hir::def::CtorKind;
 use hir::intravisit::{walk_expr, walk_stmt, Visitor};
+use hir::{Local, QPath};
 use rustc_data_structures::fx::FxIndexSet;
 use rustc_errors::{Applicability, Diag};
 use rustc_hir as hir;
+use rustc_hir::def::Res;
+use rustc_hir::MatchSource;
+use rustc_hir::Node;
 use rustc_middle::traits::{
     IfExpressionCause, MatchExpressionArmCause, ObligationCause, ObligationCauseCode,
     StatementAsExpression,
@@ -293,6 +298,97 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         }
     }
 
+    pub(super) fn suggest_turning_stmt_into_expr(
+        &self,
+        cause: &ObligationCause<'tcx>,
+        exp_found: &ty::error::ExpectedFound<Ty<'tcx>>,
+        diag: &mut Diag<'_>,
+    ) {
+        let ty::error::ExpectedFound { expected, found } = exp_found;
+        if !found.peel_refs().is_unit() {
+            return;
+        }
+
+        let ObligationCauseCode::BlockTailExpression(hir_id, MatchSource::Normal) = cause.code()
+        else {
+            return;
+        };
+
+        let node = self.tcx.hir_node(*hir_id);
+        let mut blocks = vec![];
+        if let hir::Node::Block(block) = node
+            && let Some(expr) = block.expr
+            && let hir::ExprKind::Path(QPath::Resolved(_, Path { res, .. })) = expr.kind
+            && let Res::Local(local) = res
+            && let Node::Local(Local { init: Some(init), .. }) = self.tcx.parent_hir_node(*local)
+        {
+            fn collect_blocks<'hir>(expr: &hir::Expr<'hir>, blocks: &mut Vec<&hir::Block<'hir>>) {
+                match expr.kind {
+                    // `blk1` and `blk2` must be have the same types, it will be reported before reaching here
+                    hir::ExprKind::If(_, blk1, Some(blk2)) => {
+                        collect_blocks(blk1, blocks);
+                        collect_blocks(blk2, blocks);
+                    }
+                    hir::ExprKind::Match(_, arms, _) => {
+                        // all arms must have same types
+                        for arm in arms.iter() {
+                            collect_blocks(arm.body, blocks);
+                        }
+                    }
+                    hir::ExprKind::Block(blk, _) => {
+                        blocks.push(blk);
+                    }
+                    _ => {}
+                }
+            }
+            collect_blocks(init, &mut blocks);
+        }
+
+        let expected_inner: Ty<'_> = expected.peel_refs();
+        for block in blocks.iter() {
+            self.consider_removing_semicolon(block, expected_inner, diag);
+        }
+    }
+
+    /// A common error is to add an extra semicolon:
+    ///
+    /// ```compile_fail,E0308
+    /// fn foo() -> usize {
+    ///     22;
+    /// }
+    /// ```
+    ///
+    /// This routine checks if the final statement in a block is an
+    /// expression with an explicit semicolon whose type is compatible
+    /// with `expected_ty`. If so, it suggests removing the semicolon.
+    pub fn consider_removing_semicolon(
+        &self,
+        blk: &'tcx hir::Block<'tcx>,
+        expected_ty: Ty<'tcx>,
+        diag: &mut Diag<'_>,
+    ) -> bool {
+        if let Some((span_semi, boxed)) = self.could_remove_semicolon(blk, expected_ty) {
+            if let StatementAsExpression::NeedsBoxing = boxed {
+                diag.span_suggestion_verbose(
+                    span_semi,
+                    "consider removing this semicolon and boxing the expression",
+                    "",
+                    Applicability::HasPlaceholders,
+                );
+            } else {
+                diag.span_suggestion_short(
+                    span_semi,
+                    "remove this semicolon to return this value",
+                    "",
+                    Applicability::MachineApplicable,
+                );
+            }
+            true
+        } else {
+            false
+        }
+    }
+
     pub(super) fn suggest_function_pointers(
         &self,
         cause: &ObligationCause<'tcx>,

compiler/rustc_infer/src/traits/mod.rs

@@ -135,16 +135,18 @@ pub struct FulfillmentError<'tcx> {
 
 #[derive(Clone)]
 pub enum FulfillmentErrorCode<'tcx> {
-    /// Inherently impossible to fulfill; this trait is implemented if and only if it is already implemented.
+    /// Inherently impossible to fulfill; this trait is implemented if and only
+    /// if it is already implemented.
     Cycle(Vec<PredicateObligation<'tcx>>),
     SelectionError(SelectionError<'tcx>),
     ProjectionError(MismatchedProjectionTypes<'tcx>),
     SubtypeError(ExpectedFound<Ty<'tcx>>, TypeError<'tcx>), // always comes from a SubtypePredicate
     ConstEquateError(ExpectedFound<Const<'tcx>>, TypeError<'tcx>),
     Ambiguity {
-        /// Overflow reported from the new solver `-Znext-solver`, which will
-        /// be reported as an regular error as opposed to a fatal error.
-        overflow: bool,
+        /// Overflow is only `Some(suggest_recursion_limit)` when using the next generation
+        /// trait solver `-Znext-solver`. With the old solver overflow is eagerly handled by
+        /// emitting a fatal error instead.
+        overflow: Option<bool>,
     },
 }
 

compiler/rustc_infer/src/traits/structural_impls.rs

@@ -47,8 +47,10 @@ impl<'tcx> fmt::Debug for traits::FulfillmentErrorCode<'tcx> {
             ConstEquateError(ref a, ref b) => {
                 write!(f, "CodeConstEquateError({a:?}, {b:?})")
             }
-            Ambiguity { overflow: false } => write!(f, "Ambiguity"),
-            Ambiguity { overflow: true } => write!(f, "Overflow"),
+            Ambiguity { overflow: None } => write!(f, "Ambiguity"),
+            Ambiguity { overflow: Some(suggest_increasing_limit) } => {
+                write!(f, "Overflow({suggest_increasing_limit})")
+            }
             Cycle(ref cycle) => write!(f, "Cycle({cycle:?})"),
         }
     }

compiler/rustc_lint_defs/src/builtin.rs

@@ -3586,18 +3586,9 @@ declare_lint! {
     /// being validated. Usually these should be rejected as a hard error,
     /// but this lint was introduced to avoid breaking any existing
     /// crates which included them.
-    ///
-    /// This is a [future-incompatible] lint to transition this to a hard
-    /// error in the future. See [issue #82730] for more details.
-    ///
-    /// [issue #82730]: https://github.com/rust-lang/rust/issues/82730
     pub INVALID_DOC_ATTRIBUTES,
-    Warn,
+    Deny,
     "detects invalid `#[doc(...)]` attributes",
-    @future_incompatible = FutureIncompatibleInfo {
-        reason: FutureIncompatibilityReason::FutureReleaseErrorDontReportInDeps,
-        reference: "issue #82730 <https://github.com/rust-lang/rust/issues/82730>",
-    };
 }
 
 declare_lint! {

compiler/rustc_middle/src/traits/solve.rs

@@ -60,7 +60,6 @@ pub enum Certainty {
 
 impl Certainty {
     pub const AMBIGUOUS: Certainty = Certainty::Maybe(MaybeCause::Ambiguity);
-    pub const OVERFLOW: Certainty = Certainty::Maybe(MaybeCause::Overflow);
 
     /// Use this function to merge the certainty of multiple nested subgoals.
     ///
@@ -79,16 +78,13 @@ impl Certainty {
             (Certainty::Yes, Certainty::Yes) => Certainty::Yes,
             (Certainty::Yes, Certainty::Maybe(_)) => other,
             (Certainty::Maybe(_), Certainty::Yes) => self,
-            (Certainty::Maybe(MaybeCause::Ambiguity), Certainty::Maybe(MaybeCause::Ambiguity)) => {
-                Certainty::Maybe(MaybeCause::Ambiguity)
-            }
-            (Certainty::Maybe(MaybeCause::Ambiguity), Certainty::Maybe(MaybeCause::Overflow))
-            | (Certainty::Maybe(MaybeCause::Overflow), Certainty::Maybe(MaybeCause::Ambiguity))
-            | (Certainty::Maybe(MaybeCause::Overflow), Certainty::Maybe(MaybeCause::Overflow)) => {
-                Certainty::Maybe(MaybeCause::Overflow)
-            }
+            (Certainty::Maybe(a), Certainty::Maybe(b)) => Certainty::Maybe(a.unify_with(b)),
         }
     }
+
+    pub const fn overflow(suggest_increasing_limit: bool) -> Certainty {
+        Certainty::Maybe(MaybeCause::Overflow { suggest_increasing_limit })
+    }
 }
 
 /// Why we failed to evaluate a goal.
@@ -99,7 +95,21 @@ pub enum MaybeCause {
     /// or we hit a case where we just don't bother, e.g. `?x: Trait` goals.
     Ambiguity,
     /// We gave up due to an overflow, most often by hitting the recursion limit.
-    Overflow,
+    Overflow { suggest_increasing_limit: bool },
+}
+
+impl MaybeCause {
+    fn unify_with(self, other: MaybeCause) -> MaybeCause {
+        match (self, other) {
+            (MaybeCause::Ambiguity, MaybeCause::Ambiguity) => MaybeCause::Ambiguity,
+            (MaybeCause::Ambiguity, MaybeCause::Overflow { .. }) => other,
+            (MaybeCause::Overflow { .. }, MaybeCause::Ambiguity) => self,
+            (
+                MaybeCause::Overflow { suggest_increasing_limit: a },
+                MaybeCause::Overflow { suggest_increasing_limit: b },
+            ) => MaybeCause::Overflow { suggest_increasing_limit: a || b },
+        }
+    }
 }
 
 #[derive(Debug, PartialEq, Eq, Clone, Copy, Hash, HashStable, TypeFoldable, TypeVisitable)]

compiler/rustc_mir_build/src/build/matches/mod.rs

@@ -1097,21 +1097,18 @@ enum TestKind<'tcx> {
         variants: BitSet<VariantIdx>,
     },
 
-    /// Test what value an integer, `bool`, or `char` has.
+    /// Test what value an integer or `char` has.
     SwitchInt {
-        /// The type of the value that we're testing.
-        switch_ty: Ty<'tcx>,
         /// The (ordered) set of values that we test for.
         ///
-        /// For integers and `char`s we create a branch to each of the values in
-        /// `options`, as well as an "otherwise" branch for all other values, even
-        /// in the (rare) case that `options` is exhaustive.
-        ///
-        /// For `bool` we always generate two edges, one for `true` and one for
-        /// `false`.
+        /// We create a branch to each of the values in `options`, as well as an "otherwise" branch
+        /// for all other values, even in the (rare) case that `options` is exhaustive.
         options: FxIndexMap<Const<'tcx>, u128>,
     },
 
+    /// Test what value a `bool` has.
+    If,
+
     /// Test for equality with value, possibly after an unsizing coercion to
     /// `ty`,
     Eq {
@@ -1617,7 +1614,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         // a test like SwitchInt, we may want to add cases based on the candidates that are
         // available
         match test.kind {
-            TestKind::SwitchInt { switch_ty: _, ref mut options } => {
+            TestKind::SwitchInt { ref mut options } => {
                 for candidate in candidates.iter() {
                     if !self.add_cases_to_switch(&match_place, candidate, options) {
                         break;