Auto merge of #132251 - jieyouxu:rollup-mtv9mpd, r=jieyouxu

Rollup of 7 pull requests

Successful merges:

 - #131633 (error on alignments greater than `isize::MAX`)
 - #132086 (Tweak E0277 highlighting and "long type" path printing)
 - #132220 (Add GUI regression test for doc struct fields margins)
 - #132225 (Dynamically link run-make support)
 - #132227 (Pass constness with span into lower_poly_trait_ref)
 - #132242 (Support `char::is_digit` in const contexts.)
 - #132243 (Remove `ObligationCause::span()` method)

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

Author: bors

compiler/rustc_hir_analysis/src/check/compare_impl_item.rs

@@ -611,7 +611,7 @@ pub(super) fn collect_return_position_impl_trait_in_trait_tys<'tcx>(
         Err(terr) => {
             let mut diag = struct_span_code_err!(
                 tcx.dcx(),
-                cause.span(),
+                cause.span,
                 E0053,
                 "method `{}` has an incompatible return type for trait",
                 trait_m.name
@@ -1169,7 +1169,7 @@ fn extract_spans_for_error_reporting<'tcx>(
         TypeError::ArgumentMutability(i) | TypeError::ArgumentSorts(ExpectedFound { .. }, i) => {
             (impl_args.nth(i).unwrap(), trait_args.and_then(|mut args| args.nth(i)))
         }
-        _ => (cause.span(), tcx.hir().span_if_local(trait_m.def_id)),
+        _ => (cause.span, tcx.hir().span_if_local(trait_m.def_id)),
     }
 }
 

compiler/rustc_hir_analysis/src/check/mod.rs

@@ -612,7 +612,7 @@ pub fn check_function_signature<'tcx>(
         match err {
             TypeError::ArgumentMutability(i)
             | TypeError::ArgumentSorts(ExpectedFound { .. }, i) => args.nth(i).unwrap(),
-            _ => cause.span(),
+            _ => cause.span,
         }
     }
 

compiler/rustc_hir_analysis/src/hir_ty_lowering/bounds.rs

@@ -168,13 +168,6 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             match hir_bound {
                 hir::GenericBound::Trait(poly_trait_ref) => {
                     let hir::TraitBoundModifiers { constness, polarity } = poly_trait_ref.modifiers;
-                    // FIXME: We could pass these directly into `lower_poly_trait_ref`
-                    // so that we could use these spans in diagnostics within that function...
-                    let constness = match constness {
-                        hir::BoundConstness::Never => None,
-                        hir::BoundConstness::Always(_) => Some(ty::BoundConstness::Const),
-                        hir::BoundConstness::Maybe(_) => Some(ty::BoundConstness::ConstIfConst),
-                    };
                     let polarity = match polarity {
                         rustc_ast::BoundPolarity::Positive => ty::PredicatePolarity::Positive,
                         rustc_ast::BoundPolarity::Negative(_) => ty::PredicatePolarity::Negative,

compiler/rustc_hir_analysis/src/hir_ty_lowering/dyn_compatibility.rs

@@ -50,7 +50,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             } = self.lower_poly_trait_ref(
                 &trait_bound.trait_ref,
                 trait_bound.span,
-                None,
+                hir::BoundConstness::Never,
                 ty::PredicatePolarity::Positive,
                 dummy_self,
                 &mut bounds,

compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs

@@ -658,7 +658,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
         &self,
         trait_ref: &hir::TraitRef<'tcx>,
         span: Span,
-        constness: Option<ty::BoundConstness>,
+        constness: hir::BoundConstness,
         polarity: ty::PredicatePolarity,
         self_ty: Ty<'tcx>,
         bounds: &mut Bounds<'tcx>,
@@ -681,11 +681,11 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             Some(self_ty),
         );
 
-        if let Some(constness) = constness
+        if let hir::BoundConstness::Always(span) | hir::BoundConstness::Maybe(span) = constness
             && !self.tcx().is_const_trait(trait_def_id)
         {
             self.dcx().emit_err(crate::errors::ConstBoundForNonConstTrait {
-                span: trait_ref.path.span,
+                span,
                 modifier: constness.as_str(),
             });
         }
@@ -708,7 +708,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
                 bounds.push_trait_bound(tcx, poly_trait_ref, span, polarity);
 
                 match constness {
-                    Some(ty::BoundConstness::Const) => {
+                    hir::BoundConstness::Always(span) => {
                         if polarity == ty::PredicatePolarity::Positive {
                             bounds.push_const_bound(
                                 tcx,
@@ -718,13 +718,13 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
                             );
                         }
                     }
-                    Some(ty::BoundConstness::ConstIfConst) => {
+                    hir::BoundConstness::Maybe(_) => {
                         // We don't emit a const bound here, since that would mean that we
                         // unconditionally need to prove a `HostEffect` predicate, even when
                         // the predicates are being instantiated in a non-const context. This
                         // is instead handled in the `const_conditions` query.
                     }
-                    None => {}
+                    hir::BoundConstness::Never => {}
                 }
             }
             // On the flip side, when filtering `ConstIfConst` bounds, we only need to convert
@@ -734,12 +734,12 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             // here because we only call this on self bounds, and deal with the recursive case
             // in `lower_assoc_item_constraint`.
             PredicateFilter::ConstIfConst | PredicateFilter::SelfConstIfConst => match constness {
-                Some(ty::BoundConstness::ConstIfConst) => {
+                hir::BoundConstness::Maybe(span) => {
                     if polarity == ty::PredicatePolarity::Positive {
                         bounds.push_const_bound(tcx, poly_trait_ref, ty::HostPolarity::Maybe, span);
                     }
                 }
-                None | Some(ty::BoundConstness::Const) => {}
+                hir::BoundConstness::Always(_) | hir::BoundConstness::Never => {}
             },
         }
 

compiler/rustc_hir_typeck/src/_match.rs

@@ -94,14 +94,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 (None, arm.body.span)
             };
 
-            let (span, code) = match prior_arm {
+            let code = match prior_arm {
                 // The reason for the first arm to fail is not that the match arms diverge,
                 // but rather that there's a prior obligation that doesn't hold.
-                None => {
-                    (arm_span, ObligationCauseCode::BlockTailExpression(arm.body.hir_id, match_src))
-                }
-                Some((prior_arm_block_id, prior_arm_ty, prior_arm_span)) => (
-                    expr.span,
+                None => ObligationCauseCode::BlockTailExpression(arm.body.hir_id, match_src),
+                Some((prior_arm_block_id, prior_arm_ty, prior_arm_span)) => {
                     ObligationCauseCode::MatchExpressionArm(Box::new(MatchExpressionArmCause {
                         arm_block_id,
                         arm_span,
@@ -110,13 +107,14 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         prior_arm_ty,
                         prior_arm_span,
                         scrut_span: scrut.span,
+                        expr_span: expr.span,
                         source: match_src,
                         prior_non_diverging_arms: prior_non_diverging_arms.clone(),
                         tail_defines_return_position_impl_trait,
-                    })),
-                ),
+                    }))
+                }
             };
-            let cause = self.cause(span, code);
+            let cause = self.cause(arm_span, code);
 
             // This is the moral equivalent of `coercion.coerce(self, cause, arm.body, arm_ty)`.
             // We use it this way to be able to expand on the potential error and detect when a

compiler/rustc_hir_typeck/src/expr.rs

@@ -2027,7 +2027,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                     }
                                     Err(_) => {
                                         span_bug!(
-                                            cause.span(),
+                                            cause.span,
                                             "subtyping remaining fields of type changing FRU failed: {target_ty} != {fru_ty}: {}::{}",
                                             variant.name,
                                             ident.name,

compiler/rustc_hir_typeck/src/method/confirm.rs

@@ -550,7 +550,7 @@ impl<'a, 'tcx> ConfirmContext<'a, 'tcx> {
                     // This has/will have errored in wfcheck, which we cannot depend on from here, as typeck on functions
                     // may run before wfcheck if the function is used in const eval.
                     self.dcx().span_delayed_bug(
-                        cause.span(),
+                        cause.span,
                         format!("{self_ty} was a subtype of {method_self_ty} but now is not?"),
                     );
                 }

compiler/rustc_middle/src/traits/mod.rs

@@ -92,16 +92,6 @@ impl<'tcx> ObligationCause<'tcx> {
         ObligationCause { span, body_id: CRATE_DEF_ID, code: Default::default() }
     }
 
-    pub fn span(&self) -> Span {
-        match *self.code() {
-            ObligationCauseCode::MatchExpressionArm(box MatchExpressionArmCause {
-                arm_span,
-                ..
-            }) => arm_span,
-            _ => self.span,
-        }
-    }
-
     #[inline]
     pub fn code(&self) -> &ObligationCauseCode<'tcx> {
         &self.code
@@ -517,10 +507,17 @@ pub struct MatchExpressionArmCause<'tcx> {
     pub prior_arm_block_id: Option<HirId>,
     pub prior_arm_ty: Ty<'tcx>,
     pub prior_arm_span: Span,
+    /// Span of the scrutinee of the match (the matched value).
     pub scrut_span: Span,
+    /// Source of the match, i.e. `match` or a desugaring.
     pub source: hir::MatchSource,
+    /// Span of the *whole* match expr.
+    pub expr_span: Span,
+    /// Spans of the previous arms except for those that diverge (i.e. evaluate to `!`).
+    ///
+    /// These are used for pointing out errors that may affect several arms.
     pub prior_non_diverging_arms: Vec<Span>,
-    // Is the expectation of this match expression an RPIT?
+    /// Is the expectation of this match expression an RPIT?
     pub tail_defines_return_position_impl_trait: Option<LocalDefId>,
 }
 

compiler/rustc_passes/messages.ftl

@@ -622,6 +622,10 @@ passes_remove_fields =
 passes_repr_align_function =
     `repr(align)` attributes on functions are unstable
 
+passes_repr_align_greater_than_target_max =
+    alignment must not be greater than `isize::MAX` bytes
+    .note = `isize::MAX` is {$size} for the current target
+
 passes_repr_conflicting =
     conflicting representation hints