Rollup of 6 pull requests

compiler/rustc_ast_lowering/src/expr.rs

@@ -1067,6 +1067,15 @@ impl<'hir> LoweringContext<'_, 'hir> {
         eq_sign_span: Span,
         assignments: &mut Vec<hir::Stmt<'hir>>,
     ) -> &'hir hir::Pat<'hir> {
+        self.arena.alloc(self.destructure_assign_mut(lhs, eq_sign_span, assignments))
+    }
+
+    fn destructure_assign_mut(
+        &mut self,
+        lhs: &Expr,
+        eq_sign_span: Span,
+        assignments: &mut Vec<hir::Stmt<'hir>>,
+    ) -> hir::Pat<'hir> {
         match &lhs.kind {
             // Underscore pattern.
             ExprKind::Underscore => {
@@ -1080,7 +1089,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     let (before, after) = pats.split_at(i);
                     hir::PatKind::Slice(
                         before,
-                        Some(self.pat_without_dbm(span, hir::PatKind::Wild)),
+                        Some(self.arena.alloc(self.pat_without_dbm(span, hir::PatKind::Wild))),
                         after,
                     )
                 } else {
@@ -1165,14 +1174,14 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     let tuple_pat = hir::PatKind::Tuple(&[], Some(0));
                     return self.pat_without_dbm(lhs.span, tuple_pat);
                 } else {
-                    return self.destructure_assign(e, eq_sign_span, assignments);
+                    return self.destructure_assign_mut(e, eq_sign_span, assignments);
                 }
             }
             _ => {}
         }
         // Treat all other cases as normal lvalue.
         let ident = Ident::new(sym::lhs, lhs.span);
-        let (pat, binding) = self.pat_ident(lhs.span, ident);
+        let (pat, binding) = self.pat_ident_mut(lhs.span, ident);
         let ident = self.expr_ident(lhs.span, ident, binding);
         let assign = hir::ExprKind::Assign(self.lower_expr(lhs), ident, eq_sign_span);
         let expr = self.expr(lhs.span, assign, ThinVec::new());
@@ -1191,7 +1200,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         ctx: &str,
         eq_sign_span: Span,
         assignments: &mut Vec<hir::Stmt<'hir>>,
-    ) -> (&'hir [&'hir hir::Pat<'hir>], Option<(usize, Span)>) {
+    ) -> (&'hir [hir::Pat<'hir>], Option<(usize, Span)>) {
         let mut rest = None;
         let elements =
             self.arena.alloc_from_iter(elements.iter().enumerate().filter_map(|(i, e)| {
@@ -1204,7 +1213,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     }
                     None
                 } else {
-                    Some(self.destructure_assign(e, eq_sign_span, assignments))
+                    Some(self.destructure_assign_mut(e, eq_sign_span, assignments))
                 }
             }));
         (elements, rest)

compiler/rustc_ast_lowering/src/lib.rs

@@ -2577,21 +2577,35 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         self.pat_ident_binding_mode(span, ident, hir::BindingAnnotation::Unannotated)
     }
 
+    fn pat_ident_mut(&mut self, span: Span, ident: Ident) -> (hir::Pat<'hir>, hir::HirId) {
+        self.pat_ident_binding_mode_mut(span, ident, hir::BindingAnnotation::Unannotated)
+    }
+
     fn pat_ident_binding_mode(
         &mut self,
         span: Span,
         ident: Ident,
         bm: hir::BindingAnnotation,
     ) -> (&'hir hir::Pat<'hir>, hir::HirId) {
+        let (pat, hir_id) = self.pat_ident_binding_mode_mut(span, ident, bm);
+        (self.arena.alloc(pat), hir_id)
+    }
+
+    fn pat_ident_binding_mode_mut(
+        &mut self,
+        span: Span,
+        ident: Ident,
+        bm: hir::BindingAnnotation,
+    ) -> (hir::Pat<'hir>, hir::HirId) {
         let hir_id = self.next_id();
 
         (
-            self.arena.alloc(hir::Pat {
+            hir::Pat {
                 hir_id,
                 kind: hir::PatKind::Binding(bm, hir_id, ident.with_span_pos(span), None),
                 span,
                 default_binding_modes: true,
-            }),
+            },
             hir_id,
         )
     }
@@ -2609,13 +2623,8 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         })
     }
 
-    fn pat_without_dbm(&mut self, span: Span, kind: hir::PatKind<'hir>) -> &'hir hir::Pat<'hir> {
-        self.arena.alloc(hir::Pat {
-            hir_id: self.next_id(),
-            kind,
-            span,
-            default_binding_modes: false,
-        })
+    fn pat_without_dbm(&mut self, span: Span, kind: hir::PatKind<'hir>) -> hir::Pat<'hir> {
+        hir::Pat { hir_id: self.next_id(), kind, span, default_binding_modes: false }
     }
 
     fn ty_path(

compiler/rustc_ast_lowering/src/pat.rs

@@ -10,7 +10,11 @@ use rustc_span::symbol::Ident;
 use rustc_span::{source_map::Spanned, Span};
 
 impl<'a, 'hir> LoweringContext<'a, 'hir> {
-    crate fn lower_pat(&mut self, mut pattern: &Pat) -> &'hir hir::Pat<'hir> {
+    crate fn lower_pat(&mut self, pattern: &Pat) -> &'hir hir::Pat<'hir> {
+        self.arena.alloc(self.lower_pat_mut(pattern))
+    }
+
+    crate fn lower_pat_mut(&mut self, mut pattern: &Pat) -> hir::Pat<'hir> {
         ensure_sufficient_stack(|| {
             // loop here to avoid recursion
             let node = loop {
@@ -34,7 +38,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                     }
                     PatKind::Or(ref pats) => {
                         break hir::PatKind::Or(
-                            self.arena.alloc_from_iter(pats.iter().map(|x| self.lower_pat(x))),
+                            self.arena.alloc_from_iter(pats.iter().map(|x| self.lower_pat_mut(x))),
                         );
                     }
                     PatKind::Path(ref qself, ref path) => {
@@ -101,7 +105,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         &mut self,
         pats: &[P<Pat>],
         ctx: &str,
-    ) -> (&'hir [&'hir hir::Pat<'hir>], Option<usize>) {
+    ) -> (&'hir [hir::Pat<'hir>], Option<usize>) {
         let mut elems = Vec::with_capacity(pats.len());
         let mut rest = None;
 
@@ -140,7 +144,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             }
 
             // It was not a sub-tuple pattern so lower it normally.
-            elems.push(self.lower_pat(pat));
+            elems.push(self.lower_pat_mut(pat));
         }
 
         for (_, pat) in iter {
@@ -149,7 +153,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                 // ...but there was one again, so error.
                 self.ban_extra_rest_pat(pat.span, rest.unwrap().1, ctx);
             } else {
-                elems.push(self.lower_pat(pat));
+                elems.push(self.lower_pat_mut(pat));
             }
         }
 
@@ -189,11 +193,11 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                 // Record, lower it to `$binding_mode $ident @ _`, and stop here.
                 PatKind::Ident(ref bm, ident, Some(ref sub)) if sub.is_rest() => {
                     prev_rest_span = Some(sub.span);
-                    slice = Some(lower_rest_sub(self, pat, bm, ident, sub));
+                    slice = Some(self.arena.alloc(lower_rest_sub(self, pat, bm, ident, sub)));
                     break;
                 }
                 // It was not a subslice pattern so lower it normally.
-                _ => before.push(self.lower_pat(pat)),
+                _ => before.push(self.lower_pat_mut(pat)),
             }
         }
 
@@ -214,7 +218,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                 self.ban_extra_rest_pat(rest_span, prev_rest_span.unwrap(), "slice");
             } else {
                 // Lower the pattern normally.
-                after.push(self.lower_pat(pat));
+                after.push(self.lower_pat_mut(pat));
             }
         }
 
@@ -268,17 +272,17 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
     }
 
     fn pat_wild_with_node_id_of(&mut self, p: &Pat) -> &'hir hir::Pat<'hir> {
-        self.pat_with_node_id_of(p, hir::PatKind::Wild)
+        self.arena.alloc(self.pat_with_node_id_of(p, hir::PatKind::Wild))
     }
 
     /// Construct a `Pat` with the `HirId` of `p.id` lowered.
-    fn pat_with_node_id_of(&mut self, p: &Pat, kind: hir::PatKind<'hir>) -> &'hir hir::Pat<'hir> {
-        self.arena.alloc(hir::Pat {
+    fn pat_with_node_id_of(&mut self, p: &Pat, kind: hir::PatKind<'hir>) -> hir::Pat<'hir> {
+        hir::Pat {
             hir_id: self.lower_node_id(p.id),
             kind,
             span: p.span,
             default_binding_modes: true,
-        })
+        }
     }
 
     /// Emit a friendly error for extra `..` patterns in a tuple/tuple struct/slice pattern.

compiler/rustc_hir/src/hir.rs

@@ -808,13 +808,13 @@ impl<'hir> Pat<'hir> {
         }
 
         use PatKind::*;
-        match &self.kind {
+        match self.kind {
             Wild | Lit(_) | Range(..) | Binding(.., None) | Path(_) => true,
             Box(s) | Ref(s, _) | Binding(.., Some(s)) => s.walk_short_(it),
             Struct(_, fields, _) => fields.iter().all(|field| field.pat.walk_short_(it)),
             TupleStruct(_, s, _) | Tuple(s, _) | Or(s) => s.iter().all(|p| p.walk_short_(it)),
             Slice(before, slice, after) => {
-                before.iter().chain(slice.iter()).chain(after.iter()).all(|p| p.walk_short_(it))
+                before.iter().chain(slice).chain(after.iter()).all(|p| p.walk_short_(it))
             }
         }
     }
@@ -836,13 +836,13 @@ impl<'hir> Pat<'hir> {
         }
 
         use PatKind::*;
-        match &self.kind {
+        match self.kind {
             Wild | Lit(_) | Range(..) | Binding(.., None) | Path(_) => {}
             Box(s) | Ref(s, _) | Binding(.., Some(s)) => s.walk_(it),
             Struct(_, fields, _) => fields.iter().for_each(|field| field.pat.walk_(it)),
             TupleStruct(_, s, _) | Tuple(s, _) | Or(s) => s.iter().for_each(|p| p.walk_(it)),
             Slice(before, slice, after) => {
-                before.iter().chain(slice.iter()).chain(after.iter()).for_each(|p| p.walk_(it))
+                before.iter().chain(slice).chain(after.iter()).for_each(|p| p.walk_(it))
             }
         }
     }
@@ -940,19 +940,19 @@ pub enum PatKind<'hir> {
     /// A tuple struct/variant pattern `Variant(x, y, .., z)`.
     /// If the `..` pattern fragment is present, then `Option<usize>` denotes its position.
     /// `0 <= position <= subpats.len()`
-    TupleStruct(QPath<'hir>, &'hir [&'hir Pat<'hir>], Option<usize>),
+    TupleStruct(QPath<'hir>, &'hir [Pat<'hir>], Option<usize>),
 
     /// An or-pattern `A | B | C`.
     /// Invariant: `pats.len() >= 2`.
-    Or(&'hir [&'hir Pat<'hir>]),
+    Or(&'hir [Pat<'hir>]),
 
     /// A path pattern for an unit struct/variant or a (maybe-associated) constant.
     Path(QPath<'hir>),
 
     /// A tuple pattern (e.g., `(a, b)`).
     /// If the `..` pattern fragment is present, then `Option<usize>` denotes its position.
     /// `0 <= position <= subpats.len()`
-    Tuple(&'hir [&'hir Pat<'hir>], Option<usize>),
+    Tuple(&'hir [Pat<'hir>], Option<usize>),
 
     /// A `box` pattern.
     Box(&'hir Pat<'hir>),
@@ -975,7 +975,7 @@ pub enum PatKind<'hir> {
     /// ```
     /// PatKind::Slice([Binding(a), Binding(b)], Some(Wild), [Binding(c), Binding(d)])
     /// ```
-    Slice(&'hir [&'hir Pat<'hir>], Option<&'hir Pat<'hir>>, &'hir [&'hir Pat<'hir>]),
+    Slice(&'hir [Pat<'hir>], Option<&'hir Pat<'hir>>, &'hir [Pat<'hir>]),
 }
 
 #[derive(Copy, Clone, PartialEq, Encodable, Debug, HashStable_Generic)]

compiler/rustc_lint/src/levels.rs

@@ -26,8 +26,6 @@ use rustc_span::symbol::{sym, Symbol};
 use rustc_span::{source_map::MultiSpan, Span, DUMMY_SP};
 use tracing::debug;
 
-use std::cmp;
-
 fn lint_levels(tcx: TyCtxt<'_>, (): ()) -> LintLevelMap {
     let store = unerased_lint_store(tcx);
     let crate_attrs = tcx.hir().attrs(CRATE_HIR_ID);
@@ -91,36 +89,24 @@ impl<'s> LintLevelsBuilder<'s> {
         for &(ref lint_name, level) in &sess.opts.lint_opts {
             store.check_lint_name_cmdline(sess, &lint_name, level, self.crate_attrs);
             let orig_level = level;
-
-            // If the cap is less than this specified level, e.g., if we've got
-            // `--cap-lints allow` but we've also got `-D foo` then we ignore
-            // this specification as the lint cap will set it to allow anyway.
-            let level = cmp::min(level, self.sets.lint_cap);
-
             let lint_flag_val = Symbol::intern(lint_name);
 
             let ids = match store.find_lints(&lint_name) {
                 Ok(ids) => ids,
                 Err(_) => continue, // errors handled in check_lint_name_cmdline above
             };
             for id in ids {
+                // ForceWarn and Forbid cannot be overriden
+                if let Some((Level::ForceWarn | Level::Forbid, _)) = specs.get(&id) {
+                    continue;
+                }
+
                 self.check_gated_lint(id, DUMMY_SP);
                 let src = LintLevelSource::CommandLine(lint_flag_val, orig_level);
                 specs.insert(id, (level, src));
             }
         }
 
-        for lint_name in &sess.opts.force_warns {
-            store.check_lint_name_cmdline(sess, lint_name, Level::ForceWarn, self.crate_attrs);
-            let lints = store
-                .find_lints(lint_name)
-                .unwrap_or_else(|_| bug!("A valid lint failed to produce a lint ids"));
-            for id in lints {
-                let src = LintLevelSource::CommandLine(Symbol::intern(lint_name), Level::ForceWarn);
-                specs.insert(id, (Level::ForceWarn, src));
-            }
-        }
-
         self.cur = self.sets.list.push(LintSet { specs, parent: COMMAND_LINE });
     }
 

compiler/rustc_middle/src/ty/layout.rs

@@ -312,7 +312,8 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
         let dl = self.data_layout();
         let pack = repr.pack;
         if pack.is_some() && repr.align.is_some() {
-            bug!("struct cannot be packed and aligned");
+            self.tcx.sess.delay_span_bug(DUMMY_SP, "struct cannot be packed and aligned");
+            return Err(LayoutError::Unknown(ty));
         }
 
         let mut align = if pack.is_some() { dl.i8_align } else { dl.aggregate_align };
@@ -808,7 +809,11 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
 
                 if def.is_union() {
                     if def.repr.pack.is_some() && def.repr.align.is_some() {
-                        bug!("union cannot be packed and aligned");
+                        self.tcx.sess.delay_span_bug(
+                            tcx.def_span(def.did),
+                            "union cannot be packed and aligned",
+                        );
+                        return Err(LayoutError::Unknown(ty));
                     }
 
                     let mut align =

compiler/rustc_mir_build/src/thir/pattern/mod.rs

@@ -325,7 +325,7 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> {
 
     fn lower_tuple_subpats(
         &mut self,
-        pats: &'tcx [&'tcx hir::Pat<'tcx>],
+        pats: &'tcx [hir::Pat<'tcx>],
         expected_len: usize,
         gap_pos: Option<usize>,
     ) -> Vec<FieldPat<'tcx>> {
@@ -338,7 +338,7 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> {
             .collect()
     }
 
-    fn lower_patterns(&mut self, pats: &'tcx [&'tcx hir::Pat<'tcx>]) -> Vec<Pat<'tcx>> {
+    fn lower_patterns(&mut self, pats: &'tcx [hir::Pat<'tcx>]) -> Vec<Pat<'tcx>> {
         pats.iter().map(|p| self.lower_pattern(p)).collect()
     }
 
@@ -350,9 +350,9 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> {
         &mut self,
         span: Span,
         ty: Ty<'tcx>,
-        prefix: &'tcx [&'tcx hir::Pat<'tcx>],
+        prefix: &'tcx [hir::Pat<'tcx>],
         slice: &'tcx Option<&'tcx hir::Pat<'tcx>>,
-        suffix: &'tcx [&'tcx hir::Pat<'tcx>],
+        suffix: &'tcx [hir::Pat<'tcx>],
     ) -> PatKind<'tcx> {
         let prefix = self.lower_patterns(prefix);
         let slice = self.lower_opt_pattern(slice);