Rollup of 8 pull requests

compiler/rustc_hir_pretty/src/lib.rs

@@ -1138,9 +1138,7 @@ impl<'a> State<'a> {
     fn print_expr_anon_const(&mut self, anon_const: &hir::AnonConst) {
         self.ibox(INDENT_UNIT);
         self.s.word_space("const");
-        self.s.word("{");
         self.print_anon_const(anon_const);
-        self.s.word("}");
         self.end()
     }
 

compiler/rustc_middle/src/mir/mod.rs

@@ -821,9 +821,6 @@ pub struct LocalDecl<'tcx> {
     /// flag drop flags to avoid triggering this check as they are introduced
     /// after typeck.
     ///
-    /// Unsafety checking will also ignore dereferences of these locals,
-    /// so they can be used for raw pointers only used in a desugaring.
-    ///
     /// This should be sound because the drop flags are fully algebraic, and
     /// therefore don't affect the OIBIT or outlives properties of the
     /// generator.
@@ -1010,13 +1007,13 @@ impl<'tcx> LocalDecl<'tcx> {
     }
 
     /// Returns `Some` if this is a reference to a static item that is used to
-    /// access that static
+    /// access that static.
     pub fn is_ref_to_static(&self) -> bool {
         matches!(self.local_info, Some(box LocalInfo::StaticRef { .. }))
     }
 
-    /// Returns `Some` if this is a reference to a static item that is used to
-    /// access that static
+    /// Returns `Some` if this is a reference to a thread-local static item that is used to
+    /// access that static.
     pub fn is_ref_to_thread_local(&self) -> bool {
         match self.local_info {
             Some(box LocalInfo::StaticRef { is_thread_local, .. }) => is_thread_local,

compiler/rustc_middle/src/mir/tcx.rs

@@ -152,10 +152,14 @@ impl<'tcx> Rvalue<'tcx> {
                 tcx.mk_ty(ty::Array(operand.ty(local_decls, tcx), count))
             }
             Rvalue::ThreadLocalRef(did) => {
+                let static_ty = tcx.type_of(did);
                 if tcx.is_mutable_static(did) {
-                    tcx.mk_mut_ptr(tcx.type_of(did))
+                    tcx.mk_mut_ptr(static_ty)
+                } else if tcx.is_foreign_item(did) {
+                    tcx.mk_imm_ptr(static_ty)
                 } else {
-                    tcx.mk_imm_ref(tcx.lifetimes.re_static, tcx.type_of(did))
+                    // FIXME: These things don't *really* have 'static lifetime.
+                    tcx.mk_imm_ref(tcx.lifetimes.re_static, static_ty)
                 }
             }
             Rvalue::Ref(reg, bk, ref place) => {

compiler/rustc_middle/src/ty/util.rs

@@ -529,8 +529,12 @@ impl<'tcx> TyCtxt<'tcx> {
         // Make sure that any constants in the static's type are evaluated.
         let static_ty = self.normalize_erasing_regions(ty::ParamEnv::empty(), self.type_of(def_id));
 
+        // Make sure that accesses to unsafe statics end up using raw pointers.
+        // For thread-locals, this needs to be kept in sync with `Rvalue::ty`.
         if self.is_mutable_static(def_id) {
             self.mk_mut_ptr(static_ty)
+        } else if self.is_foreign_item(def_id) {
+            self.mk_imm_ptr(static_ty)
         } else {
             self.mk_imm_ref(self.lifetimes.re_erased, static_ty)
         }

compiler/rustc_mir/src/transform/check_unsafety.rs

@@ -204,6 +204,9 @@ impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> {
             if let [] = proj_base {
                 let decl = &self.body.local_decls[place.local];
                 if decl.internal {
+                    // If the projection root is an artifical local that we introduced when
+                    // desugaring `static`, give a more specific error message
+                    // (avoid the general "raw pointer" clause below, that would only be confusing).
                     if let Some(box LocalInfo::StaticRef { def_id, .. }) = decl.local_info {
                         if self.tcx.is_mutable_static(def_id) {
                             self.require_unsafe(

compiler/rustc_parse/src/parser/mod.rs

@@ -548,7 +548,11 @@ impl<'a> Parser<'a> {
 
     fn check_inline_const(&mut self) -> bool {
         self.check_keyword(kw::Const)
-            && self.look_ahead(1, |t| t == &token::OpenDelim(DelimToken::Brace))
+            && self.look_ahead(1, |t| match t.kind {
+                token::Interpolated(ref nt) => matches!(**nt, token::NtBlock(..)),
+                token::OpenDelim(DelimToken::Brace) => true,
+                _ => false,
+            })
     }
 
     /// Checks to see if the next token is either `+` or `+=`.

compiler/rustc_passes/src/liveness.rs

@@ -1174,7 +1174,7 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> {
                             }
                         }
                         hir::InlineAsmOperand::InOut { expr, .. } => {
-                            succ = self.write_place(expr, succ, ACC_READ | ACC_WRITE);
+                            succ = self.write_place(expr, succ, ACC_READ | ACC_WRITE | ACC_USE);
                         }
                         hir::InlineAsmOperand::SplitInOut { out_expr, .. } => {
                             if let Some(expr) = out_expr {

compiler/rustc_typeck/src/check/op.rs

@@ -302,7 +302,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                 true,
                             ),
                             hir::BinOpKind::Mul => (
-                                format!("cannot multiply `{}` to `{}`", rhs_ty, lhs_ty),
+                                format!("cannot multiply `{}` by `{}`", lhs_ty, rhs_ty),
                                 Some("std::ops::Mul"),
                                 true,
                             ),

library/alloc/src/collections/btree/map.rs

@@ -13,8 +13,6 @@ use super::node::{self, marker, ForceResult::*, Handle, NodeRef};
 use super::search::{self, SearchResult::*};
 use super::unwrap_unchecked;
 
-use UnderflowResult::*;
-
 mod entry;
 pub use entry::{Entry, OccupiedEntry, VacantEntry};
 use Entry::*;
@@ -1154,40 +1152,8 @@ impl<K: Ord, V> BTreeMap<K, V> {
 
         let mut right = Self::new();
         let right_root = Self::ensure_is_owned(&mut right.root);
-        for _ in 0..left_root.height() {
-            right_root.push_internal_level();
-        }
-
-        {
-            let mut left_node = left_root.node_as_mut();
-            let mut right_node = right_root.node_as_mut();
-
-            loop {
-                let mut split_edge = match search::search_node(left_node, key) {
-                    // key is going to the right tree
-                    Found(handle) => handle.left_edge(),
-                    GoDown(handle) => handle,
-                };
 
-                split_edge.move_suffix(&mut right_node);
-
-                match (split_edge.force(), right_node.force()) {
-                    (Internal(edge), Internal(node)) => {
-                        left_node = edge.descend();
-                        right_node = node.first_edge().descend();
-                    }
-                    (Leaf(_), Leaf(_)) => {
-                        break;
-                    }
-                    _ => {
-                        unreachable!();
-                    }
-                }
-            }
-        }
-
-        left_root.fix_right_border();
-        right_root.fix_left_border();
+        left_root.split_off(right_root, key);
 
         if left_root.height() < right_root.height() {
             self.length = left_root.node_as_ref().calc_length();
@@ -2250,193 +2216,6 @@ impl<K, V> BTreeMap<K, V> {
     }
 }
 
-impl<'a, K: 'a, V: 'a> Handle<NodeRef<marker::Mut<'a>, K, V, marker::LeafOrInternal>, marker::KV> {
-    /// Removes a key/value-pair from the map, and returns that pair, as well as
-    /// the leaf edge corresponding to that former pair.
-    fn remove_kv_tracking<F: FnOnce()>(
-        self,
-        handle_emptied_internal_root: F,
-    ) -> ((K, V), Handle<NodeRef<marker::Mut<'a>, K, V, marker::Leaf>, marker::Edge>) {
-        let (old_kv, mut pos, was_internal) = match self.force() {
-            Leaf(leaf) => {
-                let (old_kv, pos) = leaf.remove();
-                (old_kv, pos, false)
-            }
-            Internal(mut internal) => {
-                // Replace the location freed in the internal node with an
-                // adjacent KV, and remove that adjacent KV from its leaf.
-                // Always choose the adjacent KV on the left side because
-                // it is typically faster to pop an element from the end
-                // of the KV arrays without needing to shift other elements.
-
-                let key_loc = internal.kv_mut().0 as *mut K;
-                let val_loc = internal.kv_mut().1 as *mut V;
-
-                let to_remove = internal.left_edge().descend().last_leaf_edge().left_kv().ok();
-                let to_remove = unsafe { unwrap_unchecked(to_remove) };
-
-                let (kv, pos) = to_remove.remove();
-
-                let old_key = unsafe { mem::replace(&mut *key_loc, kv.0) };
-                let old_val = unsafe { mem::replace(&mut *val_loc, kv.1) };
-
-                ((old_key, old_val), pos, true)
-            }
-        };
-
-        // Handle underflow
-        let mut cur_node = unsafe { ptr::read(&pos).into_node().forget_type() };
-        let mut at_leaf = true;
-        while cur_node.len() < node::MIN_LEN {
-            match handle_underfull_node(cur_node) {
-                AtRoot => break,
-                Merged(edge, merged_with_left, offset) => {
-                    // If we merged with our right sibling then our tracked
-                    // position has not changed. However if we merged with our
-                    // left sibling then our tracked position is now dangling.
-                    if at_leaf && merged_with_left {
-                        let idx = pos.idx() + offset;
-                        let node = match unsafe { ptr::read(&edge).descend().force() } {
-                            Leaf(leaf) => leaf,
-                            Internal(_) => unreachable!(),
-                        };
-                        pos = unsafe { Handle::new_edge(node, idx) };
-                    }
-
-                    let parent = edge.into_node();
-                    if parent.len() == 0 {
-                        // The parent that was just emptied must be the root,
-                        // because nodes on a lower level would not have been
-                        // left with a single child.
-                        handle_emptied_internal_root();
-                        break;
-                    } else {
-                        cur_node = parent.forget_type();
-                        at_leaf = false;
-                    }
-                }
-                Stole(stole_from_left) => {
-                    // Adjust the tracked position if we stole from a left sibling
-                    if stole_from_left && at_leaf {
-                        // SAFETY: This is safe since we just added an element to our node.
-                        unsafe {
-                            pos.move_next_unchecked();
-                        }
-                    }
-                    break;
-                }
-            }
-        }
-
-        // If we deleted from an internal node then we need to compensate for
-        // the earlier swap and adjust the tracked position to point to the
-        // next element.
-        if was_internal {
-            pos = unsafe { unwrap_unchecked(pos.next_kv().ok()).next_leaf_edge() };
-        }
-
-        (old_kv, pos)
-    }
-}
-
-impl<K, V> node::Root<K, V> {
-    /// Removes empty levels on the top, but keep an empty leaf if the entire tree is empty.
-    fn fix_top(&mut self) {
-        while self.height() > 0 && self.node_as_ref().len() == 0 {
-            self.pop_internal_level();
-        }
-    }
-
-    fn fix_right_border(&mut self) {
-        self.fix_top();
-
-        {
-            let mut cur_node = self.node_as_mut();
-
-            while let Internal(node) = cur_node.force() {
-                let mut last_kv = node.last_kv();
-
-                if last_kv.can_merge() {
-                    cur_node = last_kv.merge().descend();
-                } else {
-                    let right_len = last_kv.reborrow().right_edge().descend().len();
-                    // `MINLEN + 1` to avoid readjust if merge happens on the next level.
-                    if right_len < node::MIN_LEN + 1 {
-                        last_kv.bulk_steal_left(node::MIN_LEN + 1 - right_len);
-                    }
-                    cur_node = last_kv.right_edge().descend();
-                }
-            }
-        }
-
-        self.fix_top();
-    }
-
-    /// The symmetric clone of `fix_right_border`.
-    fn fix_left_border(&mut self) {
-        self.fix_top();
-
-        {
-            let mut cur_node = self.node_as_mut();
-
-            while let Internal(node) = cur_node.force() {
-                let mut first_kv = node.first_kv();
-
-                if first_kv.can_merge() {
-                    cur_node = first_kv.merge().descend();
-                } else {
-                    let left_len = first_kv.reborrow().left_edge().descend().len();
-                    if left_len < node::MIN_LEN + 1 {
-                        first_kv.bulk_steal_right(node::MIN_LEN + 1 - left_len);
-                    }
-                    cur_node = first_kv.left_edge().descend();
-                }
-            }
-        }
-
-        self.fix_top();
-    }
-}
-
-enum UnderflowResult<'a, K, V> {
-    AtRoot,
-    Merged(Handle<NodeRef<marker::Mut<'a>, K, V, marker::Internal>, marker::Edge>, bool, usize),
-    Stole(bool),
-}
-
-fn handle_underfull_node<'a, K: 'a, V: 'a>(
-    node: NodeRef<marker::Mut<'a>, K, V, marker::LeafOrInternal>,
-) -> UnderflowResult<'_, K, V> {
-    let parent = match node.ascend() {
-        Ok(parent) => parent,
-        Err(_) => return AtRoot,
-    };
-
-    // Prefer the left KV if it exists. Merging with the left side is faster,
-    // since merging happens towards the left and `node` has fewer elements.
-    // Stealing from the left side is faster, since we can pop from the end of
-    // the KV arrays.
-    let (is_left, mut handle) = match parent.left_kv() {
-        Ok(left) => (true, left),
-        Err(parent) => {
-            let right = unsafe { unwrap_unchecked(parent.right_kv().ok()) };
-            (false, right)
-        }
-    };
-
-    if handle.can_merge() {
-        let offset = if is_left { handle.reborrow().left_edge().descend().len() + 1 } else { 0 };
-        Merged(handle.merge(), is_left, offset)
-    } else {
-        if is_left {
-            handle.steal_left();
-        } else {
-            handle.steal_right();
-        }
-        Stole(is_left)
-    }
-}
-
 impl<K: Ord, V, I: Iterator<Item = (K, V)>> Iterator for MergeIter<K, V, I> {
     type Item = (K, V);
 

library/alloc/src/collections/btree/mod.rs

@@ -2,8 +2,10 @@ mod borrow;
 pub mod map;
 mod navigate;
 mod node;
+mod remove;
 mod search;
 pub mod set;
+mod split;
 
 #[doc(hidden)]
 trait Recover<Q: ?Sized> {