Auto merge of #122045 - matthiaskrgr:rollup-5l3vpn7, r=matthiaskrgr

Rollup of 9 pull requests

Successful merges:

 - #121065 (Add basic i18n guidance for `Display`)
 - #121744 (Stop using Bubble in coherence and instead emulate it with an intercrate check)
 - #121829 (Dummy tweaks (attempt 2))
 - #121857 (Implement async closure signature deduction)
 - #121894 (const_eval_select: make it safe but be careful with what we expose on stable for now)
 - #122014 (Change some attributes to only_local.)
 - #122016 (will_wake tests fail on Miri and that is expected)
 - #122018 (only set noalias on Box with the global allocator)
 - #122028 (Remove some dead code)

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

Author: bors

compiler/rustc_abi/src/lib.rs

@@ -1612,8 +1612,9 @@ pub enum PointerKind {
     SharedRef { frozen: bool },
     /// Mutable reference. `unpin` indicates the absence of any pinned data.
     MutableRef { unpin: bool },
-    /// Box. `unpin` indicates the absence of any pinned data.
-    Box { unpin: bool },
+    /// Box. `unpin` indicates the absence of any pinned data. `global` indicates whether this box
+    /// uses the global allocator or a custom one.
+    Box { unpin: bool, global: bool },
 }
 
 /// Note that this information is advisory only, and backends are free to ignore it.
@@ -1622,6 +1623,8 @@ pub enum PointerKind {
 pub struct PointeeInfo {
     pub size: Size,
     pub align: Align,
+    /// If this is `None`, then this is a raw pointer, so size and alignment are not guaranteed to
+    /// be reliable.
     pub safe: Option<PointerKind>,
 }
 

compiler/rustc_ast/src/mut_visit.rs

@@ -1604,7 +1604,10 @@ pub fn noop_visit_capture_by<T: MutVisitor>(capture_by: &mut CaptureBy, vis: &mu
     }
 }
 
-/// Some value for the AST node that is valid but possibly meaningless.
+/// Some value for the AST node that is valid but possibly meaningless. Similar
+/// to `Default` but not intended for wide use. The value will never be used
+/// meaningfully, it exists just to support unwinding in `visit_clobber` in the
+/// case where its closure panics.
 pub trait DummyAstNode {
     fn dummy() -> Self;
 }
@@ -1679,19 +1682,6 @@ impl DummyAstNode for Stmt {
     }
 }
 
-impl DummyAstNode for Block {
-    fn dummy() -> Self {
-        Block {
-            stmts: Default::default(),
-            id: DUMMY_NODE_ID,
-            rules: BlockCheckMode::Default,
-            span: Default::default(),
-            tokens: Default::default(),
-            could_be_bare_literal: Default::default(),
-        }
-    }
-}
-
 impl DummyAstNode for Crate {
     fn dummy() -> Self {
         Crate {