Auto merge of #92587 - matthiaskrgr:rollup-qnwa8qx, r=matthiaskrgr

Rollup of 7 pull requests

Successful merges:

 - #92092 (Drop guards in slice sorting derive src pointers from &mut T, which is invalidated by interior mutation in comparison)
 - #92388 (Fix a minor mistake in `String::try_reserve_exact` examples)
 - #92442 (Add negative `impl` for `Ord`, `PartialOrd` on `LocalDefId`)
 - #92483 (Stabilize `result_cloned` and `result_copied`)
 - #92574 (Add RISC-V detection macro and more architecture instructions)
 - #92575 (ast: Always keep a `NodeId` in `ast::Crate`)
 - #92583 (:arrow_up: rust-analyzer)

Failed merges:

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

compiler/rustc_ast/src/ast.rs

@@ -510,8 +510,10 @@ pub struct Crate {
     pub attrs: Vec<Attribute>,
     pub items: Vec<P<Item>>,
     pub span: Span,
-    // Placeholder ID if the crate node is a macro placeholder.
-    pub is_placeholder: Option<NodeId>,
+    /// Must be equal to `CRATE_NODE_ID` after the crate root is expanded, but may hold
+    /// expansion placeholders or an unassigned value (`DUMMY_NODE_ID`) before that.
+    pub id: NodeId,
+    pub is_placeholder: bool,
 }
 
 /// Possible values inside of compile-time attribute lists.

compiler/rustc_ast/src/mut_visit.rs

@@ -1109,7 +1109,8 @@ pub fn noop_visit_fn_header<T: MutVisitor>(header: &mut FnHeader, vis: &mut T) {
 }
 
 pub fn noop_visit_crate<T: MutVisitor>(krate: &mut Crate, vis: &mut T) {
-    let Crate { attrs, items, span, is_placeholder: _ } = krate;
+    let Crate { attrs, items, span, id, is_placeholder: _ } = krate;
+    vis.visit_id(id);
     visit_attrs(attrs, vis);
     items.flat_map_in_place(|item| vis.flat_map_item(item));
     vis.visit_span(span);
@@ -1554,6 +1555,7 @@ impl DummyAstNode for Crate {
             attrs: Default::default(),
             items: Default::default(),
             span: Default::default(),
+            id: DUMMY_NODE_ID,
             is_placeholder: Default::default(),
         }
     }

compiler/rustc_expand/src/expand.rs

@@ -377,6 +377,7 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
             dir_path,
         });
         let krate = self.fully_expand_fragment(AstFragment::Crate(krate)).make_crate();
+        assert_eq!(krate.id, ast::CRATE_NODE_ID);
         self.cx.trace_macros_diag();
         krate
     }
@@ -1169,7 +1170,8 @@ impl<'a, 'b> MutVisitor for InvocationCollector<'a, 'b> {
                         attrs: Vec::new(),
                         items: Vec::new(),
                         span,
-                        is_placeholder: None,
+                        id: self.cx.resolver.next_node_id(),
+                        is_placeholder: false,
                     };
                 }
             };
@@ -1180,7 +1182,7 @@ impl<'a, 'b> MutVisitor for InvocationCollector<'a, 'b> {
                     .make_crate();
             }
 
-            noop_visit_crate(&mut krate, self);
+            assign_id!(self, &mut krate.id, || noop_visit_crate(&mut krate, self));
             krate
         })
     }

compiler/rustc_expand/src/placeholders.rs

@@ -50,7 +50,8 @@ pub fn placeholder(
             attrs: Default::default(),
             items: Default::default(),
             span,
-            is_placeholder: Some(id),
+            id,
+            is_placeholder: true,
         }),
         AstFragmentKind::Expr => AstFragment::Expr(expr_placeholder()),
         AstFragmentKind::OptExpr => AstFragment::OptExpr(Some(expr_placeholder())),
@@ -362,8 +363,8 @@ impl MutVisitor for PlaceholderExpander {
     }
 
     fn visit_crate(&mut self, krate: &mut ast::Crate) {
-        if let Some(id) = krate.is_placeholder {
-            *krate = self.remove(id).make_crate();
+        if krate.is_placeholder {
+            *krate = self.remove(krate.id).make_crate();
         } else {
             noop_visit_crate(krate, self)
         }

compiler/rustc_interface/src/passes.rs

@@ -3,7 +3,7 @@ use crate::proc_macro_decls;
 use crate::util;
 
 use rustc_ast::mut_visit::MutVisitor;
-use rustc_ast::{self as ast, visit};
+use rustc_ast::{self as ast, visit, DUMMY_NODE_ID};
 use rustc_borrowck as mir_borrowck;
 use rustc_codegen_ssa::back::link::emit_metadata;
 use rustc_codegen_ssa::traits::CodegenBackend;
@@ -323,7 +323,7 @@ pub fn configure_and_expand(
 
         let crate_attrs = krate.attrs.clone();
         let extern_mod_loaded = |ident: Ident, attrs, items, span| {
-            let krate = ast::Crate { attrs, items, span, is_placeholder: None };
+            let krate = ast::Crate { attrs, items, span, id: DUMMY_NODE_ID, is_placeholder: false };
             pre_expansion_lint(sess, lint_store, &krate, &crate_attrs, ident.name.as_str());
             (krate.attrs, krate.items)
         };

compiler/rustc_parse/src/parser/item.rs

@@ -27,7 +27,7 @@ impl<'a> Parser<'a> {
     /// Parses a source module as a crate. This is the main entry point for the parser.
     pub fn parse_crate_mod(&mut self) -> PResult<'a, ast::Crate> {
         let (attrs, items, span) = self.parse_mod(&token::Eof)?;
-        Ok(ast::Crate { attrs, items, span, is_placeholder: None })
+        Ok(ast::Crate { attrs, items, span, id: DUMMY_NODE_ID, is_placeholder: false })
     }
 
     /// Parses a `mod <foo> { ... }` or `mod <foo>;` item.

compiler/rustc_resolve/src/build_reduced_graph.rs

@@ -1512,8 +1512,8 @@ impl<'a, 'b> Visitor<'b> for BuildReducedGraphVisitor<'a, 'b> {
     }
 
     fn visit_crate(&mut self, krate: &'b ast::Crate) {
-        if let Some(id) = krate.is_placeholder {
-            self.visit_invoc_in_module(id);
+        if krate.is_placeholder {
+            self.visit_invoc_in_module(krate.id);
         } else {
             visit::walk_crate(self, krate);
             self.contains_macro_use(&krate.attrs);

compiler/rustc_resolve/src/def_collector.rs

@@ -344,8 +344,8 @@ impl<'a, 'b> visit::Visitor<'a> for DefCollector<'a, 'b> {
     }
 
     fn visit_crate(&mut self, krate: &'a Crate) {
-        if let Some(id) = krate.is_placeholder {
-            self.visit_macro_invoc(id)
+        if krate.is_placeholder {
+            self.visit_macro_invoc(krate.id)
         } else {
             visit::walk_crate(self, krate)
         }

compiler/rustc_resolve/src/lib.rs

@@ -68,7 +68,7 @@ use smallvec::{smallvec, SmallVec};
 use std::cell::{Cell, RefCell};
 use std::collections::{BTreeMap, BTreeSet};
 use std::ops::ControlFlow;
-use std::{cmp, fmt, iter, ptr};
+use std::{cmp, fmt, iter, mem, ptr};
 use tracing::debug;
 
 use diagnostics::{extend_span_to_previous_binding, find_span_of_binding_until_next_binding};
@@ -1394,7 +1394,7 @@ impl<'a> Resolver<'a> {
                 .chain(features.declared_lang_features.iter().map(|(feat, ..)| *feat))
                 .collect(),
             lint_buffer: LintBuffer::default(),
-            next_node_id: NodeId::from_u32(1),
+            next_node_id: CRATE_NODE_ID,
             node_id_to_def_id,
             def_id_to_node_id,
             placeholder_field_indices: Default::default(),
@@ -1430,8 +1430,7 @@ impl<'a> Resolver<'a> {
     pub fn next_node_id(&mut self) -> NodeId {
         let next =
             self.next_node_id.as_u32().checked_add(1).expect("input too large; ran out of NodeIds");
-        self.next_node_id = ast::NodeId::from_u32(next);
-        self.next_node_id
+        mem::replace(&mut self.next_node_id, ast::NodeId::from_u32(next))
     }
 
     pub fn lint_buffer(&mut self) -> &mut LintBuffer {

compiler/rustc_span/src/def_id.rs

@@ -316,17 +316,23 @@ impl fmt::Debug for DefId {
 
 rustc_data_structures::define_id_collections!(DefIdMap, DefIdSet, DefId);
 
-/// A LocalDefId is equivalent to a DefId with `krate == LOCAL_CRATE`. Since
+/// A `LocalDefId` is equivalent to a `DefId` with `krate == LOCAL_CRATE`. Since
 /// we encode this information in the type, we can ensure at compile time that
-/// no DefIds from upstream crates get thrown into the mix. There are quite a
-/// few cases where we know that only DefIds from the local crate are expected
-/// and a DefId from a different crate would signify a bug somewhere. This
-/// is when LocalDefId comes in handy.
+/// no `DefId`s from upstream crates get thrown into the mix. There are quite a
+/// few cases where we know that only `DefId`s from the local crate are expected;
+/// a `DefId` from a different crate would signify a bug somewhere. This
+/// is when `LocalDefId` comes in handy.
 #[derive(Clone, Copy, PartialEq, Eq, Hash)]
 pub struct LocalDefId {
     pub local_def_index: DefIndex,
 }
 
+// To ensure correctness of incremental compilation,
+// `LocalDefId` must not implement `Ord` or `PartialOrd`.
+// See https://github.com/rust-lang/rust/issues/90317.
+impl !Ord for LocalDefId {}
+impl !PartialOrd for LocalDefId {}
+
 pub const CRATE_DEF_ID: LocalDefId = LocalDefId { local_def_index: CRATE_DEF_INDEX };
 
 impl Idx for LocalDefId {

library/alloc/src/slice.rs

@@ -892,7 +892,7 @@ where
             //    performance than with the 2nd method.
             //
             // All methods were benchmarked, and the 3rd showed best results. So we chose that one.
-            let mut tmp = mem::ManuallyDrop::new(ptr::read(&v[0]));
+            let tmp = mem::ManuallyDrop::new(ptr::read(&v[0]));
 
             // Intermediate state of the insertion process is always tracked by `hole`, which
             // serves two purposes:
@@ -904,7 +904,7 @@ where
             // If `is_less` panics at any point during the process, `hole` will get dropped and
             // fill the hole in `v` with `tmp`, thus ensuring that `v` still holds every object it
             // initially held exactly once.
-            let mut hole = InsertionHole { src: &mut *tmp, dest: &mut v[1] };
+            let mut hole = InsertionHole { src: &*tmp, dest: &mut v[1] };
             ptr::copy_nonoverlapping(&v[1], &mut v[0], 1);
 
             for i in 2..v.len() {
@@ -920,7 +920,7 @@ where
 
     // When dropped, copies from `src` into `dest`.
     struct InsertionHole<T> {
-        src: *mut T,
+        src: *const T,
         dest: *mut T,
     }
 

library/alloc/src/string.rs

@@ -1062,7 +1062,7 @@ impl String {
     ///     let mut output = String::new();
     ///
     ///     // Pre-reserve the memory, exiting if we can't
-    ///     output.try_reserve(data.len())?;
+    ///     output.try_reserve_exact(data.len())?;
     ///
     ///     // Now we know this can't OOM in the middle of our complex work
     ///     output.push_str(data);

library/core/src/hint.rs

@@ -123,6 +123,21 @@ pub fn spin_loop() {
         }
     }
 
+    // RISC-V platform spin loop hint implementation
+    {
+        // RISC-V RV32 and RV64 share the same PAUSE instruction, but they are located in different
+        // modules in `core::arch`.
+        // In this case, here we call `pause` function in each core arch module.
+        #[cfg(target_arch = "riscv32")]
+        {
+            crate::arch::riscv32::pause();
+        }
+        #[cfg(target_arch = "riscv64")]
+        {
+            crate::arch::riscv64::pause();
+        }
+    }
+
     #[cfg(any(target_arch = "aarch64", all(target_arch = "arm", target_feature = "v6")))]
     {
         #[cfg(target_arch = "aarch64")]
@@ -137,11 +152,6 @@ pub fn spin_loop() {
             unsafe { crate::arch::arm::__yield() };
         }
     }
-
-    #[cfg(any(target_arch = "riscv32", target_arch = "riscv64"))]
-    {
-        crate::arch::riscv::pause();
-    }
 }
 
 /// An identity function that *__hints__* to the compiler to be maximally pessimistic about what

library/core/src/result.rs

@@ -1504,14 +1504,14 @@ impl<T, E> Result<&T, E> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(result_copied)]
     /// let val = 12;
     /// let x: Result<&i32, i32> = Ok(&val);
     /// assert_eq!(x, Ok(&12));
     /// let copied = x.copied();
     /// assert_eq!(copied, Ok(12));
     /// ```
-    #[unstable(feature = "result_copied", reason = "newly added", issue = "63168")]
+    #[inline]
+    #[stable(feature = "result_copied", since = "1.59.0")]
     pub fn copied(self) -> Result<T, E>
     where
         T: Copy,
@@ -1525,14 +1525,14 @@ impl<T, E> Result<&T, E> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(result_cloned)]
     /// let val = 12;
     /// let x: Result<&i32, i32> = Ok(&val);
     /// assert_eq!(x, Ok(&12));
     /// let cloned = x.cloned();
     /// assert_eq!(cloned, Ok(12));
     /// ```
-    #[unstable(feature = "result_cloned", reason = "newly added", issue = "63168")]
+    #[inline]
+    #[stable(feature = "result_cloned", since = "1.59.0")]
     pub fn cloned(self) -> Result<T, E>
     where
         T: Clone,
@@ -1548,14 +1548,14 @@ impl<T, E> Result<&mut T, E> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(result_copied)]
     /// let mut val = 12;
     /// let x: Result<&mut i32, i32> = Ok(&mut val);
     /// assert_eq!(x, Ok(&mut 12));
     /// let copied = x.copied();
     /// assert_eq!(copied, Ok(12));
     /// ```
-    #[unstable(feature = "result_copied", reason = "newly added", issue = "63168")]
+    #[inline]
+    #[stable(feature = "result_copied", since = "1.59.0")]
     pub fn copied(self) -> Result<T, E>
     where
         T: Copy,
@@ -1569,14 +1569,14 @@ impl<T, E> Result<&mut T, E> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(result_cloned)]
     /// let mut val = 12;
     /// let x: Result<&mut i32, i32> = Ok(&mut val);
     /// assert_eq!(x, Ok(&mut 12));
     /// let cloned = x.cloned();
     /// assert_eq!(cloned, Ok(12));
     /// ```
-    #[unstable(feature = "result_cloned", reason = "newly added", issue = "63168")]
+    #[inline]
+    #[stable(feature = "result_cloned", since = "1.59.0")]
     pub fn cloned(self) -> Result<T, E>
     where
         T: Clone,

library/core/src/slice/sort.rs

@@ -12,7 +12,7 @@ use crate::ptr;
 
 /// When dropped, copies from `src` into `dest`.
 struct CopyOnDrop<T> {
-    src: *mut T,
+    src: *const T,
     dest: *mut T,
 }
 
@@ -54,9 +54,9 @@ where
             // Read the first element into a stack-allocated variable. If a following comparison
             // operation panics, `hole` will get dropped and automatically write the element back
             // into the slice.
-            let mut tmp = mem::ManuallyDrop::new(ptr::read(v.get_unchecked(0)));
+            let tmp = mem::ManuallyDrop::new(ptr::read(v.get_unchecked(0)));
             let v = v.as_mut_ptr();
-            let mut hole = CopyOnDrop { src: &mut *tmp, dest: v.add(1) };
+            let mut hole = CopyOnDrop { src: &*tmp, dest: v.add(1) };
             ptr::copy_nonoverlapping(v.add(1), v.add(0), 1);
 
             for i in 2..len {
@@ -100,9 +100,9 @@ where
             // Read the last element into a stack-allocated variable. If a following comparison
             // operation panics, `hole` will get dropped and automatically write the element back
             // into the slice.
-            let mut tmp = mem::ManuallyDrop::new(ptr::read(v.get_unchecked(len - 1)));
+            let tmp = mem::ManuallyDrop::new(ptr::read(v.get_unchecked(len - 1)));
             let v = v.as_mut_ptr();
-            let mut hole = CopyOnDrop { src: &mut *tmp, dest: v.add(len - 2) };
+            let mut hole = CopyOnDrop { src: &*tmp, dest: v.add(len - 2) };
             ptr::copy_nonoverlapping(v.add(len - 2), v.add(len - 1), 1);
 
             for i in (0..len - 2).rev() {
@@ -498,8 +498,8 @@ where
         // operation panics, the pivot will be automatically written back into the slice.
 
         // SAFETY: `pivot` is a reference to the first element of `v`, so `ptr::read` is safe.
-        let mut tmp = mem::ManuallyDrop::new(unsafe { ptr::read(pivot) });
-        let _pivot_guard = CopyOnDrop { src: &mut *tmp, dest: pivot };
+        let tmp = mem::ManuallyDrop::new(unsafe { ptr::read(pivot) });
+        let _pivot_guard = CopyOnDrop { src: &*tmp, dest: pivot };
         let pivot = &*tmp;
 
         // Find the first pair of out-of-order elements.
@@ -551,8 +551,8 @@ where
     // Read the pivot into a stack-allocated variable for efficiency. If a following comparison
     // operation panics, the pivot will be automatically written back into the slice.
     // SAFETY: The pointer here is valid because it is obtained from a reference to a slice.
-    let mut tmp = mem::ManuallyDrop::new(unsafe { ptr::read(pivot) });
-    let _pivot_guard = CopyOnDrop { src: &mut *tmp, dest: pivot };
+    let tmp = mem::ManuallyDrop::new(unsafe { ptr::read(pivot) });
+    let _pivot_guard = CopyOnDrop { src: &*tmp, dest: pivot };
     let pivot = &*tmp;
 
     // Now partition the slice.

library/std/src/lib.rs

@@ -556,6 +556,7 @@ pub use std_detect::*;
 pub use std_detect::{
     is_aarch64_feature_detected, is_arm_feature_detected, is_mips64_feature_detected,
     is_mips_feature_detected, is_powerpc64_feature_detected, is_powerpc_feature_detected,
+    is_riscv_feature_detected,
 };
 
 // Re-export macros defined in libcore.

src/test/ui/ast-json/ast-json-noexpand-output.stdout

@@ -1 +1 @@
-{"attrs":[{"kind":{"variant":"Normal","fields":[{"path":{"span":{"lo":0,"hi":0},"segments":[{"ident":{"name":"crate_type","span":{"lo":0,"hi":0}},"id":0,"args":null}],"tokens":null},"args":{"variant":"Eq","fields":[{"lo":0,"hi":0},{"kind":{"variant":"Interpolated","fields":[{"variant":"NtExpr","fields":[{"id":0,"kind":{"variant":"Lit","fields":[{"token":{"kind":"Str","symbol":"lib","suffix":null},"kind":{"variant":"Str","fields":["lib","Cooked"]},"span":{"lo":0,"hi":0}}]},"span":{"lo":0,"hi":0},"attrs":{"0":null},"tokens":{"0":[[{"variant":"Token","fields":[{"kind":{"variant":"Literal","fields":[{"kind":"Str","symbol":"lib","suffix":null}]},"span":{"lo":0,"hi":0}}]},"Alone"]]}}]}]},"span":{"lo":0,"hi":0}}]},"tokens":null},{"0":[[{"variant":"Token","fields":[{"kind":"Pound","span":{"lo":0,"hi":0}}]},"Joint"],[{"variant":"Token","fields":[{"kind":"Not","span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Delimited","fields":[{"open":{"lo":0,"hi":0},"close":{"lo":0,"hi":0}},"Bracket",{"0":[[{"variant":"Token","fields":[{"kind":{"variant":"Ident","fields":["crate_type",false]},"span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Token","fields":[{"kind":"Eq","span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Token","fields":[{"kind":{"variant":"Literal","fields":[{"kind":"Str","symbol":"lib","suffix":null}]},"span":{"lo":0,"hi":0}}]},"Alone"]]}]},"Alone"]]}]},"id":null,"style":"Inner","span":{"lo":0,"hi":0}}],"items":[{"attrs":[],"id":0,"span":{"lo":0,"hi":0},"vis":{"kind":"Inherited","span":{"lo":0,"hi":0},"tokens":null},"ident":{"name":"core","span":{"lo":0,"hi":0}},"kind":{"variant":"ExternCrate","fields":[null]},"tokens":null}],"span":{"lo":0,"hi":0},"is_placeholder":null}
+{"attrs":[{"kind":{"variant":"Normal","fields":[{"path":{"span":{"lo":0,"hi":0},"segments":[{"ident":{"name":"crate_type","span":{"lo":0,"hi":0}},"id":0,"args":null}],"tokens":null},"args":{"variant":"Eq","fields":[{"lo":0,"hi":0},{"kind":{"variant":"Interpolated","fields":[{"variant":"NtExpr","fields":[{"id":0,"kind":{"variant":"Lit","fields":[{"token":{"kind":"Str","symbol":"lib","suffix":null},"kind":{"variant":"Str","fields":["lib","Cooked"]},"span":{"lo":0,"hi":0}}]},"span":{"lo":0,"hi":0},"attrs":{"0":null},"tokens":{"0":[[{"variant":"Token","fields":[{"kind":{"variant":"Literal","fields":[{"kind":"Str","symbol":"lib","suffix":null}]},"span":{"lo":0,"hi":0}}]},"Alone"]]}}]}]},"span":{"lo":0,"hi":0}}]},"tokens":null},{"0":[[{"variant":"Token","fields":[{"kind":"Pound","span":{"lo":0,"hi":0}}]},"Joint"],[{"variant":"Token","fields":[{"kind":"Not","span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Delimited","fields":[{"open":{"lo":0,"hi":0},"close":{"lo":0,"hi":0}},"Bracket",{"0":[[{"variant":"Token","fields":[{"kind":{"variant":"Ident","fields":["crate_type",false]},"span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Token","fields":[{"kind":"Eq","span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Token","fields":[{"kind":{"variant":"Literal","fields":[{"kind":"Str","symbol":"lib","suffix":null}]},"span":{"lo":0,"hi":0}}]},"Alone"]]}]},"Alone"]]}]},"id":null,"style":"Inner","span":{"lo":0,"hi":0}}],"items":[{"attrs":[],"id":0,"span":{"lo":0,"hi":0},"vis":{"kind":"Inherited","span":{"lo":0,"hi":0},"tokens":null},"ident":{"name":"core","span":{"lo":0,"hi":0}},"kind":{"variant":"ExternCrate","fields":[null]},"tokens":null}],"span":{"lo":0,"hi":0},"id":0,"is_placeholder":false}