Rollup of 22 pull requests

compiler/rustc_ast/src/ast.rs

@@ -3915,7 +3915,7 @@ pub struct EiiImpl {
     ///
     /// This field is that shortcut: we prefill the extern target to skip a name resolution step,
     /// making sure it never fails. It'd be awful UX if we fail name resolution in code invisible to the user.
-    pub known_eii_macro_resolution: Option<EiiDecl>,
+    pub known_eii_macro_resolution: Option<Path>,
     pub impl_safety: Safety,
     pub span: Span,
     pub inner_span: Span,

compiler/rustc_ast/src/ast_traits.rs

@@ -62,7 +62,7 @@ impl<T: HasNodeId> HasNodeId for Box<T> {
 }
 
 /// A trait for AST nodes having (or not having) collected tokens.
-pub trait HasTokens {
+pub trait HasTokens: HasAttrs {
     fn tokens(&self) -> Option<&LazyAttrTokenStream>;
     fn tokens_mut(&mut self) -> Option<&mut Option<LazyAttrTokenStream>>;
 }
@@ -109,7 +109,7 @@ impl_has_tokens_none!(
     WherePredicate
 );
 
-impl<T> HasTokens for WithTokens<T> {
+impl<T: HasAttrs> HasTokens for WithTokens<T> {
     fn tokens(&self) -> Option<&LazyAttrTokenStream> {
         self.tokens.as_ref()
     }

compiler/rustc_ast/src/attr/mod.rs

@@ -7,7 +7,7 @@ use std::fmt::Debug;
 use std::sync::atomic::{AtomicU32, Ordering};
 
 use rustc_index::bit_set::GrowableBitSet;
-use rustc_span::{Ident, Span, Symbol, sym};
+use rustc_span::{Ident, Span, Symbol, kw, sym};
 use smallvec::{SmallVec, smallvec};
 use thin_vec::{ThinVec, thin_vec};
 
@@ -21,7 +21,8 @@ use crate::token::{
     self, CommentKind, Delimiter, DocFragmentKind, InvisibleOrigin, MetaVarKind, Token,
 };
 use crate::tokenstream::{
-    DelimSpan, LazyAttrTokenStream, Spacing, TokenStream, TokenStreamIter, TokenTree,
+    AttrTokenStream, AttrTokenTree, DelimSpacing, DelimSpan, LazyAttrTokenStream, Spacing,
+    TokenStream, TokenStreamIter, TokenTree,
 };
 use crate::util::comments;
 use crate::util::literal::escape_string_symbol;
@@ -737,23 +738,6 @@ pub fn mk_doc_comment(
     Attribute { kind: AttrKind::DocComment(comment_kind, data), id: g.mk_attr_id(), style, span }
 }
 
-fn mk_attr(
-    g: &AttrIdGenerator,
-    style: AttrStyle,
-    unsafety: Safety,
-    path: Path,
-    args: AttrArgs,
-    span: Span,
-) -> Attribute {
-    mk_attr_from_item(
-        g,
-        AttrItem { unsafety, path, args: AttrItemKind::Unparsed(args) },
-        None,
-        style,
-        span,
-    )
-}
-
 pub fn mk_attr_from_item(
     g: &AttrIdGenerator,
     item: AttrItem,
@@ -769,6 +753,50 @@ pub fn mk_attr_from_item(
     }
 }
 
+fn mk_attr_tokens(
+    style: AttrStyle,
+    unsafety: Safety,
+    item_tokens: AttrTokenStream,
+    span: Span,
+) -> LazyAttrTokenStream {
+    let safety_kw = match unsafety {
+        Safety::Default => None,
+        Safety::Unsafe(span) => Some((kw::Unsafe, span)),
+        Safety::Safe(span) => Some((kw::Safe, span)),
+    };
+    let item_tokens = if let Some((kw, kw_span)) = safety_kw {
+        AttrTokenStream::new(vec![
+            AttrTokenTree::Token(Token::from_ast_ident(Ident::new(kw, kw_span)), Spacing::Alone),
+            AttrTokenTree::Delimited(
+                DelimSpan::from_single(span),
+                DelimSpacing::new(Spacing::JointHidden, Spacing::Alone),
+                Delimiter::Parenthesis,
+                item_tokens,
+            ),
+        ])
+    } else {
+        item_tokens
+    };
+
+    let mut tokens = match style {
+        AttrStyle::Outer => {
+            vec![AttrTokenTree::Token(Token::new(token::Pound, span), Spacing::JointHidden)]
+        }
+        AttrStyle::Inner => vec![
+            AttrTokenTree::Token(Token::new(token::Pound, span), Spacing::Joint),
+            AttrTokenTree::Token(Token::new(token::Bang, span), Spacing::JointHidden),
+        ],
+    };
+    tokens.push(AttrTokenTree::Delimited(
+        DelimSpan::from_single(span),
+        DelimSpacing::new(Spacing::JointHidden, Spacing::Alone),
+        Delimiter::Bracket,
+        item_tokens,
+    ));
+
+    LazyAttrTokenStream::new_direct(AttrTokenStream::new(tokens))
+}
+
 pub fn mk_attr_word(
     g: &AttrIdGenerator,
     style: AttrStyle,
@@ -778,7 +806,24 @@ pub fn mk_attr_word(
 ) -> Attribute {
     let path = Path::from_ident(Ident::new(name, span));
     let args = AttrArgs::Empty;
-    mk_attr(g, style, unsafety, path, args, span)
+
+    let tokens = Some(mk_attr_tokens(
+        style,
+        unsafety,
+        AttrTokenStream::new(vec![AttrTokenTree::Token(
+            Token::from_ast_ident(Ident::new(name, span)),
+            Spacing::Alone,
+        )]),
+        span,
+    ));
+
+    mk_attr_from_item(
+        g,
+        AttrItem { unsafety, path, args: AttrItemKind::Unparsed(args) },
+        tokens,
+        style,
+        span,
+    )
 }
 
 pub fn mk_attr_nested_word(
@@ -800,7 +845,32 @@ pub fn mk_attr_nested_word(
         delim: Delimiter::Parenthesis,
         tokens: inner_tokens,
     });
-    mk_attr(g, style, unsafety, path, attr_args, span)
+
+    let tokens = Some(mk_attr_tokens(
+        style,
+        unsafety,
+        AttrTokenStream::new(vec![
+            AttrTokenTree::Token(Token::from_ast_ident(Ident::new(outer, span)), Spacing::Alone),
+            AttrTokenTree::Delimited(
+                DelimSpan::from_single(span),
+                DelimSpacing::new(Spacing::JointHidden, Spacing::Alone),
+                Delimiter::Parenthesis,
+                AttrTokenStream::new(vec![AttrTokenTree::Token(
+                    Token::from_ast_ident(Ident::new(inner, span)),
+                    Spacing::Alone,
+                )]),
+            ),
+        ]),
+        span,
+    ));
+
+    mk_attr_from_item(
+        g,
+        AttrItem { unsafety, path, args: AttrItemKind::Unparsed(attr_args) },
+        tokens,
+        style,
+        span,
+    )
 }
 
 pub fn mk_attr_name_value_str(
@@ -821,7 +891,28 @@ pub fn mk_attr_name_value_str(
     });
     let path = Path::from_ident(Ident::new(name, span));
     let args = AttrArgs::Eq { eq_span: span, expr };
-    mk_attr(g, style, unsafety, path, args, span)
+
+    let tokens = Some(mk_attr_tokens(
+        style,
+        unsafety,
+        AttrTokenStream::new(vec![
+            AttrTokenTree::Token(Token::from_ast_ident(Ident::new(name, span)), Spacing::Alone),
+            AttrTokenTree::Token(Token::new(token::Eq, span), Spacing::Alone),
+            AttrTokenTree::Token(
+                Token::new(token::TokenKind::lit(lit.kind, lit.symbol, lit.suffix), span),
+                Spacing::Alone,
+            ),
+        ]),
+        span,
+    ));
+
+    mk_attr_from_item(
+        g,
+        AttrItem { unsafety, path, args: AttrItemKind::Unparsed(args) },
+        tokens,
+        style,
+        span,
+    )
 }
 
 pub fn filter_by_name(attrs: &[Attribute], name: Symbol) -> impl Iterator<Item = &Attribute> {

compiler/rustc_ast/src/tokenstream.rs

@@ -18,7 +18,7 @@ use rustc_span::{DUMMY_SP, Span, SpanDecoder, SpanEncoder, Symbol, sym};
 use thin_vec::ThinVec;
 
 use crate::ast::AttrStyle;
-use crate::ast_traits::{HasAttrs, HasTokens};
+use crate::ast_traits::HasTokens;
 use crate::token::{self, Delimiter, Token, TokenKind};
 use crate::{AttrVec, Attribute};
 
@@ -653,7 +653,7 @@ impl TokenStream {
         TokenStream::new(vec![TokenTree::token_alone(kind, span)])
     }
 
-    pub fn from_ast(node: &(impl HasAttrs + HasTokens + fmt::Debug)) -> TokenStream {
+    pub fn from_ast(node: &(impl HasTokens + fmt::Debug)) -> TokenStream {
         let tokens = node.tokens().unwrap_or_else(|| panic!("missing tokens for node: {:?}", node));
         let mut tts = vec![];
         attrs_and_tokens_to_token_trees(node.attrs(), tokens, &mut tts);

compiler/rustc_ast_lowering/src/expr/closure.rs

@@ -38,6 +38,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     &closure.body,
                     closure.fn_decl_span,
                     closure.fn_arg_span,
+                    attrs,
                 ),
                 span: self.lower_span(e.span),
             },
@@ -240,7 +241,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
             fn_decl_span: self.lower_span(fn_decl_span),
             fn_arg_span: Some(self.lower_span(fn_arg_span)),
             kind: closure_kind,
-            constness: self.lower_constness(constness),
+            constness: self.lower_constness(attrs, constness),
             explicit_captures,
         });
 
@@ -308,6 +309,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         body: &Expr,
         fn_decl_span: Span,
         fn_arg_span: Span,
+        attrs: &[hir::Attribute],
     ) -> hir::ExprKind<'hir> {
         let closure_def_id = self.local_def_id(closure_id);
         let (binder_clause, generic_params) = self.lower_closure_binder(binder);
@@ -369,7 +371,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
             // knows that a `FnDecl` output type like `-> &str` actually means
             // "coroutine that returns &str", rather than directly returning a `&str`.
             kind: hir::ClosureKind::CoroutineClosure(coroutine_desugaring),
-            constness: self.lower_constness(constness),
+            constness: self.lower_constness(attrs, constness),
             explicit_captures: &[],
         });
         hir::ExprKind::Closure(c)

compiler/rustc_ast_lowering/src/item.rs

@@ -141,13 +141,9 @@ impl<'hir> LoweringContext<'_, 'hir> {
         }: &EiiImpl,
     ) -> hir::attrs::EiiImpl {
         let resolution = if let Some(target) = known_eii_macro_resolution
-            && let Some(decl) = self.lower_eii_decl(
-                *node_id,
-                // the expect is ok here since we always generate this path in the eii macro.
-                eii_macro_path.segments.last().expect("at least one segment").ident,
-                target,
-            ) {
-            EiiImplResolution::Known(decl)
+            && let Some(foreign_item_did) = self.lower_path_simple_eii(*node_id, target)
+        {
+            EiiImplResolution::Known(foreign_item_did)
         } else if let Some(macro_did) = self.lower_path_simple_eii(*node_id, eii_macro_path) {
             EiiImplResolution::Macro(macro_did)
         } else {
@@ -479,7 +475,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     .arena
                     .alloc_from_iter(impl_items.iter().map(|item| self.lower_impl_item_ref(item)));
 
-                let constness = self.lower_constness(*constness);
+                let constness = self.lower_constness(attrs, *constness);
 
                 hir::ItemKind::Impl(hir::Impl {
                     generics,
@@ -499,7 +495,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 bounds,
                 items,
             }) => {
-                let constness = self.lower_constness(*constness);
+                let constness = self.lower_constness(attrs, *constness);
                 let impl_restriction = self.lower_impl_restriction(impl_restriction);
                 let ident = self.lower_ident(*ident);
                 let (generics, (safety, items, bounds)) = self.lower_generics(
@@ -530,7 +526,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 }
             }
             ItemKind::TraitAlias(TraitAlias { constness, ident, generics, bounds }) => {
-                let constness = self.lower_constness(*constness);
+                let constness = self.lower_constness(attrs, *constness);
                 let ident = self.lower_ident(*ident);
                 let (generics, bounds) = self.lower_generics(
                     generics,
@@ -1702,21 +1698,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
             safety.into()
         };
 
-        let mut constness = self.lower_constness(h.constness);
-        if let Some(&attr_span) = find_attr!(attrs, RustcComptime(span) => span) {
-            match std::mem::replace(&mut constness, rustc_hir::Constness::Const { always: true }) {
-                rustc_hir::Constness::Const { always: true } => {
-                    unreachable!("lower_constness cannot produce comptime")
-                }
-                // A function can't be `const` and `comptime` at the same time
-                rustc_hir::Constness::Const { always: false } => {
-                    let Const::Yes(span) = h.constness else { unreachable!() };
-                    self.dcx().emit_err(ConstComptimeFn { span, attr_span });
-                }
-                // Good
-                rustc_hir::Constness::NotConst => {}
-            }
-        }
+        let constness = self.lower_constness(attrs, h.constness);
 
         hir::FnHeader { safety, asyncness, constness, abi: self.lower_extern(h.ext) }
     }
@@ -1778,11 +1760,30 @@ impl<'hir> LoweringContext<'_, 'hir> {
         });
     }
 
-    pub(super) fn lower_constness(&mut self, c: Const) -> hir::Constness {
-        match c {
+    /// Lowers constness or comptime attribute.
+    /// Whether `const` is allowed here is checked by ast validation.
+    /// Whether `comptime` is allowed here is checked by the `comptime` attribute parser.
+    pub(super) fn lower_constness(&mut self, attrs: &[hir::Attribute], c: Const) -> hir::Constness {
+        let mut constness = match c {
             Const::Yes(_) => hir::Constness::Const { always: false },
             Const::No => hir::Constness::NotConst,
+        };
+
+        if let Some(&attr_span) = find_attr!(attrs, RustcComptime(span) => span) {
+            match std::mem::replace(&mut constness, hir::Constness::Const { always: true }) {
+                hir::Constness::Const { always: true } => {
+                    unreachable!("lower_constness cannot produce comptime")
+                }
+                // A function can't be `const` and `comptime` at the same time
+                hir::Constness::Const { always: false } => {
+                    let Const::Yes(span) = c else { unreachable!() };
+                    self.dcx().emit_err(ConstComptimeFn { span, attr_span });
+                }
+                // Good
+                hir::Constness::NotConst => {}
+            }
         }
+        constness
     }
 
     pub(super) fn lower_safety(&self, s: Safety, default: hir::Safety) -> hir::Safety {

compiler/rustc_attr_parsing/src/attributes/semantics.rs

@@ -23,6 +23,7 @@ impl NoArgsAttributeParser for ComptimeParser {
     const ALLOWED_TARGETS: AllowedTargets<'_> = AllowedTargets::AllowList(&[
         Allow(Target::Method(MethodKind::Inherent)),
         Allow(Target::Fn),
+        Allow(Target::Impl { of_trait: false }),
     ]);
     const STABILITY: AttributeStability = unstable!(rustc_attrs);
     const CREATE: fn(Span) -> AttributeKind = AttributeKind::RustcComptime;

compiler/rustc_builtin_macros/src/cfg_eval.rs

@@ -3,7 +3,7 @@ use core::ops::ControlFlow;
 use rustc_ast as ast;
 use rustc_ast::mut_visit::MutVisitor;
 use rustc_ast::visit::{AssocCtxt, Visitor};
-use rustc_ast::{Attribute, HasAttrs, HasTokens, NodeId, mut_visit, visit};
+use rustc_ast::{Attribute, HasTokens, NodeId, mut_visit, visit};
 use rustc_errors::PResult;
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_expand::config::StripUnconfigured;
@@ -67,7 +67,7 @@ fn has_cfg_or_cfg_attr(annotatable: &Annotatable) -> bool {
 }
 
 impl CfgEval<'_> {
-    fn configure<T: HasAttrs + HasTokens>(&mut self, node: T) -> Option<T> {
+    fn configure<T: HasTokens>(&mut self, node: T) -> Option<T> {
         self.0.configure(node)
     }