Auto merge of #165056 - JonathanBrouwer:rollup-ZFCUK9j, r=JonathanBrouwer

Rollup of 21 pull requests

Successful merges:

 - #159580 (Reject cfg on expressions that cannot be safely removed)
 - #162597 (raise ambiguity error on attribute macro that could be tool attribute)
 - #162808 (Enable `--generate-link-to-definition` rustdoc option on std docs)
 - #163059 (Recover invalid return type until `{`, `}` or `;`)
 - #163672 (Use runCodeGen Abstraction for new LLVM)
 - #164028 (Add a future incompat warning for #[no_link])
 - #164188 (Suggest adding lifetime for `dyn Trait` in return type)
 - #164345 (fix: handle `false` in root contexts)
 - #164494 (drop ands which are a superset of other ands)
 - #164785 (delegation: emit error when there is no field for `Self` mapping)
 - #164799 (Don't use `IntoIterator` in parallel API)
 - #164871 (Refactor call argument codegen)
 - #164648 (parse inline and rustc_force_inline with same parser)
 - #164811 (fix: Prevent ICE when comparing EII impl against generic declaration)
 - #164900 (make tool_attrs method to retrieve tool attributes.)
 - #164993 (copy_nonoverlapping: dont skip ovelrap check when src is fully uninit)
 - #164996 (miri: add missing alignment check in write_bytes)
 - #165012 (Remove Span::eq_ctxt())
 - #165013 ([tiny] Add missing backticks around lifetime name)
 - #165024 (rustdoc-search: rank re-export lower)
 - #165028 (Update enzyme to fix one bug related to higher-order derivatives)

Author: bors

compiler/rustc_ast_lowering/src/lib.rs

@@ -1330,7 +1330,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                                 .gen_args
                                 .as_ref()
                                 .map_or(constraint.ident.span, |args| args.span());
-                            if bound_end_span.eq_ctxt(constraint.span) {
+                            if bound_end_span.ctxt() == constraint.span.ctxt() {
                                 Some(self.tcx.sess.source_map().next_point(bound_end_span))
                             } else {
                                 None

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -1703,7 +1703,7 @@ impl Visitor<'_> for AstValidator<'_> {
                 }
                 if ident.name == kw::Underscore
                     && !matches!(item.vis.kind, VisibilityKind::Inherited)
-                    && ident.span.eq_ctxt(item.vis.span)
+                    && ident.span.ctxt() == item.vis.span.ctxt()
                 {
                     self.lint_buffer.buffer_lint(
                         UNUSED_VISIBILITIES,

compiler/rustc_attr_ir/src/attr.rs

@@ -6,7 +6,7 @@ use rustc_ast::{AttrStyle, DelimArgs, MetaItemLit, ast, join_path_idents};
 use rustc_data_structures::stable_hash::{StableHash, StableHashCtxt, StableHasher};
 use rustc_error_messages::{DiagArgValue, IntoDiagArg};
 use rustc_macros::{Decodable, Encodable, StableHash};
-use rustc_span::{AttrId, DUMMY_SP, Ident, Span, Symbol, sym};
+use rustc_span::{AttrId, DUMMY_SP, Ident, Span, Symbol};
 use smallvec::SmallVec;
 use thin_vec::ThinVec;
 
@@ -72,7 +72,6 @@ pub struct AttrItem {
     // Not lowered to hir::Path because we have no NodeId to resolve to.
     pub path: AttrPath,
     pub args: AttrArgs,
-    pub id: HashIgnoredAttrId,
     /// Denotes if the attribute decorates the following construct (outer)
     /// or the construct this attribute is contained within (inner).
     pub style: AttrStyle,
@@ -110,16 +109,25 @@ pub enum Attribute {
     /// [`AttributeKind::Stability`] attribute. Most `Attribute` variants do have a [`Span`] field,
     /// though, mostly for the purpose of generating diagnostics later in the compilation process.
     Parsed(AttributeKind),
-    /// Represents non built-in attributes, which are not converted into a parsed form.
+
+    /// A tool attribute.
+    ///
+    /// Tool attributes, with the exception of diagnostic attributes, are not converted into a
+    /// parsed form.
+    Tool(Box<AttrItem>),
+
+    /// A derive helper attribute.
     ///
-    /// This is the case for custom tool attributes and derive helper attributes.
-    Unparsed(Box<AttrItem>),
+    /// Derive helper attributes serve no use beyond macro expansion, but they are useful to
+    /// consumers of `rustdoc-json`, so we keep them around. See
+    /// <https://github.com/rust-lang/rust/issues/157107> for context.
+    DeriveHelper(Box<AttrItem>),
 }
 
 impl Attribute {
     pub fn value_lit(&self) -> Option<&MetaItemLit> {
         match &self {
-            Attribute::Unparsed(n) => match n.as_ref() {
+            Attribute::Tool(n) | Attribute::DeriveHelper(n) => match n.as_ref() {
                 AttrItem { args: AttrArgs::Eq { eq_span: _, expr }, .. } => Some(expr),
                 _ => None,
             },
@@ -129,7 +137,9 @@ impl Attribute {
 
     pub fn is_prefix_attr_for_suggestions(&self) -> bool {
         match self {
-            Attribute::Unparsed(attr) => attr.span.desugaring_kind().is_none(),
+            Attribute::Tool(attr) | Attribute::DeriveHelper(attr) => {
+                attr.span.desugaring_kind().is_none()
+            }
             // Other parsed attributes that can appear on expressions originate from source and
             // should make suggestions treat the expression like a prefixed form.
             Attribute::Parsed(_) => true,
@@ -141,7 +151,7 @@ impl AttributeExt for Attribute {
     #[inline]
     fn meta_item_list(&self) -> Option<ThinVec<ast::MetaItemInner>> {
         match &self {
-            Attribute::Unparsed(n) => match n.as_ref() {
+            Attribute::Tool(n) | Attribute::DeriveHelper(n) => match n.as_ref() {
                 AttrItem { args: AttrArgs::Delimited(d), .. } => {
                     ast::MetaItemKind::list_from_tokens(d.tokens.clone())
                 }
@@ -165,21 +175,23 @@ impl AttributeExt for Attribute {
     #[inline]
     fn name(&self) -> Option<Symbol> {
         match &self {
-            Attribute::Unparsed(n) => {
+            Attribute::DeriveHelper(n) => {
                 if let [ident] = n.path.segments.as_ref() {
                     Some(*ident)
                 } else {
                     None
                 }
             }
-            _ => None,
+            Attribute::Parsed(..) => None,
+            // Tools are never single segment attributes
+            Attribute::Tool(..) => None,
         }
     }
 
     #[inline]
     fn path_matches(&self, name: &[Symbol]) -> bool {
         match &self {
-            Attribute::Unparsed(n) => n.path.segments.iter().eq(name),
+            Attribute::Tool(n) | Attribute::DeriveHelper(n) => n.path.segments.iter().eq(name),
             _ => false,
         }
     }
@@ -196,7 +208,7 @@ impl AttributeExt for Attribute {
     #[inline]
     fn is_word(&self) -> bool {
         match &self {
-            Attribute::Unparsed(n) => {
+            Attribute::Tool(n) | Attribute::DeriveHelper(n) => {
                 matches!(n.args, AttrArgs::Empty)
             }
             _ => false,
@@ -206,14 +218,16 @@ impl AttributeExt for Attribute {
     #[inline]
     fn symbol_path(&self) -> Option<SmallVec<[Symbol; 1]>> {
         match &self {
-            Attribute::Unparsed(n) => Some(n.path.segments.iter().copied().collect()),
+            Attribute::Tool(n) | Attribute::DeriveHelper(n) => {
+                Some(n.path.segments.iter().copied().collect())
+            }
             _ => None,
         }
     }
 
     fn path_span(&self) -> Option<Span> {
         match &self {
-            Attribute::Unparsed(attr) => Some(attr.path.span),
+            Attribute::Tool(attr) | Attribute::DeriveHelper(attr) => Some(attr.path.span),
             Attribute::Parsed(_) => None,
         }
     }
@@ -239,9 +253,6 @@ impl AttributeExt for Attribute {
     fn doc_resolution_scope(&self) -> Option<AttrStyle> {
         match self {
             Attribute::Parsed(AttributeKind::DocComment { style, .. }) => Some(*style),
-            Attribute::Unparsed(attr) if self.has_name(sym::doc) && self.value_str().is_some() => {
-                Some(attr.style)
-            }
             _ => None,
         }
     }

compiler/rustc_attr_ir/src/lib.rs

@@ -132,7 +132,7 @@ macro_rules! find_attr {
                     $crate::Attribute::Parsed($pattern) $(if $guard)? => {
                         break 'done Some($e);
                     }
-                    $crate::Attribute::Unparsed(..) => {}
+                    $crate::Attribute::Tool(..) | $crate::Attribute::DeriveHelper(..)  => {}
                     // In lint emitting, there's a specific exception for this warning.
                     // It's not usually emitted from inside macros from other crates
                     // (see https://github.com/rust-lang/rust/issues/110613)