Rollup merge of #150072 - Bryntet:parse_no_link, r=JonathanBrouwer

Port #[no_link] to use attribute parser

Adds `#[no_link]` to the attribute parser, as well as adds tests making sure to FCW warn on `field`, `arm`, and `macrodef `

compiler/rustc_attr_parsing/src/attributes/mod.rs

@@ -47,6 +47,7 @@
 pub(crate) mod macro_attrs;
 pub(crate) mod must_use;
 pub(crate) mod no_implicit_prelude;
+pub(crate) mod no_link;
 pub(crate) mod non_exhaustive;
 pub(crate) mod path;
 pub(crate) mod pin_v2;

compiler/rustc_attr_parsing/src/attributes/no_link.rs

@@ -0,0 +1,14 @@
+use super::prelude::*;
+
+pub(crate) struct NoLinkParser;
+impl<S: Stage> NoArgsAttributeParser<S> for NoLinkParser {
+    const PATH: &[Symbol] = &[sym::no_link];
+    const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Warn;
+    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[
+        Allow(Target::ExternCrate),
+        Warn(Target::Field),
+        Warn(Target::Arm),
+        Warn(Target::MacroDef),
+    ]);
+    const CREATE: fn(Span) -> AttributeKind = |_| AttributeKind::NoLink;
+}

compiler/rustc_attr_parsing/src/context.rs

@@ -50,6 +50,7 @@
 };
 use crate::attributes::must_use::MustUseParser;
 use crate::attributes::no_implicit_prelude::NoImplicitPreludeParser;
+use crate::attributes::no_link::NoLinkParser;
 use crate::attributes::non_exhaustive::NonExhaustiveParser;
 use crate::attributes::path::PathParser as PathAttributeParser;
 use crate::attributes::pin_v2::PinV2Parser;
@@ -241,6 +242,7 @@ mod late {
         Single<WithoutArgs<MayDangleParser>>,
         Single<WithoutArgs<NoCoreParser>>,
         Single<WithoutArgs<NoImplicitPreludeParser>>,
+        Single<WithoutArgs<NoLinkParser>>,
         Single<WithoutArgs<NoMangleParser>>,
         Single<WithoutArgs<NoStdParser>>,
         Single<WithoutArgs<NonExhaustiveParser>>,

compiler/rustc_hir/src/attrs/data_structures.rs

@@ -803,6 +803,9 @@ pub enum AttributeKind {
     /// Represents `#[no_implicit_prelude]`
     NoImplicitPrelude(Span),
 
+    /// Represents `#[no_link]`
+    NoLink,
+
     /// Represents `#[no_mangle]`
     NoMangle(Span),
 

compiler/rustc_hir/src/attrs/encode_cross_crate.rs

@@ -70,6 +70,7 @@ pub fn encode_cross_crate(&self) -> EncodeCrossCrate {
             Naked(..) => No,
             NoCore(..) => No,
             NoImplicitPrelude(..) => No,
+            NoLink => No,
             NoMangle(..) => Yes, // Needed for rustdoc
             NoStd(..) => No,
             NonExhaustive(..) => Yes, // Needed for rustdoc

compiler/rustc_passes/messages.ftl

@@ -240,11 +240,6 @@ passes_has_incoherent_inherent_impl =
     `rustc_has_incoherent_inherent_impls` attribute should be applied to types or traits
     .label = only adts, extern types and traits are supported
 
-passes_ignored_attr_with_macro =
-    `#[{$sym}]` is ignored on struct fields, match arms and macro defs
-    .warn = {-passes_previously_accepted}
-    .note = {-passes_see_issue(issue: "80564")}
-
 passes_ignored_derived_impls =
     `{$name}` has {$trait_list_len ->
       [one] a derived impl
@@ -379,10 +374,6 @@ passes_must_not_suspend =
     `must_not_suspend` attribute should be applied to a struct, enum, union, or trait
     .label = is not a struct, enum, union, or trait
 
-passes_no_link =
-    attribute should be applied to an `extern crate` item
-    .label = not an `extern crate` item
-
 passes_no_main_function =
     `main` function not found in crate `{$crate_name}`
     .here_is_main = here is a function named `main`

compiler/rustc_passes/src/check_attr.rs

@@ -254,6 +254,7 @@ fn check_attributes(
                     | AttributeKind::LinkSection { .. }
                     | AttributeKind::MacroUse { .. }
                     | AttributeKind::MacroEscape( .. )
+                    | AttributeKind::NoLink
                     | AttributeKind::RustcLayoutScalarValidRangeStart(..)
                     | AttributeKind::RustcLayoutScalarValidRangeEnd(..)
                     | AttributeKind::RustcScalableVector { .. }
@@ -303,7 +304,6 @@ fn check_attributes(
                             self.check_diagnostic_on_const(attr.span(), hir_id, target, item)
                         }
                         [sym::thread_local, ..] => self.check_thread_local(attr, span, target),
-                        [sym::no_link, ..] => self.check_no_link(hir_id, attr, span, target),
                         [sym::rustc_no_implicit_autorefs, ..] => {
                             self.check_applied_to_fn_or_method(hir_id, attr.span(), span, target)
                         }
@@ -457,15 +457,6 @@ fn check_attributes(
         self.check_mix_no_mangle_export(hir_id, attrs);
     }
 
-    fn inline_attr_str_error_with_macro_def(&self, hir_id: HirId, attr_span: Span, sym: &str) {
-        self.tcx.emit_node_span_lint(
-            UNUSED_ATTRIBUTES,
-            hir_id,
-            attr_span,
-            errors::IgnoredAttrWithMacro { sym },
-        );
-    }
-
     fn check_eii_impl(&self, impls: &[EiiImpl], target: Target) {
         for EiiImpl { span, inner_span, eii_macro, impl_marked_unsafe, is_default: _ } in impls {
             match target {
@@ -1199,23 +1190,6 @@ fn check_link(&self, hir_id: HirId, attr_span: Span, span: Span, target: Target)
         );
     }
 
-    /// Checks if `#[no_link]` is applied to an `extern crate`.
-    fn check_no_link(&self, hir_id: HirId, attr: &Attribute, span: Span, target: Target) {
-        match target {
-            Target::ExternCrate => {}
-            // FIXME(#80564): We permit struct fields, match arms and macro defs to have an
-            // `#[no_link]` attribute with just a lint, because we previously
-            // erroneously allowed it and some crates used it accidentally, to be compatible
-            // with crates depending on them, we can't throw an error here.
-            Target::Field | Target::Arm | Target::MacroDef => {
-                self.inline_attr_str_error_with_macro_def(hir_id, attr.span(), "no_link");
-            }
-            _ => {
-                self.dcx().emit_err(errors::NoLink { attr_span: attr.span(), span });
-            }
-        }
-    }
-
     /// Checks if `#[rustc_legacy_const_generics]` is applied to a function and has a valid argument.
     fn check_rustc_legacy_const_generics(
         &self,

compiler/rustc_passes/src/errors.rs

@@ -80,12 +80,6 @@ pub(crate) struct OuterCrateLevelAttrSuggestion {
 #[diag(passes_inner_crate_level_attr)]
 pub(crate) struct InnerCrateLevelAttr;
 
-#[derive(LintDiagnostic)]
-#[diag(passes_ignored_attr_with_macro)]
-pub(crate) struct IgnoredAttrWithMacro<'a> {
-    pub sym: &'a str,
-}
-
 #[derive(Diagnostic)]
 #[diag(passes_should_be_applied_to_fn)]
 pub(crate) struct AttrShouldBeAppliedToFn {
@@ -254,15 +248,6 @@ pub(crate) struct Link {
     pub span: Option<Span>,
 }
 
-#[derive(Diagnostic)]
-#[diag(passes_no_link)]
-pub(crate) struct NoLink {
-    #[primary_span]
-    pub attr_span: Span,
-    #[label]
-    pub span: Span,
-}
-
 #[derive(Diagnostic)]
 #[diag(passes_rustc_legacy_const_generics_only)]
 pub(crate) struct RustcLegacyConstGenericsOnly {