Port the #[linkage] attribute to the new attribute system

compiler/rustc_attr_parsing/src/attributes/link_attrs.rs

@@ -1,6 +1,6 @@
 use rustc_feature::{AttributeTemplate, template};
-use rustc_hir::attrs::AttributeKind;
 use rustc_hir::attrs::AttributeKind::{LinkName, LinkOrdinal, LinkSection};
+use rustc_hir::attrs::{AttributeKind, Linkage};
 use rustc_span::{Span, Symbol, sym};
 
 use crate::attributes::{
@@ -129,3 +129,77 @@ impl<S: Stage> SingleAttributeParser<S> for LinkOrdinalParser {
         Some(LinkOrdinal { ordinal, span: cx.attr_span })
     }
 }
+
+pub(crate) struct LinkageParser;
+
+impl<S: Stage> SingleAttributeParser<S> for LinkageParser {
+    const PATH: &[Symbol] = &[sym::linkage];
+
+    const ATTRIBUTE_ORDER: AttributeOrder = AttributeOrder::KeepOutermost;
+
+    const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Error;
+
+    const TEMPLATE: AttributeTemplate = template!(NameValueStr: [
+        "available_externally",
+        "common",
+        "extern_weak",
+        "external",
+        "internal",
+        "linkonce",
+        "linkonce_odr",
+        "weak",
+        "weak_odr",
+    ]);
+
+    fn convert(cx: &mut AcceptContext<'_, '_, S>, args: &ArgParser<'_>) -> Option<AttributeKind> {
+        let Some(name_value) = args.name_value() else {
+            cx.expected_name_value(cx.attr_span, Some(sym::linkage));
+            return None;
+        };
+
+        let Some(value) = name_value.value_as_str() else {
+            cx.expected_string_literal(name_value.value_span, Some(name_value.value_as_lit()));
+            return None;
+        };
+
+        // Use the names from src/llvm/docs/LangRef.rst here. Most types are only
+        // applicable to variable declarations and may not really make sense for
+        // Rust code in the first place but allow them anyway and trust that the
+        // user knows what they're doing. Who knows, unanticipated use cases may pop
+        // up in the future.
+        //
+        // ghost, dllimport, dllexport and linkonce_odr_autohide are not supported
+        // and don't have to be, LLVM treats them as no-ops.
+        let linkage = match value {
+            sym::available_externally => Linkage::AvailableExternally,
+            sym::common => Linkage::Common,
+            sym::extern_weak => Linkage::ExternalWeak,
+            sym::external => Linkage::External,
+            sym::internal => Linkage::Internal,
+            sym::linkonce => Linkage::LinkOnceAny,
+            sym::linkonce_odr => Linkage::LinkOnceODR,
+            sym::weak => Linkage::WeakAny,
+            sym::weak_odr => Linkage::WeakODR,
+
+            _ => {
+                cx.expected_specific_argument(
+                    name_value.value_span,
+                    vec![
+                        "available_externally",
+                        "common",
+                        "extern_weak",
+                        "external",
+                        "internal",
+                        "linkonce",
+                        "linkonce_odr",
+                        "weak",
+                        "weak_odr",
+                    ],
+                );
+                return None;
+            }
+        };
+
+        Some(AttributeKind::Linkage(linkage, cx.attr_span))
+    }
+}

compiler/rustc_attr_parsing/src/context.rs

@@ -27,7 +27,7 @@ use crate::attributes::dummy::DummyParser;
 use crate::attributes::inline::{InlineParser, RustcForceInlineParser};
 use crate::attributes::link_attrs::{
     ExportStableParser, FfiConstParser, FfiPureParser, LinkNameParser, LinkOrdinalParser,
-    LinkSectionParser, StdInternalSymbolParser,
+    LinkSectionParser, LinkageParser, StdInternalSymbolParser,
 };
 use crate::attributes::lint_helpers::{
     AsPtrParser, AutomaticallyDerivedParser, PassByValueParser, PubTransparentParser,
@@ -167,6 +167,7 @@ attribute_parsers!(
         Single<LinkNameParser>,
         Single<LinkOrdinalParser>,
         Single<LinkSectionParser>,
+        Single<LinkageParser>,
         Single<MustUseParser>,
         Single<OptimizeParser>,
         Single<PathAttributeParser>,

compiler/rustc_codegen_cranelift/src/constant.rs

@@ -281,8 +281,8 @@ fn data_id_for_static(
             .abi
             .bytes();
 
-        let linkage = if import_linkage == rustc_middle::mir::mono::Linkage::ExternalWeak
-            || import_linkage == rustc_middle::mir::mono::Linkage::WeakAny
+        let linkage = if import_linkage == rustc_hir::attrs::Linkage::ExternalWeak
+            || import_linkage == rustc_hir::attrs::Linkage::WeakAny
         {
             Linkage::Preemptible
         } else {
@@ -332,8 +332,8 @@ fn data_id_for_static(
 
     let linkage = if definition {
         crate::linkage::get_static_linkage(tcx, def_id)
-    } else if attrs.linkage == Some(rustc_middle::mir::mono::Linkage::ExternalWeak)
-        || attrs.linkage == Some(rustc_middle::mir::mono::Linkage::WeakAny)
+    } else if attrs.linkage == Some(rustc_hir::attrs::Linkage::ExternalWeak)
+        || attrs.linkage == Some(rustc_hir::attrs::Linkage::WeakAny)
     {
         Linkage::Preemptible
     } else {

compiler/rustc_codegen_cranelift/src/driver/aot.rs

@@ -18,12 +18,11 @@ use rustc_codegen_ssa::{
 use rustc_data_structures::profiling::SelfProfilerRef;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::sync::{IntoDynSyncSend, par_map};
+use rustc_hir::attrs::Linkage as RLinkage;
 use rustc_metadata::fs::copy_to_stdout;
 use rustc_middle::dep_graph::{WorkProduct, WorkProductId};
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
-use rustc_middle::mir::mono::{
-    CodegenUnit, Linkage as RLinkage, MonoItem, MonoItemData, Visibility,
-};
+use rustc_middle::mir::mono::{CodegenUnit, MonoItem, MonoItemData, Visibility};
 use rustc_session::Session;
 use rustc_session::config::{DebugInfo, OutFileName, OutputFilenames, OutputType};
 

compiler/rustc_codegen_cranelift/src/linkage.rs

@@ -1,4 +1,5 @@
-use rustc_middle::mir::mono::{Linkage as RLinkage, MonoItem, Visibility};
+use rustc_hir::attrs::Linkage as RLinkage;
+use rustc_middle::mir::mono::{MonoItem, Visibility};
 
 use crate::prelude::*;
 

compiler/rustc_codegen_gcc/src/base.rs

@@ -8,8 +8,8 @@ use rustc_codegen_ssa::ModuleCodegen;
 use rustc_codegen_ssa::base::maybe_create_entry_wrapper;
 use rustc_codegen_ssa::mono_item::MonoItemExt;
 use rustc_codegen_ssa::traits::DebugInfoCodegenMethods;
+use rustc_hir::attrs::Linkage;
 use rustc_middle::dep_graph;
-use rustc_middle::mir::mono::Linkage;
 #[cfg(feature = "master")]
 use rustc_middle::mir::mono::Visibility;
 use rustc_middle::ty::TyCtxt;

compiler/rustc_codegen_gcc/src/consts.rs

@@ -5,13 +5,13 @@ use rustc_abi::{self as abi, Align, HasDataLayout, Primitive, Size, WrappingRang
 use rustc_codegen_ssa::traits::{
     BaseTypeCodegenMethods, ConstCodegenMethods, StaticCodegenMethods,
 };
+use rustc_hir::attrs::Linkage;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, CodegenFnAttrs};
 use rustc_middle::mir::interpret::{
     self, ConstAllocation, ErrorHandled, Scalar as InterpScalar, read_target_uint,
 };
-use rustc_middle::mir::mono::Linkage;
 use rustc_middle::ty::layout::LayoutOf;
 use rustc_middle::ty::{self, Instance};
 use rustc_middle::{bug, span_bug};

compiler/rustc_codegen_gcc/src/mono_item.rs

@@ -1,11 +1,12 @@
 #[cfg(feature = "master")]
 use gccjit::{FnAttribute, VarAttribute};
 use rustc_codegen_ssa::traits::PreDefineCodegenMethods;
+use rustc_hir::attrs::Linkage;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_middle::bug;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
-use rustc_middle::mir::mono::{Linkage, Visibility};
+use rustc_middle::mir::mono::Visibility;
 use rustc_middle::ty::layout::{FnAbiOf, HasTypingEnv, LayoutOf};
 use rustc_middle::ty::{self, Instance, TypeVisitableExt};
 

compiler/rustc_codegen_llvm/src/base.rs

@@ -18,9 +18,10 @@ use rustc_codegen_ssa::base::maybe_create_entry_wrapper;
 use rustc_codegen_ssa::mono_item::MonoItemExt;
 use rustc_codegen_ssa::traits::*;
 use rustc_data_structures::small_c_str::SmallCStr;
+use rustc_hir::attrs::Linkage;
 use rustc_middle::dep_graph;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
-use rustc_middle::mir::mono::{Linkage, Visibility};
+use rustc_middle::mir::mono::Visibility;
 use rustc_middle::ty::TyCtxt;
 use rustc_session::config::DebugInfo;
 use rustc_span::Symbol;

compiler/rustc_codegen_llvm/src/consts.rs

@@ -4,14 +4,15 @@ use rustc_abi::{Align, HasDataLayout, Primitive, Scalar, Size, WrappingRange};
 use rustc_codegen_ssa::common;
 use rustc_codegen_ssa::traits::*;
 use rustc_hir::LangItem;
+use rustc_hir::attrs::Linkage;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, CodegenFnAttrs};
 use rustc_middle::mir::interpret::{
     Allocation, ConstAllocation, ErrorHandled, InitChunk, Pointer, Scalar as InterpScalar,
     read_target_uint,
 };
-use rustc_middle::mir::mono::{Linkage, MonoItem};
+use rustc_middle::mir::mono::MonoItem;
 use rustc_middle::ty::layout::{HasTypingEnv, LayoutOf};
 use rustc_middle::ty::{self, Instance};
 use rustc_middle::{bug, span_bug};

compiler/rustc_codegen_llvm/src/mono_item.rs

@@ -1,8 +1,9 @@
 use rustc_codegen_ssa::traits::*;
+use rustc_hir::attrs::Linkage;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_middle::bug;
-use rustc_middle::mir::mono::{Linkage, Visibility};
+use rustc_middle::mir::mono::Visibility;
 use rustc_middle::ty::layout::{FnAbiOf, HasTypingEnv, LayoutOf};
 use rustc_middle::ty::{self, Instance, TypeVisitableExt};
 use rustc_session::config::CrateType;

compiler/rustc_codegen_ssa/src/back/symbol_export.rs

@@ -306,7 +306,8 @@ fn exported_generic_symbols_provider_local<'tcx>(
     let mut symbols: Vec<_> = vec![];
 
     if tcx.local_crate_exports_generics() {
-        use rustc_middle::mir::mono::{Linkage, MonoItem, Visibility};
+        use rustc_hir::attrs::Linkage;
+        use rustc_middle::mir::mono::{MonoItem, Visibility};
         use rustc_middle::ty::InstanceKind;
 
         // Normally, we require that shared monomorphizations are not hidden,

compiler/rustc_codegen_ssa/src/codegen_attrs.rs

@@ -11,7 +11,6 @@ use rustc_hir::{self as hir, Attribute, LangItem, find_attr, lang_items};
 use rustc_middle::middle::codegen_fn_attrs::{
     CodegenFnAttrFlags, CodegenFnAttrs, PatchableFunctionEntry,
 };
-use rustc_middle::mir::mono::Linkage;
 use rustc_middle::query::Providers;
 use rustc_middle::span_bug;
 use rustc_middle::ty::{self as ty, TyCtxt};
@@ -26,31 +25,6 @@ use crate::target_features::{
     check_target_feature_trait_unsafe, check_tied_features, from_target_feature_attr,
 };
 
-fn linkage_by_name(tcx: TyCtxt<'_>, def_id: LocalDefId, name: &str) -> Linkage {
-    use rustc_middle::mir::mono::Linkage::*;
-
-    // Use the names from src/llvm/docs/LangRef.rst here. Most types are only
-    // applicable to variable declarations and may not really make sense for
-    // Rust code in the first place but allow them anyway and trust that the
-    // user knows what they're doing. Who knows, unanticipated use cases may pop
-    // up in the future.
-    //
-    // ghost, dllimport, dllexport and linkonce_odr_autohide are not supported
-    // and don't have to be, LLVM treats them as no-ops.
-    match name {
-        "available_externally" => AvailableExternally,
-        "common" => Common,
-        "extern_weak" => ExternalWeak,
-        "external" => External,
-        "internal" => Internal,
-        "linkonce" => LinkOnceAny,
-        "linkonce_odr" => LinkOnceODR,
-        "weak" => WeakAny,
-        "weak_odr" => WeakODR,
-        _ => tcx.dcx().span_fatal(tcx.def_span(def_id), "invalid linkage specified"),
-    }
-}
-
 /// In some cases, attributes are only valid on functions, but it's the `check_attr`
 /// pass that checks that they aren't used anywhere else, rather than this module.
 /// In these cases, we bail from performing further checks that are only meaningful for
@@ -103,13 +77,6 @@ fn parse_instruction_set_attr(tcx: TyCtxt<'_>, attr: &Attribute) -> Option<Instr
     }
 }
 
-// FIXME(jdonszelmann): remove when linkage becomes a parsed attr
-fn parse_linkage_attr(tcx: TyCtxt<'_>, did: LocalDefId, attr: &Attribute) -> Option<Linkage> {
-    let val = attr.value_str()?;
-    let linkage = linkage_by_name(tcx, did, val.as_str());
-    Some(linkage)
-}
-
 // FIXME(jdonszelmann): remove when no_sanitize becomes a parsed attr
 fn parse_no_sanitize_attr(tcx: TyCtxt<'_>, attr: &Attribute) -> Option<SanitizerSet> {
     let list = attr.meta_item_list()?;
@@ -332,6 +299,28 @@ fn process_builtin_attrs(
                 AttributeKind::StdInternalSymbol(_) => {
                     codegen_fn_attrs.flags |= CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL
                 }
+                AttributeKind::Linkage(linkage, _) => {
+                    let linkage = Some(*linkage);
+
+                    if tcx.is_foreign_item(did) {
+                        codegen_fn_attrs.import_linkage = linkage;
+
+                        if tcx.is_mutable_static(did.into()) {
+                            let mut diag = tcx.dcx().struct_span_err(
+                                attr.span(),
+                                "extern mutable statics are not allowed with `#[linkage]`",
+                            );
+                            diag.note(
+                                "marking the extern static mutable would allow changing which \
+                                symbol the static references rather than make the target of the \
+                                symbol mutable",
+                            );
+                            diag.emit();
+                        }
+                    } else {
+                        codegen_fn_attrs.linkage = linkage;
+                    }
+                }
                 _ => {}
             }
         }
@@ -349,28 +338,6 @@ fn process_builtin_attrs(
                 codegen_fn_attrs.flags |= CodegenFnAttrFlags::ALLOCATOR_ZEROED
             }
             sym::thread_local => codegen_fn_attrs.flags |= CodegenFnAttrFlags::THREAD_LOCAL,
-            sym::linkage => {
-                let linkage = parse_linkage_attr(tcx, did, attr);
-
-                if tcx.is_foreign_item(did) {
-                    codegen_fn_attrs.import_linkage = linkage;
-
-                    if tcx.is_mutable_static(did.into()) {
-                        let mut diag = tcx.dcx().struct_span_err(
-                            attr.span(),
-                            "extern mutable statics are not allowed with `#[linkage]`",
-                        );
-                        diag.note(
-                            "marking the extern static mutable would allow changing which \
-                            symbol the static references rather than make the target of the \
-                            symbol mutable",
-                        );
-                        diag.emit();
-                    }
-                } else {
-                    codegen_fn_attrs.linkage = linkage;
-                }
-            }
             sym::no_sanitize => {
                 interesting_spans.no_sanitize = Some(attr.span());
                 codegen_fn_attrs.no_sanitize |=

compiler/rustc_codegen_ssa/src/mir/naked_asm.rs

@@ -1,6 +1,6 @@
 use rustc_abi::{BackendRepr, Float, Integer, Primitive, RegKind};
-use rustc_hir::attrs::InstructionSetAttr;
-use rustc_middle::mir::mono::{Linkage, MonoItemData, Visibility};
+use rustc_hir::attrs::{InstructionSetAttr, Linkage};
+use rustc_middle::mir::mono::{MonoItemData, Visibility};
 use rustc_middle::mir::{InlineAsmOperand, START_BLOCK};
 use rustc_middle::ty::layout::{FnAbiOf, LayoutOf, TyAndLayout};
 use rustc_middle::ty::{Instance, Ty, TyCtxt, TypeVisitableExt};

compiler/rustc_codegen_ssa/src/mono_item.rs

@@ -1,5 +1,6 @@
+use rustc_hir::attrs::Linkage;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
-use rustc_middle::mir::mono::{Linkage, MonoItem, MonoItemData, Visibility};
+use rustc_middle::mir::mono::{MonoItem, MonoItemData, Visibility};
 use rustc_middle::ty::layout::HasTyCtxt;
 use tracing::debug;
 

compiler/rustc_codegen_ssa/src/traits/declare.rs

@@ -1,5 +1,6 @@
+use rustc_hir::attrs::Linkage;
 use rustc_hir::def_id::DefId;
-use rustc_middle::mir::mono::{Linkage, Visibility};
+use rustc_middle::mir::mono::Visibility;
 use rustc_middle::ty::Instance;
 
 pub trait PreDefineCodegenMethods<'tcx> {