Rollup of 5 pull requests

Cargo.lock

@@ -3204,9 +3204,11 @@ dependencies = [
  "rand",
  "rand_xoshiro",
  "rustc_data_structures",
+ "rustc_feature",
  "rustc_index",
  "rustc_macros",
  "rustc_serialize",
+ "rustc_span",
  "tracing",
 ]
 
@@ -3749,11 +3751,11 @@ dependencies = [
 name = "rustc_hir_pretty"
 version = "0.0.0"
 dependencies = [
+ "rustc_abi",
  "rustc_ast",
  "rustc_ast_pretty",
  "rustc_hir",
  "rustc_span",
- "rustc_target",
 ]
 
 [[package]]
@@ -3938,14 +3940,14 @@ dependencies = [
 name = "rustc_lint_defs"
 version = "0.0.0"
 dependencies = [
+ "rustc_abi",
  "rustc_ast",
  "rustc_data_structures",
  "rustc_error_messages",
  "rustc_hir",
  "rustc_macros",
  "rustc_serialize",
  "rustc_span",
- "rustc_target",
  "serde",
 ]
 
@@ -4054,6 +4056,7 @@ version = "0.0.0"
 dependencies = [
  "either",
  "itertools",
+ "rustc_abi",
  "rustc_apfloat",
  "rustc_arena",
  "rustc_ast",
@@ -4069,7 +4072,6 @@ dependencies = [
  "rustc_pattern_analysis",
  "rustc_session",
  "rustc_span",
- "rustc_target",
  "rustc_trait_selection",
  "tracing",
 ]

compiler/rustc_abi/Cargo.toml

@@ -9,9 +9,11 @@ bitflags = "2.4.1"
 rand = { version = "0.8.4", default-features = false, optional = true }
 rand_xoshiro = { version = "0.6.0", optional = true }
 rustc_data_structures = { path = "../rustc_data_structures", optional = true  }
+rustc_feature = { path = "../rustc_feature", optional = true }
 rustc_index = { path = "../rustc_index", default-features = false }
 rustc_macros = { path = "../rustc_macros", optional = true }
 rustc_serialize = { path = "../rustc_serialize", optional = true  }
+rustc_span = { path = "../rustc_span", optional = true }
 tracing = "0.1"
 # tidy-alphabetical-end
 
@@ -22,8 +24,10 @@ default = ["nightly", "randomize"]
 # without depending on rustc_data_structures, rustc_macros and rustc_serialize
 nightly = [
     "dep:rustc_data_structures",
+    "dep:rustc_feature",
     "dep:rustc_macros",
     "dep:rustc_serialize",
+    "dep:rustc_span",
     "rustc_index/nightly",
 ]
 randomize = ["dep:rand", "dep:rand_xoshiro", "nightly"]

compiler/rustc_target/src/spec/abi/mod.rs → compiler/rustc_abi/src/extern_abi/mod.rs

@@ -7,9 +7,11 @@ use rustc_span::{Span, Symbol};
 #[cfg(test)]
 mod tests;
 
+use ExternAbi as Abi;
+
 #[derive(PartialEq, Eq, PartialOrd, Ord, Hash, Clone, Copy, Debug)]
 #[derive(HashStable_Generic, Encodable, Decodable)]
-pub enum Abi {
+pub enum ExternAbi {
     // Some of the ABIs come first because every time we add a new ABI, we have to re-bless all the
     // hashing tests. These are used in many places, so giving them stable values reduces test
     // churn. The specific values are meaningless.

compiler/rustc_abi/src/lib.rs

@@ -1,6 +1,7 @@
 // tidy-alphabetical-start
 #![cfg_attr(feature = "nightly", allow(internal_features))]
 #![cfg_attr(feature = "nightly", doc(rust_logo))]
+#![cfg_attr(feature = "nightly", feature(assert_matches))]
 #![cfg_attr(feature = "nightly", feature(rustc_attrs))]
 #![cfg_attr(feature = "nightly", feature(rustdoc_internals))]
 #![cfg_attr(feature = "nightly", feature(step_trait))]
@@ -28,8 +29,15 @@ mod layout;
 #[cfg(test)]
 mod tests;
 
+#[cfg(feature = "nightly")]
+mod extern_abi;
+
 pub use callconv::{Heterogeneous, HomogeneousAggregate, Reg, RegKind};
 #[cfg(feature = "nightly")]
+pub use extern_abi::{
+    AbiDisabled, AbiUnsupported, ExternAbi, all_names, enabled_names, is_enabled, is_stable, lookup,
+};
+#[cfg(feature = "nightly")]
 pub use layout::{FIRST_VARIANT, FieldIdx, Layout, TyAbiInterface, TyAndLayout, VariantIdx};
 pub use layout::{LayoutCalculator, LayoutCalculatorError};
 

compiler/rustc_ast/src/ast.rs

@@ -2810,6 +2810,8 @@ pub struct ModSpans {
 /// E.g., `extern { .. }` or `extern "C" { .. }`.
 #[derive(Clone, Encodable, Decodable, Debug)]
 pub struct ForeignMod {
+    /// Span of the `extern` keyword.
+    pub extern_span: Span,
     /// `unsafe` keyword accepted syntactically for macro DSLs, but not
     /// semantically by Rust.
     pub safety: Safety,

compiler/rustc_ast/src/mut_visit.rs

@@ -525,7 +525,7 @@ pub fn walk_ty<T: MutVisitor>(vis: &mut T, ty: &mut P<Ty>) {
 }
 
 fn walk_foreign_mod<T: MutVisitor>(vis: &mut T, foreign_mod: &mut ForeignMod) {
-    let ForeignMod { safety, abi: _, items } = foreign_mod;
+    let ForeignMod { extern_span: _, safety, abi: _, items } = foreign_mod;
     visit_safety(vis, safety);
     items.flat_map_in_place(|item| vis.flat_map_foreign_item(item));
 }

compiler/rustc_ast/src/visit.rs

@@ -366,7 +366,7 @@ impl WalkItemKind for ItemKind {
                 }
                 ModKind::Unloaded => {}
             },
-            ItemKind::ForeignMod(ForeignMod { safety: _, abi: _, items }) => {
+            ItemKind::ForeignMod(ForeignMod { extern_span: _, safety: _, abi: _, items }) => {
                 walk_list!(visitor, visit_foreign_item, items);
             }
             ItemKind::GlobalAsm(asm) => try_visit!(visitor.visit_inline_asm(asm)),

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -677,9 +677,8 @@ impl<'a> AstValidator<'a> {
                 Self::check_decl_no_pat(&bfty.decl, |span, _, _| {
                     self.dcx().emit_err(errors::PatternFnPointer { span });
                 });
-                if let Extern::Implicit(_) = bfty.ext {
-                    let sig_span = self.sess.source_map().next_point(ty.span.shrink_to_lo());
-                    self.maybe_lint_missing_abi(sig_span, ty.id);
+                if let Extern::Implicit(extern_span) = bfty.ext {
+                    self.maybe_lint_missing_abi(extern_span, ty.id);
                 }
             }
             TyKind::TraitObject(bounds, ..) => {
@@ -953,7 +952,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                 walk_list!(self, visit_attribute, &item.attrs);
                 return; // Avoid visiting again.
             }
-            ItemKind::ForeignMod(ForeignMod { abi, safety, .. }) => {
+            ItemKind::ForeignMod(ForeignMod { extern_span, abi, safety, .. }) => {
                 self.with_in_extern_mod(*safety, |this| {
                     let old_item = mem::replace(&mut this.extern_mod, Some(item.span));
                     this.visibility_not_permitted(
@@ -977,7 +976,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                     }
 
                     if abi.is_none() {
-                        this.maybe_lint_missing_abi(item.span, item.id);
+                        this.maybe_lint_missing_abi(*extern_span, item.id);
                     }
                     visit::walk_item(this, item);
                     this.extern_mod = old_item;
@@ -1350,13 +1349,13 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
         if let FnKind::Fn(
             _,
             _,
-            FnSig { span: sig_span, header: FnHeader { ext: Extern::Implicit(_), .. }, .. },
+            FnSig { header: FnHeader { ext: Extern::Implicit(extern_span), .. }, .. },
             _,
             _,
             _,
         ) = fk
         {
-            self.maybe_lint_missing_abi(*sig_span, id);
+            self.maybe_lint_missing_abi(*extern_span, id);
         }
 
         // Functions without bodies cannot have patterns.

compiler/rustc_hir_analysis/src/hir_ty_lowering/bounds.rs

@@ -168,12 +168,6 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             match hir_bound {
                 hir::GenericBound::Trait(poly_trait_ref) => {
                     let hir::TraitBoundModifiers { constness, polarity } = poly_trait_ref.modifiers;
-                    let polarity = match polarity {
-                        rustc_ast::BoundPolarity::Positive => ty::PredicatePolarity::Positive,
-                        rustc_ast::BoundPolarity::Negative(_) => ty::PredicatePolarity::Negative,
-                        rustc_ast::BoundPolarity::Maybe(_) => continue,
-                    };
-
                     let _ = self.lower_poly_trait_ref(
                         &poly_trait_ref.trait_ref,
                         poly_trait_ref.span,

compiler/rustc_hir_analysis/src/hir_ty_lowering/dyn_compatibility.rs

@@ -51,7 +51,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
                 &trait_bound.trait_ref,
                 trait_bound.span,
                 hir::BoundConstness::Never,
-                ty::PredicatePolarity::Positive,
+                hir::BoundPolarity::Positive,
                 dummy_self,
                 &mut bounds,
                 PredicateFilter::SelfOnly,

compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs

@@ -668,7 +668,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
         trait_ref: &hir::TraitRef<'tcx>,
         span: Span,
         constness: hir::BoundConstness,
-        polarity: ty::PredicatePolarity,
+        polarity: hir::BoundPolarity,
         self_ty: Ty<'tcx>,
         bounds: &mut Bounds<'tcx>,
         predicate_filter: PredicateFilter,
@@ -690,15 +690,6 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             Some(self_ty),
         );
 
-        if let hir::BoundConstness::Always(span) | hir::BoundConstness::Maybe(span) = constness
-            && !self.tcx().is_const_trait(trait_def_id)
-        {
-            self.dcx().emit_err(crate::errors::ConstBoundForNonConstTrait {
-                span,
-                modifier: constness.as_str(),
-            });
-        }
-
         let tcx = self.tcx();
         let bound_vars = tcx.late_bound_vars(trait_ref.hir_ref_id);
         debug!(?bound_vars);
@@ -708,6 +699,36 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             bound_vars,
         );
 
+        let polarity = match polarity {
+            rustc_ast::BoundPolarity::Positive => ty::PredicatePolarity::Positive,
+            rustc_ast::BoundPolarity::Negative(_) => ty::PredicatePolarity::Negative,
+            rustc_ast::BoundPolarity::Maybe(_) => {
+                // Validate associated type at least. We may want to reject these
+                // outright in the future...
+                for constraint in trait_segment.args().constraints {
+                    let _ = self.lower_assoc_item_constraint(
+                        trait_ref.hir_ref_id,
+                        poly_trait_ref,
+                        constraint,
+                        &mut Default::default(),
+                        &mut Default::default(),
+                        constraint.span,
+                        predicate_filter,
+                    );
+                }
+                return arg_count;
+            }
+        };
+
+        if let hir::BoundConstness::Always(span) | hir::BoundConstness::Maybe(span) = constness
+            && !self.tcx().is_const_trait(trait_def_id)
+        {
+            self.dcx().emit_err(crate::errors::ConstBoundForNonConstTrait {
+                span,
+                modifier: constness.as_str(),
+            });
+        }
+
         match predicate_filter {
             PredicateFilter::All
             | PredicateFilter::SelfOnly
@@ -763,11 +784,11 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             // since we should have emitted an error for them earlier, and they
             // would not be well-formed!
             if polarity != ty::PredicatePolarity::Positive {
-                assert!(
-                    self.dcx().has_errors().is_some(),
+                self.dcx().span_delayed_bug(
+                    constraint.span,
                     "negative trait bounds should not have assoc item constraints",
                 );
-                continue;
+                break;
             }
 
             // Specify type to assert that error was already reported in `Err` case.

compiler/rustc_hir_pretty/Cargo.toml

@@ -5,9 +5,9 @@ edition = "2021"
 
 [dependencies]
 # tidy-alphabetical-start
+rustc_abi = { path = "../rustc_abi" }
 rustc_ast = { path = "../rustc_ast" }
 rustc_ast_pretty = { path = "../rustc_ast_pretty" }
 rustc_hir = { path = "../rustc_hir" }
 rustc_span = { path = "../rustc_span" }
-rustc_target = { path = "../rustc_target" }
 # tidy-alphabetical-end

compiler/rustc_hir_pretty/src/lib.rs

@@ -9,6 +9,7 @@
 use std::cell::Cell;
 use std::vec;
 
+use rustc_abi::ExternAbi;
 use rustc_ast::util::parser::{self, AssocOp, Fixity};
 use rustc_ast_pretty::pp::Breaks::{Consistent, Inconsistent};
 use rustc_ast_pretty::pp::{self, Breaks};
@@ -20,7 +21,6 @@ use rustc_hir::{
 use rustc_span::FileName;
 use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::{Ident, Symbol, kw};
-use rustc_target::spec::abi::Abi;
 use {rustc_ast as ast, rustc_hir as hir};
 
 pub fn id_to_string(map: &dyn rustc_hir::intravisit::Map<'_>, hir_id: HirId) -> String {
@@ -2240,7 +2240,7 @@ impl<'a> State<'a> {
 
     fn print_ty_fn(
         &mut self,
-        abi: Abi,
+        abi: ExternAbi,
         safety: hir::Safety,
         decl: &hir::FnDecl<'_>,
         name: Option<Symbol>,
@@ -2276,7 +2276,7 @@ impl<'a> State<'a> {
 
         self.print_safety(header.safety);
 
-        if header.abi != Abi::Rust {
+        if header.abi != ExternAbi::Rust {
             self.word_nbsp("extern");
             self.word_nbsp(header.abi.to_string());
         }

compiler/rustc_lint/messages.ftl

@@ -268,7 +268,7 @@ lint_extern_crate_not_idiomatic = `extern crate` is not idiomatic in the new edi
 
 lint_extern_without_abi = extern declarations without an explicit ABI are deprecated
     .label = ABI should be specified here
-    .help = the default ABI is {$default_abi}
+    .suggestion = explicitly specify the {$default_abi} ABI
 
 lint_for_loops_over_fallibles =
     for loop over {$article} `{$ref_prefix}{$ty}`. This is more readably written as an `if let` statement

compiler/rustc_lint/src/lints.rs

@@ -2738,11 +2738,9 @@ pub(crate) struct PatternsInFnsWithoutBodySub {
 
 #[derive(LintDiagnostic)]
 #[diag(lint_extern_without_abi)]
-#[help]
 pub(crate) struct MissingAbi {
-    #[label]
+    #[suggestion(code = "extern \"{default_abi}\"", applicability = "machine-applicable")]
     pub span: Span,
-
     pub default_abi: &'static str,
 }
 

compiler/rustc_lint_defs/Cargo.toml

@@ -5,13 +5,13 @@ edition = "2021"
 
 [dependencies]
 # tidy-alphabetical-start
+rustc_abi = { path = "../rustc_abi" }
 rustc_ast = { path = "../rustc_ast" }
 rustc_data_structures = { path = "../rustc_data_structures" }
 rustc_error_messages = { path = "../rustc_error_messages" }
 rustc_hir = { path = "../rustc_hir" }
 rustc_macros = { path = "../rustc_macros" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_span = { path = "../rustc_span" }
-rustc_target = { path = "../rustc_target" }
 serde = { version = "1.0.125", features = ["derive"] }
 # tidy-alphabetical-end

compiler/rustc_lint_defs/src/lib.rs

@@ -2,6 +2,7 @@
 #![warn(unreachable_pub)]
 // tidy-alphabetical-end
 
+use rustc_abi::ExternAbi;
 use rustc_ast::node_id::NodeId;
 use rustc_ast::{AttrId, Attribute};
 use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
@@ -15,7 +16,6 @@ use rustc_macros::{Decodable, Encodable, HashStable_Generic};
 pub use rustc_span::edition::Edition;
 use rustc_span::symbol::{Ident, MacroRulesNormalizedIdent};
 use rustc_span::{Span, Symbol, sym};
-use rustc_target::spec::abi::Abi;
 use serde::{Deserialize, Serialize};
 
 pub use self::Level::*;
@@ -602,7 +602,7 @@ pub enum BuiltinLintDiag {
         path: String,
         since_kind: DeprecatedSinceKind,
     },
-    MissingAbi(Span, Abi),
+    MissingAbi(Span, ExternAbi),
     UnusedDocComment(Span),
     UnusedBuiltinAttribute {
         attr_name: Symbol,