Rollup of 8 pull requests

compiler/rustc_ast/src/ast.rs

@@ -3184,38 +3184,6 @@ pub struct StaticItem {
     pub expr: Option<P<Expr>>,
 }
 
-/// A static item in `extern` block.
-// This struct is identical to StaticItem for now but it's going to have a safety attribute.
-#[derive(Clone, Encodable, Decodable, Debug)]
-pub struct StaticForeignItem {
-    pub ty: P<Ty>,
-    pub safety: Safety,
-    pub mutability: Mutability,
-    pub expr: Option<P<Expr>>,
-}
-
-impl From<StaticItem> for StaticForeignItem {
-    fn from(static_item: StaticItem) -> StaticForeignItem {
-        StaticForeignItem {
-            ty: static_item.ty,
-            safety: static_item.safety,
-            mutability: static_item.mutability,
-            expr: static_item.expr,
-        }
-    }
-}
-
-impl From<StaticForeignItem> for StaticItem {
-    fn from(static_item: StaticForeignItem) -> StaticItem {
-        StaticItem {
-            ty: static_item.ty,
-            safety: static_item.safety,
-            mutability: static_item.mutability,
-            expr: static_item.expr,
-        }
-    }
-}
-
 #[derive(Clone, Encodable, Decodable, Debug)]
 pub struct ConstItem {
     pub defaultness: Defaultness,
@@ -3430,7 +3398,7 @@ impl TryFrom<ItemKind> for AssocItemKind {
 #[derive(Clone, Encodable, Decodable, Debug)]
 pub enum ForeignItemKind {
     /// A foreign static item (`static FOO: u8`).
-    Static(Box<StaticForeignItem>),
+    Static(Box<StaticItem>),
     /// An foreign function.
     Fn(Box<Fn>),
     /// An foreign type.

compiler/rustc_ast/src/mut_visit.rs

@@ -1310,12 +1310,7 @@ pub fn noop_flat_map_item<K: NoopVisitItemKind>(
 impl NoopVisitItemKind for ForeignItemKind {
     fn noop_visit(&mut self, visitor: &mut impl MutVisitor) {
         match self {
-            ForeignItemKind::Static(box StaticForeignItem {
-                ty,
-                mutability: _,
-                expr,
-                safety: _,
-            }) => {
+            ForeignItemKind::Static(box StaticItem { ty, mutability: _, expr, safety: _ }) => {
                 visitor.visit_ty(ty);
                 visit_opt(expr, |expr| visitor.visit_expr(expr));
             }

compiler/rustc_ast/src/token.rs

@@ -900,7 +900,11 @@ pub enum NonterminalKind {
     PatWithOr,
     Expr,
     /// Matches an expression using the rules from edition 2021 and earlier.
-    Expr2021,
+    Expr2021 {
+        /// Keep track of whether the user used `:expr` or `:expr_2021` and we inferred it from the
+        /// edition of the span. This is used for diagnostics AND feature gating.
+        inferred: bool,
+    },
     Ty,
     Ident,
     Lifetime,
@@ -929,8 +933,13 @@ impl NonterminalKind {
                 Edition::Edition2021 | Edition::Edition2024 => NonterminalKind::PatWithOr,
             },
             sym::pat_param => NonterminalKind::PatParam { inferred: false },
-            sym::expr => NonterminalKind::Expr,
-            sym::expr_2021 if edition().at_least_rust_2021() => NonterminalKind::Expr2021,
+            sym::expr => match edition() {
+                Edition::Edition2015 | Edition::Edition2018 | Edition::Edition2021 => {
+                    NonterminalKind::Expr2021 { inferred: true }
+                }
+                Edition::Edition2024 => NonterminalKind::Expr,
+            },
+            sym::expr_2021 => NonterminalKind::Expr2021 { inferred: false },
             sym::ty => NonterminalKind::Ty,
             sym::ident => NonterminalKind::Ident,
             sym::lifetime => NonterminalKind::Lifetime,
@@ -949,8 +958,8 @@ impl NonterminalKind {
             NonterminalKind::Stmt => sym::stmt,
             NonterminalKind::PatParam { inferred: false } => sym::pat_param,
             NonterminalKind::PatParam { inferred: true } | NonterminalKind::PatWithOr => sym::pat,
-            NonterminalKind::Expr => sym::expr,
-            NonterminalKind::Expr2021 => sym::expr_2021,
+            NonterminalKind::Expr | NonterminalKind::Expr2021 { inferred: true } => sym::expr,
+            NonterminalKind::Expr2021 { inferred: false } => sym::expr_2021,
             NonterminalKind::Ty => sym::ty,
             NonterminalKind::Ident => sym::ident,
             NonterminalKind::Lifetime => sym::lifetime,

compiler/rustc_ast/src/visit.rs

@@ -672,12 +672,7 @@ impl WalkItemKind for ForeignItemKind {
     ) -> V::Result {
         let &Item { id, span, ident, ref vis, .. } = item;
         match self {
-            ForeignItemKind::Static(box StaticForeignItem {
-                ty,
-                mutability: _,
-                expr,
-                safety: _,
-            }) => {
+            ForeignItemKind::Static(box StaticItem { ty, mutability: _, expr, safety: _ }) => {
                 try_visit!(visitor.visit_ty(ty));
                 visit_opt!(visitor, visit_expr, expr);
             }

compiler/rustc_ast_lowering/src/item.rs

@@ -664,12 +664,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
 
                     hir::ForeignItemKind::Fn(fn_dec, fn_args, generics, safety)
                 }
-                ForeignItemKind::Static(box StaticForeignItem {
-                    ty,
-                    mutability,
-                    expr: _,
-                    safety,
-                }) => {
+                ForeignItemKind::Static(box StaticItem { ty, mutability, expr: _, safety }) => {
                     let ty = self
                         .lower_ty(ty, ImplTraitContext::Disallowed(ImplTraitPosition::StaticTy));
                     let safety = self.lower_safety(*safety, hir::Safety::Unsafe);

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -1232,7 +1232,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                 self.check_foreign_ty_genericless(generics, where_clauses);
                 self.check_foreign_item_ascii_only(fi.ident);
             }
-            ForeignItemKind::Static(box StaticForeignItem { expr, safety, .. }) => {
+            ForeignItemKind::Static(box StaticItem { expr, safety, .. }) => {
                 self.check_foreign_item_safety(fi.span, *safety);
                 self.check_foreign_kind_bodyless(fi.ident, "static", expr.as_ref().map(|b| b.span));
                 self.check_foreign_item_ascii_only(fi.ident);

compiler/rustc_ast_pretty/src/pprust/state/item.rs

@@ -37,12 +37,7 @@ impl<'a> State<'a> {
             ast::ForeignItemKind::Fn(box ast::Fn { defaultness, sig, generics, body }) => {
                 self.print_fn_full(sig, ident, generics, vis, *defaultness, body.as_deref(), attrs);
             }
-            ast::ForeignItemKind::Static(box ast::StaticForeignItem {
-                ty,
-                mutability,
-                expr,
-                safety,
-            }) => {
+            ast::ForeignItemKind::Static(box ast::StaticItem { ty, mutability, expr, safety }) => {
                 self.print_safety(*safety);
                 self.print_item_const(
                     ident,

compiler/rustc_errors/src/lib.rs

@@ -1456,10 +1456,10 @@ impl DiagCtxtInner {
         }
 
         if diagnostic.has_future_breakage() {
-            // Future breakages aren't emitted if they're `Level::Allow`,
-            // but they still need to be constructed and stashed below,
-            // so they'll trigger the must_produce_diag check.
-            assert!(matches!(diagnostic.level, Error | Warning | Allow));
+            // Future breakages aren't emitted if they're `Level::Allow` or
+            // `Level::Expect`, but they still need to be constructed and
+            // stashed below, so they'll trigger the must_produce_diag check.
+            assert!(matches!(diagnostic.level, Error | Warning | Allow | Expect(_)));
             self.future_breakage_diagnostics.push(diagnostic.clone());
         }
 

compiler/rustc_expand/src/mbe/macro_rules.rs

@@ -1292,7 +1292,9 @@ fn is_in_follow(tok: &mbe::TokenTree, kind: NonterminalKind) -> IsInFollow {
                 // maintain
                 IsInFollow::Yes
             }
-            NonterminalKind::Stmt | NonterminalKind::Expr | NonterminalKind::Expr2021 => {
+            NonterminalKind::Stmt
+            | NonterminalKind::Expr
+            | NonterminalKind::Expr2021 { inferred: _ } => {
                 const TOKENS: &[&str] = &["`=>`", "`,`", "`;`"];
                 match tok {
                     TokenTree::Token(token) => match token.kind {

compiler/rustc_expand/src/mbe/quoted.rs

@@ -113,7 +113,8 @@ pub(super) fn parse(
                                                 );
                                                 token::NonterminalKind::Ident
                                             });
-                                    if kind == token::NonterminalKind::Expr2021
+                                    if kind
+                                        == (token::NonterminalKind::Expr2021 { inferred: false })
                                         && !features.expr_fragment_specifier_2024
                                     {
                                         rustc_session::parse::feature_err(

compiler/rustc_parse/src/parser/diagnostics.rs

@@ -2965,9 +2965,10 @@ impl<'a> Parser<'a> {
 
     /// This checks if this is a conflict marker, depending of the parameter passed.
     ///
-    /// * `>>>>>`
-    /// * `=====`
-    /// * `<<<<<`
+    /// * `<<<<<<<`
+    /// * `|||||||`
+    /// * `=======`
+    /// * `>>>>>>>`
     ///
     pub(super) fn is_vcs_conflict_marker(
         &mut self,
@@ -2997,14 +2998,18 @@ impl<'a> Parser<'a> {
     }
 
     pub(crate) fn err_vcs_conflict_marker(&mut self) -> PResult<'a, ()> {
+        // <<<<<<<
         let Some(start) = self.conflict_marker(&TokenKind::BinOp(token::Shl), &TokenKind::Lt)
         else {
             return Ok(());
         };
         let mut spans = Vec::with_capacity(3);
         spans.push(start);
+        // |||||||
         let mut middlediff3 = None;
+        // =======
         let mut middle = None;
+        // >>>>>>>
         let mut end = None;
         loop {
             if self.token.kind == TokenKind::Eof {
@@ -3025,29 +3030,50 @@ impl<'a> Parser<'a> {
             }
             self.bump();
         }
+
         let mut err = self.dcx().struct_span_err(spans, "encountered diff marker");
-        err.span_label(start, "after this is the code before the merge");
-        if let Some(middle) = middlediff3 {
-            err.span_label(middle, "");
-        }
+        match middlediff3 {
+            // We're using diff3
+            Some(middlediff3) => {
+                err.span_label(
+                    start,
+                    "between this marker and `|||||||` is the code that we're merging into",
+                );
+                err.span_label(middlediff3, "between this marker and `=======` is the base code (what the two refs diverged from)");
+            }
+            None => {
+                err.span_label(
+                    start,
+                    "between this marker and `=======` is the code that we're merging into",
+                );
+            }
+        };
+
         if let Some(middle) = middle {
-            err.span_label(middle, "");
+            err.span_label(middle, "between this marker and `>>>>>>>` is the incoming code");
         }
         if let Some(end) = end {
-            err.span_label(end, "above this are the incoming code changes");
+            err.span_label(end, "this marker concludes the conflict region");
         }
-        err.help(
-            "if you're having merge conflicts after pulling new code, the top section is the code \
-             you already had and the bottom section is the remote code",
+        err.note(
+            "conflict markers indicate that a merge was started but could not be completed due \
+             to merge conflicts\n\
+             to resolve a conflict, keep only the code you want and then delete the lines \
+             containing conflict markers",
         );
         err.help(
-            "if you're in the middle of a rebase, the top section is the code being rebased onto \
-             and the bottom section is the code coming from the current commit being rebased",
+            "if you're having merge conflicts after pulling new code:\n\
+             the top section is the code you already had and the bottom section is the remote code\n\
+             if you're in the middle of a rebase:\n\
+             the top section is the code being rebased onto and the bottom section is the code \
+             coming from the current commit being rebased",
         );
+
         err.note(
-            "for an explanation on these markers from the `git` documentation, visit \
-             <https://git-scm.com/book/en/v2/Git-Tools-Advanced-Merging#_checking_out_conflicts>",
+            "for an explanation on these markers from the `git` documentation:\n\
+             visit <https://git-scm.com/book/en/v2/Git-Tools-Advanced-Merging#_checking_out_conflicts>",
         );
+
         Err(err)
     }
 

compiler/rustc_parse/src/parser/item.rs

@@ -1228,7 +1228,7 @@ impl<'a> Parser<'a> {
                                 ident_span: ident.span,
                                 const_span,
                             });
-                            ForeignItemKind::Static(Box::new(StaticForeignItem {
+                            ForeignItemKind::Static(Box::new(StaticItem {
                                 ty,
                                 mutability: Mutability::Not,
                                 expr,

compiler/rustc_parse/src/parser/nonterminal.rs

@@ -36,7 +36,7 @@ impl<'a> Parser<'a> {
         }
 
         match kind {
-            NonterminalKind::Expr2021 => {
+            NonterminalKind::Expr2021 { inferred: _ } => {
                 token.can_begin_expr()
                 // This exception is here for backwards compatibility.
                 && !token.is_keyword(kw::Let)
@@ -47,7 +47,6 @@ impl<'a> Parser<'a> {
                 token.can_begin_expr()
                 // This exception is here for backwards compatibility.
                 && !token.is_keyword(kw::Let)
-                && (!token.is_keyword(kw::Const) || token.span.edition().at_least_rust_2024())
             }
             NonterminalKind::Ty => token.can_begin_type(),
             NonterminalKind::Ident => get_macro_ident(token).is_some(),
@@ -149,7 +148,7 @@ impl<'a> Parser<'a> {
                 })?)
             }
 
-            NonterminalKind::Expr | NonterminalKind::Expr2021 => {
+            NonterminalKind::Expr | NonterminalKind::Expr2021 { inferred: _ } => {
                 NtExpr(self.parse_expr_force_collect()?)
             }
             NonterminalKind::Literal => {

compiler/rustc_resolve/src/def_collector.rs

@@ -217,12 +217,7 @@ impl<'a, 'b, 'tcx> visit::Visitor<'a> for DefCollector<'a, 'b, 'tcx> {
 
     fn visit_foreign_item(&mut self, fi: &'a ForeignItem) {
         let def_kind = match fi.kind {
-            ForeignItemKind::Static(box StaticForeignItem {
-                ty: _,
-                mutability,
-                expr: _,
-                safety,
-            }) => {
+            ForeignItemKind::Static(box StaticItem { ty: _, mutability, expr: _, safety }) => {
                 let safety = match safety {
                     ast::Safety::Unsafe(_) | ast::Safety::Default => hir::Safety::Unsafe,
                     ast::Safety::Safe(_) => hir::Safety::Safe,

compiler/rustc_target/src/target_features.rs

@@ -208,6 +208,11 @@ const X86_ALLOWED_FEATURES: &[(&str, Stability)] = &[
     ("avx512vnni", Unstable(sym::avx512_target_feature)),
     ("avx512vp2intersect", Unstable(sym::avx512_target_feature)),
     ("avx512vpopcntdq", Unstable(sym::avx512_target_feature)),
+    ("avxifma", Unstable(sym::avx512_target_feature)),
+    ("avxneconvert", Unstable(sym::avx512_target_feature)),
+    ("avxvnni", Unstable(sym::avx512_target_feature)),
+    ("avxvnniint16", Unstable(sym::avx512_target_feature)),
+    ("avxvnniint8", Unstable(sym::avx512_target_feature)),
     ("bmi1", Stable),
     ("bmi2", Stable),
     ("cmpxchg16b", Stable),