Rollup of 3 pull requests

compiler/rustc_attr_parsing/messages.ftl

@@ -1,5 +1,5 @@
 attr_parsing_as_needed_compatibility =
-    linking modifier `as-needed` is only compatible with `dylib` and `framework` linking kinds
+    linking modifier `as-needed` is only compatible with `dylib`, `framework` and `raw-dylib` linking kinds
 
 attr_parsing_bundle_needs_static =
     linking modifier `bundle` is only compatible with `static` linking kind

compiler/rustc_attr_parsing/src/attributes/link_attrs.rs

@@ -180,7 +180,8 @@ impl<S: Stage> CombineAttributeParser<S> for LinkParser {
                     }
 
                     (sym::as_dash_needed, Some(NativeLibKind::Dylib { as_needed }))
-                    | (sym::as_dash_needed, Some(NativeLibKind::Framework { as_needed })) => {
+                    | (sym::as_dash_needed, Some(NativeLibKind::Framework { as_needed }))
+                    | (sym::as_dash_needed, Some(NativeLibKind::RawDylib { as_needed })) => {
                         report_unstable_modifier!(native_link_modifiers_as_needed);
                         assign_modifier(as_needed)
                     }
@@ -219,12 +220,12 @@ impl<S: Stage> CombineAttributeParser<S> for LinkParser {
 
         // Do this outside of the loop so that `import_name_type` can be specified before `kind`.
         if let Some((_, span)) = import_name_type {
-            if kind != Some(NativeLibKind::RawDylib) {
+            if !matches!(kind, Some(NativeLibKind::RawDylib { .. })) {
                 cx.emit_err(ImportNameTypeRaw { span });
             }
         }
 
-        if let Some(NativeLibKind::RawDylib) = kind
+        if let Some(NativeLibKind::RawDylib { .. }) = kind
             && name.as_str().contains('\0')
         {
             cx.emit_err(RawDylibNoNul { span: name_span });
@@ -315,7 +316,7 @@ impl LinkParser {
                     cx.emit_err(RawDylibOnlyWindows { span: nv.value_span });
                 }
 
-                NativeLibKind::RawDylib
+                NativeLibKind::RawDylib { as_needed: None }
             }
             sym::link_dash_arg => {
                 if !features.link_arg_attribute() {

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -1490,7 +1490,7 @@ fn print_native_static_libs(
                 NativeLibKind::Static { bundle: None | Some(true), .. }
                 | NativeLibKind::LinkArg
                 | NativeLibKind::WasmImportModule
-                | NativeLibKind::RawDylib => None,
+                | NativeLibKind::RawDylib { .. } => None,
             }
         })
         // deduplication of consecutive repeated libraries, see rust-lang/rust#113209
@@ -2364,13 +2364,13 @@ fn linker_with_args(
             cmd.add_object(&output_path);
         }
     } else {
-        for link_path in raw_dylib::create_raw_dylib_elf_stub_shared_objects(
+        for (link_path, as_needed) in raw_dylib::create_raw_dylib_elf_stub_shared_objects(
             sess,
             codegen_results.crate_info.used_libraries.iter(),
             &raw_dylib_dir,
         ) {
             // Always use verbatim linkage, see comments in create_raw_dylib_elf_stub_shared_objects.
-            cmd.link_dylib_by_name(&link_path, true, false);
+            cmd.link_dylib_by_name(&link_path, true, as_needed);
         }
     }
     // As with add_upstream_native_libraries, we need to add the upstream raw-dylib symbols in case
@@ -2411,13 +2411,13 @@ fn linker_with_args(
             cmd.add_object(&output_path);
         }
     } else {
-        for link_path in raw_dylib::create_raw_dylib_elf_stub_shared_objects(
+        for (link_path, as_needed) in raw_dylib::create_raw_dylib_elf_stub_shared_objects(
             sess,
             native_libraries_from_nonstatics,
             &raw_dylib_dir,
         ) {
             // Always use verbatim linkage, see comments in create_raw_dylib_elf_stub_shared_objects.
-            cmd.link_dylib_by_name(&link_path, true, false);
+            cmd.link_dylib_by_name(&link_path, true, as_needed);
         }
     }
 
@@ -2726,7 +2726,7 @@ fn add_native_libs_from_crate(
                     cmd.link_framework_by_name(name, verbatim, as_needed.unwrap_or(true))
                 }
             }
-            NativeLibKind::RawDylib => {
+            NativeLibKind::RawDylib { as_needed: _ } => {
                 // Handled separately in `linker_with_args`.
             }
             NativeLibKind::WasmImportModule => {}

compiler/rustc_codegen_ssa/src/back/link/raw_dylib.rs

@@ -31,7 +31,7 @@ fn collate_raw_dylibs_windows<'a>(
     let mut dylib_table = FxIndexMap::<String, FxIndexMap<Symbol, &DllImport>>::default();
 
     for lib in used_libraries {
-        if lib.kind == NativeLibKind::RawDylib {
+        if let NativeLibKind::RawDylib { .. } = lib.kind {
             let ext = if lib.verbatim { "" } else { ".dll" };
             let name = format!("{}{}", lib.name, ext);
             let imports = dylib_table.entry(name.clone()).or_default();
@@ -128,12 +128,12 @@ pub(super) fn create_raw_dylib_dll_import_libs<'a>(
 fn collate_raw_dylibs_elf<'a>(
     sess: &Session,
     used_libraries: impl IntoIterator<Item = &'a NativeLib>,
-) -> Vec<(String, Vec<DllImport>)> {
+) -> Vec<(String, Vec<DllImport>, bool)> {
     // Use index maps to preserve original order of imports and libraries.
-    let mut dylib_table = FxIndexMap::<String, FxIndexMap<Symbol, &DllImport>>::default();
+    let mut dylib_table = FxIndexMap::<String, (FxIndexMap<Symbol, &DllImport>, bool)>::default();
 
     for lib in used_libraries {
-        if lib.kind == NativeLibKind::RawDylib {
+        if let NativeLibKind::RawDylib { as_needed } = lib.kind {
             let filename = if lib.verbatim {
                 lib.name.as_str().to_owned()
             } else {
@@ -142,17 +142,19 @@ fn collate_raw_dylibs_elf<'a>(
                 format!("{prefix}{}{ext}", lib.name)
             };
 
-            let imports = dylib_table.entry(filename.clone()).or_default();
+            let (stub_imports, stub_as_needed) =
+                dylib_table.entry(filename.clone()).or_insert((Default::default(), true));
             for import in &lib.dll_imports {
-                imports.insert(import.name, import);
+                stub_imports.insert(import.name, import);
             }
+            *stub_as_needed = *stub_as_needed && as_needed.unwrap_or(true);
         }
     }
     sess.dcx().abort_if_errors();
     dylib_table
         .into_iter()
-        .map(|(name, imports)| {
-            (name, imports.into_iter().map(|(_, import)| import.clone()).collect())
+        .map(|(name, (imports, as_needed))| {
+            (name, imports.into_iter().map(|(_, import)| import.clone()).collect(), as_needed)
         })
         .collect()
 }
@@ -161,10 +163,10 @@ pub(super) fn create_raw_dylib_elf_stub_shared_objects<'a>(
     sess: &Session,
     used_libraries: impl IntoIterator<Item = &'a NativeLib>,
     raw_dylib_so_dir: &Path,
-) -> Vec<String> {
+) -> Vec<(String, bool)> {
     collate_raw_dylibs_elf(sess, used_libraries)
         .into_iter()
-        .map(|(load_filename, raw_dylib_imports)| {
+        .map(|(load_filename, raw_dylib_imports, as_needed)| {
             use std::hash::Hash;
 
             // `load_filename` is the *target/loader* filename that will end up in NEEDED.
@@ -205,7 +207,7 @@ pub(super) fn create_raw_dylib_elf_stub_shared_objects<'a>(
                 });
             };
 
-            temporary_lib_name
+            (temporary_lib_name, as_needed)
         })
         .collect()
 }

compiler/rustc_hir/src/attrs/data_structures.rs

@@ -309,7 +309,10 @@ pub enum NativeLibKind {
     },
     /// Dynamic library (e.g. `foo.dll` on Windows) without a corresponding import library.
     /// On Linux, it refers to a generated shared library stub.
-    RawDylib,
+    RawDylib {
+        /// Whether the dynamic library will be linked only if it satisfies some undefined symbols
+        as_needed: Option<bool>,
+    },
     /// A macOS-specific kind of dynamic libraries.
     Framework {
         /// Whether the framework will be linked only if it satisfies some undefined symbols
@@ -332,11 +335,10 @@ impl NativeLibKind {
             NativeLibKind::Static { bundle, whole_archive } => {
                 bundle.is_some() || whole_archive.is_some()
             }
-            NativeLibKind::Dylib { as_needed } | NativeLibKind::Framework { as_needed } => {
-                as_needed.is_some()
-            }
-            NativeLibKind::RawDylib
-            | NativeLibKind::Unspecified
+            NativeLibKind::Dylib { as_needed }
+            | NativeLibKind::Framework { as_needed }
+            | NativeLibKind::RawDylib { as_needed } => as_needed.is_some(),
+            NativeLibKind::Unspecified
             | NativeLibKind::LinkArg
             | NativeLibKind::WasmImportModule => false,
         }
@@ -349,7 +351,9 @@ impl NativeLibKind {
     pub fn is_dllimport(&self) -> bool {
         matches!(
             self,
-            NativeLibKind::Dylib { .. } | NativeLibKind::RawDylib | NativeLibKind::Unspecified
+            NativeLibKind::Dylib { .. }
+                | NativeLibKind::RawDylib { .. }
+                | NativeLibKind::Unspecified
         )
     }
 }

compiler/rustc_metadata/src/native_libs.rs

@@ -218,7 +218,7 @@ impl<'tcx> Collector<'tcx> {
                 .flatten()
         {
             let dll_imports = match attr.kind {
-                NativeLibKind::RawDylib => foreign_items
+                NativeLibKind::RawDylib { .. } => foreign_items
                     .iter()
                     .map(|&child_item| {
                         self.build_dll_import(

compiler/rustc_session/src/config/native_libs.rs

@@ -135,7 +135,8 @@ fn parse_and_apply_modifier(cx: &ParseNativeLibCx<'_>, modifier: &str, native_li
         ),
 
         ("as-needed", NativeLibKind::Dylib { as_needed })
-        | ("as-needed", NativeLibKind::Framework { as_needed }) => {
+        | ("as-needed", NativeLibKind::Framework { as_needed })
+        | ("as-needed", NativeLibKind::RawDylib { as_needed }) => {
             cx.on_unstable_value(
                 "linking modifier `as-needed` is unstable",
                 ", the `-Z unstable-options` flag must also be passed to use it",

compiler/rustc_trait_selection/src/error_reporting/traits/fulfillment_errors.rs

@@ -467,7 +467,8 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
                             span,
                             leaf_trait_predicate,
                         );
-                        self.note_version_mismatch(&mut err, leaf_trait_predicate);
+                        self.note_trait_version_mismatch(&mut err, leaf_trait_predicate);
+                        self.note_adt_version_mismatch(&mut err, leaf_trait_predicate);
                         self.suggest_remove_await(&obligation, &mut err);
                         self.suggest_derive(&obligation, &mut err, leaf_trait_predicate);
 
@@ -2424,7 +2425,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
     /// If the `Self` type of the unsatisfied trait `trait_ref` implements a trait
     /// with the same path as `trait_ref`, a help message about
     /// a probable version mismatch is added to `err`
-    fn note_version_mismatch(
+    fn note_trait_version_mismatch(
         &self,
         err: &mut Diag<'_>,
         trait_pred: ty::PolyTraitPredicate<'tcx>,
@@ -2464,15 +2465,87 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
                 impl_spans,
                 format!("trait impl{} with same name found", pluralize!(trait_impls.len())),
             );
-            let trait_crate = self.tcx.crate_name(trait_with_same_path.krate);
-            let crate_msg =
-                format!("perhaps two different versions of crate `{trait_crate}` are being used?");
-            err.note(crate_msg);
+            self.note_two_crate_versions(trait_with_same_path, err);
             suggested = true;
         }
         suggested
     }
 
+    fn note_two_crate_versions(&self, did: DefId, err: &mut Diag<'_>) {
+        let crate_name = self.tcx.crate_name(did.krate);
+        let crate_msg =
+            format!("perhaps two different versions of crate `{crate_name}` are being used?");
+        err.note(crate_msg);
+    }
+
+    fn note_adt_version_mismatch(
+        &self,
+        err: &mut Diag<'_>,
+        trait_pred: ty::PolyTraitPredicate<'tcx>,
+    ) {
+        let ty::Adt(impl_self_def, _) = trait_pred.self_ty().skip_binder().peel_refs().kind()
+        else {
+            return;
+        };
+
+        let impl_self_did = impl_self_def.did();
+
+        // We only want to warn about different versions of a dependency.
+        // If no dependency is involved, bail.
+        if impl_self_did.krate == LOCAL_CRATE {
+            return;
+        }
+
+        let impl_self_path = self.comparable_path(impl_self_did);
+        let impl_self_crate_name = self.tcx.crate_name(impl_self_did.krate);
+        let similar_items: UnordSet<_> = self
+            .tcx
+            .visible_parent_map(())
+            .items()
+            .filter_map(|(&item, _)| {
+                // If we found ourselves, ignore.
+                if impl_self_did == item {
+                    return None;
+                }
+                // We only want to warn about different versions of a dependency.
+                // Ignore items from our own crate.
+                if item.krate == LOCAL_CRATE {
+                    return None;
+                }
+                // We want to warn about different versions of a dependency.
+                // So make sure the crate names are the same.
+                if impl_self_crate_name != self.tcx.crate_name(item.krate) {
+                    return None;
+                }
+                // Filter out e.g. constructors that often have the same path
+                // str as the relevant ADT.
+                if !self.tcx.def_kind(item).is_adt() {
+                    return None;
+                }
+                let path = self.comparable_path(item);
+                // We don't know if our item or the one we found is the re-exported one.
+                // Check both cases.
+                let is_similar = path.ends_with(&impl_self_path) || impl_self_path.ends_with(&path);
+                is_similar.then_some((item, path))
+            })
+            .collect();
+
+        let mut similar_items =
+            similar_items.into_items().into_sorted_stable_ord_by_key(|(_, path)| path);
+        similar_items.dedup();
+
+        for (similar_item, _) in similar_items {
+            err.span_help(self.tcx.def_span(similar_item), "item with same name found");
+            self.note_two_crate_versions(similar_item, err);
+        }
+    }
+
+    /// Add a `::` prefix when comparing paths so that paths with just one item
+    /// like "Foo" does not equal the end of "OtherFoo".
+    fn comparable_path(&self, did: DefId) -> String {
+        format!("::{}", self.tcx.def_path_str(did))
+    }
+
     /// Creates a `PredicateObligation` with `new_self_ty` replacing the existing type in the
     /// `trait_ref`.
     ///

src/librustdoc/html/highlight.rs

@@ -8,7 +8,7 @@
 use std::borrow::Cow;
 use std::collections::VecDeque;
 use std::fmt::{self, Display, Write};
-use std::iter;
+use std::{cmp, iter};
 
 use rustc_data_structures::fx::FxIndexMap;
 use rustc_lexer::{Cursor, FrontmatterAllowed, LiteralKind, TokenKind};
@@ -345,33 +345,26 @@ fn end_expansion<'a, W: Write>(
         token_handler.pending_elems.push((Cow::Borrowed("</span>"), Some(Class::Expansion)));
         return Some(expanded_code);
     }
-    if expansion_start_tags.is_empty() && token_handler.closing_tags.is_empty() {
-        // No need tag opened so we can just close expansion.
-        token_handler.pending_elems.push((Cow::Borrowed("</span></span>"), Some(Class::Expansion)));
-        return None;
-    }
 
-    // If tags were opened inside the expansion, we need to close them and re-open them outside
-    // of the expansion span.
-    let mut out = String::new();
-    let mut end = String::new();
+    let skip = iter::zip(token_handler.closing_tags.as_slice(), expansion_start_tags)
+        .position(|(tag, start_tag)| tag != start_tag)
+        .unwrap_or_else(|| cmp::min(token_handler.closing_tags.len(), expansion_start_tags.len()));
 
-    let mut closing_tags = token_handler.closing_tags.iter().peekable();
-    let mut start_closing_tags = expansion_start_tags.iter().peekable();
+    let tags = iter::chain(
+        expansion_start_tags.iter().skip(skip),
+        token_handler.closing_tags.iter().skip(skip),
+    );
 
-    while let (Some(tag), Some(start_tag)) = (closing_tags.peek(), start_closing_tags.peek())
-        && tag == start_tag
-    {
-        closing_tags.next();
-        start_closing_tags.next();
+    let mut elem = Cow::Borrowed("</span></span>");
+
+    for (tag, _) in tags.clone() {
+        elem.to_mut().push_str(tag);
     }
-    for (tag, class) in start_closing_tags.chain(closing_tags) {
-        out.push_str(tag);
-        end.push_str(&format!("<span class=\"{}\">", class.as_html()));
+    for (_, class) in tags {
+        write!(elem.to_mut(), "<span class=\"{}\">", class.as_html()).unwrap();
     }
-    token_handler
-        .pending_elems
-        .push((Cow::Owned(format!("</span></span>{out}{end}")), Some(Class::Expansion)));
+
+    token_handler.pending_elems.push((elem, Some(Class::Expansion)));
     None
 }
 

tests/run-make/duplicate-dependency/foo-v1.rs

@@ -0,0 +1 @@
+pub struct Foo;

tests/run-make/duplicate-dependency/foo-v2.rs

@@ -0,0 +1 @@
+pub struct Foo;