Auto merge of #143305 - jhpratt:rollup-t7e7uhj, r=jhpratt

Rollup of 12 pull requests

Successful merges:

 - #141829 (Specialize sleep_until implementation for unix (except mac))
 - #141847 (Explain `TOCTOU` on the top of `std::fs`, and reference it in functions)
 - #142138 (Add `Vec::into_chunks`)
 - #142321 (Expose elf abi on ppc64 targets)
 - #142568 (Use the .drectve section for exporting symbols from dlls on Windows)
 - #142886 (ci: aarch64-gnu: Stop skipping `panic_abort_doc_tests`)
 - #143038 (avoid suggesting traits from private dependencies)
 - #143194 (fix bitcast of single-element SIMD vectors)
 - #143206 (Align attr fixes)
 - #143258 (Don't recompute `DisambiguatorState` for every RPITIT in trait definition)
 - #143260 (Use the correct export kind for __rust_alloc_error_handler_should_panic)
 - #143274 (ci: support optional jobs)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -1957,9 +1957,11 @@ fn add_linked_symbol_object(
     cmd: &mut dyn Linker,
     sess: &Session,
     tmpdir: &Path,
-    symbols: &[(String, SymbolExportKind)],
+    crate_type: CrateType,
+    linked_symbols: &[(String, SymbolExportKind)],
+    exported_symbols: &[(String, SymbolExportKind)],
 ) {
-    if symbols.is_empty() {
+    if linked_symbols.is_empty() && exported_symbols.is_empty() {
         return;
     }
 
@@ -1996,7 +1998,7 @@ fn add_linked_symbol_object(
         None
     };
 
-    for (sym, kind) in symbols.iter() {
+    for (sym, kind) in linked_symbols.iter() {
         let symbol = file.add_symbol(object::write::Symbol {
             name: sym.clone().into(),
             value: 0,
@@ -2054,6 +2056,41 @@ fn add_linked_symbol_object(
         }
     }
 
+    if sess.target.is_like_msvc {
+        // Symbol visibility takes care of this for executables typically
+        let should_filter_symbols = if crate_type == CrateType::Executable {
+            sess.opts.unstable_opts.export_executable_symbols
+        } else {
+            true
+        };
+        if should_filter_symbols {
+            // Currently the compiler doesn't use `dllexport` (an LLVM attribute) to
+            // export symbols from a dynamic library. When building a dynamic library,
+            // however, we're going to want some symbols exported, so this adds a
+            // `.drectve` section which lists all the symbols using /EXPORT arguments.
+            //
+            // The linker will read these arguments from the `.drectve` section and
+            // export all the symbols from the dynamic library. Note that this is not
+            // as simple as just exporting all the symbols in the current crate (as
+            // specified by `codegen.reachable`) but rather we also need to possibly
+            // export the symbols of upstream crates. Upstream rlibs may be linked
+            // statically to this dynamic library, in which case they may continue to
+            // transitively be used and hence need their symbols exported.
+            let drectve = exported_symbols
+                .into_iter()
+                .map(|(sym, kind)| match kind {
+                    SymbolExportKind::Text | SymbolExportKind::Tls => format!(" /EXPORT:\"{sym}\""),
+                    SymbolExportKind::Data => format!(" /EXPORT:\"{sym}\",DATA"),
+                })
+                .collect::<Vec<_>>()
+                .join("");
+
+            let section =
+                file.add_section(vec![], b".drectve".to_vec(), object::SectionKind::Linker);
+            file.append_section_data(section, drectve.as_bytes(), 1);
+        }
+    }
+
     let path = tmpdir.join("symbols.o");
     let result = std::fs::write(&path, file.write().unwrap());
     if let Err(error) = result {
@@ -2228,7 +2265,9 @@ fn linker_with_args(
         cmd,
         sess,
         tmpdir,
+        crate_type,
         &codegen_results.crate_info.linked_symbols[&crate_type],
+        &codegen_results.crate_info.exported_symbols[&crate_type],
     );
 
     // Sanitizer libraries.

compiler/rustc_codegen_ssa/src/back/linker.rs

@@ -1097,53 +1097,13 @@ impl<'a> Linker for MsvcLinker<'a> {
         }
     }
 
-    // Currently the compiler doesn't use `dllexport` (an LLVM attribute) to
-    // export symbols from a dynamic library. When building a dynamic library,
-    // however, we're going to want some symbols exported, so this function
-    // generates a DEF file which lists all the symbols.
-    //
-    // The linker will read this `*.def` file and export all the symbols from
-    // the dynamic library. Note that this is not as simple as just exporting
-    // all the symbols in the current crate (as specified by `codegen.reachable`)
-    // but rather we also need to possibly export the symbols of upstream
-    // crates. Upstream rlibs may be linked statically to this dynamic library,
-    // in which case they may continue to transitively be used and hence need
-    // their symbols exported.
     fn export_symbols(
         &mut self,
-        tmpdir: &Path,
-        crate_type: CrateType,
-        symbols: &[(String, SymbolExportKind)],
+        _tmpdir: &Path,
+        _crate_type: CrateType,
+        _symbols: &[(String, SymbolExportKind)],
     ) {
-        // Symbol visibility takes care of this typically
-        if crate_type == CrateType::Executable {
-            let should_export_executable_symbols =
-                self.sess.opts.unstable_opts.export_executable_symbols;
-            if !should_export_executable_symbols {
-                return;
-            }
-        }
-
-        let path = tmpdir.join("lib.def");
-        let res: io::Result<()> = try {
-            let mut f = File::create_buffered(&path)?;
-
-            // Start off with the standard module name header and then go
-            // straight to exports.
-            writeln!(f, "LIBRARY")?;
-            writeln!(f, "EXPORTS")?;
-            for (symbol, kind) in symbols {
-                let kind_marker = if *kind == SymbolExportKind::Data { " DATA" } else { "" };
-                debug!("  _{symbol}");
-                writeln!(f, "  {symbol}{kind_marker}")?;
-            }
-        };
-        if let Err(error) = res {
-            self.sess.dcx().emit_fatal(errors::LibDefWriteFailure { error });
-        }
-        let mut arg = OsString::from("/DEF:");
-        arg.push(path);
-        self.link_arg(&arg);
+        // We already add /EXPORT arguments to the .drectve section of symbols.o.
     }
 
     fn subsystem(&mut self, subsystem: &str) {

compiler/rustc_codegen_ssa/src/back/symbol_export.rs

@@ -219,13 +219,18 @@ fn exported_non_generic_symbols_provider_local<'tcx>(
 
     // Mark allocator shim symbols as exported only if they were generated.
     if allocator_kind_for_codegen(tcx).is_some() {
-        for symbol_name in ALLOCATOR_METHODS
+        for (symbol_name, export_kind) in ALLOCATOR_METHODS
             .iter()
-            .map(|method| mangle_internal_symbol(tcx, global_fn_name(method.name).as_str()))
+            .map(|method| {
+                (
+                    mangle_internal_symbol(tcx, global_fn_name(method.name).as_str()),
+                    SymbolExportKind::Text,
+                )
+            })
             .chain([
-                mangle_internal_symbol(tcx, "__rust_alloc_error_handler"),
-                mangle_internal_symbol(tcx, OomStrategy::SYMBOL),
-                mangle_internal_symbol(tcx, NO_ALLOC_SHIM_IS_UNSTABLE),
+                (mangle_internal_symbol(tcx, "__rust_alloc_error_handler"), SymbolExportKind::Text),
+                (mangle_internal_symbol(tcx, OomStrategy::SYMBOL), SymbolExportKind::Data),
+                (mangle_internal_symbol(tcx, NO_ALLOC_SHIM_IS_UNSTABLE), SymbolExportKind::Text),
             ])
         {
             let exported_symbol = ExportedSymbol::NoDefId(SymbolName::new(tcx, &symbol_name));
@@ -234,7 +239,7 @@ fn exported_non_generic_symbols_provider_local<'tcx>(
                 exported_symbol,
                 SymbolExportInfo {
                     level: SymbolExportLevel::Rust,
-                    kind: SymbolExportKind::Text,
+                    kind: export_kind,
                     used: false,
                     rustc_std_internal_symbol: true,
                 },

compiler/rustc_codegen_ssa/src/codegen_attrs.rs

@@ -4,7 +4,7 @@ use rustc_abi::{Align, ExternAbi};
 use rustc_ast::expand::autodiff_attrs::{AutoDiffAttrs, DiffActivity, DiffMode};
 use rustc_ast::{LitKind, MetaItem, MetaItemInner, attr};
 use rustc_attr_data_structures::{
-    AttributeKind, InlineAttr, InstructionSetAttr, OptimizeAttr, ReprAttr, UsedBy, find_attr,
+    AttributeKind, InlineAttr, InstructionSetAttr, OptimizeAttr, UsedBy, find_attr,
 };
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LOCAL_CRATE, LocalDefId};
@@ -109,14 +109,6 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: LocalDefId) -> CodegenFnAttrs {
 
         if let hir::Attribute::Parsed(p) = attr {
             match p {
-                AttributeKind::Repr(reprs) => {
-                    codegen_fn_attrs.alignment = reprs
-                        .iter()
-                        .filter_map(
-                            |(r, _)| if let ReprAttr::ReprAlign(x) = r { Some(*x) } else { None },
-                        )
-                        .max();
-                }
                 AttributeKind::Cold(_) => codegen_fn_attrs.flags |= CodegenFnAttrFlags::COLD,
                 AttributeKind::ExportName { name, .. } => {
                     codegen_fn_attrs.export_name = Some(*name);

compiler/rustc_codegen_ssa/src/mir/rvalue.rs

@@ -1117,7 +1117,7 @@ pub(super) fn transmute_immediate<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     // While optimizations will remove no-op transmutes, they might still be
     // there in debug or things that aren't no-op in MIR because they change
     // the Rust type but not the underlying layout/niche.
-    if from_scalar == to_scalar {
+    if from_scalar == to_scalar && from_backend_ty == to_backend_ty {
         return imm;
     }
 
@@ -1136,13 +1136,7 @@ pub(super) fn transmute_immediate<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     assume_scalar_range(bx, imm, from_scalar, from_backend_ty);
 
     imm = match (from_scalar.primitive(), to_scalar.primitive()) {
-        (Int(..) | Float(_), Int(..) | Float(_)) => {
-            if from_backend_ty == to_backend_ty {
-                imm
-            } else {
-                bx.bitcast(imm, to_backend_ty)
-            }
-        }
+        (Int(..) | Float(_), Int(..) | Float(_)) => bx.bitcast(imm, to_backend_ty),
         (Pointer(..), Pointer(..)) => bx.pointercast(imm, to_backend_ty),
         (Int(..), Pointer(..)) => bx.ptradd(bx.const_null(bx.type_ptr()), imm),
         (Pointer(..), Int(..)) => {

compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs

@@ -1588,7 +1588,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             &infcx_
         };
 
-        tcx.all_traits()
+        tcx.all_traits_including_private()
             .filter(|trait_def_id| {
                 // Consider only traits with the associated type
                 tcx.associated_items(*trait_def_id)
@@ -2459,13 +2459,15 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
                 // type a projection.
                 let in_trait = match opaque_ty.origin {
                     hir::OpaqueTyOrigin::FnReturn {
+                        parent,
                         in_trait_or_impl: Some(hir::RpitContext::Trait),
                         ..
                     }
                     | hir::OpaqueTyOrigin::AsyncFn {
+                        parent,
                         in_trait_or_impl: Some(hir::RpitContext::Trait),
                         ..
-                    } => true,
+                    } => Some(parent),
                     hir::OpaqueTyOrigin::FnReturn {
                         in_trait_or_impl: None | Some(hir::RpitContext::TraitImpl),
                         ..
@@ -2474,7 +2476,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
                         in_trait_or_impl: None | Some(hir::RpitContext::TraitImpl),
                         ..
                     }
-                    | hir::OpaqueTyOrigin::TyAlias { .. } => false,
+                    | hir::OpaqueTyOrigin::TyAlias { .. } => None,
                 };
 
                 self.lower_opaque_ty(opaque_ty.def_id, in_trait)
@@ -2594,17 +2596,25 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
 
     /// Lower an opaque type (i.e., an existential impl-Trait type) from the HIR.
     #[instrument(level = "debug", skip(self), ret)]
-    fn lower_opaque_ty(&self, def_id: LocalDefId, in_trait: bool) -> Ty<'tcx> {
+    fn lower_opaque_ty(&self, def_id: LocalDefId, in_trait: Option<LocalDefId>) -> Ty<'tcx> {
         let tcx = self.tcx();
 
         let lifetimes = tcx.opaque_captured_lifetimes(def_id);
         debug!(?lifetimes);
 
-        // If this is an RPITIT and we are using the new RPITIT lowering scheme, we
-        // generate the def_id of an associated type for the trait and return as
-        // type a projection.
-        let def_id = if in_trait {
-            tcx.associated_type_for_impl_trait_in_trait(def_id).to_def_id()
+        // If this is an RPITIT and we are using the new RPITIT lowering scheme,
+        // do a linear search to map this to the synthetic associated type that
+        // it will be lowered to.
+        let def_id = if let Some(parent_def_id) = in_trait {
+            *tcx.associated_types_for_impl_traits_in_associated_fn(parent_def_id)
+                .iter()
+                .find(|rpitit| match tcx.opt_rpitit_info(**rpitit) {
+                    Some(ty::ImplTraitInTraitData::Trait { opaque_def_id, .. }) => {
+                        opaque_def_id.expect_local() == def_id
+                    }
+                    _ => unreachable!(),
+                })
+                .unwrap()
         } else {
             def_id.to_def_id()
         };
@@ -2627,7 +2637,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
         });
         debug!(?args);
 
-        if in_trait {
+        if in_trait.is_some() {
             Ty::new_projection_from_args(tcx, def_id, args)
         } else {
             Ty::new_opaque(tcx, def_id, args)

compiler/rustc_hir_typeck/src/method/suggest.rs

@@ -1725,7 +1725,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             if unsatisfied_predicates.is_empty()
                 // ...or if we already suggested that name because of `rustc_confusable` annotation
                 && Some(similar_candidate.name()) != confusable_suggested
-                // and if the we aren't in an expansion.
+                // and if we aren't in an expansion.
                 && !span.from_expansion()
             {
                 self.find_likely_intended_associated_item(
@@ -3481,9 +3481,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         &self,
         err: &mut Diag<'_>,
         item_name: Ident,
-        valid_out_of_scope_traits: Vec<DefId>,
+        mut valid_out_of_scope_traits: Vec<DefId>,
         explain: bool,
     ) -> bool {
+        valid_out_of_scope_traits.retain(|id| self.tcx.is_user_visible_dep(id.krate));
         if !valid_out_of_scope_traits.is_empty() {
             let mut candidates = valid_out_of_scope_traits;
             candidates.sort_by_key(|id| self.tcx.def_path_str(id));
@@ -4388,7 +4389,7 @@ pub(crate) struct TraitInfo {
 /// Retrieves all traits in this crate and any dependent crates,
 /// and wraps them into `TraitInfo` for custom sorting.
 pub(crate) fn all_traits(tcx: TyCtxt<'_>) -> Vec<TraitInfo> {
-    tcx.all_traits().map(|def_id| TraitInfo { def_id }).collect()
+    tcx.all_traits_including_private().map(|def_id| TraitInfo { def_id }).collect()
 }
 
 fn print_disambiguation_help<'tcx>(

compiler/rustc_middle/src/query/mod.rs

@@ -1093,13 +1093,6 @@ rustc_queries! {
         separate_provide_extern
     }
 
-    /// Given an impl trait in trait `opaque_ty_def_id`, create and return the corresponding
-    /// associated item.
-    query associated_type_for_impl_trait_in_trait(opaque_ty_def_id: LocalDefId) -> LocalDefId {
-        desc { |tcx| "creating the associated item corresponding to the opaque type `{}`", tcx.def_path_str(opaque_ty_def_id.to_def_id()) }
-        cache_on_disk_if { true }
-    }
-
     /// Given an `impl_id`, return the trait it implements along with some header information.
     /// Return `None` if this is an inherent impl.
     query impl_trait_header(impl_id: DefId) -> Option<ty::ImplTraitHeader<'tcx>> {

compiler/rustc_middle/src/ty/context.rs

@@ -2288,7 +2288,7 @@ impl<'tcx> TyCtxt<'tcx> {
     }
 
     /// All traits in the crate graph, including those not visible to the user.
-    pub fn all_traits(self) -> impl Iterator<Item = DefId> {
+    pub fn all_traits_including_private(self) -> impl Iterator<Item = DefId> {
         iter::once(LOCAL_CRATE)
             .chain(self.crates(()).iter().copied())
             .flat_map(move |cnum| self.traits(cnum).iter().copied())

compiler/rustc_passes/messages.ftl

@@ -13,6 +13,10 @@ passes_abi_ne =
 passes_abi_of =
     fn_abi_of({$fn_name}) = {$fn_abi}
 
+passes_align_attr_application =
+    `#[align(...)]` should be applied to a function item
+    .label = not a function item
+
 passes_align_should_be_repr_align =
     `#[align(...)]` is not supported on {$item} items
     .suggestion = use `#[repr(align(...))]` instead