Rollup of 17 pull requests

compiler/rustc_borrowck/src/type_check/relate_tys.rs

@@ -124,8 +124,13 @@ impl<'a, 'b, 'tcx> NllTypeRelating<'a, 'b, 'tcx> {
         // by using `ty_vid rel B` and then finally and end by equating `ty_vid` to
         // the opaque.
         let mut enable_subtyping = |ty, opaque_is_expected| {
-            let ty_vid = infcx.next_ty_var_id_in_universe(self.span(), ty::UniverseIndex::ROOT);
-
+            // We create the fresh inference variable in the highest universe.
+            // In theory we could limit it to the highest universe in the args of
+            // the opaque but that isn't really worth the effort.
+            //
+            // We'll make sure that the opaque type can actually name everything
+            // in its hidden type later on.
+            let ty_vid = infcx.next_ty_vid(self.span());
             let variance = if opaque_is_expected {
                 self.ambient_variance
             } else {

compiler/rustc_builtin_macros/src/lib.rs

@@ -8,7 +8,6 @@
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![doc(rust_logo)]
 #![feature(assert_matches)]
-#![feature(autodiff)]
 #![feature(box_patterns)]
 #![feature(decl_macro)]
 #![feature(if_let_guard)]

compiler/rustc_codegen_llvm/src/attributes.rs

@@ -497,7 +497,7 @@ pub(crate) fn llfn_attrs_from_instance<'ll, 'tcx>(
             to_add.push(llvm::CreateAttrStringValue(cx.llcx, "wasm-import-module", module));
 
             let name =
-                codegen_fn_attrs.link_name.unwrap_or_else(|| cx.tcx.item_name(instance.def_id()));
+                codegen_fn_attrs.symbol_name.unwrap_or_else(|| cx.tcx.item_name(instance.def_id()));
             let name = name.as_str();
             to_add.push(llvm::CreateAttrStringValue(cx.llcx, "wasm-import-name", name));
         }

compiler/rustc_codegen_llvm/src/context.rs

@@ -471,6 +471,15 @@ pub(crate) unsafe fn create_module<'ll>(
         }
     }
 
+    if sess.opts.unstable_opts.indirect_branch_cs_prefix {
+        llvm::add_module_flag_u32(
+            llmod,
+            llvm::ModuleFlagMergeBehavior::Override,
+            "indirect_branch_cs_prefix",
+            1,
+        );
+    }
+
     match (sess.opts.unstable_opts.small_data_threshold, sess.target.small_data_threshold_support())
     {
         // Set up the small-data optimization limit for architectures that use

compiler/rustc_codegen_llvm/src/llvm_util.rs

@@ -277,6 +277,7 @@ pub(crate) fn to_llvm_features<'a>(sess: &Session, s: &'a str) -> Option<LLVMFea
         {
             None
         }
+        ("loongarch32" | "loongarch64", "32s") if get_version().0 < 21 => None,
         // Filter out features that are not supported by the current LLVM version
         ("riscv32" | "riscv64", "zacas") if get_version().0 < 20 => None,
         (

compiler/rustc_codegen_ssa/src/base.rs

@@ -858,7 +858,7 @@ pub fn is_call_from_compiler_builtins_to_upstream_monomorphization<'tcx>(
     instance: Instance<'tcx>,
 ) -> bool {
     fn is_llvm_intrinsic(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
-        if let Some(name) = tcx.codegen_fn_attrs(def_id).link_name {
+        if let Some(name) = tcx.codegen_fn_attrs(def_id).symbol_name {
             name.as_str().starts_with("llvm.")
         } else {
             false

compiler/rustc_codegen_ssa/src/codegen_attrs.rs

@@ -6,7 +6,6 @@ use rustc_ast::{LitKind, MetaItem, MetaItemInner, attr};
 use rustc_hir::attrs::{AttributeKind, InlineAttr, InstructionSetAttr, UsedBy};
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LOCAL_CRATE, LocalDefId};
-use rustc_hir::weak_lang_items::WEAK_LANG_ITEMS;
 use rustc_hir::{self as hir, Attribute, LangItem, find_attr, lang_items};
 use rustc_middle::middle::codegen_fn_attrs::{
     CodegenFnAttrFlags, CodegenFnAttrs, PatchableFunctionEntry,
@@ -156,15 +155,21 @@ fn process_builtin_attrs(
             match p {
                 AttributeKind::Cold(_) => codegen_fn_attrs.flags |= CodegenFnAttrFlags::COLD,
                 AttributeKind::ExportName { name, .. } => {
-                    codegen_fn_attrs.export_name = Some(*name)
+                    codegen_fn_attrs.symbol_name = Some(*name)
                 }
                 AttributeKind::Inline(inline, span) => {
                     codegen_fn_attrs.inline = *inline;
                     interesting_spans.inline = Some(*span);
                 }
                 AttributeKind::Naked(_) => codegen_fn_attrs.flags |= CodegenFnAttrFlags::NAKED,
                 AttributeKind::Align { align, .. } => codegen_fn_attrs.alignment = Some(*align),
-                AttributeKind::LinkName { name, .. } => codegen_fn_attrs.link_name = Some(*name),
+                AttributeKind::LinkName { name, .. } => {
+                    // FIXME Remove check for foreign functions once #[link_name] on non-foreign
+                    // functions is a hard error
+                    if tcx.is_foreign_item(did) {
+                        codegen_fn_attrs.symbol_name = Some(*name);
+                    }
+                }
                 AttributeKind::LinkOrdinal { ordinal, span } => {
                     codegen_fn_attrs.link_ordinal = Some(*ordinal);
                     interesting_spans.link_ordinal = Some(*span);
@@ -382,7 +387,7 @@ fn apply_overrides(tcx: TyCtxt<'_>, did: LocalDefId, codegen_fn_attrs: &mut Code
             // * `#[rustc_std_internal_symbol]` mangles the symbol name in a special way
             //   both for exports and imports through foreign items. This is handled further,
             //   during symbol mangling logic.
-        } else if codegen_fn_attrs.link_name.is_some() {
+        } else if codegen_fn_attrs.symbol_name.is_some() {
             // * This can be overridden with the `#[link_name]` attribute
         } else {
             // NOTE: there's one more exception that we cannot apply here. On wasm,
@@ -437,7 +442,7 @@ fn check_result(
     }
 
     // error when specifying link_name together with link_ordinal
-    if let Some(_) = codegen_fn_attrs.link_name
+    if let Some(_) = codegen_fn_attrs.symbol_name
         && let Some(_) = codegen_fn_attrs.link_ordinal
     {
         let msg = "cannot use `#[link_name]` with `#[link_ordinal]`";
@@ -484,14 +489,11 @@ fn handle_lang_items(
     // strippable by the linker.
     //
     // Additionally weak lang items have predetermined symbol names.
-    if let Some(lang_item) = lang_item {
-        if WEAK_LANG_ITEMS.contains(&lang_item) {
-            codegen_fn_attrs.flags |= CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL;
-        }
-        if let Some(link_name) = lang_item.link_name() {
-            codegen_fn_attrs.export_name = Some(link_name);
-            codegen_fn_attrs.link_name = Some(link_name);
-        }
+    if let Some(lang_item) = lang_item
+        && let Some(link_name) = lang_item.link_name()
+    {
+        codegen_fn_attrs.flags |= CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL;
+        codegen_fn_attrs.symbol_name = Some(link_name);
     }
 
     // error when using no_mangle on a lang item item

compiler/rustc_codegen_ssa/src/target_features.rs

@@ -180,6 +180,7 @@ fn parse_rust_feature_flag<'a>(
             while let Some(new_feature) = new_features.pop() {
                 if features.insert(new_feature) {
                     if let Some(implied_features) = inverse_implied_features.get(&new_feature) {
+                        #[allow(rustc::potential_query_instability)]
                         new_features.extend(implied_features)
                     }
                 }

compiler/rustc_const_eval/src/interpret/call.rs

@@ -27,8 +27,9 @@ use crate::{enter_trace_span, fluent_generated as fluent};
 pub enum FnArg<'tcx, Prov: Provenance = CtfeProvenance> {
     /// Pass a copy of the given operand.
     Copy(OpTy<'tcx, Prov>),
-    /// Allow for the argument to be passed in-place: destroy the value originally stored at that place and
-    /// make the place inaccessible for the duration of the function call.
+    /// Allow for the argument to be passed in-place: destroy the value originally stored at that
+    /// place and make the place inaccessible for the duration of the function call. This *must* be
+    /// an in-memory place so that we can do the proper alias checks.
     InPlace(MPlaceTy<'tcx, Prov>),
 }
 
@@ -379,6 +380,11 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             }
         }
 
+        // *Before* pushing the new frame, determine whether the return destination is in memory.
+        // Need to use `place_to_op` to be *sure* we get the mplace if there is one.
+        let destination_mplace = self.place_to_op(destination)?.as_mplace_or_imm().left();
+
+        // Push the "raw" frame -- this leaves locals uninitialized.
         self.push_stack_frame_raw(instance, body, destination, cont)?;
 
         // If an error is raised here, pop the frame again to get an accurate backtrace.
@@ -496,7 +502,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
 
             // Protect return place for in-place return value passing.
             // We only need to protect anything if this is actually an in-memory place.
-            if let Left(mplace) = destination.as_mplace_or_local() {
+            if let Some(mplace) = destination_mplace {
                 M::protect_in_place_function_argument(self, &mplace)?;
             }
 

compiler/rustc_const_eval/src/interpret/eval_context.rs

@@ -325,8 +325,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         let _trace = enter_trace_span!(
             M,
             "instantiate_from_frame_and_normalize_erasing_regions",
-            "{}",
-            frame.instance
+            %frame.instance
         );
         frame
             .instance
@@ -583,6 +582,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         span: Span,
         layout: Option<TyAndLayout<'tcx>>,
     ) -> InterpResult<'tcx, OpTy<'tcx, M::Provenance>> {
+        let _trace = enter_trace_span!(M, const_eval::eval_mir_constant, ?val);
         let const_val = val.eval(*self.tcx, self.typing_env, span).map_err(|err| {
                 if M::ALL_CONSTS_ARE_PRECHECKED {
                     match err {

compiler/rustc_const_eval/src/interpret/place.rs

@@ -234,6 +234,12 @@ impl<'tcx, Prov: Provenance> PlaceTy<'tcx, Prov> {
     }
 
     /// A place is either an mplace or some local.
+    ///
+    /// Note that the return value can be different even for logically identical places!
+    /// Specifically, if a local is stored in-memory, this may return `Local` or `MPlaceTy`
+    /// depending on how the place was constructed. In other words, seeing `Local` here does *not*
+    /// imply that this place does not point to memory. Every caller must therefore always handle
+    /// both cases.
     #[inline(always)]
     pub fn as_mplace_or_local(
         &self,

compiler/rustc_const_eval/src/interpret/stack.rs

@@ -20,7 +20,7 @@ use super::{
     MemoryKind, Operand, PlaceTy, Pointer, Provenance, ReturnAction, Scalar, from_known_layout,
     interp_ok, throw_ub, throw_unsup,
 };
-use crate::errors;
+use crate::{enter_trace_span, errors};
 
 // The Phantomdata exists to prevent this type from being `Send`. If it were sent across a thread
 // boundary and dropped in the other thread, it would exit the span in the other thread.
@@ -386,6 +386,9 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
 
         // Make sure all the constants required by this frame evaluate successfully (post-monomorphization check).
         for &const_ in body.required_consts() {
+            // We can't use `eval_mir_constant` here as that assumes that all required consts have
+            // already been checked, so we need a separate tracing call.
+            let _trace = enter_trace_span!(M, const_eval::required_consts, ?const_.const_);
             let c =
                 self.instantiate_from_current_frame_and_normalize_erasing_regions(const_.const_)?;
             c.eval(*self.tcx, self.typing_env, const_.span).map_err(|err| {

compiler/rustc_const_eval/src/interpret/step.rs

@@ -4,6 +4,7 @@
 
 use either::Either;
 use rustc_abi::{FIRST_VARIANT, FieldIdx};
+use rustc_data_structures::fx::FxHashSet;
 use rustc_index::IndexSlice;
 use rustc_middle::ty::{self, Instance, Ty};
 use rustc_middle::{bug, mir, span_bug};
@@ -389,8 +390,9 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
 
     /// Evaluate the arguments of a function call
     fn eval_fn_call_argument(
-        &self,
+        &mut self,
         op: &mir::Operand<'tcx>,
+        move_definitely_disjoint: bool,
     ) -> InterpResult<'tcx, FnArg<'tcx, M::Provenance>> {
         interp_ok(match op {
             mir::Operand::Copy(_) | mir::Operand::Constant(_) => {
@@ -399,24 +401,19 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
                 FnArg::Copy(op)
             }
             mir::Operand::Move(place) => {
-                // If this place lives in memory, preserve its location.
-                // We call `place_to_op` which will be an `MPlaceTy` whenever there exists
-                // an mplace for this place. (This is in contrast to `PlaceTy::as_mplace_or_local`
-                // which can return a local even if that has an mplace.)
                 let place = self.eval_place(*place)?;
-                let op = self.place_to_op(&place)?;
-
-                match op.as_mplace_or_imm() {
-                    Either::Left(mplace) => FnArg::InPlace(mplace),
-                    Either::Right(_imm) => {
-                        // This argument doesn't live in memory, so there's no place
-                        // to make inaccessible during the call.
-                        // We rely on there not being any stray `PlaceTy` that would let the
-                        // caller directly access this local!
-                        // This is also crucial for tail calls, where we want the `FnArg` to
-                        // stay valid when the old stack frame gets popped.
-                        FnArg::Copy(op)
+                if move_definitely_disjoint {
+                    // We still have to ensure that no *other* pointers are used to access this place,
+                    // so *if* it is in memory then we have to treat it as `InPlace`.
+                    // Use `place_to_op` to guarantee that we notice it being in memory.
+                    let op = self.place_to_op(&place)?;
+                    match op.as_mplace_or_imm() {
+                        Either::Left(mplace) => FnArg::InPlace(mplace),
+                        Either::Right(_imm) => FnArg::Copy(op),
                     }
+                } else {
+                    // We have to force this into memory to detect aliasing among `Move` arguments.
+                    FnArg::InPlace(self.force_allocation(&place)?)
                 }
             }
         })
@@ -425,18 +422,46 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
     /// Shared part of `Call` and `TailCall` implementation — finding and evaluating all the
     /// necessary information about callee and arguments to make a call.
     fn eval_callee_and_args(
-        &self,
+        &mut self,
         terminator: &mir::Terminator<'tcx>,
         func: &mir::Operand<'tcx>,
         args: &[Spanned<mir::Operand<'tcx>>],
     ) -> InterpResult<'tcx, EvaluatedCalleeAndArgs<'tcx, M>> {
         let func = self.eval_operand(func, None)?;
+
+        // Evaluating function call arguments. The tricky part here is dealing with `Move`
+        // arguments: we have to ensure no two such arguments alias. This would be most easily done
+        // by just forcing them all into memory and then doing the usual in-place argument
+        // protection, but then we'd force *a lot* of arguments into memory. So we do some syntactic
+        // pre-processing here where if all `move` arguments are syntactically distinct local
+        // variables (and none is indirect), we can skip the in-memory forcing.
+        let move_definitely_disjoint = 'move_definitely_disjoint: {
+            let mut previous_locals = FxHashSet::<mir::Local>::default();
+            for arg in args {
+                let mir::Operand::Move(place) = arg.node else {
+                    continue; // we can skip non-`Move` arguments.
+                };
+                if place.is_indirect_first_projection() {
+                    // An indirect `Move` argument could alias with anything else...
+                    break 'move_definitely_disjoint false;
+                }
+                if !previous_locals.insert(place.local) {
+                    // This local is the base for two arguments! They might overlap.
+                    break 'move_definitely_disjoint false;
+                }
+            }
+            // We found no violation so they are all definitely disjoint.
+            true
+        };
         let args = args
             .iter()
-            .map(|arg| self.eval_fn_call_argument(&arg.node))
+            .map(|arg| self.eval_fn_call_argument(&arg.node, move_definitely_disjoint))
             .collect::<InterpResult<'tcx, Vec<_>>>()?;
 
-        let fn_sig_binder = func.layout.ty.fn_sig(*self.tcx);
+        let fn_sig_binder = {
+            let _trace = enter_trace_span!(M, "fn_sig", ty = ?func.layout.ty.kind());
+            func.layout.ty.fn_sig(*self.tcx)
+        };
         let fn_sig = self.tcx.normalize_erasing_late_bound_regions(self.typing_env, fn_sig_binder);
         let extra_args = &args[fn_sig.inputs().len()..];
         let extra_args =

compiler/rustc_const_eval/src/interpret/validity.rs

@@ -1418,7 +1418,9 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         let _trace = enter_trace_span!(
             M,
             "validate_operand",
-            "recursive={recursive}, reset_provenance_and_padding={reset_provenance_and_padding}, val={val:?}"
+            recursive,
+            reset_provenance_and_padding,
+            ?val,
         );
 
         // Note that we *could* actually be in CTFE here with `-Zextra-const-ub-checks`, but it's

compiler/rustc_errors/src/emitter.rs

@@ -17,7 +17,7 @@ use std::path::Path;
 use std::sync::Arc;
 
 use derive_setters::Setters;
-use rustc_data_structures::fx::{FxHashMap, FxIndexMap, FxIndexSet};
+use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
 use rustc_data_structures::sync::{DynSend, IntoDynSyncSend};
 use rustc_error_messages::{FluentArgs, SpanLabel};
 use rustc_lexer;
@@ -1853,7 +1853,7 @@ impl HumanEmitter {
                             && line_idx + 1 == annotated_file.lines.len(),
                     );
 
-                    let mut to_add = FxHashMap::default();
+                    let mut to_add = FxIndexMap::default();
 
                     for (depth, style) in depths {
                         // FIXME(#120456) - is `swap_remove` correct?

compiler/rustc_expand/src/mbe/macro_rules.rs

@@ -596,6 +596,7 @@ pub(super) fn try_match_macro_attr<'matcher, T: Tracker<'matcher>>(
         match result {
             Success(body_named_matches) => {
                 psess.gated_spans.merge(gated_spans_snapshot);
+                #[allow(rustc::potential_query_instability)]
                 named_matches.extend(body_named_matches);
                 return Ok((i, rule, named_matches));
             }