Auto merge of #128796 - matthiaskrgr:rollup-r7l68ph, r=matthiaskrgr

Rollup of 8 pull requests

Successful merges:

 - #128221 (Add implied target features to target_feature attribute)
 - #128261 (impl `Default` for collection iterators that don't already have it)
 - #128353 (Change generate-copyright to generate HTML, with cargo dependencies included)
 - #128679 (codegen: better centralize function declaration attribute computation)
 - #128732 (make `import.vis` is immutable)
 - #128755 (Integrate crlf directly into related test file instead via of .gitattributes)
 - #128772 (rustc_codegen_ssa: Set architecture for object crate for 32-bit SPARC)
 - #128782 (unused_parens: do not lint against parens around &raw)

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

Cargo.lock

@@ -1406,8 +1406,11 @@ name = "generate-copyright"
 version = "0.1.0"
 dependencies = [
  "anyhow",
+ "cargo_metadata 0.18.1",
+ "rinja",
  "serde",
  "serde_json",
+ "thiserror",
 ]
 
 [[package]]
@@ -3094,7 +3097,10 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6d3762e3740cdbf2fd2be465cc2c26d643ad17353cc2e0223d211c1b096118bd"
 dependencies = [
+ "humansize",
  "itoa",
+ "num-traits",
+ "percent-encoding",
  "rinja_derive",
 ]
 

REUSE.toml

@@ -163,7 +163,7 @@ SPDX-License-Identifier = "MIT OR Apache-2.0"
 path = "src/llvm-project/**"
 precedence = "override"
 SPDX-FileCopyrightText = [
-    "2003-2019 by the contributors listed in [CREDITS.TXT](https://github.com/rust-lang/llvm-project/blob/7738295178045041669876bf32b0543ec8319a5c/llvm/CREDITS.TXT)",
+    "2003-2019 by the contributors listed in CREDITS.TXT (https://github.com/rust-lang/llvm-project/blob/7738295178045041669876bf32b0543ec8319a5c/llvm/CREDITS.TXT)",
     "2010 Apple Inc",
     "2003-2019 University of Illinois at Urbana-Champaign.",
 ]

compiler/rustc_codegen_gcc/src/attributes.rs

@@ -75,7 +75,7 @@ pub fn from_fn_attrs<'gcc, 'tcx>(
     let function_features = codegen_fn_attrs
         .target_features
         .iter()
-        .map(|features| features.as_str())
+        .map(|features| features.name.as_str())
         .collect::<Vec<&str>>();
 
     if let Some(features) = check_tied_features(

compiler/rustc_codegen_gcc/src/gcc_util.rs

@@ -65,8 +65,8 @@ pub(crate) fn global_gcc_features(sess: &Session, diagnostics: bool) -> Vec<Stri
 
             let feature = backend_feature_name(s)?;
             // Warn against use of GCC specific feature names on the CLI.
-            if diagnostics && !supported_features.iter().any(|&(v, _)| v == feature) {
-                let rust_feature = supported_features.iter().find_map(|&(rust_feature, _)| {
+            if diagnostics && !supported_features.iter().any(|&(v, _, _)| v == feature) {
+                let rust_feature = supported_features.iter().find_map(|&(rust_feature, _, _)| {
                     let gcc_features = to_gcc_features(sess, rust_feature);
                     if gcc_features.contains(&feature) && !gcc_features.contains(&rust_feature) {
                         Some(rust_feature)

compiler/rustc_codegen_gcc/src/lib.rs

@@ -486,7 +486,7 @@ pub fn target_features(
     sess.target
         .supported_target_features()
         .iter()
-        .filter_map(|&(feature, gate)| {
+        .filter_map(|&(feature, gate, _)| {
             if sess.is_nightly_build() || allow_unstable || gate.is_stable() {
                 Some(feature)
             } else {

compiler/rustc_codegen_llvm/src/abi.rs

@@ -5,10 +5,10 @@ use rustc_codegen_ssa::mir::operand::{OperandRef, OperandValue};
 use rustc_codegen_ssa::mir::place::{PlaceRef, PlaceValue};
 use rustc_codegen_ssa::traits::*;
 use rustc_codegen_ssa::MemFlags;
-use rustc_middle::bug;
 use rustc_middle::ty::layout::LayoutOf;
 pub use rustc_middle::ty::layout::{FAT_PTR_ADDR, FAT_PTR_EXTRA};
 use rustc_middle::ty::Ty;
+use rustc_middle::{bug, ty};
 use rustc_session::config;
 pub use rustc_target::abi::call::*;
 use rustc_target::abi::{self, HasDataLayout, Int, Size};
@@ -16,6 +16,7 @@ pub use rustc_target::spec::abi::Abi;
 use rustc_target::spec::SanitizerSet;
 use smallvec::SmallVec;
 
+use crate::attributes::llfn_attrs_from_instance;
 use crate::builder::Builder;
 use crate::context::CodegenCx;
 use crate::llvm::{self, Attribute, AttributePlace};
@@ -310,7 +311,16 @@ pub trait FnAbiLlvmExt<'ll, 'tcx> {
     fn llvm_type(&self, cx: &CodegenCx<'ll, 'tcx>) -> &'ll Type;
     fn ptr_to_llvm_type(&self, cx: &CodegenCx<'ll, 'tcx>) -> &'ll Type;
     fn llvm_cconv(&self) -> llvm::CallConv;
-    fn apply_attrs_llfn(&self, cx: &CodegenCx<'ll, 'tcx>, llfn: &'ll Value);
+
+    /// Apply attributes to a function declaration/definition.
+    fn apply_attrs_llfn(
+        &self,
+        cx: &CodegenCx<'ll, 'tcx>,
+        llfn: &'ll Value,
+        instance: Option<ty::Instance<'tcx>>,
+    );
+
+    /// Apply attributes to a function call.
     fn apply_attrs_callsite(&self, bx: &mut Builder<'_, 'll, 'tcx>, callsite: &'ll Value);
 }
 
@@ -396,7 +406,12 @@ impl<'ll, 'tcx> FnAbiLlvmExt<'ll, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
         self.conv.into()
     }
 
-    fn apply_attrs_llfn(&self, cx: &CodegenCx<'ll, 'tcx>, llfn: &'ll Value) {
+    fn apply_attrs_llfn(
+        &self,
+        cx: &CodegenCx<'ll, 'tcx>,
+        llfn: &'ll Value,
+        instance: Option<ty::Instance<'tcx>>,
+    ) {
         let mut func_attrs = SmallVec::<[_; 3]>::new();
         if self.ret.layout.abi.is_uninhabited() {
             func_attrs.push(llvm::AttributeKind::NoReturn.create_attr(cx.llcx));
@@ -477,6 +492,11 @@ impl<'ll, 'tcx> FnAbiLlvmExt<'ll, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
                 }
             }
         }
+
+        // If the declaration has an associated instance, compute extra attributes based on that.
+        if let Some(instance) = instance {
+            llfn_attrs_from_instance(cx, llfn, instance);
+        }
     }
 
     fn apply_attrs_callsite(&self, bx: &mut Builder<'_, 'll, 'tcx>, callsite: &'ll Value) {

compiler/rustc_codegen_llvm/src/attributes.rs

@@ -324,9 +324,10 @@ fn create_alloc_family_attr(llcx: &llvm::Context) -> &llvm::Attribute {
     llvm::CreateAttrStringValue(llcx, "alloc-family", "__rust_alloc")
 }
 
+/// Helper for `FnAbi::apply_attrs_llfn`:
 /// Composite function which sets LLVM attributes for function depending on its AST (`#[attribute]`)
 /// attributes.
-pub fn from_fn_attrs<'ll, 'tcx>(
+pub fn llfn_attrs_from_instance<'ll, 'tcx>(
     cx: &CodegenCx<'ll, 'tcx>,
     llfn: &'ll Value,
     instance: ty::Instance<'tcx>,
@@ -496,7 +497,7 @@ pub fn from_fn_attrs<'ll, 'tcx>(
     to_add.extend(tune_cpu_attr(cx));
 
     let function_features =
-        codegen_fn_attrs.target_features.iter().map(|f| f.as_str()).collect::<Vec<&str>>();
+        codegen_fn_attrs.target_features.iter().map(|f| f.name.as_str()).collect::<Vec<&str>>();
 
     if let Some(f) = llvm_util::check_tied_features(
         cx.tcx.sess,

compiler/rustc_codegen_llvm/src/back/write.rs

@@ -95,11 +95,14 @@ pub fn write_output_file<'ll>(
     }
 }
 
-pub fn create_informational_target_machine(sess: &Session) -> OwnedTargetMachine {
+pub fn create_informational_target_machine(
+    sess: &Session,
+    only_base_features: bool,
+) -> OwnedTargetMachine {
     let config = TargetMachineFactoryConfig { split_dwarf_file: None, output_obj_file: None };
     // Can't use query system here quite yet because this function is invoked before the query
     // system/tcx is set up.
-    let features = llvm_util::global_llvm_features(sess, false);
+    let features = llvm_util::global_llvm_features(sess, false, only_base_features);
     target_machine_factory(sess, config::OptLevel::No, &features)(config)
         .unwrap_or_else(|err| llvm_err(sess.dcx(), err).raise())
 }

compiler/rustc_codegen_llvm/src/callee.rs

@@ -10,8 +10,8 @@ use rustc_middle::ty::{self, Instance, TypeVisitableExt};
 use tracing::debug;
 
 use crate::context::CodegenCx;
+use crate::llvm;
 use crate::value::Value;
-use crate::{attributes, llvm};
 
 /// Codegens a reference to a fn/method item, monomorphizing and
 /// inlining as it goes.
@@ -78,8 +78,6 @@ pub fn get_fn<'ll, 'tcx>(cx: &CodegenCx<'ll, 'tcx>, instance: Instance<'tcx>) ->
         };
         debug!("get_fn: not casting pointer!");
 
-        attributes::from_fn_attrs(cx, llfn, instance);
-
         // Apply an appropriate linkage/visibility value to our item that we
         // just declared.
         //

compiler/rustc_codegen_llvm/src/context.rs

@@ -149,7 +149,7 @@ pub unsafe fn create_module<'ll>(
 
     // Ensure the data-layout values hardcoded remain the defaults.
     {
-        let tm = crate::back::write::create_informational_target_machine(tcx.sess);
+        let tm = crate::back::write::create_informational_target_machine(tcx.sess, false);
         unsafe {
             llvm::LLVMRustSetDataLayoutFromTargetMachine(llmod, &tm);
         }

compiler/rustc_codegen_llvm/src/declare.rs

@@ -137,7 +137,7 @@ impl<'ll, 'tcx> CodegenCx<'ll, 'tcx> {
             llvm::Visibility::Default,
             fn_abi.llvm_type(self),
         );
-        fn_abi.apply_attrs_llfn(self, llfn);
+        fn_abi.apply_attrs_llfn(self, llfn, instance);
 
         if self.tcx.sess.is_sanitizer_cfi_enabled() {
             if let Some(instance) = instance {

compiler/rustc_codegen_llvm/src/lib.rs

@@ -269,7 +269,7 @@ impl CodegenBackend for LlvmCodegenBackend {
 
     fn provide(&self, providers: &mut Providers) {
         providers.global_backend_features =
-            |tcx, ()| llvm_util::global_llvm_features(tcx.sess, true)
+            |tcx, ()| llvm_util::global_llvm_features(tcx.sess, true, false)
     }
 
     fn print(&self, req: &PrintRequest, out: &mut String, sess: &Session) {
@@ -434,7 +434,7 @@ impl ModuleLlvm {
             ModuleLlvm {
                 llmod_raw,
                 llcx,
-                tm: ManuallyDrop::new(create_informational_target_machine(tcx.sess)),
+                tm: ManuallyDrop::new(create_informational_target_machine(tcx.sess, false)),
             }
         }
     }

compiler/rustc_codegen_llvm/src/llvm_util.rs

@@ -8,6 +8,7 @@ use libc::c_int;
 use rustc_codegen_ssa::base::wants_wasm_eh;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::small_c_str::SmallCStr;
+use rustc_data_structures::unord::UnordSet;
 use rustc_fs_util::path_to_c_string;
 use rustc_middle::bug;
 use rustc_session::config::{PrintKind, PrintRequest};
@@ -239,40 +240,8 @@ pub fn to_llvm_features<'a>(sess: &Session, s: &'a str) -> LLVMFeature<'a> {
         }
         // In LLVM neon implicitly enables fp, but we manually enable
         // neon when a feature only implicitly enables fp
-        ("aarch64", "f32mm") => {
-            LLVMFeature::with_dependency("f32mm", TargetFeatureFoldStrength::EnableOnly("neon"))
-        }
-        ("aarch64", "f64mm") => {
-            LLVMFeature::with_dependency("f64mm", TargetFeatureFoldStrength::EnableOnly("neon"))
-        }
-        ("aarch64", "fhm") => {
-            LLVMFeature::with_dependency("fp16fml", TargetFeatureFoldStrength::EnableOnly("neon"))
-        }
-        ("aarch64", "fp16") => {
-            LLVMFeature::with_dependency("fullfp16", TargetFeatureFoldStrength::EnableOnly("neon"))
-        }
-        ("aarch64", "jsconv") => {
-            LLVMFeature::with_dependency("jsconv", TargetFeatureFoldStrength::EnableOnly("neon"))
-        }
-        ("aarch64", "sve") => {
-            LLVMFeature::with_dependency("sve", TargetFeatureFoldStrength::EnableOnly("neon"))
-        }
-        ("aarch64", "sve2") => {
-            LLVMFeature::with_dependency("sve2", TargetFeatureFoldStrength::EnableOnly("neon"))
-        }
-        ("aarch64", "sve2-aes") => {
-            LLVMFeature::with_dependency("sve2-aes", TargetFeatureFoldStrength::EnableOnly("neon"))
-        }
-        ("aarch64", "sve2-sm4") => {
-            LLVMFeature::with_dependency("sve2-sm4", TargetFeatureFoldStrength::EnableOnly("neon"))
-        }
-        ("aarch64", "sve2-sha3") => {
-            LLVMFeature::with_dependency("sve2-sha3", TargetFeatureFoldStrength::EnableOnly("neon"))
-        }
-        ("aarch64", "sve2-bitperm") => LLVMFeature::with_dependency(
-            "sve2-bitperm",
-            TargetFeatureFoldStrength::EnableOnly("neon"),
-        ),
+        ("aarch64", "fhm") => LLVMFeature::new("fp16fml"),
+        ("aarch64", "fp16") => LLVMFeature::new("fullfp16"),
         // In LLVM 18, `unaligned-scalar-mem` was merged with `unaligned-vector-mem` into a single feature called
         // `fast-unaligned-access`. In LLVM 19, it was split back out.
         ("riscv32" | "riscv64", "unaligned-scalar-mem") if get_version().0 == 18 => {
@@ -308,11 +277,53 @@ pub fn check_tied_features(
 /// Used to generate cfg variables and apply features
 /// Must express features in the way Rust understands them
 pub fn target_features(sess: &Session, allow_unstable: bool) -> Vec<Symbol> {
-    let target_machine = create_informational_target_machine(sess);
+    let mut features = vec![];
+
+    // Add base features for the target
+    let target_machine = create_informational_target_machine(sess, true);
+    features.extend(
+        sess.target
+            .supported_target_features()
+            .iter()
+            .filter(|(feature, _, _)| {
+                // skip checking special features, as LLVM may not understands them
+                if RUSTC_SPECIAL_FEATURES.contains(feature) {
+                    return true;
+                }
+                // check that all features in a given smallvec are enabled
+                for llvm_feature in to_llvm_features(sess, feature) {
+                    let cstr = SmallCStr::new(llvm_feature);
+                    if !unsafe { llvm::LLVMRustHasFeature(&target_machine, cstr.as_ptr()) } {
+                        return false;
+                    }
+                }
+                true
+            })
+            .map(|(feature, _, _)| Symbol::intern(feature)),
+    );
+
+    // Add enabled features
+    for (enabled, feature) in
+        sess.opts.cg.target_feature.split(',').filter_map(|s| match s.chars().next() {
+            Some('+') => Some((true, Symbol::intern(&s[1..]))),
+            Some('-') => Some((false, Symbol::intern(&s[1..]))),
+            _ => None,
+        })
+    {
+        if enabled {
+            features.extend(sess.target.implied_target_features(std::iter::once(feature)));
+        } else {
+            features.retain(|f| {
+                !sess.target.implied_target_features(std::iter::once(*f)).contains(&feature)
+            });
+        }
+    }
+
+    // Filter enabled features based on feature gates
     sess.target
         .supported_target_features()
         .iter()
-        .filter_map(|&(feature, gate)| {
+        .filter_map(|&(feature, gate, _)| {
             if sess.is_nightly_build() || allow_unstable || gate.is_stable() {
                 Some(feature)
             } else {
@@ -320,18 +331,7 @@ pub fn target_features(sess: &Session, allow_unstable: bool) -> Vec<Symbol> {
             }
         })
         .filter(|feature| {
-            // skip checking special features, as LLVM may not understands them
-            if RUSTC_SPECIAL_FEATURES.contains(feature) {
-                return true;
-            }
-            // check that all features in a given smallvec are enabled
-            for llvm_feature in to_llvm_features(sess, feature) {
-                let cstr = SmallCStr::new(llvm_feature);
-                if !unsafe { llvm::LLVMRustHasFeature(&target_machine, cstr.as_ptr()) } {
-                    return false;
-                }
-            }
-            true
+            RUSTC_SPECIAL_FEATURES.contains(feature) || features.contains(&Symbol::intern(feature))
         })
         .map(|feature| Symbol::intern(feature))
         .collect()
@@ -386,7 +386,7 @@ fn print_target_features(out: &mut String, sess: &Session, tm: &llvm::TargetMach
         .target
         .supported_target_features()
         .iter()
-        .map(|(feature, _gate)| {
+        .map(|(feature, _gate, _implied)| {
             // LLVM asserts that these are sorted. LLVM and Rust both use byte comparison for these strings.
             let llvm_feature = to_llvm_features(sess, *feature).llvm_feature_name;
             let desc =
@@ -440,7 +440,7 @@ fn print_target_features(out: &mut String, sess: &Session, tm: &llvm::TargetMach
 
 pub(crate) fn print(req: &PrintRequest, mut out: &mut String, sess: &Session) {
     require_inited();
-    let tm = create_informational_target_machine(sess);
+    let tm = create_informational_target_machine(sess, false);
     match req.kind {
         PrintKind::TargetCPUs => {
             // SAFETY generate a C compatible string from a byte slice to pass
@@ -488,7 +488,11 @@ pub fn target_cpu(sess: &Session) -> &str {
 
 /// The list of LLVM features computed from CLI flags (`-Ctarget-cpu`, `-Ctarget-feature`,
 /// `--target` and similar).
-pub(crate) fn global_llvm_features(sess: &Session, diagnostics: bool) -> Vec<String> {
+pub(crate) fn global_llvm_features(
+    sess: &Session,
+    diagnostics: bool,
+    only_base_features: bool,
+) -> Vec<String> {
     // Features that come earlier are overridden by conflicting features later in the string.
     // Typically we'll want more explicit settings to override the implicit ones, so:
     //
@@ -548,94 +552,124 @@ pub(crate) fn global_llvm_features(sess: &Session, diagnostics: bool) -> Vec<Str
     }
 
     // -Ctarget-features
-    let supported_features = sess.target.supported_target_features();
-    let (llvm_major, _, _) = get_version();
-    let mut featsmap = FxHashMap::default();
-    let feats = sess
-        .opts
-        .cg
-        .target_feature
-        .split(',')
-        .filter_map(|s| {
-            let enable_disable = match s.chars().next() {
-                None => return None,
-                Some(c @ ('+' | '-')) => c,
-                Some(_) => {
-                    if diagnostics {
-                        sess.dcx().emit_warn(UnknownCTargetFeaturePrefix { feature: s });
+    if !only_base_features {
+        let supported_features = sess.target.supported_target_features();
+        let (llvm_major, _, _) = get_version();
+        let mut featsmap = FxHashMap::default();
+
+        // insert implied features
+        let mut all_rust_features = vec![];
+        for feature in sess.opts.cg.target_feature.split(',') {
+            match feature.strip_prefix('+') {
+                Some(feature) => all_rust_features.extend(
+                    UnordSet::from(
+                        sess.target
+                            .implied_target_features(std::iter::once(Symbol::intern(feature))),
+                    )
+                    .to_sorted_stable_ord()
+                    .iter()
+                    .map(|s| format!("+{}", s.as_str())),
+                ),
+                _ => all_rust_features.push(feature.to_string()),
+            }
+        }
+
+        let feats = all_rust_features
+            .iter()
+            .filter_map(|s| {
+                let enable_disable = match s.chars().next() {
+                    None => return None,
+                    Some(c @ ('+' | '-')) => c,
+                    Some(_) => {
+                        if diagnostics {
+                            sess.dcx().emit_warn(UnknownCTargetFeaturePrefix { feature: s });
+                        }
+                        return None;
                     }
+                };
+
+                let feature = backend_feature_name(sess, s)?;
+                // Warn against use of LLVM specific feature names and unstable features on the CLI.
+                if diagnostics {
+                    let feature_state = supported_features.iter().find(|&&(v, _, _)| v == feature);
+                    if feature_state.is_none() {
+                        let rust_feature =
+                            supported_features.iter().find_map(|&(rust_feature, _, _)| {
+                                let llvm_features = to_llvm_features(sess, rust_feature);
+                                if llvm_features.contains(feature)
+                                    && !llvm_features.contains(rust_feature)
+                                {
+                                    Some(rust_feature)
+                                } else {
+                                    None
+                                }
+                            });
+                        let unknown_feature = if let Some(rust_feature) = rust_feature {
+                            UnknownCTargetFeature {
+                                feature,
+                                rust_feature: PossibleFeature::Some { rust_feature },
+                            }
+                        } else {
+                            UnknownCTargetFeature { feature, rust_feature: PossibleFeature::None }
+                        };
+                        sess.dcx().emit_warn(unknown_feature);
+                    } else if feature_state
+                        .is_some_and(|(_name, feature_gate, _implied)| !feature_gate.is_stable())
+                    {
+                        // An unstable feature. Warn about using it.
+                        sess.dcx().emit_warn(UnstableCTargetFeature { feature });
+                    }
+                }
+
+                if diagnostics {
+                    // FIXME(nagisa): figure out how to not allocate a full hashset here.
+                    featsmap.insert(feature, enable_disable == '+');
+                }
+
+                // rustc-specific features do not get passed down to LLVM…
+                if RUSTC_SPECIFIC_FEATURES.contains(&feature) {
                     return None;
                 }
-            };
 
-            let feature = backend_feature_name(sess, s)?;
-            // Warn against use of LLVM specific feature names and unstable features on the CLI.
-            if diagnostics {
-                let feature_state = supported_features.iter().find(|&&(v, _)| v == feature);
-                if feature_state.is_none() {
-                    let rust_feature = supported_features.iter().find_map(|&(rust_feature, _)| {
-                        let llvm_features = to_llvm_features(sess, rust_feature);
-                        if llvm_features.contains(feature) && !llvm_features.contains(rust_feature)
-                        {
-                            Some(rust_feature)
-                        } else {
-                            None
-                        }
-                    });
-                    let unknown_feature = if let Some(rust_feature) = rust_feature {
-                        UnknownCTargetFeature {
-                            feature,
-                            rust_feature: PossibleFeature::Some { rust_feature },
-                        }
-                    } else {
-                        UnknownCTargetFeature { feature, rust_feature: PossibleFeature::None }
-                    };
-                    sess.dcx().emit_warn(unknown_feature);
-                } else if feature_state
-                    .is_some_and(|(_name, feature_gate)| !feature_gate.is_stable())
-                {
-                    // An unstable feature. Warn about using it.
-                    sess.dcx().emit_warn(UnstableCTargetFeature { feature });
+                // if the target-feature is "backchain" and LLVM version is greater than 18
+                // then we also need to add "+backchain" to the target-features attribute.
+                // otherwise, we will only add the naked `backchain` attribute to the attribute-group.
+                if feature == "backchain" && llvm_major < 18 {
+                    return None;
                 }
-            }
+                // ... otherwise though we run through `to_llvm_features` when
+                // passing requests down to LLVM. This means that all in-language
+                // features also work on the command line instead of having two
+                // different names when the LLVM name and the Rust name differ.
+                let llvm_feature = to_llvm_features(sess, feature);
 
-            if diagnostics {
-                // FIXME(nagisa): figure out how to not allocate a full hashset here.
-                featsmap.insert(feature, enable_disable == '+');
-            }
-
-            // rustc-specific features do not get passed down to LLVM…
-            if RUSTC_SPECIFIC_FEATURES.contains(&feature) {
-                return None;
-            }
-
-            // if the target-feature is "backchain" and LLVM version is greater than 18
-            // then we also need to add "+backchain" to the target-features attribute.
-            // otherwise, we will only add the naked `backchain` attribute to the attribute-group.
-            if feature == "backchain" && llvm_major < 18 {
-                return None;
-            }
-            // ... otherwise though we run through `to_llvm_features` when
-            // passing requests down to LLVM. This means that all in-language
-            // features also work on the command line instead of having two
-            // different names when the LLVM name and the Rust name differ.
-            let llvm_feature = to_llvm_features(sess, feature);
-
-            Some(
-                std::iter::once(format!("{}{}", enable_disable, llvm_feature.llvm_feature_name))
-                    .chain(llvm_feature.dependency.into_iter().filter_map(move |feat| {
-                        match (enable_disable, feat) {
+                Some(
+                    std::iter::once(format!(
+                        "{}{}",
+                        enable_disable, llvm_feature.llvm_feature_name
+                    ))
+                    .chain(llvm_feature.dependency.into_iter().filter_map(
+                        move |feat| match (enable_disable, feat) {
                             ('-' | '+', TargetFeatureFoldStrength::Both(f))
                             | ('+', TargetFeatureFoldStrength::EnableOnly(f)) => {
                                 Some(format!("{enable_disable}{f}"))
                             }
                             _ => None,
-                        }
-                    })),
-            )
-        })
-        .flatten();
-    features.extend(feats);
+                        },
+                    )),
+                )
+            })
+            .flatten();
+        features.extend(feats);
+
+        if diagnostics && let Some(f) = check_tied_features(sess, &featsmap) {
+            sess.dcx().emit_err(TargetFeatureDisableOrEnable {
+                features: f,
+                span: None,
+                missing_features: None,
+            });
+        }
+    }
 
     // -Zfixed-x18
     if sess.opts.unstable_opts.fixed_x18 {
@@ -646,30 +680,6 @@ pub(crate) fn global_llvm_features(sess: &Session, diagnostics: bool) -> Vec<Str
         }
     }
 
-    // This is a workaround for a LLVM bug that doesn't implicitly enable
-    // `simd128` when `relaxed-simd` is.
-    // See <https://github.com/llvm/llvm-project/pull/99803>, which didn't make
-    // it into a released version of LLVM yet.
-    //
-    // This doesn't use the "implicit target feature" system because it is only
-    // used for function attributes in other targets, which fixes this bug as
-    // well on the function attribute level.
-    if sess.target.families.contains(&"wasm".into()) {
-        if features.iter().any(|f| f == "+relaxed-simd")
-            && !features.iter().any(|f| f == "+simd128")
-        {
-            features.push("+simd128".into());
-        }
-    }
-
-    if diagnostics && let Some(f) = check_tied_features(sess, &featsmap) {
-        sess.dcx().emit_err(TargetFeatureDisableOrEnable {
-            features: f,
-            span: None,
-            missing_features: None,
-        });
-    }
-
     features
 }
 

compiler/rustc_codegen_llvm/src/mono_item.rs

@@ -12,7 +12,7 @@ use tracing::debug;
 use crate::context::CodegenCx;
 use crate::errors::SymbolAlreadyDefined;
 use crate::type_of::LayoutLlvmExt;
-use crate::{attributes, base, llvm};
+use crate::{base, llvm};
 
 impl<'tcx> PreDefineMethods<'tcx> for CodegenCx<'_, 'tcx> {
     fn predefine_static(
@@ -87,8 +87,6 @@ impl<'tcx> PreDefineMethods<'tcx> for CodegenCx<'_, 'tcx> {
 
         debug!("predefine_fn: instance = {:?}", instance);
 
-        attributes::from_fn_attrs(self, lldecl, instance);
-
         unsafe {
             if self.should_assume_dso_local(lldecl, false) {
                 llvm::LLVMRustSetDSOLocal(lldecl, true);

compiler/rustc_codegen_ssa/src/back/metadata.rs

@@ -208,6 +208,7 @@ pub(crate) fn create_object_file(sess: &Session) -> Option<write::Object<'static
         "powerpc64" => (Architecture::PowerPc64, None),
         "riscv32" => (Architecture::Riscv32, None),
         "riscv64" => (Architecture::Riscv64, None),
+        "sparc" => (Architecture::Sparc32Plus, None),
         "sparc64" => (Architecture::Sparc64, None),
         "avr" => (Architecture::Avr, None),
         "msp430" => (Architecture::Msp430, None),

compiler/rustc_codegen_ssa/src/target_features.rs

@@ -1,11 +1,12 @@
 use rustc_ast::ast;
 use rustc_attr::InstructionSetAttr;
 use rustc_data_structures::fx::FxIndexSet;
-use rustc_data_structures::unord::UnordMap;
+use rustc_data_structures::unord::{UnordMap, UnordSet};
 use rustc_errors::Applicability;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LocalDefId, LOCAL_CRATE};
 use rustc_middle::bug;
+use rustc_middle::middle::codegen_fn_attrs::TargetFeature;
 use rustc_middle::query::Providers;
 use rustc_middle::ty::TyCtxt;
 use rustc_session::parse::feature_err;
@@ -18,7 +19,7 @@ pub fn from_target_feature(
     tcx: TyCtxt<'_>,
     attr: &ast::Attribute,
     supported_target_features: &UnordMap<String, Option<Symbol>>,
-    target_features: &mut Vec<Symbol>,
+    target_features: &mut Vec<TargetFeature>,
 ) {
     let Some(list) = attr.meta_item_list() else { return };
     let bad_item = |span| {
@@ -30,6 +31,7 @@ pub fn from_target_feature(
             .emit();
     };
     let rust_features = tcx.features();
+    let mut added_target_features = Vec::new();
     for item in list {
         // Only `enable = ...` is accepted in the meta-item list.
         if !item.has_name(sym::enable) {
@@ -44,7 +46,7 @@ pub fn from_target_feature(
         };
 
         // We allow comma separation to enable multiple features.
-        target_features.extend(value.as_str().split(',').filter_map(|feature| {
+        added_target_features.extend(value.as_str().split(',').filter_map(|feature| {
             let Some(feature_gate) = supported_target_features.get(feature) else {
                 let msg = format!("the feature named `{feature}` is not valid for this target");
                 let mut err = tcx.dcx().struct_span_err(item.span(), msg);
@@ -98,13 +100,26 @@ pub fn from_target_feature(
         }));
     }
 
-    for (feature, requires) in tcx.sess.target.implicit_target_features() {
-        if target_features.iter().any(|f| f.as_str() == *feature)
-            && !target_features.iter().any(|f| f.as_str() == *requires)
-        {
-            target_features.push(Symbol::intern(requires));
-        }
+    // Add explicit features
+    target_features.extend(
+        added_target_features.iter().copied().map(|name| TargetFeature { name, implied: false }),
+    );
+
+    // Add implied features
+    let mut implied_target_features = UnordSet::new();
+    for feature in added_target_features.iter() {
+        implied_target_features.extend(tcx.implied_target_features(*feature).clone());
     }
+    for feature in added_target_features.iter() {
+        implied_target_features.remove(feature);
+    }
+    target_features.extend(
+        implied_target_features
+            .into_sorted_stable_ord()
+            .iter()
+            .copied()
+            .map(|name| TargetFeature { name, implied: true }),
+    )
 }
 
 /// Computes the set of target features used in a function for the purposes of
@@ -113,7 +128,7 @@ fn asm_target_features(tcx: TyCtxt<'_>, did: DefId) -> &FxIndexSet<Symbol> {
     let mut target_features = tcx.sess.unstable_target_features.clone();
     if tcx.def_kind(did).has_codegen_attrs() {
         let attrs = tcx.codegen_fn_attrs(did);
-        target_features.extend(&attrs.target_features);
+        target_features.extend(attrs.target_features.iter().map(|feature| feature.name));
         match attrs.instruction_set {
             None => {}
             Some(InstructionSetAttr::ArmA32) => {
@@ -158,10 +173,14 @@ pub(crate) fn provide(providers: &mut Providers) {
                     .target
                     .supported_target_features()
                     .iter()
-                    .map(|&(a, b)| (a.to_string(), b.as_feature_name()))
+                    .map(|&(a, b, _)| (a.to_string(), b.as_feature_name()))
                     .collect()
             }
         },
+        implied_target_features: |tcx, feature| {
+            UnordSet::from(tcx.sess.target.implied_target_features(std::iter::once(feature)))
+                .into_sorted_stable_ord()
+        },
         asm_target_features,
         ..*providers
     }

compiler/rustc_const_eval/src/interpret/call.rs

@@ -317,19 +317,20 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             && attrs
                 .target_features
                 .iter()
-                .any(|feature| !self.tcx.sess.target_features.contains(feature))
+                .any(|feature| !self.tcx.sess.target_features.contains(&feature.name))
         {
             throw_ub_custom!(
                 fluent::const_eval_unavailable_target_features_for_fn,
                 unavailable_feats = attrs
                     .target_features
                     .iter()
-                    .filter(|&feature| !self.tcx.sess.target_features.contains(feature))
+                    .filter(|&feature| !feature.implied
+                        && !self.tcx.sess.target_features.contains(&feature.name))
                     .fold(String::new(), |mut s, feature| {
                         if !s.is_empty() {
                             s.push_str(", ");
                         }
-                        s.push_str(feature.as_str());
+                        s.push_str(feature.name.as_str());
                         s
                     }),
             );

compiler/rustc_lint/src/unused.rs

@@ -675,6 +675,13 @@ trait UnusedDelimLint {
             return true;
         }
 
+        // Do not lint against parentheses around `&raw [const|mut] expr`.
+        // These parentheses will have to be added e.g. when calling a method on the result of this
+        // expression, and we want to avoid churn wrt adding and removing parentheses.
+        if matches!(inner.kind, ast::ExprKind::AddrOf(ast::BorrowKind::Raw, ..)) {
+            return true;
+        }
+
         // Check if LHS needs parens to prevent false-positives in cases like
         // `fn x() -> u8 { ({ 0 } + 1) }`.
         //

compiler/rustc_middle/src/middle/codegen_fn_attrs.rs

@@ -28,7 +28,7 @@ pub struct CodegenFnAttrs {
     pub link_ordinal: Option<u16>,
     /// The `#[target_feature(enable = "...")]` attribute and the enabled
     /// features (only enabled features are supported right now).
-    pub target_features: Vec<Symbol>,
+    pub target_features: Vec<TargetFeature>,
     /// The `#[linkage = "..."]` attribute on Rust-defined items and the value we found.
     pub linkage: Option<Linkage>,
     /// The `#[linkage = "..."]` attribute on foreign items and the value we found.
@@ -51,6 +51,15 @@ pub struct CodegenFnAttrs {
     pub patchable_function_entry: Option<PatchableFunctionEntry>,
 }
 
+#[derive(Copy, Clone, Debug, TyEncodable, TyDecodable, HashStable)]
+pub struct TargetFeature {
+    /// The name of the target feature (e.g. "avx")
+    pub name: Symbol,
+    /// The feature is implied by another feature, rather than explicitly added by the
+    /// `#[target_feature]` attribute
+    pub implied: bool,
+}
+
 #[derive(Copy, Clone, Debug, TyEncodable, TyDecodable, HashStable)]
 pub struct PatchableFunctionEntry {
     /// Nops to prepend to the function

compiler/rustc_middle/src/query/mod.rs

@@ -2183,6 +2183,12 @@ rustc_queries! {
         desc { "looking up supported target features" }
     }
 
+    query implied_target_features(feature: Symbol) -> &'tcx Vec<Symbol> {
+        arena_cache
+        eval_always
+        desc { "looking up implied target features" }
+    }
+
     query features_query(_: ()) -> &'tcx rustc_feature::Features {
         feedable
         desc { "looking up enabled feature gates" }

compiler/rustc_mir_build/src/check_unsafety.rs

@@ -5,6 +5,7 @@ use std::ops::Bound;
 use rustc_errors::DiagArgValue;
 use rustc_hir::def::DefKind;
 use rustc_hir::{self as hir, BindingMode, ByRef, HirId, Mutability};
+use rustc_middle::middle::codegen_fn_attrs::TargetFeature;
 use rustc_middle::mir::BorrowKind;
 use rustc_middle::span_bug;
 use rustc_middle::thir::visit::Visitor;
@@ -31,7 +32,7 @@ struct UnsafetyVisitor<'a, 'tcx> {
     safety_context: SafetyContext,
     /// The `#[target_feature]` attributes of the body. Used for checking
     /// calls to functions with `#[target_feature]` (RFC 2396).
-    body_target_features: &'tcx [Symbol],
+    body_target_features: &'tcx [TargetFeature],
     /// When inside the LHS of an assignment to a field, this is the type
     /// of the LHS and the span of the assignment expression.
     assignment_info: Option<Ty<'tcx>>,
@@ -442,14 +443,21 @@ impl<'a, 'tcx> Visitor<'a, 'tcx> for UnsafetyVisitor<'a, 'tcx> {
                     // is_like_wasm check in hir_analysis/src/collect.rs
                     let callee_features = &self.tcx.codegen_fn_attrs(func_did).target_features;
                     if !self.tcx.sess.target.options.is_like_wasm
-                        && !callee_features
-                            .iter()
-                            .all(|feature| self.body_target_features.contains(feature))
+                        && !callee_features.iter().all(|feature| {
+                            self.body_target_features.iter().any(|f| f.name == feature.name)
+                        })
                     {
                         let missing: Vec<_> = callee_features
                             .iter()
                             .copied()
-                            .filter(|feature| !self.body_target_features.contains(feature))
+                            .filter(|feature| {
+                                !feature.implied
+                                    && !self
+                                        .body_target_features
+                                        .iter()
+                                        .any(|body_feature| body_feature.name == feature.name)
+                            })
+                            .map(|feature| feature.name)
                             .collect();
                         let build_enabled = self
                             .tcx

compiler/rustc_mir_transform/src/inline.rs

@@ -479,7 +479,9 @@ impl<'tcx> Inliner<'tcx> {
             return Err("incompatible instruction set");
         }
 
-        if callee_attrs.target_features != self.codegen_fn_attrs.target_features {
+        let callee_feature_names = callee_attrs.target_features.iter().map(|f| f.name);
+        let this_feature_names = self.codegen_fn_attrs.target_features.iter().map(|f| f.name);
+        if callee_feature_names.ne(this_feature_names) {
             // In general it is not correct to inline a callee with target features that are a
             // subset of the caller. This is because the callee might contain calls, and the ABI of
             // those calls depends on the target features of the surrounding function. By moving a

compiler/rustc_resolve/src/build_reduced_graph.rs

@@ -283,6 +283,7 @@ impl<'a, 'b, 'tcx> BuildReducedGraphVisitor<'a, 'b, 'tcx> {
                     parent_scope,
                     finalize.then(|| Finalize::new(id, path.span)),
                     None,
+                    None,
                 ) {
                     PathResult::Module(ModuleOrUniformRoot::Module(module)) => {
                         let res = module.res().expect("visibility resolved to unnamed block");
@@ -372,7 +373,7 @@ impl<'a, 'b, 'tcx> BuildReducedGraphVisitor<'a, 'b, 'tcx> {
             has_attributes: !item.attrs.is_empty(),
             root_span,
             root_id,
-            vis: Cell::new(Some(vis)),
+            vis,
             used: Default::default(),
         });
 
@@ -888,7 +889,7 @@ impl<'a, 'b, 'tcx> BuildReducedGraphVisitor<'a, 'b, 'tcx> {
             root_span: item.span,
             span: item.span,
             module_path: Vec::new(),
-            vis: Cell::new(Some(vis)),
+            vis,
             used: Cell::new(used.then_some(Used::Other)),
         });
         self.r.potentially_unused_imports.push(import);
@@ -1089,7 +1090,7 @@ impl<'a, 'b, 'tcx> BuildReducedGraphVisitor<'a, 'b, 'tcx> {
                 root_span: span,
                 span,
                 module_path: Vec::new(),
-                vis: Cell::new(Some(ty::Visibility::Restricted(CRATE_DEF_ID))),
+                vis: ty::Visibility::Restricted(CRATE_DEF_ID),
                 used: Default::default(),
             })
         };
@@ -1125,6 +1126,7 @@ impl<'a, 'b, 'tcx> BuildReducedGraphVisitor<'a, 'b, 'tcx> {
                     ident,
                     MacroNS,
                     &self.parent_scope,
+                    None,
                 );
                 if let Ok(binding) = result {
                     let import = macro_use_import(self, ident.span, false);
@@ -1253,7 +1255,7 @@ impl<'a, 'b, 'tcx> BuildReducedGraphVisitor<'a, 'b, 'tcx> {
                     root_span: span,
                     span,
                     module_path: Vec::new(),
-                    vis: Cell::new(Some(vis)),
+                    vis,
                     used: Cell::new(Some(Used::Other)),
                 });
                 let import_binding = self.r.import(binding, import);

compiler/rustc_resolve/src/check_unused.rs

@@ -382,7 +382,7 @@ impl Resolver<'_, '_> {
         for import in self.potentially_unused_imports.iter() {
             match import.kind {
                 _ if import.used.get().is_some()
-                    || import.expect_vis().is_public()
+                    || import.vis.is_public()
                     || import.span.is_dummy() =>
                 {
                     if let ImportKind::MacroUse { .. } = import.kind {

compiler/rustc_resolve/src/diagnostics.rs

@@ -1052,6 +1052,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                                 parent_scope,
                                 false,
                                 false,
+                                None,
                             ) {
                                 suggestions.extend(
                                     ext.helper_attrs
@@ -1506,6 +1507,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                 None,
                 false,
                 None,
+                None,
             ) {
                 let desc = match binding.res() {
                     Res::Def(DefKind::Macro(MacroKind::Bang), _) => {
@@ -1983,6 +1985,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         parent_scope: &ParentScope<'a>,
         ribs: Option<&PerNS<Vec<Rib<'a>>>>,
         ignore_binding: Option<NameBinding<'a>>,
+        ignore_import: Option<Import<'a>>,
         module: Option<ModuleOrUniformRoot<'a>>,
         failed_segment_idx: usize,
         ident: Ident,
@@ -2066,11 +2069,13 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                         parent_scope,
                         None,
                         ignore_binding,
+                        ignore_import,
                     )
                     .ok()
                 } else if let Some(ribs) = ribs
                     && let Some(TypeNS | ValueNS) = opt_ns
                 {
+                    assert!(ignore_import.is_none());
                     match self.resolve_ident_in_lexical_scope(
                         ident,
                         ns_to_try,
@@ -2091,6 +2096,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                         None,
                         false,
                         ignore_binding,
+                        ignore_import,
                     )
                     .ok()
                 };
@@ -2132,6 +2138,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         } else if ident.name.as_str().chars().next().is_some_and(|c| c.is_ascii_uppercase()) {
             // Check whether the name refers to an item in the value namespace.
             let binding = if let Some(ribs) = ribs {
+                assert!(ignore_import.is_none());
                 self.resolve_ident_in_lexical_scope(
                     ident,
                     ValueNS,
@@ -2206,6 +2213,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                 None,
                 false,
                 ignore_binding,
+                ignore_import,
             ) {
                 let descr = binding.res().descr();
                 (format!("{descr} `{ident}` is not a crate or module"), suggestion)
@@ -2259,7 +2267,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
     ) -> Option<(Vec<Segment>, Option<String>)> {
         // Replace first ident with `self` and check if that is valid.
         path[0].ident.name = kw::SelfLower;
-        let result = self.maybe_resolve_path(&path, None, parent_scope);
+        let result = self.maybe_resolve_path(&path, None, parent_scope, None);
         debug!("make_missing_self_suggestion: path={:?} result={:?}", path, result);
         if let PathResult::Module(..) = result { Some((path, None)) } else { None }
     }
@@ -2278,7 +2286,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
     ) -> Option<(Vec<Segment>, Option<String>)> {
         // Replace first ident with `crate` and check if that is valid.
         path[0].ident.name = kw::Crate;
-        let result = self.maybe_resolve_path(&path, None, parent_scope);
+        let result = self.maybe_resolve_path(&path, None, parent_scope, None);
         debug!("make_missing_crate_suggestion:  path={:?} result={:?}", path, result);
         if let PathResult::Module(..) = result {
             Some((
@@ -2309,7 +2317,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
     ) -> Option<(Vec<Segment>, Option<String>)> {
         // Replace first ident with `crate` and check if that is valid.
         path[0].ident.name = kw::Super;
-        let result = self.maybe_resolve_path(&path, None, parent_scope);
+        let result = self.maybe_resolve_path(&path, None, parent_scope, None);
         debug!("make_missing_super_suggestion:  path={:?} result={:?}", path, result);
         if let PathResult::Module(..) = result { Some((path, None)) } else { None }
     }
@@ -2343,7 +2351,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         for name in extern_crate_names.into_iter() {
             // Replace first ident with a crate name and check if that is valid.
             path[0].ident.name = name;
-            let result = self.maybe_resolve_path(&path, None, parent_scope);
+            let result = self.maybe_resolve_path(&path, None, parent_scope, None);
             debug!(
                 "make_external_crate_suggestion: name={:?} path={:?} result={:?}",
                 name, path, result
@@ -2509,12 +2517,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
     }
 
     /// Finds a cfg-ed out item inside `module` with the matching name.
-    pub(crate) fn find_cfg_stripped(
-        &mut self,
-        err: &mut Diag<'_>,
-        segment: &Symbol,
-        module: DefId,
-    ) {
+    pub(crate) fn find_cfg_stripped(&self, err: &mut Diag<'_>, segment: &Symbol, module: DefId) {
         let local_items;
         let symbols = if module.is_local() {
             local_items = self

compiler/rustc_resolve/src/ident.rs

@@ -14,6 +14,7 @@ use Determinacy::*;
 use Namespace::*;
 
 use crate::errors::{ParamKindInEnumDiscriminant, ParamKindInNonTrivialAnonConst};
+use crate::imports::Import;
 use crate::late::{ConstantHasGenerics, NoConstantGenericsReason, PathSource, Rib, RibKind};
 use crate::macros::{sub_namespace_match, MacroRulesScope};
 use crate::{
@@ -351,6 +352,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                 parent_scope,
                 finalize.map(|finalize| Finalize { used: Used::Scope, ..finalize }),
                 ignore_binding,
+                None,
             );
             if let Ok(binding) = item {
                 // The ident resolves to an item.
@@ -364,6 +366,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             finalize,
             finalize.is_some(),
             ignore_binding,
+            None,
         )
         .ok()
         .map(LexicalScopeBinding::Item)
@@ -383,6 +386,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         finalize: Option<Finalize>,
         force: bool,
         ignore_binding: Option<NameBinding<'a>>,
+        ignore_import: Option<Import<'a>>,
     ) -> Result<NameBinding<'a>, Determinacy> {
         bitflags::bitflags! {
             #[derive(Clone, Copy)]
@@ -455,6 +459,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                                 parent_scope,
                                 true,
                                 force,
+                                ignore_import,
                             ) {
                                 Ok((Some(ext), _)) => {
                                     if ext.helper_attrs.contains(&ident.name) {
@@ -496,6 +501,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                             parent_scope,
                             finalize,
                             ignore_binding,
+                            ignore_import,
                         );
                         match binding {
                             Ok(binding) => Ok((binding, Flags::MODULE | Flags::MISC_SUGGEST_CRATE)),
@@ -518,6 +524,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                             !matches!(scope_set, ScopeSet::Late(..)),
                             finalize.map(|finalize| Finalize { used: Used::Scope, ..finalize }),
                             ignore_binding,
+                            ignore_import,
                         );
                         match binding {
                             Ok(binding) => {
@@ -585,6 +592,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                                 parent_scope,
                                 None,
                                 ignore_binding,
+                                ignore_import,
                             ) {
                                 if matches!(use_prelude, UsePrelude::Yes)
                                     || this.is_builtin_macro(binding.res())
@@ -738,8 +746,9 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         ident: Ident,
         ns: Namespace,
         parent_scope: &ParentScope<'a>,
+        ignore_import: Option<Import<'a>>,
     ) -> Result<NameBinding<'a>, Determinacy> {
-        self.resolve_ident_in_module_ext(module, ident, ns, parent_scope, None, None)
+        self.resolve_ident_in_module_ext(module, ident, ns, parent_scope, None, None, ignore_import)
             .map_err(|(determinacy, _)| determinacy)
     }
 
@@ -752,9 +761,18 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         parent_scope: &ParentScope<'a>,
         finalize: Option<Finalize>,
         ignore_binding: Option<NameBinding<'a>>,
+        ignore_import: Option<Import<'a>>,
     ) -> Result<NameBinding<'a>, Determinacy> {
-        self.resolve_ident_in_module_ext(module, ident, ns, parent_scope, finalize, ignore_binding)
-            .map_err(|(determinacy, _)| determinacy)
+        self.resolve_ident_in_module_ext(
+            module,
+            ident,
+            ns,
+            parent_scope,
+            finalize,
+            ignore_binding,
+            ignore_import,
+        )
+        .map_err(|(determinacy, _)| determinacy)
     }
 
     #[instrument(level = "debug", skip(self))]
@@ -766,6 +784,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         parent_scope: &ParentScope<'a>,
         finalize: Option<Finalize>,
         ignore_binding: Option<NameBinding<'a>>,
+        ignore_import: Option<Import<'a>>,
     ) -> Result<NameBinding<'a>, (Determinacy, Weak)> {
         let tmp_parent_scope;
         let mut adjusted_parent_scope = parent_scope;
@@ -792,6 +811,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             false,
             finalize,
             ignore_binding,
+            ignore_import,
         )
     }
 
@@ -804,6 +824,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         parent_scope: &ParentScope<'a>,
         finalize: Option<Finalize>,
         ignore_binding: Option<NameBinding<'a>>,
+        ignore_import: Option<Import<'a>>,
     ) -> Result<NameBinding<'a>, Determinacy> {
         self.resolve_ident_in_module_unadjusted_ext(
             module,
@@ -813,6 +834,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             false,
             finalize,
             ignore_binding,
+            ignore_import,
         )
         .map_err(|(determinacy, _)| determinacy)
     }
@@ -831,6 +853,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         // This binding should be ignored during in-module resolution, so that we don't get
         // "self-confirming" import resolutions during import validation and checking.
         ignore_binding: Option<NameBinding<'a>>,
+        ignore_import: Option<Import<'a>>,
     ) -> Result<NameBinding<'a>, (Determinacy, Weak)> {
         let module = match module {
             ModuleOrUniformRoot::Module(module) => module,
@@ -843,6 +866,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                     finalize,
                     finalize.is_some(),
                     ignore_binding,
+                    ignore_import,
                 );
                 return binding.map_err(|determinacy| (determinacy, Weak::No));
             }
@@ -879,6 +903,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                     finalize,
                     finalize.is_some(),
                     ignore_binding,
+                    ignore_import,
                 );
                 return binding.map_err(|determinacy| (determinacy, Weak::No));
             }
@@ -962,25 +987,23 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         // Check if one of single imports can still define the name,
         // if it can then our result is not determined and can be invalidated.
         for single_import in &resolution.single_imports {
-            let Some(import_vis) = single_import.vis.get() else {
-                // This branch handles a cycle in single imports, which occurs
-                // when we've previously **steal** the `vis` value during an import
-                // process.
+            if ignore_import == Some(*single_import) {
+                // This branch handles a cycle in single imports.
                 //
                 // For example:
                 // ```
                 // use a::b;
                 // use b as a;
                 // ```
-                // 1. Steal the `vis` in `use a::b` and attempt to locate `a` in the
+                // 1. Record `use a::b` as the `ignore_import` and attempt to locate `a` in the
                 //    current module.
                 // 2. Encounter the import `use b as a`, which is a `single_import` for `a`,
                 //    and try to find `b` in the current module.
                 // 3. Re-encounter the `use a::b` import since it's a `single_import` of `b`.
                 //    This leads to entering this branch.
                 continue;
-            };
-            if !self.is_accessible_from(import_vis, parent_scope.module) {
+            }
+            if !self.is_accessible_from(single_import.vis, parent_scope.module) {
                 continue;
             }
             if let Some(ignored) = ignore_binding
@@ -1022,6 +1045,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                 &single_import.parent_scope,
                 None,
                 ignore_binding,
+                ignore_import,
             ) {
                 Err(Determined) => continue,
                 Ok(binding)
@@ -1070,10 +1094,10 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         // Check if one of glob imports can still define the name,
         // if it can then our "no resolution" result is not determined and can be invalidated.
         for glob_import in module.globs.borrow().iter() {
-            let Some(import_vis) = glob_import.vis.get() else {
+            if ignore_import == Some(*glob_import) {
                 continue;
-            };
-            if !self.is_accessible_from(import_vis, parent_scope.module) {
+            }
+            if !self.is_accessible_from(glob_import.vis, parent_scope.module) {
                 continue;
             }
             let module = match glob_import.imported_module.get() {
@@ -1100,6 +1124,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                 adjusted_parent_scope,
                 None,
                 ignore_binding,
+                ignore_import,
             );
 
             match result {
@@ -1412,8 +1437,9 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         path: &[Segment],
         opt_ns: Option<Namespace>, // `None` indicates a module path in import
         parent_scope: &ParentScope<'a>,
+        ignore_import: Option<Import<'a>>,
     ) -> PathResult<'a> {
-        self.resolve_path_with_ribs(path, opt_ns, parent_scope, None, None, None)
+        self.resolve_path_with_ribs(path, opt_ns, parent_scope, None, None, None, ignore_import)
     }
 
     #[instrument(level = "debug", skip(self))]
@@ -1424,8 +1450,17 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         parent_scope: &ParentScope<'a>,
         finalize: Option<Finalize>,
         ignore_binding: Option<NameBinding<'a>>,
+        ignore_import: Option<Import<'a>>,
     ) -> PathResult<'a> {
-        self.resolve_path_with_ribs(path, opt_ns, parent_scope, finalize, None, ignore_binding)
+        self.resolve_path_with_ribs(
+            path,
+            opt_ns,
+            parent_scope,
+            finalize,
+            None,
+            ignore_binding,
+            ignore_import,
+        )
     }
 
     pub(crate) fn resolve_path_with_ribs(
@@ -1436,6 +1471,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         finalize: Option<Finalize>,
         ribs: Option<&PerNS<Vec<Rib<'a>>>>,
         ignore_binding: Option<NameBinding<'a>>,
+        ignore_import: Option<Import<'a>>,
     ) -> PathResult<'a> {
         let mut module = None;
         let mut allow_super = true;
@@ -1538,10 +1574,12 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                     parent_scope,
                     finalize,
                     ignore_binding,
+                    ignore_import,
                 )
             } else if let Some(ribs) = ribs
                 && let Some(TypeNS | ValueNS) = opt_ns
             {
+                assert!(ignore_import.is_none());
                 match self.resolve_ident_in_lexical_scope(
                     ident,
                     ns,
@@ -1570,6 +1608,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                     finalize,
                     finalize.is_some(),
                     ignore_binding,
+                    ignore_import,
                 )
             };
 
@@ -1644,6 +1683,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                             parent_scope,
                             ribs,
                             ignore_binding,
+                            ignore_import,
                             module,
                             segment_idx,
                             ident,

compiler/rustc_resolve/src/imports.rs

@@ -175,7 +175,7 @@ pub(crate) struct ImportData<'a> {
     pub module_path: Vec<Segment>,
     /// The resolution of `module_path`.
     pub imported_module: Cell<Option<ModuleOrUniformRoot<'a>>>,
-    pub vis: Cell<Option<ty::Visibility>>,
+    pub vis: ty::Visibility,
     pub used: Cell<Option<Used>>,
 }
 
@@ -195,10 +195,6 @@ impl<'a> ImportData<'a> {
         }
     }
 
-    pub(crate) fn expect_vis(&self) -> ty::Visibility {
-        self.vis.get().expect("encountered cleared import visibility")
-    }
-
     pub(crate) fn id(&self) -> Option<NodeId> {
         match self.kind {
             ImportKind::Single { id, .. }
@@ -267,7 +263,7 @@ fn pub_use_of_private_extern_crate_hack(
     match (&import.kind, &binding.kind) {
         (ImportKind::Single { .. }, NameBindingKind::Import { import: binding_import, .. })
             if let ImportKind::ExternCrate { id, .. } = binding_import.kind
-                && import.expect_vis().is_public() =>
+                && import.vis.is_public() =>
         {
             Some(id)
         }
@@ -279,7 +275,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
     /// Given a binding and an import that resolves to it,
     /// return the corresponding binding defined by the import.
     pub(crate) fn import(&self, binding: NameBinding<'a>, import: Import<'a>) -> NameBinding<'a> {
-        let import_vis = import.expect_vis().to_def_id();
+        let import_vis = import.vis.to_def_id();
         let vis = if binding.vis.is_at_least(import_vis, self.tcx)
             || pub_use_of_private_extern_crate_hack(import, binding).is_some()
         {
@@ -773,11 +769,12 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         let module = if let Some(module) = import.imported_module.get() {
             module
         } else {
-            // For better failure detection, pretend that the import will
-            // not define any names while resolving its module path.
-            let orig_vis = import.vis.take();
-            let path_res = self.maybe_resolve_path(&import.module_path, None, &import.parent_scope);
-            import.vis.set(orig_vis);
+            let path_res = self.maybe_resolve_path(
+                &import.module_path,
+                None,
+                &import.parent_scope,
+                Some(import),
+            );
 
             match path_res {
                 PathResult::Module(module) => module,
@@ -807,16 +804,13 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         self.per_ns(|this, ns| {
             if !type_ns_only || ns == TypeNS {
                 if let Err(Undetermined) = source_bindings[ns].get() {
-                    // For better failure detection, pretend that the import will
-                    // not define any names while resolving its module path.
-                    let orig_vis = import.vis.take();
                     let binding = this.maybe_resolve_ident_in_module(
                         module,
                         source,
                         ns,
                         &import.parent_scope,
+                        Some(import),
                     );
-                    import.vis.set(orig_vis);
                     source_bindings[ns].set(binding);
                 } else {
                     return;
@@ -855,7 +849,6 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
     /// Optionally returns an unresolved import error. This error is buffered and used to
     /// consolidate multiple unresolved import errors into a single diagnostic.
     fn finalize_import(&mut self, import: Import<'a>) -> Option<UnresolvedImportError> {
-        let orig_vis = import.vis.take();
         let ignore_binding = match &import.kind {
             ImportKind::Single { target_bindings, .. } => target_bindings[TypeNS].get(),
             _ => None,
@@ -874,11 +867,12 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             &import.parent_scope,
             Some(finalize),
             ignore_binding,
+            Some(import),
         );
 
         let no_ambiguity =
             ambiguity_errors_len(&self.ambiguity_errors) == prev_ambiguity_errors_len;
-        import.vis.set(orig_vis);
+
         let module = match path_res {
             PathResult::Module(module) => {
                 // Consistency checks, analogous to `finalize_macro_resolutions`.
@@ -1013,8 +1007,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                     }
                     if !is_prelude
                         && let Some(max_vis) = max_vis.get()
-                        && let import_vis = import.expect_vis()
-                        && !max_vis.is_at_least(import_vis, self.tcx)
+                        && !max_vis.is_at_least(import.vis, self.tcx)
                     {
                         let def_id = self.local_def_id(id);
                         self.lint_buffer.buffer_lint(
@@ -1023,7 +1016,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                             import.span,
                             BuiltinLintDiag::RedundantImportVisibility {
                                 max_vis: max_vis.to_string(def_id, self.tcx),
-                                import_vis: import_vis.to_string(def_id, self.tcx),
+                                import_vis: import.vis.to_string(def_id, self.tcx),
                                 span: import.span,
                             },
                         );
@@ -1038,9 +1031,14 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             // importing it if available.
             let mut path = import.module_path.clone();
             path.push(Segment::from_ident(ident));
-            if let PathResult::Module(ModuleOrUniformRoot::Module(module)) =
-                self.resolve_path(&path, None, &import.parent_scope, Some(finalize), ignore_binding)
-            {
+            if let PathResult::Module(ModuleOrUniformRoot::Module(module)) = self.resolve_path(
+                &path,
+                None,
+                &import.parent_scope,
+                Some(finalize),
+                ignore_binding,
+                None,
+            ) {
                 let res = module.res().map(|r| (r, ident));
                 for error in &mut self.privacy_errors[privacy_errors_len..] {
                     error.outermost_res = res;
@@ -1051,7 +1049,6 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         let mut all_ns_err = true;
         self.per_ns(|this, ns| {
             if !type_ns_only || ns == TypeNS {
-                let orig_vis = import.vis.take();
                 let binding = this.resolve_ident_in_module(
                     module,
                     ident,
@@ -1059,8 +1056,8 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                     &import.parent_scope,
                     Some(Finalize { report_private: false, ..finalize }),
                     target_bindings[ns].get(),
+                    Some(import),
                 );
-                import.vis.set(orig_vis);
 
                 match binding {
                     Ok(binding) => {
@@ -1123,6 +1120,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                         &import.parent_scope,
                         Some(finalize),
                         None,
+                        None,
                     );
                     if binding.is_ok() {
                         all_ns_failed = false;
@@ -1233,7 +1231,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         let mut crate_private_reexport = false;
         self.per_ns(|this, ns| {
             if let Ok(binding) = source_bindings[ns].get() {
-                if !binding.vis.is_at_least(import.expect_vis(), this.tcx) {
+                if !binding.vis.is_at_least(import.vis, this.tcx) {
                     reexport_error = Some((ns, binding));
                     if let ty::Visibility::Restricted(binding_def_id) = binding.vis {
                         if binding_def_id.is_top_level_module() {
@@ -1370,6 +1368,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                     None,
                     false,
                     target_bindings[ns].get(),
+                    None,
                 ) {
                     Ok(other_binding) => {
                         is_redundant = binding.res() == other_binding.res()

compiler/rustc_resolve/src/late.rs

@@ -1388,6 +1388,7 @@ impl<'a: 'ast, 'b, 'ast, 'tcx> LateResolutionVisitor<'a, 'b, 'ast, 'tcx> {
             finalize,
             Some(&self.ribs),
             None,
+            None,
         )
     }
 
@@ -4186,7 +4187,7 @@ impl<'a: 'ast, 'b, 'ast, 'tcx> LateResolutionVisitor<'a, 'b, 'ast, 'tcx> {
             let path_seg = |seg: &Segment| PathSegment::from_ident(seg.ident);
             let path = Path { segments: path.iter().map(path_seg).collect(), span, tokens: None };
             if let Ok((_, res)) =
-                self.r.resolve_macro_path(&path, None, &self.parent_scope, false, false)
+                self.r.resolve_macro_path(&path, None, &self.parent_scope, false, false, None)
             {
                 return Ok(Some(PartialRes::new(res)));
             }

compiler/rustc_resolve/src/late/diagnostics.rs

@@ -2058,6 +2058,7 @@ impl<'a: 'ast, 'ast, 'tcx> LateResolutionVisitor<'a, '_, 'ast, 'tcx> {
                 ident,
                 ns,
                 &self.parent_scope,
+                None,
             ) {
                 let res = binding.res();
                 if filter_fn(res) {

compiler/rustc_resolve/src/lib.rs

@@ -2120,7 +2120,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             }
         }
 
-        match self.maybe_resolve_path(&segments, Some(ns), &parent_scope) {
+        match self.maybe_resolve_path(&segments, Some(ns), &parent_scope, None) {
             PathResult::Module(ModuleOrUniformRoot::Module(module)) => Some(module.res().unwrap()),
             PathResult::NonModule(path_res) => path_res.full_res(),
             PathResult::Module(ModuleOrUniformRoot::ExternPrelude) | PathResult::Failed { .. } => {
@@ -2204,6 +2204,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             ident,
             ValueNS,
             parent_scope,
+            None,
         ) else {
             return;
         };

compiler/rustc_resolve/src/macros.rs

@@ -39,6 +39,7 @@ use crate::errors::{
     self, AddAsNonDerive, CannotDetermineMacroResolution, CannotFindIdentInThisScope,
     MacroExpectedFound, RemoveSurroundingDerive,
 };
+use crate::imports::Import;
 use crate::Namespace::*;
 use crate::{
     BindingKey, BuiltinMacroState, DeriveData, Determinacy, Finalize, MacroData, ModuleKind,
@@ -399,6 +400,7 @@ impl<'a, 'tcx> ResolverExpand for Resolver<'a, 'tcx> {
                         &parent_scope,
                         true,
                         force,
+                        None,
                     ) {
                         Ok((Some(ext), _)) => {
                             if !ext.helper_attrs.is_empty() {
@@ -551,6 +553,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             force,
             deleg_impl,
             invoc_in_mod_inert_attr.map(|def_id| (def_id, node_id)),
+            None,
         ) {
             Ok((Some(ext), res)) => (ext, res),
             Ok((None, res)) => (self.dummy_ext(kind), res),
@@ -704,8 +707,18 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         parent_scope: &ParentScope<'a>,
         trace: bool,
         force: bool,
+        ignore_import: Option<Import<'a>>,
     ) -> Result<(Option<Lrc<SyntaxExtension>>, Res), Determinacy> {
-        self.resolve_macro_or_delegation_path(path, kind, parent_scope, trace, force, None, None)
+        self.resolve_macro_or_delegation_path(
+            path,
+            kind,
+            parent_scope,
+            trace,
+            force,
+            None,
+            None,
+            ignore_import,
+        )
     }
 
     fn resolve_macro_or_delegation_path(
@@ -717,6 +730,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         force: bool,
         deleg_impl: Option<LocalDefId>,
         invoc_in_mod_inert_attr: Option<(LocalDefId, NodeId)>,
+        ignore_import: Option<Import<'a>>,
     ) -> Result<(Option<Lrc<SyntaxExtension>>, Res), Determinacy> {
         let path_span = ast_path.span;
         let mut path = Segment::from_path(ast_path);
@@ -733,7 +747,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
 
         let res = if deleg_impl.is_some() || path.len() > 1 {
             let ns = if deleg_impl.is_some() { TypeNS } else { MacroNS };
-            let res = match self.maybe_resolve_path(&path, Some(ns), parent_scope) {
+            let res = match self.maybe_resolve_path(&path, Some(ns), parent_scope, ignore_import) {
                 PathResult::NonModule(path_res) if let Some(res) = path_res.full_res() => Ok(res),
                 PathResult::Indeterminate if !force => return Err(Determinacy::Undetermined),
                 PathResult::NonModule(..)
@@ -768,6 +782,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                 None,
                 force,
                 None,
+                None,
             );
             if let Err(Determinacy::Undetermined) = binding {
                 return Err(Determinacy::Undetermined);
@@ -852,6 +867,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                 &parent_scope,
                 Some(Finalize::new(ast::CRATE_NODE_ID, path_span)),
                 None,
+                None,
             ) {
                 PathResult::NonModule(path_res) if let Some(res) = path_res.full_res() => {
                     check_consistency(self, &path, path_span, kind, initial_res, res)
@@ -871,7 +887,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                         if let PathResult::Failed { span, label, module, .. } = path_res {
                             // try to suggest if it's not a macro, maybe a function
                             if let PathResult::NonModule(partial_res) =
-                                self.maybe_resolve_path(&path, Some(ValueNS), &parent_scope)
+                                self.maybe_resolve_path(&path, Some(ValueNS), &parent_scope, None)
                                 && partial_res.unresolved_segments() == 0
                             {
                                 let sm = self.tcx.sess.source_map();
@@ -921,6 +937,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                 Some(Finalize::new(ast::CRATE_NODE_ID, ident.span)),
                 true,
                 None,
+                None,
             ) {
                 Ok(binding) => {
                     let initial_res = initial_binding.map(|initial_binding| {
@@ -966,6 +983,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                 Some(Finalize::new(ast::CRATE_NODE_ID, ident.span)),
                 true,
                 None,
+                None,
             );
         }
     }
@@ -1070,6 +1088,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                 None,
                 false,
                 None,
+                None,
             );
             if fallback_binding.ok().and_then(|b| b.res().opt_def_id()) != Some(def_id) {
                 self.tcx.sess.psess.buffer_lint(
@@ -1143,7 +1162,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
 
         let mut indeterminate = false;
         for ns in namespaces {
-            match self.maybe_resolve_path(path, Some(*ns), &parent_scope) {
+            match self.maybe_resolve_path(path, Some(*ns), &parent_scope, None) {
                 PathResult::Module(ModuleOrUniformRoot::Module(_)) => return Ok(true),
                 PathResult::NonModule(partial_res) if partial_res.unresolved_segments() == 0 => {
                     return Ok(true);

compiler/rustc_target/src/target_features.rs

@@ -1,3 +1,4 @@
+use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_span::symbol::{sym, Symbol};
 
 /// Features that control behaviour of rustc, rather than the codegen.
@@ -53,136 +54,154 @@ impl Stability {
 //
 // Stabilizing a target feature requires t-lang approval.
 
-const ARM_ALLOWED_FEATURES: &[(&str, Stability)] = &[
+type ImpliedFeatures = &'static [&'static str];
+
+const ARM_ALLOWED_FEATURES: &[(&str, Stability, ImpliedFeatures)] = &[
     // tidy-alphabetical-start
-    ("aclass", Unstable(sym::arm_target_feature)),
-    ("aes", Unstable(sym::arm_target_feature)),
-    ("crc", Unstable(sym::arm_target_feature)),
-    ("d32", Unstable(sym::arm_target_feature)),
-    ("dotprod", Unstable(sym::arm_target_feature)),
-    ("dsp", Unstable(sym::arm_target_feature)),
-    ("fp-armv8", Unstable(sym::arm_target_feature)),
-    ("i8mm", Unstable(sym::arm_target_feature)),
-    ("mclass", Unstable(sym::arm_target_feature)),
-    ("neon", Unstable(sym::arm_target_feature)),
-    ("rclass", Unstable(sym::arm_target_feature)),
-    ("sha2", Unstable(sym::arm_target_feature)),
+    ("aclass", Unstable(sym::arm_target_feature), &[]),
+    ("aes", Unstable(sym::arm_target_feature), &["neon"]),
+    ("crc", Unstable(sym::arm_target_feature), &[]),
+    ("d32", Unstable(sym::arm_target_feature), &[]),
+    ("dotprod", Unstable(sym::arm_target_feature), &["neon"]),
+    ("dsp", Unstable(sym::arm_target_feature), &[]),
+    ("fp-armv8", Unstable(sym::arm_target_feature), &["vfp4"]),
+    ("i8mm", Unstable(sym::arm_target_feature), &["neon"]),
+    ("mclass", Unstable(sym::arm_target_feature), &[]),
+    ("neon", Unstable(sym::arm_target_feature), &["vfp3"]),
+    ("rclass", Unstable(sym::arm_target_feature), &[]),
+    ("sha2", Unstable(sym::arm_target_feature), &["neon"]),
     // This is needed for inline assembly, but shouldn't be stabilized as-is
     // since it should be enabled per-function using #[instruction_set], not
     // #[target_feature].
-    ("thumb-mode", Unstable(sym::arm_target_feature)),
-    ("thumb2", Unstable(sym::arm_target_feature)),
-    ("trustzone", Unstable(sym::arm_target_feature)),
-    ("v5te", Unstable(sym::arm_target_feature)),
-    ("v6", Unstable(sym::arm_target_feature)),
-    ("v6k", Unstable(sym::arm_target_feature)),
-    ("v6t2", Unstable(sym::arm_target_feature)),
-    ("v7", Unstable(sym::arm_target_feature)),
-    ("v8", Unstable(sym::arm_target_feature)),
-    ("vfp2", Unstable(sym::arm_target_feature)),
-    ("vfp3", Unstable(sym::arm_target_feature)),
-    ("vfp4", Unstable(sym::arm_target_feature)),
-    ("virtualization", Unstable(sym::arm_target_feature)),
+    ("thumb-mode", Unstable(sym::arm_target_feature), &[]),
+    ("thumb2", Unstable(sym::arm_target_feature), &[]),
+    ("trustzone", Unstable(sym::arm_target_feature), &[]),
+    ("v5te", Unstable(sym::arm_target_feature), &[]),
+    ("v6", Unstable(sym::arm_target_feature), &["v5te"]),
+    ("v6k", Unstable(sym::arm_target_feature), &["v6"]),
+    ("v6t2", Unstable(sym::arm_target_feature), &["v6k", "thumb2"]),
+    ("v7", Unstable(sym::arm_target_feature), &["v6t2"]),
+    ("v8", Unstable(sym::arm_target_feature), &["v7"]),
+    ("vfp2", Unstable(sym::arm_target_feature), &[]),
+    ("vfp3", Unstable(sym::arm_target_feature), &["vfp2", "d32"]),
+    ("vfp4", Unstable(sym::arm_target_feature), &["vfp3"]),
+    ("virtualization", Unstable(sym::arm_target_feature), &[]),
     // tidy-alphabetical-end
 ];
 
-const AARCH64_ALLOWED_FEATURES: &[(&str, Stability)] = &[
+const AARCH64_ALLOWED_FEATURES: &[(&str, Stability, ImpliedFeatures)] = &[
     // tidy-alphabetical-start
     // FEAT_AES & FEAT_PMULL
-    ("aes", Stable),
+    ("aes", Stable, &["neon"]),
     // FEAT_BF16
-    ("bf16", Stable),
+    ("bf16", Stable, &[]),
     // FEAT_BTI
-    ("bti", Stable),
+    ("bti", Stable, &[]),
     // FEAT_CRC
-    ("crc", Stable),
+    ("crc", Stable, &[]),
     // FEAT_DIT
-    ("dit", Stable),
+    ("dit", Stable, &[]),
     // FEAT_DotProd
-    ("dotprod", Stable),
+    ("dotprod", Stable, &["neon"]),
     // FEAT_DPB
-    ("dpb", Stable),
+    ("dpb", Stable, &[]),
     // FEAT_DPB2
-    ("dpb2", Stable),
+    ("dpb2", Stable, &["dpb"]),
     // FEAT_F32MM
-    ("f32mm", Stable),
+    ("f32mm", Stable, &["sve"]),
     // FEAT_F64MM
-    ("f64mm", Stable),
+    ("f64mm", Stable, &["sve"]),
     // FEAT_FCMA
-    ("fcma", Stable),
+    ("fcma", Stable, &["neon"]),
     // FEAT_FHM
-    ("fhm", Stable),
+    ("fhm", Stable, &["fp16"]),
     // FEAT_FLAGM
-    ("flagm", Stable),
+    ("flagm", Stable, &[]),
     // FEAT_FP16
-    ("fp16", Stable),
+    // Rust ties FP and Neon: https://github.com/rust-lang/rust/pull/91608
+    ("fp16", Stable, &["neon"]),
     // FEAT_FRINTTS
-    ("frintts", Stable),
+    ("frintts", Stable, &[]),
     // FEAT_I8MM
-    ("i8mm", Stable),
+    ("i8mm", Stable, &[]),
     // FEAT_JSCVT
-    ("jsconv", Stable),
+    // Rust ties FP and Neon: https://github.com/rust-lang/rust/pull/91608
+    ("jsconv", Stable, &["neon"]),
     // FEAT_LOR
-    ("lor", Stable),
+    ("lor", Stable, &[]),
     // FEAT_LSE
-    ("lse", Stable),
+    ("lse", Stable, &[]),
     // FEAT_MTE & FEAT_MTE2
-    ("mte", Stable),
+    ("mte", Stable, &[]),
     // FEAT_AdvSimd & FEAT_FP
-    ("neon", Stable),
+    ("neon", Stable, &[]),
     // FEAT_PAUTH (address authentication)
-    ("paca", Stable),
+    ("paca", Stable, &[]),
     // FEAT_PAUTH (generic authentication)
-    ("pacg", Stable),
+    ("pacg", Stable, &[]),
     // FEAT_PAN
-    ("pan", Stable),
+    ("pan", Stable, &[]),
     // FEAT_PMUv3
-    ("pmuv3", Stable),
+    ("pmuv3", Stable, &[]),
     // FEAT_RAND
-    ("rand", Stable),
+    ("rand", Stable, &[]),
     // FEAT_RAS & FEAT_RASv1p1
-    ("ras", Stable),
+    ("ras", Stable, &[]),
     // FEAT_RCPC
-    ("rcpc", Stable),
+    ("rcpc", Stable, &[]),
     // FEAT_RCPC2
-    ("rcpc2", Stable),
+    ("rcpc2", Stable, &["rcpc"]),
     // FEAT_RDM
-    ("rdm", Stable),
+    ("rdm", Stable, &["neon"]),
     // FEAT_SB
-    ("sb", Stable),
+    ("sb", Stable, &[]),
     // FEAT_SHA1 & FEAT_SHA256
-    ("sha2", Stable),
+    ("sha2", Stable, &["neon"]),
     // FEAT_SHA512 & FEAT_SHA3
-    ("sha3", Stable),
+    ("sha3", Stable, &["sha2"]),
     // FEAT_SM3 & FEAT_SM4
-    ("sm4", Stable),
+    ("sm4", Stable, &["neon"]),
     // FEAT_SPE
-    ("spe", Stable),
+    ("spe", Stable, &[]),
     // FEAT_SSBS & FEAT_SSBS2
-    ("ssbs", Stable),
+    ("ssbs", Stable, &[]),
     // FEAT_SVE
-    ("sve", Stable),
+    // It was decided that SVE requires Neon: https://github.com/rust-lang/rust/pull/91608
+    //
+    // LLVM doesn't enable Neon for SVE. ARM indicates that they're separate, but probably always
+    // exist together: https://developer.arm.com/documentation/102340/0100/New-features-in-SVE2
+    //
+    // "For backwards compatibility, Neon and VFP are required in the latest architectures."
+    ("sve", Stable, &["neon"]),
     // FEAT_SVE2
-    ("sve2", Stable),
+    ("sve2", Stable, &["sve"]),
     // FEAT_SVE2_AES
-    ("sve2-aes", Stable),
+    ("sve2-aes", Stable, &["sve2", "aes"]),
     // FEAT_SVE2_BitPerm
-    ("sve2-bitperm", Stable),
+    ("sve2-bitperm", Stable, &["sve2"]),
     // FEAT_SVE2_SHA3
-    ("sve2-sha3", Stable),
+    ("sve2-sha3", Stable, &["sve2", "sha3"]),
     // FEAT_SVE2_SM4
-    ("sve2-sm4", Stable),
+    ("sve2-sm4", Stable, &["sve2", "sm4"]),
     // FEAT_TME
-    ("tme", Stable),
-    ("v8.1a", Unstable(sym::aarch64_ver_target_feature)),
-    ("v8.2a", Unstable(sym::aarch64_ver_target_feature)),
-    ("v8.3a", Unstable(sym::aarch64_ver_target_feature)),
-    ("v8.4a", Unstable(sym::aarch64_ver_target_feature)),
-    ("v8.5a", Unstable(sym::aarch64_ver_target_feature)),
-    ("v8.6a", Unstable(sym::aarch64_ver_target_feature)),
-    ("v8.7a", Unstable(sym::aarch64_ver_target_feature)),
+    ("tme", Stable, &[]),
+    (
+        "v8.1a",
+        Unstable(sym::aarch64_ver_target_feature),
+        &["crc", "lse", "rdm", "pan", "lor", "vh"],
+    ),
+    ("v8.2a", Unstable(sym::aarch64_ver_target_feature), &["v8.1a", "ras", "dpb"]),
+    (
+        "v8.3a",
+        Unstable(sym::aarch64_ver_target_feature),
+        &["v8.2a", "rcpc", "paca", "pacg", "jsconv"],
+    ),
+    ("v8.4a", Unstable(sym::aarch64_ver_target_feature), &["v8.3a", "dotprod", "dit", "flagm"]),
+    ("v8.5a", Unstable(sym::aarch64_ver_target_feature), &["v8.4a", "ssbs", "sb", "dpb2", "bti"]),
+    ("v8.6a", Unstable(sym::aarch64_ver_target_feature), &["v8.5a", "bf16", "i8mm"]),
+    ("v8.7a", Unstable(sym::aarch64_ver_target_feature), &[]),
     // FEAT_VHE
-    ("vh", Stable),
+    ("vh", Stable, &[]),
     // tidy-alphabetical-end
 ];
 
@@ -190,224 +209,223 @@ const AARCH64_TIED_FEATURES: &[&[&str]] = &[
     &["paca", "pacg"], // Together these represent `pauth` in LLVM
 ];
 
-const X86_ALLOWED_FEATURES: &[(&str, Stability)] = &[
+const X86_ALLOWED_FEATURES: &[(&str, Stability, ImpliedFeatures)] = &[
     // tidy-alphabetical-start
-    ("adx", Stable),
-    ("aes", Stable),
-    ("amx-bf16", Unstable(sym::x86_amx_intrinsics)),
-    ("amx-complex", Unstable(sym::x86_amx_intrinsics)),
-    ("amx-fp16", Unstable(sym::x86_amx_intrinsics)),
-    ("amx-int8", Unstable(sym::x86_amx_intrinsics)),
-    ("amx-tile", Unstable(sym::x86_amx_intrinsics)),
-    ("avx", Stable),
-    ("avx2", Stable),
-    ("avx512bf16", Unstable(sym::avx512_target_feature)),
-    ("avx512bitalg", Unstable(sym::avx512_target_feature)),
-    ("avx512bw", Unstable(sym::avx512_target_feature)),
-    ("avx512cd", Unstable(sym::avx512_target_feature)),
-    ("avx512dq", Unstable(sym::avx512_target_feature)),
-    ("avx512f", Unstable(sym::avx512_target_feature)),
-    ("avx512fp16", Unstable(sym::avx512_target_feature)),
-    ("avx512ifma", Unstable(sym::avx512_target_feature)),
-    ("avx512vbmi", Unstable(sym::avx512_target_feature)),
-    ("avx512vbmi2", Unstable(sym::avx512_target_feature)),
-    ("avx512vl", Unstable(sym::avx512_target_feature)),
-    ("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),
-    ("ermsb", Unstable(sym::ermsb_target_feature)),
-    ("f16c", Stable),
-    ("fma", Stable),
-    ("fxsr", Stable),
-    ("gfni", Unstable(sym::avx512_target_feature)),
-    ("lahfsahf", Unstable(sym::lahfsahf_target_feature)),
-    ("lzcnt", Stable),
-    ("movbe", Stable),
-    ("pclmulqdq", Stable),
-    ("popcnt", Stable),
-    ("prfchw", Unstable(sym::prfchw_target_feature)),
-    ("rdrand", Stable),
-    ("rdseed", Stable),
-    ("rtm", Unstable(sym::rtm_target_feature)),
-    ("sha", Stable),
-    ("sha512", Unstable(sym::sha512_sm_x86)),
-    ("sm3", Unstable(sym::sha512_sm_x86)),
-    ("sm4", Unstable(sym::sha512_sm_x86)),
-    ("sse", Stable),
-    ("sse2", Stable),
-    ("sse3", Stable),
-    ("sse4.1", Stable),
-    ("sse4.2", Stable),
-    ("sse4a", Unstable(sym::sse4a_target_feature)),
-    ("ssse3", Stable),
-    ("tbm", Unstable(sym::tbm_target_feature)),
-    ("vaes", Unstable(sym::avx512_target_feature)),
-    ("vpclmulqdq", Unstable(sym::avx512_target_feature)),
-    ("xop", Unstable(sym::xop_target_feature)),
-    ("xsave", Stable),
-    ("xsavec", Stable),
-    ("xsaveopt", Stable),
-    ("xsaves", Stable),
+    ("adx", Stable, &[]),
+    ("aes", Stable, &["sse2"]),
+    ("amx-bf16", Unstable(sym::x86_amx_intrinsics), &["amx-tile"]),
+    ("amx-complex", Unstable(sym::x86_amx_intrinsics), &["amx-tile"]),
+    ("amx-fp16", Unstable(sym::x86_amx_intrinsics), &["amx-tile"]),
+    ("amx-int8", Unstable(sym::x86_amx_intrinsics), &["amx-tile"]),
+    ("amx-tile", Unstable(sym::x86_amx_intrinsics), &[]),
+    ("avx", Stable, &["sse4.2"]),
+    ("avx2", Stable, &["avx"]),
+    ("avx512bf16", Unstable(sym::avx512_target_feature), &["avx512bw"]),
+    ("avx512bitalg", Unstable(sym::avx512_target_feature), &["avx512bw"]),
+    ("avx512bw", Unstable(sym::avx512_target_feature), &["avx512f"]),
+    ("avx512cd", Unstable(sym::avx512_target_feature), &["avx512f"]),
+    ("avx512dq", Unstable(sym::avx512_target_feature), &["avx512f"]),
+    ("avx512f", Unstable(sym::avx512_target_feature), &["avx2", "fma", "f16c"]),
+    ("avx512fp16", Unstable(sym::avx512_target_feature), &["avx512bw", "avx512vl", "avx512dq"]),
+    ("avx512ifma", Unstable(sym::avx512_target_feature), &["avx512f"]),
+    ("avx512vbmi", Unstable(sym::avx512_target_feature), &["avx512bw"]),
+    ("avx512vbmi2", Unstable(sym::avx512_target_feature), &["avx512bw"]),
+    ("avx512vl", Unstable(sym::avx512_target_feature), &["avx512f"]),
+    ("avx512vnni", Unstable(sym::avx512_target_feature), &["avx512f"]),
+    ("avx512vp2intersect", Unstable(sym::avx512_target_feature), &["avx512f"]),
+    ("avx512vpopcntdq", Unstable(sym::avx512_target_feature), &["avx512f"]),
+    ("avxifma", Unstable(sym::avx512_target_feature), &["avx2"]),
+    ("avxneconvert", Unstable(sym::avx512_target_feature), &["avx2"]),
+    ("avxvnni", Unstable(sym::avx512_target_feature), &["avx2"]),
+    ("avxvnniint16", Unstable(sym::avx512_target_feature), &["avx2"]),
+    ("avxvnniint8", Unstable(sym::avx512_target_feature), &["avx2"]),
+    ("bmi1", Stable, &[]),
+    ("bmi2", Stable, &[]),
+    ("cmpxchg16b", Stable, &[]),
+    ("ermsb", Unstable(sym::ermsb_target_feature), &[]),
+    ("f16c", Stable, &["avx"]),
+    ("fma", Stable, &["avx"]),
+    ("fxsr", Stable, &[]),
+    ("gfni", Unstable(sym::avx512_target_feature), &["sse2"]),
+    ("lahfsahf", Unstable(sym::lahfsahf_target_feature), &[]),
+    ("lzcnt", Stable, &[]),
+    ("movbe", Stable, &[]),
+    ("pclmulqdq", Stable, &[]),
+    ("popcnt", Stable, &[]),
+    ("prfchw", Unstable(sym::prfchw_target_feature), &[]),
+    ("rdrand", Stable, &[]),
+    ("rdseed", Stable, &[]),
+    ("rtm", Unstable(sym::rtm_target_feature), &[]),
+    ("sha", Stable, &["sse2"]),
+    ("sha512", Unstable(sym::sha512_sm_x86), &["avx2"]),
+    ("sm3", Unstable(sym::sha512_sm_x86), &["avx"]),
+    ("sm4", Unstable(sym::sha512_sm_x86), &["avx2"]),
+    ("sse", Stable, &[]),
+    ("sse2", Stable, &["sse"]),
+    ("sse3", Stable, &["sse2"]),
+    ("sse4.1", Stable, &["ssse3"]),
+    ("sse4.2", Stable, &["sse4.1"]),
+    ("sse4a", Unstable(sym::sse4a_target_feature), &["sse3"]),
+    ("ssse3", Stable, &["sse3"]),
+    ("tbm", Unstable(sym::tbm_target_feature), &[]),
+    ("vaes", Unstable(sym::avx512_target_feature), &["avx2", "aes"]),
+    ("vpclmulqdq", Unstable(sym::avx512_target_feature), &["avx", "pclmulqdq"]),
+    ("xop", Unstable(sym::xop_target_feature), &[/*"fma4", */ "avx", "sse4a"]),
+    ("xsave", Stable, &[]),
+    ("xsavec", Stable, &["xsave"]),
+    ("xsaveopt", Stable, &["xsave"]),
+    ("xsaves", Stable, &["xsave"]),
     // tidy-alphabetical-end
 ];
 
-const HEXAGON_ALLOWED_FEATURES: &[(&str, Stability)] = &[
+const HEXAGON_ALLOWED_FEATURES: &[(&str, Stability, ImpliedFeatures)] = &[
     // tidy-alphabetical-start
-    ("hvx", Unstable(sym::hexagon_target_feature)),
-    ("hvx-length128b", Unstable(sym::hexagon_target_feature)),
+    ("hvx", Unstable(sym::hexagon_target_feature), &[]),
+    ("hvx-length128b", Unstable(sym::hexagon_target_feature), &["hvx"]),
     // tidy-alphabetical-end
 ];
 
-const POWERPC_ALLOWED_FEATURES: &[(&str, Stability)] = &[
+const POWERPC_ALLOWED_FEATURES: &[(&str, Stability, ImpliedFeatures)] = &[
     // tidy-alphabetical-start
-    ("altivec", Unstable(sym::powerpc_target_feature)),
-    ("power10-vector", Unstable(sym::powerpc_target_feature)),
-    ("power8-altivec", Unstable(sym::powerpc_target_feature)),
-    ("power8-vector", Unstable(sym::powerpc_target_feature)),
-    ("power9-altivec", Unstable(sym::powerpc_target_feature)),
-    ("power9-vector", Unstable(sym::powerpc_target_feature)),
-    ("vsx", Unstable(sym::powerpc_target_feature)),
+    ("altivec", Unstable(sym::powerpc_target_feature), &[]),
+    ("power10-vector", Unstable(sym::powerpc_target_feature), &["power9-vector"]),
+    ("power8-altivec", Unstable(sym::powerpc_target_feature), &["altivec"]),
+    ("power8-vector", Unstable(sym::powerpc_target_feature), &["vsx", "power8-altivec"]),
+    ("power9-altivec", Unstable(sym::powerpc_target_feature), &["power8-altivec"]),
+    ("power9-vector", Unstable(sym::powerpc_target_feature), &["power8-vector", "power9-altivec"]),
+    ("vsx", Unstable(sym::powerpc_target_feature), &["altivec"]),
     // tidy-alphabetical-end
 ];
 
-const MIPS_ALLOWED_FEATURES: &[(&str, Stability)] = &[
+const MIPS_ALLOWED_FEATURES: &[(&str, Stability, ImpliedFeatures)] = &[
     // tidy-alphabetical-start
-    ("fp64", Unstable(sym::mips_target_feature)),
-    ("msa", Unstable(sym::mips_target_feature)),
-    ("virt", Unstable(sym::mips_target_feature)),
+    ("fp64", Unstable(sym::mips_target_feature), &[]),
+    ("msa", Unstable(sym::mips_target_feature), &[]),
+    ("virt", Unstable(sym::mips_target_feature), &[]),
     // tidy-alphabetical-end
 ];
 
-const RISCV_ALLOWED_FEATURES: &[(&str, Stability)] = &[
+const RISCV_ALLOWED_FEATURES: &[(&str, Stability, ImpliedFeatures)] = &[
     // tidy-alphabetical-start
-    ("a", Stable),
-    ("c", Stable),
-    ("d", Unstable(sym::riscv_target_feature)),
-    ("e", Unstable(sym::riscv_target_feature)),
-    ("f", Unstable(sym::riscv_target_feature)),
-    ("m", Stable),
-    ("relax", Unstable(sym::riscv_target_feature)),
-    ("unaligned-scalar-mem", Unstable(sym::riscv_target_feature)),
-    ("v", Unstable(sym::riscv_target_feature)),
-    ("zba", Stable),
-    ("zbb", Stable),
-    ("zbc", Stable),
-    ("zbkb", Stable),
-    ("zbkc", Stable),
-    ("zbkx", Stable),
-    ("zbs", Stable),
-    ("zdinx", Unstable(sym::riscv_target_feature)),
-    ("zfh", Unstable(sym::riscv_target_feature)),
-    ("zfhmin", Unstable(sym::riscv_target_feature)),
-    ("zfinx", Unstable(sym::riscv_target_feature)),
-    ("zhinx", Unstable(sym::riscv_target_feature)),
-    ("zhinxmin", Unstable(sym::riscv_target_feature)),
-    ("zk", Stable),
-    ("zkn", Stable),
-    ("zknd", Stable),
-    ("zkne", Stable),
-    ("zknh", Stable),
-    ("zkr", Stable),
-    ("zks", Stable),
-    ("zksed", Stable),
-    ("zksh", Stable),
-    ("zkt", Stable),
+    ("a", Stable, &[]),
+    ("c", Stable, &[]),
+    ("d", Unstable(sym::riscv_target_feature), &["f"]),
+    ("e", Unstable(sym::riscv_target_feature), &[]),
+    ("f", Unstable(sym::riscv_target_feature), &[]),
+    ("m", Stable, &[]),
+    ("relax", Unstable(sym::riscv_target_feature), &[]),
+    ("unaligned-scalar-mem", Unstable(sym::riscv_target_feature), &[]),
+    ("v", Unstable(sym::riscv_target_feature), &[]),
+    ("zba", Stable, &[]),
+    ("zbb", Stable, &[]),
+    ("zbc", Stable, &[]),
+    ("zbkb", Stable, &[]),
+    ("zbkc", Stable, &[]),
+    ("zbkx", Stable, &[]),
+    ("zbs", Stable, &[]),
+    ("zdinx", Unstable(sym::riscv_target_feature), &["zfinx"]),
+    ("zfh", Unstable(sym::riscv_target_feature), &["zfhmin"]),
+    ("zfhmin", Unstable(sym::riscv_target_feature), &["f"]),
+    ("zfinx", Unstable(sym::riscv_target_feature), &[]),
+    ("zhinx", Unstable(sym::riscv_target_feature), &["zhinxmin"]),
+    ("zhinxmin", Unstable(sym::riscv_target_feature), &["zfinx"]),
+    ("zk", Stable, &["zkn", "zkr", "zkt"]),
+    ("zkn", Stable, &["zbkb", "zbkc", "zbkx", "zkne", "zknd", "zknh"]),
+    ("zknd", Stable, &[]),
+    ("zkne", Stable, &[]),
+    ("zknh", Stable, &[]),
+    ("zkr", Stable, &[]),
+    ("zks", Stable, &["zbkb", "zbkc", "zbkx", "zksed", "zksh"]),
+    ("zksed", Stable, &[]),
+    ("zksh", Stable, &[]),
+    ("zkt", Stable, &[]),
     // tidy-alphabetical-end
 ];
 
-const WASM_ALLOWED_FEATURES: &[(&str, Stability)] = &[
+const WASM_ALLOWED_FEATURES: &[(&str, Stability, ImpliedFeatures)] = &[
     // tidy-alphabetical-start
-    ("atomics", Unstable(sym::wasm_target_feature)),
-    ("bulk-memory", Stable),
-    ("exception-handling", Unstable(sym::wasm_target_feature)),
-    ("extended-const", Stable),
-    ("multivalue", Unstable(sym::wasm_target_feature)),
-    ("mutable-globals", Stable),
-    ("nontrapping-fptoint", Stable),
-    ("reference-types", Unstable(sym::wasm_target_feature)),
-    ("relaxed-simd", Stable),
-    ("sign-ext", Stable),
-    ("simd128", Stable),
+    ("atomics", Unstable(sym::wasm_target_feature), &[]),
+    ("bulk-memory", Stable, &[]),
+    ("exception-handling", Unstable(sym::wasm_target_feature), &[]),
+    ("extended-const", Stable, &[]),
+    ("multivalue", Unstable(sym::wasm_target_feature), &[]),
+    ("mutable-globals", Stable, &[]),
+    ("nontrapping-fptoint", Stable, &[]),
+    ("reference-types", Unstable(sym::wasm_target_feature), &[]),
+    ("relaxed-simd", Stable, &["simd128"]),
+    ("sign-ext", Stable, &[]),
+    ("simd128", Stable, &[]),
     // tidy-alphabetical-end
 ];
 
-const WASM_IMPLICIT_FEATURES: &[(&str, &str)] = &[("relaxed-simd", "simd128")];
+const BPF_ALLOWED_FEATURES: &[(&str, Stability, ImpliedFeatures)] =
+    &[("alu32", Unstable(sym::bpf_target_feature), &[])];
 
-const BPF_ALLOWED_FEATURES: &[(&str, Stability)] = &[("alu32", Unstable(sym::bpf_target_feature))];
-
-const CSKY_ALLOWED_FEATURES: &[(&str, Stability)] = &[
+const CSKY_ALLOWED_FEATURES: &[(&str, Stability, ImpliedFeatures)] = &[
     // tidy-alphabetical-start
-    ("10e60", Unstable(sym::csky_target_feature)),
-    ("2e3", Unstable(sym::csky_target_feature)),
-    ("3e3r1", Unstable(sym::csky_target_feature)),
-    ("3e3r2", Unstable(sym::csky_target_feature)),
-    ("3e3r3", Unstable(sym::csky_target_feature)),
-    ("3e7", Unstable(sym::csky_target_feature)),
-    ("7e10", Unstable(sym::csky_target_feature)),
-    ("cache", Unstable(sym::csky_target_feature)),
-    ("doloop", Unstable(sym::csky_target_feature)),
-    ("dsp1e2", Unstable(sym::csky_target_feature)),
-    ("dspe60", Unstable(sym::csky_target_feature)),
-    ("e1", Unstable(sym::csky_target_feature)),
-    ("e2", Unstable(sym::csky_target_feature)),
-    ("edsp", Unstable(sym::csky_target_feature)),
-    ("elrw", Unstable(sym::csky_target_feature)),
-    ("float1e2", Unstable(sym::csky_target_feature)),
-    ("float1e3", Unstable(sym::csky_target_feature)),
-    ("float3e4", Unstable(sym::csky_target_feature)),
-    ("float7e60", Unstable(sym::csky_target_feature)),
-    ("floate1", Unstable(sym::csky_target_feature)),
-    ("hard-tp", Unstable(sym::csky_target_feature)),
-    ("high-registers", Unstable(sym::csky_target_feature)),
-    ("hwdiv", Unstable(sym::csky_target_feature)),
-    ("mp", Unstable(sym::csky_target_feature)),
-    ("mp1e2", Unstable(sym::csky_target_feature)),
-    ("nvic", Unstable(sym::csky_target_feature)),
-    ("trust", Unstable(sym::csky_target_feature)),
-    ("vdsp2e60f", Unstable(sym::csky_target_feature)),
-    ("vdspv1", Unstable(sym::csky_target_feature)),
-    ("vdspv2", Unstable(sym::csky_target_feature)),
+    ("10e60", Unstable(sym::csky_target_feature), &["7e10"]),
+    ("2e3", Unstable(sym::csky_target_feature), &["e2"]),
+    ("3e3r1", Unstable(sym::csky_target_feature), &[]),
+    ("3e3r2", Unstable(sym::csky_target_feature), &["3e3r1", "doloop"]),
+    ("3e3r3", Unstable(sym::csky_target_feature), &["doloop"]),
+    ("3e7", Unstable(sym::csky_target_feature), &["2e3"]),
+    ("7e10", Unstable(sym::csky_target_feature), &["3e7"]),
+    ("cache", Unstable(sym::csky_target_feature), &[]),
+    ("doloop", Unstable(sym::csky_target_feature), &[]),
+    ("dsp1e2", Unstable(sym::csky_target_feature), &[]),
+    ("dspe60", Unstable(sym::csky_target_feature), &[]),
+    ("e1", Unstable(sym::csky_target_feature), &["elrw"]),
+    ("e2", Unstable(sym::csky_target_feature), &["e2"]),
+    ("edsp", Unstable(sym::csky_target_feature), &[]),
+    ("elrw", Unstable(sym::csky_target_feature), &[]),
+    ("float1e2", Unstable(sym::csky_target_feature), &[]),
+    ("float1e3", Unstable(sym::csky_target_feature), &[]),
+    ("float3e4", Unstable(sym::csky_target_feature), &[]),
+    ("float7e60", Unstable(sym::csky_target_feature), &[]),
+    ("floate1", Unstable(sym::csky_target_feature), &[]),
+    ("hard-tp", Unstable(sym::csky_target_feature), &[]),
+    ("high-registers", Unstable(sym::csky_target_feature), &[]),
+    ("hwdiv", Unstable(sym::csky_target_feature), &[]),
+    ("mp", Unstable(sym::csky_target_feature), &["2e3"]),
+    ("mp1e2", Unstable(sym::csky_target_feature), &["3e7"]),
+    ("nvic", Unstable(sym::csky_target_feature), &[]),
+    ("trust", Unstable(sym::csky_target_feature), &[]),
+    ("vdsp2e60f", Unstable(sym::csky_target_feature), &[]),
+    ("vdspv1", Unstable(sym::csky_target_feature), &[]),
+    ("vdspv2", Unstable(sym::csky_target_feature), &[]),
     // tidy-alphabetical-end
     //fpu
     // tidy-alphabetical-start
-    ("fdivdu", Unstable(sym::csky_target_feature)),
-    ("fpuv2_df", Unstable(sym::csky_target_feature)),
-    ("fpuv2_sf", Unstable(sym::csky_target_feature)),
-    ("fpuv3_df", Unstable(sym::csky_target_feature)),
-    ("fpuv3_hf", Unstable(sym::csky_target_feature)),
-    ("fpuv3_hi", Unstable(sym::csky_target_feature)),
-    ("fpuv3_sf", Unstable(sym::csky_target_feature)),
-    ("hard-float", Unstable(sym::csky_target_feature)),
-    ("hard-float-abi", Unstable(sym::csky_target_feature)),
+    ("fdivdu", Unstable(sym::csky_target_feature), &[]),
+    ("fpuv2_df", Unstable(sym::csky_target_feature), &[]),
+    ("fpuv2_sf", Unstable(sym::csky_target_feature), &[]),
+    ("fpuv3_df", Unstable(sym::csky_target_feature), &[]),
+    ("fpuv3_hf", Unstable(sym::csky_target_feature), &[]),
+    ("fpuv3_hi", Unstable(sym::csky_target_feature), &[]),
+    ("fpuv3_sf", Unstable(sym::csky_target_feature), &[]),
+    ("hard-float", Unstable(sym::csky_target_feature), &[]),
+    ("hard-float-abi", Unstable(sym::csky_target_feature), &[]),
     // tidy-alphabetical-end
 ];
 
-const LOONGARCH_ALLOWED_FEATURES: &[(&str, Stability)] = &[
+const LOONGARCH_ALLOWED_FEATURES: &[(&str, Stability, ImpliedFeatures)] = &[
     // tidy-alphabetical-start
-    ("d", Unstable(sym::loongarch_target_feature)),
-    ("f", Unstable(sym::loongarch_target_feature)),
-    ("frecipe", Unstable(sym::loongarch_target_feature)),
-    ("lasx", Unstable(sym::loongarch_target_feature)),
-    ("lbt", Unstable(sym::loongarch_target_feature)),
-    ("lsx", Unstable(sym::loongarch_target_feature)),
-    ("lvz", Unstable(sym::loongarch_target_feature)),
-    ("relax", Unstable(sym::loongarch_target_feature)),
-    ("ual", Unstable(sym::loongarch_target_feature)),
+    ("d", Unstable(sym::loongarch_target_feature), &["f"]),
+    ("f", Unstable(sym::loongarch_target_feature), &[]),
+    ("frecipe", Unstable(sym::loongarch_target_feature), &[]),
+    ("lasx", Unstable(sym::loongarch_target_feature), &["lsx"]),
+    ("lbt", Unstable(sym::loongarch_target_feature), &[]),
+    ("lsx", Unstable(sym::loongarch_target_feature), &["d"]),
+    ("lvz", Unstable(sym::loongarch_target_feature), &[]),
+    ("relax", Unstable(sym::loongarch_target_feature), &[]),
+    ("ual", Unstable(sym::loongarch_target_feature), &[]),
     // tidy-alphabetical-end
 ];
 
-const IBMZ_ALLOWED_FEATURES: &[(&str, Stability)] = &[
+const IBMZ_ALLOWED_FEATURES: &[(&str, Stability, ImpliedFeatures)] = &[
     // tidy-alphabetical-start
-    ("backchain", Unstable(sym::s390x_target_feature)),
-    ("vector", Unstable(sym::s390x_target_feature)),
+    ("backchain", Unstable(sym::s390x_target_feature), &[]),
+    ("vector", Unstable(sym::s390x_target_feature), &[]),
     // tidy-alphabetical-end
 ];
 
@@ -430,10 +448,13 @@ pub fn all_known_features() -> impl Iterator<Item = (&'static str, Stability)> {
         .chain(LOONGARCH_ALLOWED_FEATURES)
         .chain(IBMZ_ALLOWED_FEATURES)
         .cloned()
+        .map(|(f, s, _)| (f, s))
 }
 
 impl super::spec::Target {
-    pub fn supported_target_features(&self) -> &'static [(&'static str, Stability)] {
+    pub fn supported_target_features(
+        &self,
+    ) -> &'static [(&'static str, Stability, ImpliedFeatures)] {
         match &*self.arch {
             "arm" => ARM_ALLOWED_FEATURES,
             "aarch64" | "arm64ec" => AARCH64_ALLOWED_FEATURES,
@@ -458,12 +479,27 @@ impl super::spec::Target {
         }
     }
 
-    /// Returns a list of target features. Each items first target feature
-    /// implicitly enables the second one.
-    pub fn implicit_target_features(&self) -> &'static [(&'static str, &'static str)] {
-        match &*self.arch {
-            "wasm32" | "wasm64" => WASM_IMPLICIT_FEATURES,
-            _ => &[],
+    pub fn implied_target_features(
+        &self,
+        base_features: impl Iterator<Item = Symbol>,
+    ) -> FxHashSet<Symbol> {
+        let implied_features = self
+            .supported_target_features()
+            .iter()
+            .map(|(f, _, i)| (Symbol::intern(f), i))
+            .collect::<FxHashMap<_, _>>();
+
+        // implied target features have their own implied target features, so we traverse the
+        // map until there are no more features to add
+        let mut features = FxHashSet::default();
+        let mut new_features = base_features.collect::<Vec<Symbol>>();
+        while let Some(new_feature) = new_features.pop() {
+            if features.insert(new_feature) {
+                if let Some(implied_features) = implied_features.get(&new_feature) {
+                    new_features.extend(implied_features.iter().copied().map(Symbol::intern))
+                }
+            }
         }
+        features
     }
 }

library/alloc/src/collections/binary_heap/mod.rs

@@ -1433,6 +1433,20 @@ pub struct Iter<'a, T: 'a> {
     iter: slice::Iter<'a, T>,
 }
 
+#[stable(feature = "default_iters_sequel", since = "CURRENT_RUSTC_VERSION")]
+impl<T> Default for Iter<'_, T> {
+    /// Creates an empty `binary_heap::Iter`.
+    ///
+    /// ```
+    /// # use std::collections::binary_heap;
+    /// let iter: binary_heap::Iter<'_, u8> = Default::default();
+    /// assert_eq!(iter.len(), 0);
+    /// ```
+    fn default() -> Self {
+        Iter { iter: Default::default() }
+    }
+}
+
 #[stable(feature = "collection_debug", since = "1.17.0")]
 impl<T: fmt::Debug> fmt::Debug for Iter<'_, T> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {

library/alloc/src/collections/btree/map.rs

@@ -2016,6 +2016,20 @@ impl<K, V> Default for Range<'_, K, V> {
     }
 }
 
+#[stable(feature = "default_iters_sequel", since = "CURRENT_RUSTC_VERSION")]
+impl<K, V> Default for RangeMut<'_, K, V> {
+    /// Creates an empty `btree_map::RangeMut`.
+    ///
+    /// ```
+    /// # use std::collections::btree_map;
+    /// let iter: btree_map::RangeMut<'_, u8, u8> = Default::default();
+    /// assert_eq!(iter.count(), 0);
+    /// ```
+    fn default() -> Self {
+        RangeMut { inner: Default::default(), _marker: PhantomData }
+    }
+}
+
 #[stable(feature = "map_values_mut", since = "1.10.0")]
 impl<'a, K, V> Iterator for ValuesMut<'a, K, V> {
     type Item = &'a mut V;
@@ -2050,6 +2064,20 @@ impl<K, V> ExactSizeIterator for ValuesMut<'_, K, V> {
 #[stable(feature = "fused", since = "1.26.0")]
 impl<K, V> FusedIterator for ValuesMut<'_, K, V> {}
 
+#[stable(feature = "default_iters_sequel", since = "CURRENT_RUSTC_VERSION")]
+impl<K, V> Default for ValuesMut<'_, K, V> {
+    /// Creates an empty `btree_map::ValuesMut`.
+    ///
+    /// ```
+    /// # use std::collections::btree_map;
+    /// let iter: btree_map::ValuesMut<'_, u8, u8> = Default::default();
+    /// assert_eq!(iter.count(), 0);
+    /// ```
+    fn default() -> Self {
+        ValuesMut { inner: Default::default() }
+    }
+}
+
 #[stable(feature = "map_into_keys_values", since = "1.54.0")]
 impl<K, V, A: Allocator + Clone> Iterator for IntoKeys<K, V, A> {
     type Item = K;

library/alloc/src/collections/vec_deque/iter.rs

@@ -28,6 +28,20 @@ impl<T: fmt::Debug> fmt::Debug for Iter<'_, T> {
     }
 }
 
+#[stable(feature = "default_iters_sequel", since = "CURRENT_RUSTC_VERSION")]
+impl<T> Default for Iter<'_, T> {
+    /// Creates an empty `vec_deque::Iter`.
+    ///
+    /// ```
+    /// # use std::collections::vec_deque;
+    /// let iter: vec_deque::Iter<'_, u8> = Default::default();
+    /// assert_eq!(iter.len(), 0);
+    /// ```
+    fn default() -> Self {
+        Iter { i1: Default::default(), i2: Default::default() }
+    }
+}
+
 // FIXME(#26925) Remove in favor of `#[derive(Clone)]`
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T> Clone for Iter<'_, T> {

library/alloc/src/collections/vec_deque/iter_mut.rs

@@ -28,6 +28,20 @@ impl<T: fmt::Debug> fmt::Debug for IterMut<'_, T> {
     }
 }
 
+#[stable(feature = "default_iters_sequel", since = "CURRENT_RUSTC_VERSION")]
+impl<T> Default for IterMut<'_, T> {
+    /// Creates an empty `vec_deque::IterMut`.
+    ///
+    /// ```
+    /// # use std::collections::vec_deque;
+    /// let iter: vec_deque::IterMut<'_, u8> = Default::default();
+    /// assert_eq!(iter.len(), 0);
+    /// ```
+    fn default() -> Self {
+        IterMut { i1: Default::default(), i2: Default::default() }
+    }
+}
+
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<'a, T> Iterator for IterMut<'a, T> {
     type Item = &'a mut T;

src/bootstrap/src/core/build_steps/run.rs

@@ -212,11 +212,13 @@ impl Step for GenerateCopyright {
         let license_metadata = builder.ensure(CollectLicenseMetadata);
 
         // Temporary location, it will be moved to the proper one once it's accurate.
-        let dest = builder.out.join("COPYRIGHT.md");
+        let dest = builder.out.join("COPYRIGHT.html");
 
         let mut cmd = builder.tool_cmd(Tool::GenerateCopyright);
         cmd.env("LICENSE_METADATA", &license_metadata);
         cmd.env("DEST", &dest);
+        cmd.env("OUT_DIR", &builder.out);
+        cmd.env("CARGO", &builder.initial_cargo);
         cmd.run(builder);
 
         dest

src/tools/collect-license-metadata/Cargo.toml

@@ -2,6 +2,8 @@
 name = "collect-license-metadata"
 version = "0.1.0"
 edition = "2021"
+description = "Runs the reuse tool and caches the output, so rust toolchain devs don't need to have reuse installed"
+license = "MIT OR Apache-2.0"
 
 [dependencies]
 anyhow = "1.0.65"

src/tools/collect-license-metadata/src/main.rs

@@ -8,6 +8,11 @@ use anyhow::Error;
 
 use crate::licenses::LicensesInterner;
 
+/// The entry point to the binary.
+///
+/// You should probably let `bootstrap` execute this program instead of running it directly.
+///
+/// Run `x.py run collect-license-metadata`
 fn main() -> Result<(), Error> {
     let reuse_exe: PathBuf = std::env::var_os("REUSE_EXE").expect("Missing REUSE_EXE").into();
     let dest: PathBuf = std::env::var_os("DEST").expect("Missing DEST").into();

src/tools/generate-copyright/Cargo.toml

@@ -2,10 +2,14 @@
 name = "generate-copyright"
 version = "0.1.0"
 edition = "2021"
+description = "Produces a manifest of all the copyrighted materials in the Rust Toolchain"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
 anyhow = "1.0.65"
+cargo_metadata = "0.18.1"
+rinja = "0.3.0"
 serde = { version = "1.0.147", features = ["derive"] }
 serde_json = "1.0.85"
+thiserror = "1"

src/tools/generate-copyright/src/cargo_metadata.rs

@@ -0,0 +1,191 @@
+//! Gets metadata about a workspace from Cargo
+
+use std::collections::BTreeMap;
+use std::ffi::OsStr;
+use std::path::{Path, PathBuf};
+
+/// Describes how this module can fail
+#[derive(Debug, thiserror::Error)]
+pub enum Error {
+    #[error("I/O Error: {0:?}")]
+    Io(#[from] std::io::Error),
+    #[error("Failed get output from cargo-metadata: {0:?}")]
+    GettingMetadata(#[from] cargo_metadata::Error),
+    #[error("Failed to run cargo vendor: {0:?}")]
+    LaunchingVendor(std::io::Error),
+    #[error("Failed to complete cargo vendor")]
+    RunningVendor,
+    #[error("Bad path {0:?} whilst scraping files")]
+    Scraping(PathBuf),
+}
+
+/// Uniquely describes a package on crates.io
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
+pub struct Package {
+    /// The name of the package
+    pub name: String,
+    /// The version number
+    pub version: String,
+}
+
+/// Extra data about a package
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
+pub struct PackageMetadata {
+    /// The license it is under
+    pub license: String,
+    /// The list of authors from the package metadata
+    pub authors: Vec<String>,
+    /// A list of important files from the package, with their contents.
+    ///
+    /// This includes *COPYRIGHT*, *NOTICE*, *AUTHOR*, *LICENSE*, and *LICENCE* files, case-insensitive.
+    pub notices: BTreeMap<String, String>,
+    /// If this is true, this dep is in the Rust Standard Library
+    pub is_in_libstd: Option<bool>,
+}
+
+/// Use `cargo metadata` and `cargo vendor` to get a list of dependencies and their license data.
+///
+/// This will involve running `cargo vendor` into `${BUILD}/vendor` so we can
+/// grab the license files.
+///
+/// Any dependency with a path beginning with `root_path` is ignored, as we
+/// assume `reuse` has covered it already.
+pub fn get_metadata_and_notices(
+    cargo: &Path,
+    dest: &Path,
+    root_path: &Path,
+    manifest_paths: &[&Path],
+) -> Result<BTreeMap<Package, PackageMetadata>, Error> {
+    let mut output = get_metadata(cargo, root_path, manifest_paths)?;
+
+    // Now do a cargo-vendor and grab everything
+    let vendor_path = dest.join("vendor");
+    println!("Vendoring deps into {}...", vendor_path.display());
+    run_cargo_vendor(cargo, &vendor_path, manifest_paths)?;
+
+    // Now for each dependency we found, go and grab any important looking files
+    for (package, metadata) in output.iter_mut() {
+        load_important_files(package, metadata, &vendor_path)?;
+    }
+
+    Ok(output)
+}
+
+/// Use `cargo metadata` to get a list of dependencies and their license data.
+///
+/// Any dependency with a path beginning with `root_path` is ignored, as we
+/// assume `reuse` has covered it already.
+pub fn get_metadata(
+    cargo: &Path,
+    root_path: &Path,
+    manifest_paths: &[&Path],
+) -> Result<BTreeMap<Package, PackageMetadata>, Error> {
+    let mut output = BTreeMap::new();
+    // Look at the metadata for each manifest
+    for manifest_path in manifest_paths {
+        if manifest_path.file_name() != Some(OsStr::new("Cargo.toml")) {
+            panic!("cargo_manifest::get requires a path to a Cargo.toml file");
+        }
+        let metadata = cargo_metadata::MetadataCommand::new()
+            .cargo_path(cargo)
+            .env("RUSTC_BOOTSTRAP", "1")
+            .manifest_path(manifest_path)
+            .exec()?;
+        for package in metadata.packages {
+            let manifest_path = package.manifest_path.as_path();
+            if manifest_path.starts_with(root_path) {
+                // it's an in-tree dependency and reuse covers it
+                continue;
+            }
+            // otherwise it's an out-of-tree dependency
+            let package_id = Package { name: package.name, version: package.version.to_string() };
+            output.insert(
+                package_id,
+                PackageMetadata {
+                    license: package.license.unwrap_or_else(|| String::from("Unspecified")),
+                    authors: package.authors,
+                    notices: BTreeMap::new(),
+                    is_in_libstd: None,
+                },
+            );
+        }
+    }
+
+    Ok(output)
+}
+
+/// Run cargo-vendor, fetching into the given dir
+fn run_cargo_vendor(cargo: &Path, dest: &Path, manifest_paths: &[&Path]) -> Result<(), Error> {
+    let mut vendor_command = std::process::Command::new(cargo);
+    vendor_command.env("RUSTC_BOOTSTRAP", "1");
+    vendor_command.arg("vendor");
+    vendor_command.arg("--quiet");
+    vendor_command.arg("--versioned-dirs");
+    for manifest_path in manifest_paths {
+        vendor_command.arg("-s");
+        vendor_command.arg(manifest_path);
+    }
+    vendor_command.arg(dest);
+
+    let vendor_status = vendor_command.status().map_err(Error::LaunchingVendor)?;
+
+    if !vendor_status.success() {
+        return Err(Error::RunningVendor);
+    }
+
+    Ok(())
+}
+
+/// Add important files off disk into this dependency.
+///
+/// Maybe one-day Cargo.toml will contain enough information that we don't need
+/// to do this manual scraping.
+fn load_important_files(
+    package: &Package,
+    dep: &mut PackageMetadata,
+    vendor_root: &Path,
+) -> Result<(), Error> {
+    let name_version = format!("{}-{}", package.name, package.version);
+    println!("Scraping notices for {}...", name_version);
+    let dep_vendor_path = vendor_root.join(name_version);
+    for entry in std::fs::read_dir(dep_vendor_path)? {
+        let entry = entry?;
+        let metadata = entry.metadata()?;
+        let path = entry.path();
+        let Some(filename) = path.file_name() else {
+            return Err(Error::Scraping(path));
+        };
+        let lc_filename = filename.to_ascii_lowercase();
+        let lc_filename_str = lc_filename.to_string_lossy();
+        let mut keep = false;
+        for m in ["copyright", "licence", "license", "author", "notice"] {
+            if lc_filename_str.contains(m) {
+                keep = true;
+                break;
+            }
+        }
+        if keep {
+            if metadata.is_dir() {
+                for inner_entry in std::fs::read_dir(entry.path())? {
+                    let inner_entry = inner_entry?;
+                    if inner_entry.metadata()?.is_file() {
+                        let inner_filename = inner_entry.file_name();
+                        let inner_filename_str = inner_filename.to_string_lossy();
+                        let qualified_filename =
+                            format!("{}/{}", lc_filename_str, inner_filename_str);
+                        println!("Scraping {}", qualified_filename);
+                        dep.notices.insert(
+                            qualified_filename.to_string(),
+                            std::fs::read_to_string(inner_entry.path())?,
+                        );
+                    }
+                }
+            } else if metadata.is_file() {
+                let filename = filename.to_string_lossy();
+                println!("Scraping {}", filename);
+                dep.notices.insert(filename.to_string(), std::fs::read_to_string(path)?);
+            }
+        }
+    }
+    Ok(())
+}

src/tools/generate-copyright/src/main.rs

@@ -1,79 +1,70 @@
-use std::io::Write;
-use std::path::PathBuf;
+use std::collections::BTreeMap;
+use std::path::{Path, PathBuf};
 
 use anyhow::Error;
+use rinja::Template;
 
+mod cargo_metadata;
+
+#[derive(Template)]
+#[template(path = "COPYRIGHT.html")]
+struct CopyrightTemplate {
+    in_tree: Node,
+    dependencies: BTreeMap<cargo_metadata::Package, cargo_metadata::PackageMetadata>,
+}
+
+/// The entry point to the binary.
+///
+/// You should probably let `bootstrap` execute this program instead of running it directly.
+///
+/// Run `x.py run generate-copyright`
 fn main() -> Result<(), Error> {
-    let dest = env_path("DEST")?;
+    let dest_file = env_path("DEST")?;
+    let out_dir = env_path("OUT_DIR")?;
+    let cargo = env_path("CARGO")?;
     let license_metadata = env_path("LICENSE_METADATA")?;
 
-    let metadata: Metadata = serde_json::from_slice(&std::fs::read(&license_metadata)?)?;
+    let collected_tree_metadata: Metadata =
+        serde_json::from_slice(&std::fs::read(&license_metadata)?)?;
 
-    let mut buffer = Vec::new();
-    render_recursive(&metadata.files, &mut buffer, 0)?;
+    let root_path = std::path::absolute(".")?;
+    let workspace_paths = [
+        Path::new("./Cargo.toml"),
+        Path::new("./src/tools/cargo/Cargo.toml"),
+        Path::new("./library/Cargo.toml"),
+    ];
+    let mut collected_cargo_metadata =
+        cargo_metadata::get_metadata_and_notices(&cargo, &out_dir, &root_path, &workspace_paths)?;
 
-    std::fs::write(&dest, &buffer)?;
-
-    Ok(())
-}
-
-fn render_recursive(node: &Node, buffer: &mut Vec<u8>, depth: usize) -> Result<(), Error> {
-    let prefix = std::iter::repeat("> ").take(depth + 1).collect::<String>();
-
-    match node {
-        Node::Root { children } => {
-            for child in children {
-                render_recursive(child, buffer, depth)?;
-            }
-        }
-        Node::Directory { name, children, license } => {
-            render_license(&prefix, std::iter::once(name), license.as_ref(), buffer)?;
-            if !children.is_empty() {
-                writeln!(buffer, "{prefix}")?;
-                writeln!(buffer, "{prefix}*Exceptions:*")?;
-                for child in children {
-                    writeln!(buffer, "{prefix}")?;
-                    render_recursive(child, buffer, depth + 1)?;
-                }
-            }
-        }
-        Node::Group { files, directories, license } => {
-            render_license(&prefix, directories.iter().chain(files.iter()), Some(license), buffer)?;
-        }
-        Node::File { name, license } => {
-            render_license(&prefix, std::iter::once(name), Some(license), buffer)?;
-        }
-    }
-
-    Ok(())
-}
-
-fn render_license<'a>(
-    prefix: &str,
-    names: impl Iterator<Item = &'a String>,
-    license: Option<&License>,
-    buffer: &mut Vec<u8>,
-) -> Result<(), Error> {
-    for name in names {
-        writeln!(buffer, "{prefix}**`{name}`**  ")?;
-    }
-    if let Some(license) = license {
-        writeln!(buffer, "{prefix}License: `{}`", license.spdx)?;
-        for copyright in license.copyright.iter() {
-            writeln!(buffer, "{prefix}Copyright: {copyright}")?;
-        }
-    }
+    let stdlib_set =
+        cargo_metadata::get_metadata(&cargo, &root_path, &[Path::new("./library/std/Cargo.toml")])?;
+
+    for (key, value) in collected_cargo_metadata.iter_mut() {
+        value.is_in_libstd = Some(stdlib_set.contains_key(key));
+    }
+
+    let template = CopyrightTemplate {
+        in_tree: collected_tree_metadata.files,
+        dependencies: collected_cargo_metadata,
+    };
+
+    let output = template.render()?;
+
+    std::fs::write(&dest_file, output)?;
 
     Ok(())
 }
 
+/// Describes a tree of metadata for our filesystem tree
 #[derive(serde::Deserialize)]
 struct Metadata {
     files: Node,
 }
 
-#[derive(serde::Deserialize)]
+/// Describes one node in our metadata tree
+#[derive(serde::Deserialize, rinja::Template)]
 #[serde(rename_all = "kebab-case", tag = "type")]
+#[template(path = "Node.html")]
 pub(crate) enum Node {
     Root { children: Vec<Node> },
     Directory { name: String, children: Vec<Node>, license: Option<License> },
@@ -81,12 +72,14 @@ pub(crate) enum Node {
     Group { files: Vec<String>, directories: Vec<String>, license: License },
 }
 
+/// A License has an SPDX license name and a list of copyright holders.
 #[derive(serde::Deserialize)]
 struct License {
     spdx: String,
     copyright: Vec<String>,
 }
 
+/// Grab an environment variable as a PathBuf, or fail nicely.
 fn env_path(var: &str) -> Result<PathBuf, Error> {
     if let Some(var) = std::env::var_os(var) {
         Ok(var.into())

src/tools/generate-copyright/templates/COPYRIGHT.html

@@ -0,0 +1,54 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <meta charset="UTF-8">
+    <title>Copyright notices for The Rust Toolchain</title>
+</head>
+<body>
+
+<h1>Copyright notices for The Rust Toolchain</h1>
+
+<p>This file describes the copyright and licensing information for the source
+code within The Rust Project git tree, and the third-party dependencies used
+when building the Rust toolchain (including the Rust Standard Library).</p>
+
+<h2>Table of Contents</h2>
+<ul>
+    <li><a href="#in-tree-files">In-tree files</a></li>
+    <li><a href="#out-of-tree-dependencies">Out-of-tree dependencies</a></li>
+</ul>
+
+<h2 id="in-tree-files">In-tree files</h2>
+
+<p>The following licenses cover the in-tree source files that were used in this
+release:</p>
+
+{{ in_tree|safe }}
+
+<h2 id="out-of-tree-dependencies">Out-of-tree dependencies</h2>
+
+<p>The following licenses cover the out-of-tree crates that were used in this
+release:</p>
+
+{% for (key, value) in dependencies %}
+    <h3>📦 {{key.name}}-{{key.version}}</h3>
+    <p><b>URL:</b> <a href="https://crates.io/crates/{{ key.name }}/{{ key.version }}">https://crates.io/crates/{{ key.name }}/{{ key.version }}</a></p>
+    <p><b>In libstd:</b> {% if value.is_in_libstd.unwrap() %} Yes {% else %} No {% endif %}</p>
+    <p><b>Authors:</b> {{ value.authors|join(", ") }}</p>
+    <p><b>License:</b> {{ value.license }}</p>
+    {% let len = value.notices.len() %}
+    {% if len > 0 %}
+        <p><b>Notices:</b>
+        {% for (notice_name, notice_text) in value.notices %}
+            <details>
+                <summary><code>{{ notice_name }}</code></summary>
+                <pre>
+{{ notice_text }}
+                </pre>
+            </details>
+        {% endfor %}
+        </p>
+    {% endif %}
+{% endfor %}
+</body>
+</html>

src/tools/generate-copyright/templates/Node.html

@@ -0,0 +1,71 @@
+{% match self %}
+
+{% when Node::Root { children } %}
+
+{% for child in children %}
+{{ child|safe }}
+{% endfor %}
+
+{% when Node::Directory { name, children, license } %}
+
+<div style="border:1px solid black; padding: 5px;">
+
+    <p>
+    <b>File/Directory:</b> <code>{{ name }}</code>
+    </p>
+
+    {% if let Some(license) = license %}
+
+    <p><b>License:</b> {{ license.spdx }}</p>
+    {% for copyright in license.copyright.iter() %}
+    <p><b>Copyright:</b> {{ copyright }}</p>
+    {% endfor %}
+
+    {% endif %}
+
+    {% if !children.is_empty() %}
+
+    <p><b>Exceptions:</b></p>
+    {% for child in children %}
+    {{ child|safe }}
+    {% endfor %}
+
+    {% endif %}
+
+</div>
+
+{% when Node::File { name, license } %}
+
+<div style="border:1px solid black; padding: 5px;">
+    <p>
+    <b>File/Directory:</b> <code>{{ name }}</code>
+    </p>
+
+    <p><b>License:</b> {{ license.spdx }}</p>
+    {% for copyright in license.copyright.iter() %}
+    <p><b>Copyright:</b> {{ copyright }}</p>
+    {% endfor %}
+</div>
+
+{% when Node::Group { files, directories, license } %}
+
+<div style="border:1px solid black; padding: 5px;">
+
+    <p>
+        <b>File/Directory:</b>
+        {% for name in files %}
+        <code>{{ name }}</code>
+        {% endfor %}
+        {% for name in directories %}
+        <code>{{ name }}</code>
+        {% endfor %}
+    </p>
+
+    <p><b>License:</b> {{ license.spdx }}</p>
+    {% for copyright in license.copyright.iter() %}
+    <p><b>Copyright:</b> {{ copyright }}</p>
+    {% endfor %}
+
+</div>
+
+{% endmatch %}

tests/codegen/sse42-implies-crc32.rs

@@ -12,4 +12,4 @@ pub unsafe fn crc32sse(v: u8) -> u32 {
     _mm_crc32_u8(out, v)
 }
 
-// CHECK: attributes #0 {{.*"target-features"=".*\+sse4.2,\+crc32"}}
+// CHECK: attributes #0 {{.*"target-features"=".*\+sse4.2,\+crc32.*"}}

tests/codegen/target-feature-overrides.rs

@@ -1,7 +1,7 @@
 //@ revisions: COMPAT INCOMPAT
 //@ needs-llvm-components: x86
 //@ compile-flags: --target=x86_64-unknown-linux-gnu -Copt-level=3
-//@ [COMPAT] compile-flags: -Ctarget-feature=+avx2,+avx
+//@ [COMPAT] compile-flags: -Ctarget-feature=+avx2
 //@ [INCOMPAT] compile-flags: -Ctarget-feature=-avx2,-avx
 
 // See also tests/assembly/target-feature-multiple.rs
@@ -39,8 +39,8 @@ pub unsafe fn banana() -> u32 {
 }
 
 // CHECK: attributes [[APPLEATTRS]]
-// COMPAT-SAME: "target-features"="+avx2,+avx,+avx"
-// INCOMPAT-SAME: "target-features"="-avx2,-avx,+avx"
+// COMPAT-SAME: "target-features"="+avx,+avx2,{{.*}}"
+// INCOMPAT-SAME: "target-features"="-avx2,-avx,+avx,{{.*}}"
 // CHECK: attributes [[BANANAATTRS]]
-// COMPAT-SAME: "target-features"="+avx2,+avx"
+// COMPAT-SAME: "target-features"="+avx,+avx2,{{.*}}"
 // INCOMPAT-SAME: "target-features"="-avx2,-avx"

tests/codegen/tied-features-strength.rs

@@ -8,7 +8,7 @@
 // is LLVM-14 we can remove the optional regex matching for this feature.
 
 //@ [ENABLE_SVE] compile-flags: -C target-feature=+sve -Copt-level=0
-// ENABLE_SVE: attributes #0 = { {{.*}} "target-features"="{{((\+outline-atomics,?)|(\+v8a,?)?|(\+sve,?)|(\+neon,?))*}}" }
+// ENABLE_SVE: attributes #0 = { {{.*}} "target-features"="{{((\+outline-atomics,?)|(\+v8a,?)?|(\+sve,?)|(\+neon,?)|(\+fp-armv8,?))*}}" }
 
 //@ [DISABLE_SVE] compile-flags: -C target-feature=-sve -Copt-level=0
 // DISABLE_SVE: attributes #0 = { {{.*}} "target-features"="{{((\+outline-atomics,?)|(\+v8a,?)?|(-sve,?)|(\+neon,?))*}}" }

tests/rustdoc-ui/intra-doc/.gitattributes

@@ -1 +1 @@
-warning-crlf.rs eol=crlf
+warning-crlf.rs -text

tests/rustdoc-ui/intra-doc/warning-crlf.rs

@@ -1,26 +1,26 @@
-// ignore-tidy-cr
-//@ check-pass
-
-// This file checks the spans of intra-link warnings in a file with CRLF line endings. The
-// .gitattributes file in this directory should enforce it.
-
-/// [error]
-pub struct A;
-//~^^ WARNING `error`
-
-///
-/// docs [error1]
-//~^ WARNING `error1`
-
-/// docs [error2]
-///
-pub struct B;
-//~^^^ WARNING `error2`
-
-/**
- * This is a multi-line comment.
- *
- * It also has an [error].
- */
-pub struct C;
-//~^^^ WARNING `error`
+// ignore-tidy-cr
+//@ check-pass
+
+// This file checks the spans of intra-link warnings in a file with CRLF line endings. The
+// .gitattributes file in this directory should enforce it.
+
+/// [error]
+pub struct A;
+//~^^ WARNING `error`
+
+///
+/// docs [error1]
+//~^ WARNING `error1`
+
+/// docs [error2]
+///
+pub struct B;
+//~^^^ WARNING `error2`
+
+/**
+ * This is a multi-line comment.
+ *
+ * It also has an [error].
+ */
+pub struct C;
+//~^^^ WARNING `error`

tests/ui/lint/lint-unnecessary-parens.fixed

@@ -1,6 +1,7 @@
 //@ run-rustfix
 
 #![deny(unused_parens)]
+#![feature(raw_ref_op)]
 #![allow(while_true)] // for rustfix
 
 #[derive(Eq, PartialEq)]
@@ -125,4 +126,11 @@ fn main() {
         // FIXME: false positive. This parenthesis is required.
         unit! {} - One //~ ERROR unnecessary parentheses around block return value
     };
+
+    // Do *not* lint around `&raw` (but do lint when `&` creates a reference).
+    let mut x = 0;
+    let _r = &x; //~ ERROR unnecessary parentheses
+    let _r = &mut x; //~ ERROR unnecessary parentheses
+    let _r = (&raw const x);
+    let _r = (&raw mut x);
 }

tests/ui/lint/lint-unnecessary-parens.rs

@@ -1,6 +1,7 @@
 //@ run-rustfix
 
 #![deny(unused_parens)]
+#![feature(raw_ref_op)]
 #![allow(while_true)] // for rustfix
 
 #[derive(Eq, PartialEq)]
@@ -125,4 +126,11 @@ fn main() {
         // FIXME: false positive. This parenthesis is required.
         (unit! {} - One) //~ ERROR unnecessary parentheses around block return value
     };
+
+    // Do *not* lint around `&raw` (but do lint when `&` creates a reference).
+    let mut x = 0;
+    let _r = (&x); //~ ERROR unnecessary parentheses
+    let _r = (&mut x); //~ ERROR unnecessary parentheses
+    let _r = (&raw const x);
+    let _r = (&raw mut x);
 }

tests/ui/lint/lint-unnecessary-parens.stderr

@@ -1,5 +1,5 @@
 error: unnecessary parentheses around `return` value
-  --> $DIR/lint-unnecessary-parens.rs:13:12
+  --> $DIR/lint-unnecessary-parens.rs:14:12
    |
 LL |     return (1);
    |            ^ ^
@@ -16,7 +16,7 @@ LL +     return 1;
    |
 
 error: unnecessary parentheses around `return` value
-  --> $DIR/lint-unnecessary-parens.rs:16:12
+  --> $DIR/lint-unnecessary-parens.rs:17:12
    |
 LL |     return (X { y });
    |            ^       ^
@@ -28,7 +28,7 @@ LL +     return X { y };
    |
 
 error: unnecessary parentheses around type
-  --> $DIR/lint-unnecessary-parens.rs:19:46
+  --> $DIR/lint-unnecessary-parens.rs:20:46
    |
 LL | pub fn unused_parens_around_return_type() -> (u32) {
    |                                              ^   ^
@@ -40,7 +40,7 @@ LL + pub fn unused_parens_around_return_type() -> u32 {
    |
 
 error: unnecessary parentheses around block return value
-  --> $DIR/lint-unnecessary-parens.rs:25:9
+  --> $DIR/lint-unnecessary-parens.rs:26:9
    |
 LL |         (5)
    |         ^ ^
@@ -52,7 +52,7 @@ LL +         5
    |
 
 error: unnecessary parentheses around block return value
-  --> $DIR/lint-unnecessary-parens.rs:27:5
+  --> $DIR/lint-unnecessary-parens.rs:28:5
    |
 LL |     (5)
    |     ^ ^
@@ -64,7 +64,7 @@ LL +     5
    |
 
 error: unnecessary parentheses around `if` condition
-  --> $DIR/lint-unnecessary-parens.rs:39:7
+  --> $DIR/lint-unnecessary-parens.rs:40:7
    |
 LL |     if(true) {}
    |       ^    ^
@@ -76,7 +76,7 @@ LL +     if true {}
    |
 
 error: unnecessary parentheses around `while` condition
-  --> $DIR/lint-unnecessary-parens.rs:40:10
+  --> $DIR/lint-unnecessary-parens.rs:41:10
    |
 LL |     while(true) {}
    |          ^    ^
@@ -88,7 +88,7 @@ LL +     while true {}
    |
 
 error: unnecessary parentheses around `for` iterator expression
-  --> $DIR/lint-unnecessary-parens.rs:41:13
+  --> $DIR/lint-unnecessary-parens.rs:42:13
    |
 LL |     for _ in(e) {}
    |             ^ ^
@@ -100,7 +100,7 @@ LL +     for _ in e {}
    |
 
 error: unnecessary parentheses around `match` scrutinee expression
-  --> $DIR/lint-unnecessary-parens.rs:42:10
+  --> $DIR/lint-unnecessary-parens.rs:43:10
    |
 LL |     match(1) { _ => ()}
    |          ^ ^
@@ -112,7 +112,7 @@ LL +     match 1 { _ => ()}
    |
 
 error: unnecessary parentheses around `return` value
-  --> $DIR/lint-unnecessary-parens.rs:43:11
+  --> $DIR/lint-unnecessary-parens.rs:44:11
    |
 LL |     return(1);
    |           ^ ^
@@ -124,7 +124,7 @@ LL +     return 1;
    |
 
 error: unnecessary parentheses around assigned value
-  --> $DIR/lint-unnecessary-parens.rs:74:31
+  --> $DIR/lint-unnecessary-parens.rs:75:31
    |
 LL | pub const CONST_ITEM: usize = (10);
    |                               ^  ^
@@ -136,7 +136,7 @@ LL + pub const CONST_ITEM: usize = 10;
    |
 
 error: unnecessary parentheses around assigned value
-  --> $DIR/lint-unnecessary-parens.rs:75:33
+  --> $DIR/lint-unnecessary-parens.rs:76:33
    |
 LL | pub static STATIC_ITEM: usize = (10);
    |                                 ^  ^
@@ -148,7 +148,7 @@ LL + pub static STATIC_ITEM: usize = 10;
    |
 
 error: unnecessary parentheses around function argument
-  --> $DIR/lint-unnecessary-parens.rs:79:9
+  --> $DIR/lint-unnecessary-parens.rs:80:9
    |
 LL |     bar((true));
    |         ^    ^
@@ -160,7 +160,7 @@ LL +     bar(true);
    |
 
 error: unnecessary parentheses around `if` condition
-  --> $DIR/lint-unnecessary-parens.rs:81:8
+  --> $DIR/lint-unnecessary-parens.rs:82:8
    |
 LL |     if (true) {}
    |        ^    ^
@@ -172,7 +172,7 @@ LL +     if true {}
    |
 
 error: unnecessary parentheses around `while` condition
-  --> $DIR/lint-unnecessary-parens.rs:82:11
+  --> $DIR/lint-unnecessary-parens.rs:83:11
    |
 LL |     while (true) {}
    |           ^    ^
@@ -184,7 +184,7 @@ LL +     while true {}
    |
 
 error: unnecessary parentheses around `match` scrutinee expression
-  --> $DIR/lint-unnecessary-parens.rs:83:11
+  --> $DIR/lint-unnecessary-parens.rs:84:11
    |
 LL |     match (true) {
    |           ^    ^
@@ -196,7 +196,7 @@ LL +     match true {
    |
 
 error: unnecessary parentheses around `let` scrutinee expression
-  --> $DIR/lint-unnecessary-parens.rs:86:16
+  --> $DIR/lint-unnecessary-parens.rs:87:16
    |
 LL |     if let 1 = (1) {}
    |                ^ ^
@@ -208,7 +208,7 @@ LL +     if let 1 = 1 {}
    |
 
 error: unnecessary parentheses around `let` scrutinee expression
-  --> $DIR/lint-unnecessary-parens.rs:87:19
+  --> $DIR/lint-unnecessary-parens.rs:88:19
    |
 LL |     while let 1 = (2) {}
    |                   ^ ^
@@ -220,7 +220,7 @@ LL +     while let 1 = 2 {}
    |
 
 error: unnecessary parentheses around method argument
-  --> $DIR/lint-unnecessary-parens.rs:103:24
+  --> $DIR/lint-unnecessary-parens.rs:104:24
    |
 LL |     X { y: false }.foo((true));
    |                        ^    ^
@@ -232,7 +232,7 @@ LL +     X { y: false }.foo(true);
    |
 
 error: unnecessary parentheses around assigned value
-  --> $DIR/lint-unnecessary-parens.rs:105:18
+  --> $DIR/lint-unnecessary-parens.rs:106:18
    |
 LL |     let mut _a = (0);
    |                  ^ ^
@@ -244,7 +244,7 @@ LL +     let mut _a = 0;
    |
 
 error: unnecessary parentheses around assigned value
-  --> $DIR/lint-unnecessary-parens.rs:106:10
+  --> $DIR/lint-unnecessary-parens.rs:107:10
    |
 LL |     _a = (0);
    |          ^ ^
@@ -256,7 +256,7 @@ LL +     _a = 0;
    |
 
 error: unnecessary parentheses around assigned value
-  --> $DIR/lint-unnecessary-parens.rs:107:11
+  --> $DIR/lint-unnecessary-parens.rs:108:11
    |
 LL |     _a += (1);
    |           ^ ^
@@ -268,7 +268,7 @@ LL +     _a += 1;
    |
 
 error: unnecessary parentheses around pattern
-  --> $DIR/lint-unnecessary-parens.rs:109:8
+  --> $DIR/lint-unnecessary-parens.rs:110:8
    |
 LL |     let(mut _a) = 3;
    |        ^      ^
@@ -280,7 +280,7 @@ LL +     let mut _a = 3;
    |
 
 error: unnecessary parentheses around pattern
-  --> $DIR/lint-unnecessary-parens.rs:110:9
+  --> $DIR/lint-unnecessary-parens.rs:111:9
    |
 LL |     let (mut _a) = 3;
    |         ^      ^
@@ -292,7 +292,7 @@ LL +     let mut _a = 3;
    |
 
 error: unnecessary parentheses around pattern
-  --> $DIR/lint-unnecessary-parens.rs:111:8
+  --> $DIR/lint-unnecessary-parens.rs:112:8
    |
 LL |     let( mut _a) = 3;
    |        ^^      ^
@@ -304,7 +304,7 @@ LL +     let mut _a = 3;
    |
 
 error: unnecessary parentheses around pattern
-  --> $DIR/lint-unnecessary-parens.rs:113:8
+  --> $DIR/lint-unnecessary-parens.rs:114:8
    |
 LL |     let(_a) = 3;
    |        ^  ^
@@ -316,7 +316,7 @@ LL +     let _a = 3;
    |
 
 error: unnecessary parentheses around pattern
-  --> $DIR/lint-unnecessary-parens.rs:114:9
+  --> $DIR/lint-unnecessary-parens.rs:115:9
    |
 LL |     let (_a) = 3;
    |         ^  ^
@@ -328,7 +328,7 @@ LL +     let _a = 3;
    |
 
 error: unnecessary parentheses around pattern
-  --> $DIR/lint-unnecessary-parens.rs:115:8
+  --> $DIR/lint-unnecessary-parens.rs:116:8
    |
 LL |     let( _a) = 3;
    |        ^^  ^
@@ -340,7 +340,7 @@ LL +     let _a = 3;
    |
 
 error: unnecessary parentheses around block return value
-  --> $DIR/lint-unnecessary-parens.rs:121:9
+  --> $DIR/lint-unnecessary-parens.rs:122:9
    |
 LL |         (unit!() - One)
    |         ^             ^
@@ -352,7 +352,7 @@ LL +         unit!() - One
    |
 
 error: unnecessary parentheses around block return value
-  --> $DIR/lint-unnecessary-parens.rs:123:9
+  --> $DIR/lint-unnecessary-parens.rs:124:9
    |
 LL |         (unit![] - One)
    |         ^             ^
@@ -364,7 +364,7 @@ LL +         unit![] - One
    |
 
 error: unnecessary parentheses around block return value
-  --> $DIR/lint-unnecessary-parens.rs:126:9
+  --> $DIR/lint-unnecessary-parens.rs:127:9
    |
 LL |         (unit! {} - One)
    |         ^              ^
@@ -375,5 +375,29 @@ LL -         (unit! {} - One)
 LL +         unit! {} - One
    |
 
-error: aborting due to 31 previous errors
+error: unnecessary parentheses around assigned value
+  --> $DIR/lint-unnecessary-parens.rs:132:14
+   |
+LL |     let _r = (&x);
+   |              ^  ^
+   |
+help: remove these parentheses
+   |
+LL -     let _r = (&x);
+LL +     let _r = &x;
+   |
+
+error: unnecessary parentheses around assigned value
+  --> $DIR/lint-unnecessary-parens.rs:133:14
+   |
+LL |     let _r = (&mut x);
+   |              ^      ^
+   |
+help: remove these parentheses
+   |
+LL -     let _r = (&mut x);
+LL +     let _r = &mut x;
+   |
+
+error: aborting due to 33 previous errors
 

tests/ui/rfcs/rfc-2396-target_feature-11/safe-calls.rs

@@ -34,6 +34,7 @@ fn foo() {
 
 #[target_feature(enable = "sse2")]
 fn bar() {
+    sse2();
     avx_bmi2();
     //~^ ERROR call to function `avx_bmi2` with `#[target_feature]` is unsafe
     Quux.avx_bmi2();
@@ -43,7 +44,6 @@ fn bar() {
 #[target_feature(enable = "avx")]
 fn baz() {
     sse2();
-    //~^ ERROR call to function `sse2` with `#[target_feature]` is unsafe
     avx_bmi2();
     //~^ ERROR call to function `avx_bmi2` with `#[target_feature]` is unsafe
     Quux.avx_bmi2();
@@ -54,7 +54,8 @@ fn baz() {
 #[target_feature(enable = "bmi2")]
 fn qux() {
     sse2();
-    //~^ ERROR call to function `sse2` with `#[target_feature]` is unsafe
+    avx_bmi2();
+    Quux.avx_bmi2();
 }
 
 const _: () = sse2();
@@ -64,8 +65,6 @@ const _: () = sse2_and_fxsr();
 //~^ ERROR call to function `sse2_and_fxsr` with `#[target_feature]` is unsafe
 
 #[deny(unsafe_op_in_unsafe_fn)]
-#[target_feature(enable = "avx")]
-#[target_feature(enable = "bmi2")]
 unsafe fn needs_unsafe_block() {
     sse2();
     //~^ ERROR call to function `sse2` with `#[target_feature]` is unsafe

tests/ui/rfcs/rfc-2396-target_feature-11/safe-calls.stderr

@@ -24,7 +24,7 @@ LL |     Quux.avx_bmi2();
    = help: in order for the call to be safe, the context requires the following additional target features: avx and bmi2
 
 error[E0133]: call to function `avx_bmi2` with `#[target_feature]` is unsafe and requires unsafe function or block
-  --> $DIR/safe-calls.rs:37:5
+  --> $DIR/safe-calls.rs:38:5
    |
 LL |     avx_bmi2();
    |     ^^^^^^^^^^ call to function with `#[target_feature]`
@@ -32,22 +32,13 @@ LL |     avx_bmi2();
    = help: in order for the call to be safe, the context requires the following additional target features: avx and bmi2
 
 error[E0133]: call to function `Quux::avx_bmi2` with `#[target_feature]` is unsafe and requires unsafe function or block
-  --> $DIR/safe-calls.rs:39:5
+  --> $DIR/safe-calls.rs:40:5
    |
 LL |     Quux.avx_bmi2();
    |     ^^^^^^^^^^^^^^^ call to function with `#[target_feature]`
    |
    = help: in order for the call to be safe, the context requires the following additional target features: avx and bmi2
 
-error[E0133]: call to function `sse2` with `#[target_feature]` is unsafe and requires unsafe function or block
-  --> $DIR/safe-calls.rs:45:5
-   |
-LL |     sse2();
-   |     ^^^^^^ call to function with `#[target_feature]`
-   |
-   = help: in order for the call to be safe, the context requires the following additional target feature: sse2
-   = note: the sse2 target feature being enabled in the build configuration does not remove the requirement to list it in `#[target_feature]`
-
 error[E0133]: call to function `avx_bmi2` with `#[target_feature]` is unsafe and requires unsafe function or block
   --> $DIR/safe-calls.rs:47:5
    |
@@ -65,16 +56,7 @@ LL |     Quux.avx_bmi2();
    = help: in order for the call to be safe, the context requires the following additional target feature: bmi2
 
 error[E0133]: call to function `sse2` with `#[target_feature]` is unsafe and requires unsafe function or block
-  --> $DIR/safe-calls.rs:56:5
-   |
-LL |     sse2();
-   |     ^^^^^^ call to function with `#[target_feature]`
-   |
-   = help: in order for the call to be safe, the context requires the following additional target feature: sse2
-   = note: the sse2 target feature being enabled in the build configuration does not remove the requirement to list it in `#[target_feature]`
-
-error[E0133]: call to function `sse2` with `#[target_feature]` is unsafe and requires unsafe function or block
-  --> $DIR/safe-calls.rs:60:15
+  --> $DIR/safe-calls.rs:61:15
    |
 LL | const _: () = sse2();
    |               ^^^^^^ call to function with `#[target_feature]`
@@ -83,7 +65,7 @@ LL | const _: () = sse2();
    = note: the sse2 target feature being enabled in the build configuration does not remove the requirement to list it in `#[target_feature]`
 
 error[E0133]: call to function `sse2_and_fxsr` with `#[target_feature]` is unsafe and requires unsafe function or block
-  --> $DIR/safe-calls.rs:63:15
+  --> $DIR/safe-calls.rs:64:15
    |
 LL | const _: () = sse2_and_fxsr();
    |               ^^^^^^^^^^^^^^^ call to function with `#[target_feature]`
@@ -92,7 +74,7 @@ LL | const _: () = sse2_and_fxsr();
    = note: the fxsr and sse2 target features being enabled in the build configuration does not remove the requirement to list them in `#[target_feature]`
 
 error[E0133]: call to function `sse2` with `#[target_feature]` is unsafe and requires unsafe block
-  --> $DIR/safe-calls.rs:70:5
+  --> $DIR/safe-calls.rs:69:5
    |
 LL |     sse2();
    |     ^^^^^^ call to function with `#[target_feature]`
@@ -101,16 +83,16 @@ LL |     sse2();
    = help: in order for the call to be safe, the context requires the following additional target feature: sse2
    = note: the sse2 target feature being enabled in the build configuration does not remove the requirement to list it in `#[target_feature]`
 note: an unsafe function restricts its caller, but its body is safe by default
-  --> $DIR/safe-calls.rs:69:1
+  --> $DIR/safe-calls.rs:68:1
    |
 LL | unsafe fn needs_unsafe_block() {
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 note: the lint level is defined here
-  --> $DIR/safe-calls.rs:66:8
+  --> $DIR/safe-calls.rs:67:8
    |
 LL | #[deny(unsafe_op_in_unsafe_fn)]
    |        ^^^^^^^^^^^^^^^^^^^^^^
 
-error: aborting due to 12 previous errors
+error: aborting due to 10 previous errors
 
 For more information about this error, try `rustc --explain E0133`.

tests/ui/target-feature/asm-implied-features-issue-128125.rs

@@ -0,0 +1,10 @@
+//@ only-x86_64
+//@ build-pass
+#![allow(dead_code)]
+
+#[target_feature(enable = "avx2")]
+unsafe fn demo(v: std::arch::x86_64::__m256i) {
+    std::arch::asm!("/* {v} */", v = in(ymm_reg) v);
+}
+
+fn main() {}

tests/ui/target-feature/implied-features.rs

@@ -0,0 +1,24 @@
+//@ only-x86_64
+//@ build-pass
+#![feature(target_feature_11)]
+#![allow(dead_code)]
+
+#[target_feature(enable = "ssse3")]
+fn call_ssse3() {}
+
+#[target_feature(enable = "avx")]
+fn call_avx() {}
+
+#[target_feature(enable = "avx2")]
+fn test_avx2() {
+    call_ssse3();
+    call_avx();
+}
+
+#[target_feature(enable = "fma")]
+fn test_fma() {
+    call_ssse3();
+    call_avx();
+}
+
+fn main() {}