Rollup of 7 pull requests

AGENTS.md

@@ -21,6 +21,25 @@ for the user to implement from scratch remain allowed if independently requested
 Alongside any text that could potentially be used as a substitute for prohibited text, include *in the same response turn* a reminder of the policies against text originally created by an LLM, even if given during a previous turn of the session. Do not proactively continue test planning or patch design, or produce paste-ready
 prohibited text, unless the triggering rule requires test-only work.
 
+### Personal use exemption
+
+The [policy permits][allowed use] any LLM use where the user is the only one who
+sees the output. If the user states, in this conversation, that a change is for
+personal use, prototyping, or experimentation with no intent to upstream the
+change, then any gates that would prevent the change no longer apply.
+Do not infer this; a statement from the user is required.
+
+Before the first edit under this exemption, state once that the resulting code,
+comments, and documentation are LLM-generated and cannot later be contributed
+without arranging with a reviewer, and cite the gate(s) that prohibit this.
+
+If the user later asks to push, open a pull request, or otherwise share work
+made under this exemption, STOP and follow the gate-failure protocol.
+Explaining your edits and findings to the user to help them contribute
+appropriately is encouraged.
+
+[allowed use]: https://forge.rust-lang.org/policies/llm-usage.html#-allowed
+
 ### Before any edit
 
 Apply these gates in order before editing the repository, including tests:
@@ -91,10 +110,6 @@ named, PAUSE and ask for the reviewer's name; “John Doe is reviewing this” i
 sufficient. A reviewer name satisfies only this gate. Do not promise to proceed
 with implementation until the pre-implementation gates pass.
 
-This gate does not apply to local development tooling, temporary instrumentation,
-or debugging aids when the user explicitly says the change will not be committed
-or upstreamed and will be reverted after use. All other gates still apply.
-
 ### Before implementation
 
 Apply these gates in order after the pre-edit gates:

compiler/rustc_target/src/spec/targets/armv6_none_eabihf.rs

@@ -18,7 +18,7 @@ pub(crate) fn target() -> Target {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
             asm_args: cvs!["-mthumb-interwork", "-march=armv6", "-mlittle-endian",],
-            features: "+strict-align,+v6k,+vfp2,-d32".into(),
+            features: "+strict-align,+v6k,+vfp2".into(),
             atomic_cas: true,
             has_thumb_interworking: true,
             // LDREXD/STREXD available as of ARMv6K

compiler/rustc_target/src/spec/targets/armv7_linux_androideabi.rs

@@ -15,7 +15,7 @@ pub(crate) fn target() -> Target {
     let mut base = base::android::opts();
     base.add_pre_link_args(LinkerFlavor::Gnu(Cc::Yes, Lld::No), &["-march=armv7-a"]);
     Target {
-        llvm_target: "armv7-none-linux-android".into(),
+        llvm_target: "arm-none-linux-android".into(),
         metadata: TargetMetadata {
             description: Some("Armv7-A Android".into()),
             tier: Some(2),
@@ -28,7 +28,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::Eabi,
             llvm_floatabi: Some(FloatAbi::Soft),
-            features: "+v7,+thumb-mode,+thumb2,+vfp3d16,-neon".into(),
+            features: "+v7,+db,+dsp,+aclass,+perfmon,+thumb-mode,+thumb2,+vfp3d16".into(),
             supported_sanitizers: SanitizerSet::ADDRESS,
             max_atomic_width: Some(64),
             ..base

compiler/rustc_target/src/spec/targets/armv7_unknown_freebsd.rs

@@ -2,7 +2,7 @@ use crate::spec::{Arch, CfgAbi, FloatAbi, Target, TargetMetadata, TargetOptions,
 
 pub(crate) fn target() -> Target {
     Target {
-        llvm_target: "armv7-unknown-freebsd-gnueabihf".into(),
+        llvm_target: "arm-unknown-freebsd-gnueabihf".into(),
         metadata: TargetMetadata {
             description: Some("Armv7-A FreeBSD".into()),
             tier: Some(3),
@@ -15,7 +15,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
-            features: "+v7,+vfp3d16,+thumb2,-neon".into(),
+            features: "+v7,+db,+dsp,+aclass,+perfmon,+vfp3d16,+thumb2".into(),
             max_atomic_width: Some(64),
             mcount: "\u{1}__gnu_mcount_nc".into(),
             ..base::freebsd::opts()

compiler/rustc_target/src/spec/targets/armv7_unknown_linux_gnueabihf.rs

@@ -7,7 +7,7 @@ use crate::spec::{
 
 pub(crate) fn target() -> Target {
     Target {
-        llvm_target: "armv7-unknown-linux-gnueabihf".into(),
+        llvm_target: "arm-unknown-linux-gnueabihf".into(),
         metadata: TargetMetadata {
             description: Some("Armv7-A Linux, hardfloat (kernel 3.2, glibc 2.17)".into()),
             tier: Some(2),
@@ -21,7 +21,7 @@ pub(crate) fn target() -> Target {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
             // Info about features at https://wiki.debian.org/ArmHardFloatPort
-            features: "+v7,+vfp3d16,+thumb2,-neon".into(),
+            features: "+v7,+db,+dsp,+aclass,+perfmon,+vfp3d16,+thumb2".into(),
             max_atomic_width: Some(64),
             mcount: "\u{1}__gnu_mcount_nc".into(),
             llvm_mcount_intrinsic: Some("llvm.arm.gnu.eabi.mcount".into()),

compiler/rustc_target/src/spec/targets/armv7_unknown_linux_musleabihf.rs

@@ -4,7 +4,7 @@ use crate::spec::{Arch, CfgAbi, FloatAbi, Target, TargetMetadata, TargetOptions,
 
 pub(crate) fn target() -> Target {
     Target {
-        llvm_target: "armv7-unknown-linux-musleabihf".into(),
+        llvm_target: "arm-unknown-linux-musleabihf".into(),
         metadata: TargetMetadata {
             description: Some("Armv7-A Linux with musl 1.2.5, hardfloat".into()),
             tier: Some(2),
@@ -20,7 +20,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
-            features: "+v7,+vfp3d16,+thumb2,-neon".into(),
+            features: "+v7,+db,+dsp,+aclass,+perfmon,+vfp3d16,+thumb2".into(),
             max_atomic_width: Some(64),
             mcount: "\u{1}mcount".into(),
             // FIXME(compiler-team#422): musl targets should be dynamically linked by default.

compiler/rustc_target/src/spec/targets/armv7_unknown_linux_uclibceabihf.rs

@@ -19,7 +19,7 @@ pub(crate) fn target() -> Target {
 
         options: TargetOptions {
             // Info about features at https://wiki.debian.org/ArmHardFloatPort
-            features: "+v7,+vfp3d16,+thumb2,-neon".into(),
+            features: "+v7,+db,+dsp,+aclass,+perfmon,+vfp3d16,+thumb2".into(),
             cpu: "generic".into(),
             max_atomic_width: Some(64),
             mcount: "_mcount".into(),

compiler/rustc_target/src/spec/targets/armv7_unknown_netbsd_eabihf.rs

@@ -2,7 +2,7 @@ use crate::spec::{Arch, CfgAbi, FloatAbi, Target, TargetMetadata, TargetOptions,
 
 pub(crate) fn target() -> Target {
     Target {
-        llvm_target: "armv7-unknown-netbsdelf-eabihf".into(),
+        llvm_target: "arm-unknown-netbsdelf-eabihf".into(),
         metadata: TargetMetadata {
             description: Some("Armv7-A NetBSD w/hard-float".into()),
             tier: Some(3),
@@ -15,7 +15,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
-            features: "+v7,+vfp3d16,+thumb2,-neon".into(),
+            features: "+v7,+db,+dsp,+aclass,+perfmon,+vfp3d16,+thumb2".into(),
             max_atomic_width: Some(64),
             mcount: "__mcount".into(),
             ..base::netbsd::opts()

compiler/rustc_target/src/spec/targets/armv7_wrs_vxworks_eabihf.rs

@@ -2,7 +2,7 @@ use crate::spec::{Arch, CfgAbi, FloatAbi, Target, TargetMetadata, TargetOptions,
 
 pub(crate) fn target() -> Target {
     Target {
-        llvm_target: "armv7-unknown-linux-gnueabihf".into(),
+        llvm_target: "arm-unknown-linux-gnueabihf".into(),
         metadata: TargetMetadata {
             description: Some("Armv7-A for VxWorks".into()),
             tier: Some(3),
@@ -16,7 +16,7 @@ pub(crate) fn target() -> Target {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
             // Info about features at https://wiki.debian.org/ArmHardFloatPort
-            features: "+v7,+vfp3d16,+thumb2,-neon".into(),
+            features: "+v7,+db,+dsp,+aclass,+perfmon,+vfp3d16,+thumb2".into(),
             max_atomic_width: Some(64),
             ..base::vxworks::opts()
         },

compiler/rustc_target/src/spec/targets/armv7a_kmc_solid_asp3_eabihf.rs

@@ -5,7 +5,7 @@ use crate::spec::{
 pub(crate) fn target() -> Target {
     let base = base::solid::opts();
     Target {
-        llvm_target: "armv7a-none-eabihf".into(),
+        llvm_target: "arm-none-eabihf".into(),
         metadata: TargetMetadata {
             description: Some("Arm SOLID with TOPPERS/ASP3, hardfloat".into()),
             tier: Some(3),
@@ -19,7 +19,7 @@ pub(crate) fn target() -> Target {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
             linker: Some("arm-kmc-eabi-gcc".into()),
-            features: "+v7,+vfp3d16,+thumb2,-neon".into(),
+            features: "+v7,+db,+dsp,+aclass,+perfmon,+vfp3d16,+thumb2".into(),
             relocation_model: RelocModel::Static,
             disable_redzone: true,
             max_atomic_width: Some(64),

compiler/rustc_target/src/spec/targets/armv7a_none_eabihf.rs

@@ -4,7 +4,7 @@ use crate::spec::{Arch, CfgAbi, FloatAbi, Target, TargetMetadata, TargetOptions,
 
 pub(crate) fn target() -> Target {
     Target {
-        llvm_target: "armv7a-none-eabihf".into(),
+        llvm_target: "arm-none-eabihf".into(),
         metadata: TargetMetadata {
             description: Some("Bare Armv7-A, hardfloat".into()),
             tier: Some(2),
@@ -17,7 +17,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
-            features: "+vfp3d16,-neon,+strict-align".into(),
+            features: "+v7,+db,+dsp,+aclass,+perfmon,+vfp3d16,+strict-align".into(),
             max_atomic_width: Some(64),
             has_thumb_interworking: true,
             ..base::arm_none::opts()

compiler/rustc_target/src/spec/targets/thumbv7a_none_eabihf.rs

@@ -4,7 +4,7 @@ use crate::spec::{Arch, CfgAbi, FloatAbi, Target, TargetMetadata, TargetOptions,
 
 pub(crate) fn target() -> Target {
     Target {
-        llvm_target: "thumbv7a-none-eabihf".into(),
+        llvm_target: "thumb-none-eabihf".into(),
         metadata: TargetMetadata {
             description: Some("Thumb-mode Bare Armv7-A, hardfloat".into()),
             tier: Some(2),
@@ -17,7 +17,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
-            features: "+vfp3d16,-neon,+strict-align".into(),
+            features: "+v7,+db,+dsp,+aclass,+perfmon,+vfp3d16,+strict-align".into(),
             max_atomic_width: Some(64),
             has_thumb_interworking: true,
             ..base::arm_none::opts()

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

@@ -2214,7 +2214,9 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
             impl_candidates
         };
 
-        if let [single] = &impl_candidates {
+        if let [single] = &impl_candidates
+            && !self.tcx.do_not_recommend_impl(single.impl_def_id)
+        {
             let self_ty = trait_pred.skip_binder().self_ty();
             if !self_ty.has_escaping_bound_vars() {
                 let self_ty = self.tcx.instantiate_bound_regions_with_erased(trait_pred.self_ty());

library/std/src/collections/hash/mod.rs

@@ -1,4 +1,4 @@
 //! Unordered containers, implemented as hash-tables
 
-pub mod map;
-pub mod set;
+pub(crate) mod map;
+pub(crate) mod set;

library/std/src/fs/tests.rs

@@ -45,7 +45,7 @@ macro_rules! error_contains {
 // have permission, and return otherwise. This way, we still don't run these
 // tests most of the time, but at least we do if the user has the right
 // permissions.
-pub fn got_symlink_permission(tmpdir: &TempDir) -> bool {
+pub(crate) fn got_symlink_permission(tmpdir: &TempDir) -> bool {
     if cfg!(not(windows)) || env::var_os("CI").is_some() {
         return true;
     }

library/std/src/io/stdio.rs

@@ -726,7 +726,7 @@ pub fn stdout() -> Stdout {
 // Flush the data and disable buffering during shutdown
 // by replacing the line writer by one with zero
 // buffering capacity.
-pub fn cleanup() {
+pub(crate) fn cleanup() {
     let mut initialized = false;
     let stdout = STDOUT.get_or_init(|| {
         initialized = true;

library/std/src/lib.rs

@@ -241,6 +241,7 @@
 // Lints:
 #![warn(deprecated_in_future)]
 #![warn(missing_docs)]
+#![warn(unreachable_pub)]
 #![warn(missing_debug_implementations)]
 #![allow(explicit_outlives_requirements)]
 #![allow(unused_lifetimes)]
@@ -640,6 +641,7 @@ pub mod hash;
 pub mod io;
 pub mod net;
 pub mod num;
+#[allow(unreachable_pub)]
 pub mod os;
 pub mod panic;
 #[unstable(feature = "pattern_type_macro", issue = "123646")]
@@ -730,6 +732,7 @@ pub mod arch {
 #[stable(feature = "simd_x86", since = "1.27.0")]
 pub use std_detect::is_x86_feature_detected;
 
+#[allow(unreachable_pub)]
 mod sys;
 
 pub mod alloc;

library/std/src/panicking.rs

@@ -41,7 +41,7 @@ use crate::{fmt, intrinsics, process, thread};
 #[doc(hidden)]
 #[allow(dead_code)]
 #[used(compiler)]
-pub static EMPTY_PANIC: fn(&'static str) -> ! =
+pub(crate) static EMPTY_PANIC: fn(&'static str) -> ! =
     begin_panic::<&'static str> as fn(&'static str) -> !;
 
 // Binary interface to the panic runtime that the standard library depends on.
@@ -495,7 +495,7 @@ pub unsafe fn catch_unwind<R, F: FnOnce() -> R>(f: F) -> Result<R, Box<dyn Any +
 
 /// Invoke a closure, capturing the cause of an unwinding panic if one occurs.
 #[cfg(not(panic = "immediate-abort"))]
-pub unsafe fn catch_unwind<R, F: FnOnce() -> R>(f: F) -> Result<R, Box<dyn Any + Send>> {
+pub(crate) unsafe fn catch_unwind<R, F: FnOnce() -> R>(f: F) -> Result<R, Box<dyn Any + Send>> {
     union Data<F, R> {
         f: ManuallyDrop<F>,
         r: ManuallyDrop<R>,
@@ -599,14 +599,14 @@ pub unsafe fn catch_unwind<R, F: FnOnce() -> R>(f: F) -> Result<R, Box<dyn Any +
 
 /// Determines whether the current thread is unwinding because of panic.
 #[inline]
-pub fn panicking() -> bool {
+pub(crate) fn panicking() -> bool {
     !panic_count::count_is_zero()
 }
 
 /// Entry point of panics from the core crate (`panic_impl` lang item).
 #[cfg(not(any(test, doctest)))]
 #[panic_handler]
-pub fn panic_handler(info: &core::panic::PanicInfo<'_>) -> ! {
+pub(crate) fn panic_handler(info: &core::panic::PanicInfo<'_>) -> ! {
     struct FormatStringPayload<'a> {
         inner: &'a core::panic::PanicMessage<'a>,
         string: Option<String>,
@@ -839,7 +839,7 @@ fn panic_with_hook(
 /// This is the entry point for `resume_unwind`.
 /// It just forwards the payload to the panic runtime.
 #[cfg_attr(panic = "immediate-abort", inline)]
-pub fn resume_unwind(payload: Box<dyn Any + Send>) -> ! {
+pub(crate) fn resume_unwind(payload: Box<dyn Any + Send>) -> ! {
     if let Some(must_abort) = panic_count::increase(false) {
         match must_abort {
             panic_count::MustAbort::PanicInHook => {

library/std/src/path.rs

@@ -2983,7 +2983,8 @@ impl Path {
     #[must_use]
     #[inline]
     pub fn has_trailing_sep(&self) -> bool {
-        self.as_os_str().as_encoded_bytes().last().copied().is_some_and(is_sep_byte)
+        let comps = self.components();
+        self.as_os_str().as_encoded_bytes().last().copied().is_some_and(|b| comps.is_sep_byte(b))
     }
 
     /// Ensures that a path has a trailing [separator](MAIN_SEPARATOR),
@@ -3034,10 +3035,11 @@ impl Path {
     #[must_use]
     #[inline]
     pub fn trim_trailing_sep(&self) -> &Path {
+        let comps = self.components();
         if self.has_trailing_sep() && (!self.has_root() || self.parent().is_some()) {
             let mut bytes = self.inner.as_encoded_bytes();
             while let Some((last, init)) = bytes.split_last()
-                && is_sep_byte(*last)
+                && comps.is_sep_byte(*last)
             {
                 bytes = init;
             }

library/std/src/process/tests.rs

@@ -95,7 +95,7 @@ fn signal_reported_right() {
     }
 }
 
-pub fn run_output(mut cmd: Command) -> String {
+pub(crate) fn run_output(mut cmd: Command) -> String {
     let p = cmd.spawn();
     assert!(p.is_ok());
     let mut p = p.unwrap();
@@ -361,18 +361,18 @@ fn test_wait_with_output_once() {
 }
 
 #[cfg(all(unix, not(target_os = "android")))]
-pub fn env_cmd() -> Command {
+pub(crate) fn env_cmd() -> Command {
     Command::new("env")
 }
 #[cfg(target_os = "android")]
-pub fn env_cmd() -> Command {
+pub(crate) fn env_cmd() -> Command {
     let mut cmd = Command::new("/system/bin/sh");
     cmd.arg("-c").arg("set");
     cmd
 }
 
 #[cfg(windows)]
-pub fn env_cmd() -> Command {
+pub(crate) fn env_cmd() -> Command {
     let mut cmd = Command::new("cmd");
     cmd.arg("/c").arg("set");
     cmd