diff --git a/compiler/rustc_codegen_gcc/build_system/src/test.rs b/compiler/rustc_codegen_gcc/build_system/src/test.rs
index dabf6c5aa3e..83fa8059b1a 100644
--- a/compiler/rustc_codegen_gcc/build_system/src/test.rs
+++ b/compiler/rustc_codegen_gcc/build_system/src/test.rs
@@ -552,7 +552,7 @@ fn asm_tests(env: &Env, args: &TestArg) -> Result<(), String> {
             &"--stage",
             &"0",
             &"tests/assembly/asm",
-            &"--rustc-args",
+            &"--compiletest-rustc-args",
             &rustc_args,
         ],
         Some(&rust_dir),
@@ -1020,7 +1020,7 @@ fn file_handling(file_path: &Path) -> Result<(), String> {
             &"--stage",
             &"0",
             &format!("tests/{}", test_type),
-            &"--rustc-args",
+            &"--compiletest-rustc-args",
             &rustc_args,
         ],
         Some(&rust_path),
diff --git a/compiler/rustc_target/src/abi/call/powerpc64.rs b/compiler/rustc_target/src/abi/call/powerpc64.rs
index 11a6cb52bab..749eea0ef63 100644
--- a/compiler/rustc_target/src/abi/call/powerpc64.rs
+++ b/compiler/rustc_target/src/abi/call/powerpc64.rs
@@ -41,59 +41,12 @@ fn is_homogeneous_aggregate<'a, Ty, C>(
     })
 }
 
-fn classify_ret<'a, Ty, C>(cx: &C, ret: &mut ArgAbi<'a, Ty>, abi: ABI)
+fn classify<'a, Ty, C>(cx: &C, arg: &mut ArgAbi<'a, Ty>, abi: ABI, is_ret: bool)
 where
     Ty: TyAbiInterface<'a, C> + Copy,
     C: HasDataLayout,
 {
-    if !ret.layout.is_sized() {
-        // Not touching this...
-        return;
-    }
-    if !ret.layout.is_aggregate() {
-        ret.extend_integer_width_to(64);
-        return;
-    }
-
-    // The ELFv1 ABI doesn't return aggregates in registers
-    if abi == ELFv1 {
-        ret.make_indirect();
-        return;
-    }
-
-    if let Some(uniform) = is_homogeneous_aggregate(cx, ret, abi) {
-        ret.cast_to(uniform);
-        return;
-    }
-
-    let size = ret.layout.size;
-    let bits = size.bits();
-    if bits <= 128 {
-        let unit = if cx.data_layout().endian == Endian::Big {
-            Reg { kind: RegKind::Integer, size }
-        } else if bits <= 8 {
-            Reg::i8()
-        } else if bits <= 16 {
-            Reg::i16()
-        } else if bits <= 32 {
-            Reg::i32()
-        } else {
-            Reg::i64()
-        };
-
-        ret.cast_to(Uniform::new(unit, size));
-        return;
-    }
-
-    ret.make_indirect();
-}
-
-fn classify_arg<'a, Ty, C>(cx: &C, arg: &mut ArgAbi<'a, Ty>, abi: ABI)
-where
-    Ty: TyAbiInterface<'a, C> + Copy,
-    C: HasDataLayout,
-{
-    if !arg.layout.is_sized() {
+    if arg.is_ignore() || !arg.layout.is_sized() {
         // Not touching this...
         return;
     }
@@ -102,13 +55,22 @@ fn classify_arg<'a, Ty, C>(cx: &C, arg: &mut ArgAbi<'a, Ty>, abi: ABI)
         return;
     }
 
+    // The ELFv1 ABI doesn't return aggregates in registers
+    if is_ret && abi == ELFv1 {
+        arg.make_indirect();
+        return;
+    }
+
     if let Some(uniform) = is_homogeneous_aggregate(cx, arg, abi) {
         arg.cast_to(uniform);
         return;
     }
 
     let size = arg.layout.size;
-    if size.bits() <= 64 {
+    if is_ret && size.bits() > 128 {
+        // Non-homogeneous aggregates larger than two doublewords are returned indirectly.
+        arg.make_indirect();
+    } else if size.bits() <= 64 {
         // Aggregates smaller than a doubleword should appear in
         // the least-significant bits of the parameter doubleword.
         arg.cast_to(Reg { kind: RegKind::Integer, size })
@@ -138,14 +100,9 @@ pub fn compute_abi_info<'a, Ty, C>(cx: &C, fn_abi: &mut FnAbi<'a, Ty>)
         }
     };
 
-    if !fn_abi.ret.is_ignore() {
-        classify_ret(cx, &mut fn_abi.ret, abi);
-    }
+    classify(cx, &mut fn_abi.ret, abi, true);
 
     for arg in fn_abi.args.iter_mut() {
-        if arg.is_ignore() {
-            continue;
-        }
-        classify_arg(cx, arg, abi);
+        classify(cx, arg, abi, false);
     }
 }
diff --git a/library/std/src/sys/pal/unix/rand.rs b/library/std/src/sys/pal/unix/rand.rs
index 8a78ea8e7cc..cc0852aab43 100644
--- a/library/std/src/sys/pal/unix/rand.rs
+++ b/library/std/src/sys/pal/unix/rand.rs
@@ -2,7 +2,9 @@ pub fn hashmap_random_keys() -> (u64, u64) {
     const KEY_LEN: usize = core::mem::size_of::<u64>();
 
     let mut v = [0u8; KEY_LEN * 2];
-    imp::fill_bytes(&mut v);
+    if let Err(err) = read(&mut v) {
+        panic!("failed to retrieve random hash map seed: {err}");
+    }
 
     let key1 = v[0..KEY_LEN].try_into().unwrap();
     let key2 = v[KEY_LEN..].try_into().unwrap();
@@ -10,27 +12,78 @@ pub fn hashmap_random_keys() -> (u64, u64) {
     (u64::from_ne_bytes(key1), u64::from_ne_bytes(key2))
 }
 
-#[cfg(all(
-    unix,
-    not(target_os = "openbsd"),
-    not(target_os = "netbsd"),
-    not(target_os = "fuchsia"),
-    not(target_os = "redox"),
-    not(target_os = "vxworks"),
-    not(target_os = "emscripten"),
-    not(target_os = "vita"),
-    not(target_vendor = "apple"),
+cfg_if::cfg_if! {
+    if #[cfg(any(
+        target_vendor = "apple",
+        target_os = "openbsd",
+        target_os = "emscripten",
+        target_os = "vita",
+        all(target_os = "netbsd", not(netbsd10)),
+        target_os = "fuchsia",
+        target_os = "vxworks",
+    ))] {
+        // Some systems have a syscall that directly retrieves random data.
+        // If that is guaranteed to be available, use it.
+        use imp::syscall as read;
+    } else {
+        // Otherwise, try the syscall to see if it exists only on some systems
+        // and fall back to reading from the random device otherwise.
+        fn read(bytes: &mut [u8]) -> crate::io::Result<()> {
+            use crate::fs::File;
+            use crate::io::Read;
+            use crate::sync::OnceLock;
+
+            #[cfg(any(
+                target_os = "linux",
+                target_os = "android",
+                target_os = "espidf",
+                target_os = "horizon",
+                target_os = "freebsd",
+                target_os = "dragonfly",
+                target_os = "solaris",
+                target_os = "illumos",
+                netbsd10,
+            ))]
+            if let Some(res) = imp::syscall(bytes) {
+                return res;
+            }
+
+            const PATH: &'static str = if cfg!(target_os = "redox") {
+                "/scheme/rand"
+            } else {
+                "/dev/urandom"
+            };
+
+            static FILE: OnceLock<File> = OnceLock::new();
+
+            FILE.get_or_try_init(|| File::open(PATH))?.read_exact(bytes)
+        }
+    }
+}
+
+// All these systems a `getrandom` syscall.
+//
+// It is not guaranteed to be available, so return None to fallback to the file
+// implementation.
+#[cfg(any(
+    target_os = "linux",
+    target_os = "android",
+    target_os = "espidf",
+    target_os = "horizon",
+    target_os = "freebsd",
+    target_os = "dragonfly",
+    target_os = "solaris",
+    target_os = "illumos",
+    netbsd10,
 ))]
 mod imp {
-    use crate::fs::File;
-    use crate::io::Read;
-    #[cfg(any(target_os = "linux", target_os = "android"))]
-    use crate::sys::weak::syscall;
+    use crate::io::{Error, Result};
+    use crate::sync::atomic::{AtomicBool, Ordering};
+    use crate::sys::os::errno;
 
     #[cfg(any(target_os = "linux", target_os = "android"))]
     fn getrandom(buf: &mut [u8]) -> libc::ssize_t {
-        use crate::sync::atomic::{AtomicBool, Ordering};
-        use crate::sys::os::errno;
+        use crate::sys::weak::syscall;
 
         // A weak symbol allows interposition, e.g. for perf measurements that want to
         // disable randomness for consistency. Otherwise, we'll try a raw syscall.
@@ -59,6 +112,7 @@ fn getrandom(
     }
 
     #[cfg(any(
+        target_os = "dragonfly",
         target_os = "espidf",
         target_os = "horizon",
         target_os = "freebsd",
@@ -70,51 +124,11 @@ fn getrandom(buf: &mut [u8]) -> libc::ssize_t {
         unsafe { libc::getrandom(buf.as_mut_ptr().cast(), buf.len(), 0) }
     }
 
-    #[cfg(target_os = "dragonfly")]
-    fn getrandom(buf: &mut [u8]) -> libc::ssize_t {
-        extern "C" {
-            fn getrandom(
-                buf: *mut libc::c_void,
-                buflen: libc::size_t,
-                flags: libc::c_uint,
-            ) -> libc::ssize_t;
-        }
-        unsafe { getrandom(buf.as_mut_ptr().cast(), buf.len(), 0) }
-    }
-
-    #[cfg(not(any(
-        target_os = "linux",
-        target_os = "android",
-        target_os = "espidf",
-        target_os = "horizon",
-        target_os = "freebsd",
-        target_os = "dragonfly",
-        target_os = "solaris",
-        target_os = "illumos",
-        netbsd10
-    )))]
-    fn getrandom_fill_bytes(_buf: &mut [u8]) -> bool {
-        false
-    }
-
-    #[cfg(any(
-        target_os = "linux",
-        target_os = "android",
-        target_os = "espidf",
-        target_os = "horizon",
-        target_os = "freebsd",
-        target_os = "dragonfly",
-        target_os = "solaris",
-        target_os = "illumos",
-        netbsd10
-    ))]
-    fn getrandom_fill_bytes(v: &mut [u8]) -> bool {
-        use crate::sync::atomic::{AtomicBool, Ordering};
-        use crate::sys::os::errno;
-
+    pub fn syscall(v: &mut [u8]) -> Option<Result<()>> {
         static GETRANDOM_UNAVAILABLE: AtomicBool = AtomicBool::new(false);
+
         if GETRANDOM_UNAVAILABLE.load(Ordering::Relaxed) {
-            return false;
+            return None;
         }
 
         let mut read = 0;
@@ -125,8 +139,7 @@ fn getrandom_fill_bytes(v: &mut [u8]) -> bool {
                 if err == libc::EINTR {
                     continue;
                 } else if err == libc::ENOSYS || err == libc::EPERM {
-                    // Fall back to reading /dev/urandom if `getrandom` is not
-                    // supported on the current kernel.
+                    // `getrandom` is not supported on the current system.
                     //
                     // Also fall back in case it is disabled by something like
                     // seccomp or inside of docker.
@@ -142,123 +155,83 @@ fn getrandom_fill_bytes(v: &mut [u8]) -> bool {
                     //     https://github.com/moby/moby/issues/42680
                     //
                     GETRANDOM_UNAVAILABLE.store(true, Ordering::Relaxed);
-                    return false;
+                    return None;
                 } else if err == libc::EAGAIN {
-                    return false;
+                    // getrandom has failed because it would have blocked as the
+                    // non-blocking pool (urandom) has not been initialized in
+                    // the kernel yet due to a lack of entropy. Fallback to
+                    // reading from `/dev/urandom` which will return potentially
+                    // insecure random data to avoid blocking applications which
+                    // could depend on this call without ever knowing they do and
+                    // don't have a work around.
+                    return None;
                 } else {
-                    panic!("unexpected getrandom error: {err}");
+                    return Some(Err(Error::from_raw_os_error(err)));
                 }
             } else {
                 read += result as usize;
             }
         }
-        true
-    }
 
-    pub fn fill_bytes(v: &mut [u8]) {
-        // getrandom_fill_bytes here can fail if getrandom() returns EAGAIN,
-        // meaning it would have blocked because the non-blocking pool (urandom)
-        // has not initialized in the kernel yet due to a lack of entropy. The
-        // fallback we do here is to avoid blocking applications which could
-        // depend on this call without ever knowing they do and don't have a
-        // work around. The PRNG of /dev/urandom will still be used but over a
-        // possibly predictable entropy pool.
-        if getrandom_fill_bytes(v) {
-            return;
-        }
-
-        // getrandom failed because it is permanently or temporarily (because
-        // of missing entropy) unavailable. Open /dev/urandom, read from it,
-        // and close it again.
-        let mut file = File::open("/dev/urandom").expect("failed to open /dev/urandom");
-        file.read_exact(v).expect("failed to read /dev/urandom")
+        Some(Ok(()))
     }
 }
 
-#[cfg(target_vendor = "apple")]
+#[cfg(any(
+    target_os = "macos", // Supported since macOS 10.12+.
+    target_os = "openbsd",
+    target_os = "emscripten",
+    target_os = "vita",
+))]
 mod imp {
-    use libc::{c_int, c_void, size_t};
-
-    use crate::io;
-
-    #[inline(always)]
-    fn random_failure() -> ! {
-        panic!("unexpected random generation error: {}", io::Error::last_os_error());
-    }
-
-    #[cfg(target_os = "macos")]
-    fn getentropy_fill_bytes(v: &mut [u8]) {
-        extern "C" {
-            fn getentropy(bytes: *mut c_void, count: size_t) -> c_int;
-        }
+    use crate::io::{Error, Result};
 
+    pub fn syscall(v: &mut [u8]) -> Result<()> {
         // getentropy(2) permits a maximum buffer size of 256 bytes
         for s in v.chunks_mut(256) {
-            let ret = unsafe { getentropy(s.as_mut_ptr().cast(), s.len()) };
+            let ret = unsafe { libc::getentropy(s.as_mut_ptr().cast(), s.len()) };
             if ret == -1 {
-                random_failure()
+                return Err(Error::last_os_error());
             }
         }
-    }
 
-    #[cfg(not(target_os = "macos"))]
-    fn ccrandom_fill_bytes(v: &mut [u8]) {
+        Ok(())
+    }
+}
+
+// On Apple platforms, `CCRandomGenerateBytes` and `SecRandomCopyBytes` simply
+// call into `CCRandomCopyBytes` with `kCCRandomDefault`. `CCRandomCopyBytes`
+// manages a CSPRNG which is seeded from the kernel's CSPRNG and which runs on
+// its own thread accessed via GCD. This seems needlessly heavyweight for our purposes
+// so we only use it when `getentropy` is blocked, which appears to be the case
+// on all platforms except macOS (see #102643).
+//
+// `CCRandomGenerateBytes` is used instead of `SecRandomCopyBytes` because the former is accessible
+// via `libSystem` (libc) while the other needs to link to `Security.framework`.
+#[cfg(all(target_vendor = "apple", not(target_os = "macos")))]
+mod imp {
+    use libc::size_t;
+
+    use crate::ffi::{c_int, c_void};
+    use crate::io::{Error, Result};
+
+    pub fn syscall(v: &mut [u8]) -> Result<()> {
         extern "C" {
             fn CCRandomGenerateBytes(bytes: *mut c_void, count: size_t) -> c_int;
         }
 
         let ret = unsafe { CCRandomGenerateBytes(v.as_mut_ptr().cast(), v.len()) };
-        if ret == -1 {
-            random_failure()
-        }
-    }
-
-    pub fn fill_bytes(v: &mut [u8]) {
-        // All supported versions of macOS (10.12+) support getentropy.
-        //
-        // `getentropy` is measurably faster (via Divan) then the other alternatives so its preferred
-        // when usable.
-        #[cfg(target_os = "macos")]
-        getentropy_fill_bytes(v);
-
-        // On Apple platforms, `CCRandomGenerateBytes` and `SecRandomCopyBytes` simply
-        // call into `CCRandomCopyBytes` with `kCCRandomDefault`. `CCRandomCopyBytes`
-        // manages a CSPRNG which is seeded from the kernel's CSPRNG and which runs on
-        // its own thread accessed via GCD. This seems needlessly heavyweight for our purposes
-        // so we only use it on non-Mac OSes where the better entrypoints are blocked.
-        //
-        // `CCRandomGenerateBytes` is used instead of `SecRandomCopyBytes` because the former is accessible
-        // via `libSystem` (libc) while the other needs to link to `Security.framework`.
-        //
-        // Note that while `getentropy` has a available attribute in the macOS headers, the lack
-        // of a header in the iOS (and others) SDK means that its can cause app store rejections.
-        // Just use `CCRandomGenerateBytes` instead.
-        #[cfg(not(target_os = "macos"))]
-        ccrandom_fill_bytes(v);
-    }
-}
-
-#[cfg(any(target_os = "openbsd", target_os = "emscripten", target_os = "vita"))]
-mod imp {
-    use crate::sys::os::errno;
-
-    pub fn fill_bytes(v: &mut [u8]) {
-        // getentropy(2) permits a maximum buffer size of 256 bytes
-        for s in v.chunks_mut(256) {
-            let ret = unsafe { libc::getentropy(s.as_mut_ptr() as *mut libc::c_void, s.len()) };
-            if ret == -1 {
-                panic!("unexpected getentropy error: {}", errno());
-            }
-        }
+        if ret != -1 { Ok(()) } else { Err(Error::last_os_error()) }
     }
 }
 
 // FIXME: once the 10.x release becomes the minimum, this can be dropped for simplification.
 #[cfg(all(target_os = "netbsd", not(netbsd10)))]
 mod imp {
+    use crate::io::{Error, Result};
     use crate::ptr;
 
-    pub fn fill_bytes(v: &mut [u8]) {
+    pub fn syscall(v: &mut [u8]) -> Result<()> {
         let mib = [libc::CTL_KERN, libc::KERN_ARND];
         // kern.arandom permits a maximum buffer size of 256 bytes
         for s in v.chunks_mut(256) {
@@ -273,39 +246,30 @@ pub fn fill_bytes(v: &mut [u8]) {
                     0,
                 )
             };
-            if ret == -1 || s_len != s.len() {
-                panic!(
-                    "kern.arandom sysctl failed! (returned {}, s.len() {}, oldlenp {})",
-                    ret,
-                    s.len(),
-                    s_len
-                );
+            if ret == -1 {
+                return Err(Error::last_os_error());
+            } else if s_len != s.len() {
+                // FIXME(joboet): this can't actually happen, can it?
+                panic!("read less bytes than requested from kern.arandom");
             }
         }
+
+        Ok(())
     }
 }
 
 #[cfg(target_os = "fuchsia")]
 mod imp {
+    use crate::io::Result;
+
     #[link(name = "zircon")]
     extern "C" {
         fn zx_cprng_draw(buffer: *mut u8, len: usize);
     }
 
-    pub fn fill_bytes(v: &mut [u8]) {
-        unsafe { zx_cprng_draw(v.as_mut_ptr(), v.len()) }
-    }
-}
-
-#[cfg(target_os = "redox")]
-mod imp {
-    use crate::fs::File;
-    use crate::io::Read;
-
-    pub fn fill_bytes(v: &mut [u8]) {
-        // Open rand:, read from it, and close it again.
-        let mut file = File::open("rand:").expect("failed to open rand:");
-        file.read_exact(v).expect("failed to read rand:")
+    pub fn syscall(v: &mut [u8]) -> Result<()> {
+        unsafe { zx_cprng_draw(v.as_mut_ptr(), v.len()) };
+        Ok(())
     }
 }
 
@@ -314,25 +278,25 @@ mod imp {
     use core::sync::atomic::AtomicBool;
     use core::sync::atomic::Ordering::Relaxed;
 
-    use crate::io;
+    use crate::io::{Error, Result};
 
-    pub fn fill_bytes(v: &mut [u8]) {
+    pub fn syscall(v: &mut [u8]) -> Result<()> {
         static RNG_INIT: AtomicBool = AtomicBool::new(false);
         while !RNG_INIT.load(Relaxed) {
             let ret = unsafe { libc::randSecure() };
             if ret < 0 {
-                panic!("couldn't generate random bytes: {}", io::Error::last_os_error());
+                return Err(Error::last_os_error());
             } else if ret > 0 {
                 RNG_INIT.store(true, Relaxed);
                 break;
             }
+
             unsafe { libc::usleep(10) };
         }
+
         let ret = unsafe {
             libc::randABytes(v.as_mut_ptr() as *mut libc::c_uchar, v.len() as libc::c_int)
         };
-        if ret < 0 {
-            panic!("couldn't generate random bytes: {}", io::Error::last_os_error());
-        }
+        if ret >= 0 { Ok(()) } else { Err(Error::last_os_error()) }
     }
 }
diff --git a/library/std/src/thread/mod.rs b/library/std/src/thread/mod.rs
index 59720f77465..88b31cd78a6 100644
--- a/library/std/src/thread/mod.rs
+++ b/library/std/src/thread/mod.rs
@@ -434,25 +434,24 @@ pub fn spawn<F, T>(self, f: F) -> io::Result<JoinHandle<T>>
     ///
     /// [`io::Result`]: crate::io::Result
     #[unstable(feature = "thread_spawn_unchecked", issue = "55132")]
-    pub unsafe fn spawn_unchecked<'a, F, T>(self, f: F) -> io::Result<JoinHandle<T>>
+    pub unsafe fn spawn_unchecked<F, T>(self, f: F) -> io::Result<JoinHandle<T>>
     where
         F: FnOnce() -> T,
-        F: Send + 'a,
-        T: Send + 'a,
+        F: Send,
+        T: Send,
     {
         Ok(JoinHandle(unsafe { self.spawn_unchecked_(f, None) }?))
     }
 
-    unsafe fn spawn_unchecked_<'a, 'scope, F, T>(
+    unsafe fn spawn_unchecked_<'scope, F, T>(
         self,
         f: F,
         scope_data: Option<Arc<scoped::ScopeData>>,
     ) -> io::Result<JoinInner<'scope, T>>
     where
         F: FnOnce() -> T,
-        F: Send + 'a,
-        T: Send + 'a,
-        'scope: 'a,
+        F: Send,
+        T: Send,
     {
         let Builder { name, stack_size } = self;
 
@@ -532,7 +531,7 @@ fn drop(&mut self) {
             // will call `decrement_num_running_threads` and therefore signal that this thread is
             // done.
             drop(their_packet);
-            // Here, the lifetime `'a` and even `'scope` can end. `main` keeps running for a bit
+            // Here, the lifetime `'scope` can end. `main` keeps running for a bit
             // after that before returning itself.
         };
 
diff --git a/src/bootstrap/src/core/build_steps/clean.rs b/src/bootstrap/src/core/build_steps/clean.rs
index 49310367182..f608e5d715e 100644
--- a/src/bootstrap/src/core/build_steps/clean.rs
+++ b/src/bootstrap/src/core/build_steps/clean.rs
@@ -121,7 +121,7 @@ fn clean(build: &Build, all: bool, stage: Option<u32>) {
 
 fn clean_specific_stage(build: &Build, stage: u32) {
     for host in &build.hosts {
-        let entries = match build.out.join(host.triple).read_dir() {
+        let entries = match build.out.join(host).read_dir() {
             Ok(iter) => iter,
             Err(_) => continue,
         };
@@ -148,7 +148,7 @@ fn clean_default(build: &Build) {
     rm_rf(&build.out.join("bootstrap-shims-dump"));
     rm_rf(&build.out.join("rustfmt.stamp"));
 
-    let mut hosts: Vec<_> = build.hosts.iter().map(|t| build.out.join(t.triple)).collect();
+    let mut hosts: Vec<_> = build.hosts.iter().map(|t| build.out.join(t)).collect();
     // After cross-compilation, artifacts of the host architecture (which may differ from build.host)
     // might not get removed.
     // Adding its path (linked one for easier accessibility) will solve this problem.
diff --git a/src/bootstrap/src/core/build_steps/compile.rs b/src/bootstrap/src/core/build_steps/compile.rs
index c09180e542f..4353cfadd8d 100644
--- a/src/bootstrap/src/core/build_steps/compile.rs
+++ b/src/bootstrap/src/core/build_steps/compile.rs
@@ -246,7 +246,7 @@ fn run(self, builder: &Builder<'_>) {
                 .rustc_snapshot_sysroot()
                 .join("lib")
                 .join("rustlib")
-                .join(compiler.host.triple)
+                .join(compiler.host)
                 .join("bin");
             if src_sysroot_bin.exists() {
                 let target_sysroot_bin =
@@ -432,7 +432,7 @@ fn copy_self_contained_objects(
                 DependencyType::TargetSelfContained,
             );
         }
-    } else if target.ends_with("windows-gnu") {
+    } else if target.is_windows_gnu() {
         for obj in ["crt2.o", "dllcrt2.o"].iter() {
             let src = compiler_file(builder, &builder.cc(target), target, CLang::C, obj);
             let target = libdir_self_contained.join(obj);
@@ -651,8 +651,8 @@ fn run(self, builder: &Builder<'_>) {
                 compiler: self.compiler,
                 force_recompile: self.force_recompile,
             });
-            let libdir = sysroot.join(lib).join("rustlib").join(target.triple).join("lib");
-            let hostdir = sysroot.join(lib).join("rustlib").join(compiler.host.triple).join("lib");
+            let libdir = sysroot.join(lib).join("rustlib").join(target).join("lib");
+            let hostdir = sysroot.join(lib).join("rustlib").join(compiler.host).join("lib");
             (libdir, hostdir)
         } else {
             let libdir = builder.sysroot_libdir(target_compiler, target);
@@ -670,12 +670,12 @@ fn run(self, builder: &Builder<'_>) {
                 .build
                 .config
                 .initial_rustc
-                .starts_with(builder.out.join(compiler.host.triple).join("stage0/bin"))
+                .starts_with(builder.out.join(compiler.host).join("stage0/bin"))
         {
             // Copy bin files from stage0/bin to stage0-sysroot/bin
-            let sysroot = builder.out.join(compiler.host.triple).join("stage0-sysroot");
+            let sysroot = builder.out.join(compiler.host).join("stage0-sysroot");
 
-            let host = compiler.host.triple;
+            let host = compiler.host;
             let stage0_bin_dir = builder.out.join(host).join("stage0/bin");
             let sysroot_bin_dir = sysroot.join("bin");
             t!(fs::create_dir_all(&sysroot_bin_dir));
@@ -793,7 +793,7 @@ fn make_run(run: RunConfig<'_>) {
     fn run(self, builder: &Builder<'_>) -> Vec<(PathBuf, DependencyType)> {
         let for_compiler = self.compiler;
         let target = self.target;
-        if !target.ends_with("windows-gnu") {
+        if !target.is_windows_gnu() {
             return vec![];
         }
 
@@ -1554,7 +1554,7 @@ fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
     /// For all other stages, it's the same stage directory that the compiler lives in.
     fn run(self, builder: &Builder<'_>) -> PathBuf {
         let compiler = self.compiler;
-        let host_dir = builder.out.join(compiler.host.triple);
+        let host_dir = builder.out.join(compiler.host);
 
         let sysroot_dir = |stage| {
             if stage == 0 {
diff --git a/src/bootstrap/src/core/build_steps/dist.rs b/src/bootstrap/src/core/build_steps/dist.rs
index 43306eab1b1..530eb9b446a 100644
--- a/src/bootstrap/src/core/build_steps/dist.rs
+++ b/src/bootstrap/src/core/build_steps/dist.rs
@@ -275,12 +275,8 @@ fn make_win_dist(
     }
 
     //Copy platform tools to platform-specific bin directory
-    let target_bin_dir = plat_root
-        .join("lib")
-        .join("rustlib")
-        .join(target.triple)
-        .join("bin")
-        .join("self-contained");
+    let target_bin_dir =
+        plat_root.join("lib").join("rustlib").join(target).join("bin").join("self-contained");
     fs::create_dir_all(&target_bin_dir).expect("creating target_bin_dir failed");
     for src in target_tools {
         builder.copy_link_to_folder(&src, &target_bin_dir);
@@ -295,12 +291,8 @@ fn make_win_dist(
     );
 
     //Copy platform libs to platform-specific lib directory
-    let target_lib_dir = plat_root
-        .join("lib")
-        .join("rustlib")
-        .join(target.triple)
-        .join("lib")
-        .join("self-contained");
+    let target_lib_dir =
+        plat_root.join("lib").join("rustlib").join(target).join("lib").join("self-contained");
     fs::create_dir_all(&target_lib_dir).expect("creating target_lib_dir failed");
     for src in target_libs {
         builder.copy_link_to_folder(&src, &target_lib_dir);
@@ -450,7 +442,7 @@ fn prepare_image(builder: &Builder<'_>, compiler: Compiler, image: &Path) {
             // component for now.
             maybe_install_llvm_runtime(builder, host, image);
 
-            let dst_dir = image.join("lib/rustlib").join(&*host.triple).join("bin");
+            let dst_dir = image.join("lib/rustlib").join(host).join("bin");
             t!(fs::create_dir_all(&dst_dir));
 
             // Copy over lld if it's there
@@ -607,7 +599,7 @@ fn verify_uefi_rlib_format(builder: &Builder<'_>, target: TargetSelection, stamp
 
 /// Copy stamped files into an image's `target/lib` directory.
 fn copy_target_libs(builder: &Builder<'_>, target: TargetSelection, image: &Path, stamp: &Path) {
-    let dst = image.join("lib/rustlib").join(target.triple).join("lib");
+    let dst = image.join("lib/rustlib").join(target).join("lib");
     let self_contained_dst = dst.join("self-contained");
     t!(fs::create_dir_all(&dst));
     t!(fs::create_dir_all(&self_contained_dst));
@@ -769,7 +761,7 @@ fn run(self, builder: &Builder<'_>) -> Option<GeneratedTarball> {
 
         let src = builder
             .stage_out(compiler, Mode::Std)
-            .join(target.triple)
+            .join(target)
             .join(builder.cargo_dir())
             .join("deps")
             .join("save-analysis");
@@ -1509,7 +1501,7 @@ macro_rules! add_component {
         tarballs.push(builder.ensure(Rustc { compiler: builder.compiler(stage, target) }));
         tarballs.push(builder.ensure(Std { compiler, target }).expect("missing std"));
 
-        if target.ends_with("windows-gnu") {
+        if target.is_windows_gnu() {
             tarballs.push(builder.ensure(Mingw { host: target }).expect("missing mingw"));
         }
 
@@ -1683,7 +1675,7 @@ fn filter(contents: &str, marker: &str) -> String {
                     prepare(tool);
                 }
             }
-            if target.ends_with("windows-gnu") {
+            if target.is_windows_gnu() {
                 prepare("rust-mingw");
             }
 
@@ -1830,7 +1822,7 @@ fn filter(contents: &str, marker: &str) -> String {
                 .arg("-t")
                 .arg(etc.join("msi/remove-duplicates.xsl"))
                 .run(builder);
-            if target.ends_with("windows-gnu") {
+            if target.is_windows_gnu() {
                 command(&heat)
                     .current_dir(&exe)
                     .arg("dir")
@@ -1876,7 +1868,7 @@ fn filter(contents: &str, marker: &str) -> String {
                 if built_tools.contains("miri") {
                     cmd.arg("-dMiriDir=miri");
                 }
-                if target.ends_with("windows-gnu") {
+                if target.is_windows_gnu() {
                     cmd.arg("-dGccDir=rust-mingw");
                 }
                 cmd.run(builder);
@@ -1901,7 +1893,7 @@ fn filter(contents: &str, marker: &str) -> String {
             }
             candle("AnalysisGroup.wxs".as_ref());
 
-            if target.ends_with("windows-gnu") {
+            if target.is_windows_gnu() {
                 candle("GccGroup.wxs".as_ref());
             }
 
@@ -1941,7 +1933,7 @@ fn filter(contents: &str, marker: &str) -> String {
                 cmd.arg("DocsGroup.wixobj");
             }
 
-            if target.ends_with("windows-gnu") {
+            if target.is_windows_gnu() {
                 cmd.arg("GccGroup.wixobj");
             }
             // ICE57 wrongly complains about the shortcuts
@@ -1973,7 +1965,7 @@ fn add_env(builder: &Builder<'_>, cmd: &mut BootstrapCommand, target: TargetSele
 
     if target.contains("windows-gnullvm") {
         cmd.env("CFG_MINGW", "1").env("CFG_ABI", "LLVM");
-    } else if target.contains("windows-gnu") {
+    } else if target.is_windows_gnu() {
         cmd.env("CFG_MINGW", "1").env("CFG_ABI", "GNU");
     } else {
         cmd.env("CFG_MINGW", "0").env("CFG_ABI", "MSVC");
@@ -2087,7 +2079,7 @@ fn maybe_install_llvm(
 
 /// Maybe add libLLVM.so to the target lib-dir for linking.
 pub fn maybe_install_llvm_target(builder: &Builder<'_>, target: TargetSelection, sysroot: &Path) {
-    let dst_libdir = sysroot.join("lib/rustlib").join(&*target.triple).join("lib");
+    let dst_libdir = sysroot.join("lib/rustlib").join(target).join("lib");
     // We do not need to copy LLVM files into the sysroot if it is not
     // dynamically linked; it is already included into librustc_llvm
     // statically.
diff --git a/src/bootstrap/src/core/build_steps/doc.rs b/src/bootstrap/src/core/build_steps/doc.rs
index 2cd5db706c2..301633559fe 100644
--- a/src/bootstrap/src/core/build_steps/doc.rs
+++ b/src/bootstrap/src/core/build_steps/doc.rs
@@ -699,13 +699,12 @@ fn doc_std(
     let compiler = builder.compiler(stage, builder.config.build);
 
     let target_doc_dir_name = if format == DocumentationFormat::Json { "json-doc" } else { "doc" };
-    let target_dir =
-        builder.stage_out(compiler, Mode::Std).join(target.triple).join(target_doc_dir_name);
+    let target_dir = builder.stage_out(compiler, Mode::Std).join(target).join(target_doc_dir_name);
 
     // This is directory where the compiler will place the output of the command.
     // We will then copy the files from this directory into the final `out` directory, the specified
     // as a function parameter.
-    let out_dir = target_dir.join(target.triple).join("doc");
+    let out_dir = target_dir.join(target).join("doc");
 
     let mut cargo =
         builder::Cargo::new(builder, compiler, Mode::Std, SourceType::InTree, target, Kind::Doc);
@@ -846,7 +845,7 @@ fn run(self, builder: &Builder<'_>) {
 
         let mut to_open = None;
 
-        let out_dir = builder.stage_out(compiler, Mode::Rustc).join(target.triple).join("doc");
+        let out_dir = builder.stage_out(compiler, Mode::Rustc).join(target).join("doc");
         for krate in &*self.crates {
             // Create all crate output directories first to make sure rustdoc uses
             // relative links.
@@ -992,7 +991,7 @@ fn run(self, builder: &Builder<'_>) {
                 // see https://github.com/rust-lang/rust/pull/122066#issuecomment-1983049222
                 // cargo.rustdocflag("--generate-link-to-definition");
 
-                let out_dir = builder.stage_out(compiler, Mode::ToolRustc).join(target.triple).join("doc");
+                let out_dir = builder.stage_out(compiler, Mode::ToolRustc).join(target).join("doc");
                 $(for krate in $crates {
                     let dir_name = krate.replace("-", "_");
                     t!(fs::create_dir_all(out_dir.join(&*dir_name)));
diff --git a/src/bootstrap/src/core/build_steps/test.rs b/src/bootstrap/src/core/build_steps/test.rs
index 6ed001d8fd5..cc01afd4c18 100644
--- a/src/bootstrap/src/core/build_steps/test.rs
+++ b/src/bootstrap/src/core/build_steps/test.rs
@@ -149,7 +149,7 @@ fn run(self, builder: &Builder<'_>) {
         let _guard =
             builder.msg(Kind::Test, compiler.stage, "Linkcheck", bootstrap_host, bootstrap_host);
         let _time = helpers::timeit(builder);
-        linkchecker.delay_failure().arg(builder.out.join(host.triple).join("doc")).run(builder);
+        linkchecker.delay_failure().arg(builder.out.join(host).join("doc")).run(builder);
     }
 
     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
@@ -435,7 +435,7 @@ pub fn build_miri_sysroot(
         compiler: Compiler,
         target: TargetSelection,
     ) -> PathBuf {
-        let miri_sysroot = builder.out.join(compiler.host.triple).join("miri-sysroot");
+        let miri_sysroot = builder.out.join(compiler.host).join("miri-sysroot");
         let mut cargo = builder::Cargo::new(
             builder,
             compiler,
@@ -1115,7 +1115,7 @@ fn make_run(run: RunConfig<'_>) {
 }
 
 fn testdir(builder: &Builder<'_>, host: TargetSelection) -> PathBuf {
-    builder.out.join(host.triple).join("test")
+    builder.out.join(host).join("test")
 }
 
 macro_rules! default_test {
@@ -1817,7 +1817,7 @@ fn run(self, builder: &Builder<'_>) {
 
         let mut flags = if is_rustdoc { Vec::new() } else { vec!["-Crpath".to_string()] };
         flags.push(format!("-Cdebuginfo={}", builder.config.rust_debuginfo_level_tests));
-        flags.extend(builder.config.cmd.rustc_args().iter().map(|s| s.to_string()));
+        flags.extend(builder.config.cmd.compiletest_rustc_args().iter().map(|s| s.to_string()));
 
         if suite != "mir-opt" {
             if let Some(linker) = builder.linker(target) {
@@ -2685,7 +2685,7 @@ fn run(self, builder: &Builder<'_>) {
                     if builder.download_rustc() && compiler.stage > 0 {
                         let sysroot = builder
                             .out
-                            .join(compiler.host.triple)
+                            .join(compiler.host)
                             .join(format!("stage{}-test-sysroot", compiler.stage));
                         cargo.env("RUSTC_SYSROOT", sysroot);
                     }
diff --git a/src/bootstrap/src/core/builder.rs b/src/bootstrap/src/core/builder.rs
index ccdeb442af4..454cc20d155 100644
--- a/src/bootstrap/src/core/builder.rs
+++ b/src/bootstrap/src/core/builder.rs
@@ -1171,7 +1171,7 @@ fn run(self, builder: &Builder<'_>) -> PathBuf {
                     .sysroot(self.compiler)
                     .join(lib)
                     .join("rustlib")
-                    .join(self.target.triple)
+                    .join(self.target)
                     .join("lib");
                 // Avoid deleting the rustlib/ directory we just copied
                 // (in `impl Step for Sysroot`).
@@ -1254,7 +1254,7 @@ pub fn rustc_lib_paths(&self, compiler: Compiler) -> Vec<PathBuf> {
 
         // Ensure that the downloaded LLVM libraries can be found.
         if self.config.llvm_from_ci {
-            let ci_llvm_lib = self.out.join(&*compiler.host.triple).join("ci-llvm").join("lib");
+            let ci_llvm_lib = self.out.join(compiler.host).join("ci-llvm").join("lib");
             dylib_dirs.push(ci_llvm_lib);
         }
 
@@ -1504,9 +1504,9 @@ fn cargo(
                 Mode::Rustc | Mode::ToolRustc => self.compiler_doc_out(target),
                 Mode::Std => {
                     if self.config.cmd.json() {
-                        out_dir.join(target.triple).join("json-doc")
+                        out_dir.join(target).join("json-doc")
                     } else {
-                        out_dir.join(target.triple).join("doc")
+                        out_dir.join(target).join("doc")
                     }
                 }
                 _ => panic!("doc mode {mode:?} not expected"),
@@ -2226,11 +2226,6 @@ fn cargo(
             rustdocflags.arg("--cfg=parallel_compiler");
         }
 
-        // Pass the value of `--rustc-args` from test command. If it's not a test command, this won't set anything.
-        self.config.cmd.rustc_args().iter().for_each(|v| {
-            rustflags.arg(v);
-        });
-
         Cargo {
             command: cargo,
             compiler,
diff --git a/src/bootstrap/src/core/builder/tests.rs b/src/bootstrap/src/core/builder/tests.rs
index e06df65c1bc..c554684d5a7 100644
--- a/src/bootstrap/src/core/builder/tests.rs
+++ b/src/bootstrap/src/core/builder/tests.rs
@@ -633,7 +633,7 @@ fn test_with_no_doc_stage0() {
         config.paths = vec!["library/std".into()];
         config.cmd = Subcommand::Test {
             test_args: vec![],
-            rustc_args: vec![],
+            compiletest_rustc_args: vec![],
             no_fail_fast: false,
             no_doc: true,
             doc: false,
@@ -704,7 +704,7 @@ fn test_docs() {
         let mut config = configure(&["A-A"], &["A-A"]);
         config.cmd = Subcommand::Test {
             test_args: vec![],
-            rustc_args: vec![],
+            compiletest_rustc_args: vec![],
             no_fail_fast: false,
             doc: true,
             no_doc: false,
diff --git a/src/bootstrap/src/core/config/config.rs b/src/bootstrap/src/core/config/config.rs
index 35ee4a29c68..36de8324f67 100644
--- a/src/bootstrap/src/core/config/config.rs
+++ b/src/bootstrap/src/core/config/config.rs
@@ -514,6 +514,10 @@ pub fn is_windows(&self) -> bool {
         self.contains("windows")
     }
 
+    pub fn is_windows_gnu(&self) -> bool {
+        self.ends_with("windows-gnu")
+    }
+
     /// Path to the file defining the custom target, if any.
     pub fn filepath(&self) -> Option<&Path> {
         self.file.as_ref().map(Path::new)
@@ -542,6 +546,14 @@ fn eq(&self, other: &&str) -> bool {
     }
 }
 
+// Targets are often used as directory names throughout bootstrap.
+// This impl makes it more ergonomics to use them as such.
+impl AsRef<Path> for TargetSelection {
+    fn as_ref(&self) -> &Path {
+        self.triple.as_ref()
+    }
+}
+
 /// Per-target configuration stored in the global configuration structure.
 #[derive(Debug, Default, Clone, PartialEq, Eq)]
 pub struct Target {
@@ -1469,7 +1481,7 @@ fn get_table(option: &str) -> Result<TomlConfig, toml::de::Error> {
             config.download_beta_toolchain();
             config
                 .out
-                .join(config.build.triple)
+                .join(config.build)
                 .join("stage0")
                 .join("bin")
                 .join(exe("rustc", config.build))
@@ -1484,7 +1496,7 @@ fn get_table(option: &str) -> Result<TomlConfig, toml::de::Error> {
             config.download_beta_toolchain();
             config
                 .out
-                .join(config.build.triple)
+                .join(config.build)
                 .join("stage0")
                 .join("bin")
                 .join(exe("cargo", config.build))
@@ -2277,13 +2289,13 @@ pub fn libdir_relative(&self) -> Option<&Path> {
     /// The absolute path to the downloaded LLVM artifacts.
     pub(crate) fn ci_llvm_root(&self) -> PathBuf {
         assert!(self.llvm_from_ci);
-        self.out.join(&*self.build.triple).join("ci-llvm")
+        self.out.join(self.build).join("ci-llvm")
     }
 
     /// Directory where the extracted `rustc-dev` component is stored.
     pub(crate) fn ci_rustc_dir(&self) -> PathBuf {
         assert!(self.download_rustc());
-        self.out.join(self.build.triple).join("ci-rustc")
+        self.out.join(self.build).join("ci-rustc")
     }
 
     /// Determine whether llvm should be linked dynamically.
diff --git a/src/bootstrap/src/core/config/flags.rs b/src/bootstrap/src/core/config/flags.rs
index 3948fe0d98c..c3f17402814 100644
--- a/src/bootstrap/src/core/config/flags.rs
+++ b/src/bootstrap/src/core/config/flags.rs
@@ -357,9 +357,9 @@ pub enum Subcommand {
         /// extra arguments to be passed for the test tool being used
         /// (e.g. libtest, compiletest or rustdoc)
         test_args: Vec<String>,
-        /// extra options to pass the compiler when running tests
+        /// extra options to pass the compiler when running compiletest tests
         #[arg(long, value_name = "ARGS", allow_hyphen_values(true))]
-        rustc_args: Vec<String>,
+        compiletest_rustc_args: Vec<String>,
         #[arg(long)]
         /// do not run doc tests
         no_doc: bool,
@@ -402,9 +402,6 @@ pub enum Subcommand {
         /// extra arguments to be passed for the test tool being used
         /// (e.g. libtest, compiletest or rustdoc)
         test_args: Vec<String>,
-        /// extra options to pass the compiler when running tests
-        #[arg(long, value_name = "ARGS", allow_hyphen_values(true))]
-        rustc_args: Vec<String>,
         #[arg(long)]
         /// do not run doc tests
         no_doc: bool,
@@ -509,10 +506,10 @@ pub fn kind(&self) -> Kind {
         }
     }
 
-    pub fn rustc_args(&self) -> Vec<&str> {
+    pub fn compiletest_rustc_args(&self) -> Vec<&str> {
         match *self {
-            Subcommand::Test { ref rustc_args, .. } | Subcommand::Miri { ref rustc_args, .. } => {
-                rustc_args.iter().flat_map(|s| s.split_whitespace()).collect()
+            Subcommand::Test { ref compiletest_rustc_args, .. } => {
+                compiletest_rustc_args.iter().flat_map(|s| s.split_whitespace()).collect()
             }
             _ => vec![],
         }
diff --git a/src/bootstrap/src/core/download.rs b/src/bootstrap/src/core/download.rs
index 4d1aea3cd95..8131666fcb2 100644
--- a/src/bootstrap/src/core/download.rs
+++ b/src/bootstrap/src/core/download.rs
@@ -379,7 +379,7 @@ pub(crate) fn download_clippy(&self) -> PathBuf {
         let version = &self.stage0_metadata.compiler.version;
         let host = self.build;
 
-        let bin_root = self.out.join(host.triple).join("stage0");
+        let bin_root = self.out.join(host).join("stage0");
         let clippy_stamp = bin_root.join(".clippy-stamp");
         let cargo_clippy = bin_root.join("bin").join(exe("cargo-clippy", host));
         if cargo_clippy.exists() && !program_out_of_date(&clippy_stamp, date) {
@@ -412,7 +412,7 @@ pub(crate) fn maybe_download_rustfmt(&self) -> Option<PathBuf> {
         let channel = format!("{version}-{date}");
 
         let host = self.build;
-        let bin_root = self.out.join(host.triple).join("rustfmt");
+        let bin_root = self.out.join(host).join("rustfmt");
         let rustfmt_path = bin_root.join("bin").join(exe("rustfmt", host));
         let rustfmt_stamp = bin_root.join(".rustfmt-stamp");
         if rustfmt_path.exists() && !program_out_of_date(&rustfmt_stamp, &channel) {
@@ -519,7 +519,7 @@ fn download_toolchain(
         extra_components: &[&str],
         download_component: fn(&Config, String, &str, &str),
     ) {
-        let host = self.build.triple;
+        let host = self.build;
         let bin_root = self.out.join(host).join(sysroot);
         let rustc_stamp = bin_root.join(".rustc-stamp");
 
@@ -592,7 +592,7 @@ fn download_component(
             t!(fs::create_dir_all(&cache_dir));
         }
 
-        let bin_root = self.out.join(self.build.triple).join(destination);
+        let bin_root = self.out.join(self.build).join(destination);
         let tarball = cache_dir.join(&filename);
         let (base_url, url, should_verify) = match mode {
             DownloadSource::CI => {
diff --git a/src/bootstrap/src/lib.rs b/src/bootstrap/src/lib.rs
index e8a61ab4cf5..bfd0e42acfd 100644
--- a/src/bootstrap/src/lib.rs
+++ b/src/bootstrap/src/lib.rs
@@ -452,7 +452,7 @@ pub fn new(mut config: Config) -> Build {
         }
 
         // Make a symbolic link so we can use a consistent directory in the documentation.
-        let build_triple = build.out.join(build.build.triple);
+        let build_triple = build.out.join(build.build);
         t!(fs::create_dir_all(&build_triple));
         let host = build.out.join("host");
         if host.is_symlink() {
@@ -807,10 +807,7 @@ fn cargo_dir(&self) -> &'static str {
     }
 
     fn tools_dir(&self, compiler: Compiler) -> PathBuf {
-        let out = self
-            .out
-            .join(&*compiler.host.triple)
-            .join(format!("stage{}-tools-bin", compiler.stage));
+        let out = self.out.join(compiler.host).join(format!("stage{}-tools-bin", compiler.stage));
         t!(fs::create_dir_all(&out));
         out
     }
@@ -827,14 +824,14 @@ fn stage_out(&self, compiler: Compiler, mode: Mode) -> PathBuf {
             Mode::ToolBootstrap => "-bootstrap-tools",
             Mode::ToolStd | Mode::ToolRustc => "-tools",
         };
-        self.out.join(&*compiler.host.triple).join(format!("stage{}{}", compiler.stage, suffix))
+        self.out.join(compiler.host).join(format!("stage{}{}", compiler.stage, suffix))
     }
 
     /// Returns the root output directory for all Cargo output in a given stage,
     /// running a particular compiler, whether or not we're building the
     /// standard library, and targeting the specified architecture.
     fn cargo_out(&self, compiler: Compiler, mode: Mode, target: TargetSelection) -> PathBuf {
-        self.stage_out(compiler, mode).join(&*target.triple).join(self.cargo_dir())
+        self.stage_out(compiler, mode).join(target).join(self.cargo_dir())
     }
 
     /// Root output directory of LLVM for `target`
@@ -845,36 +842,36 @@ fn llvm_out(&self, target: TargetSelection) -> PathBuf {
         if self.config.llvm_from_ci && self.config.build == target {
             self.config.ci_llvm_root()
         } else {
-            self.out.join(&*target.triple).join("llvm")
+            self.out.join(target).join("llvm")
         }
     }
 
     fn lld_out(&self, target: TargetSelection) -> PathBuf {
-        self.out.join(&*target.triple).join("lld")
+        self.out.join(target).join("lld")
     }
 
     /// Output directory for all documentation for a target
     fn doc_out(&self, target: TargetSelection) -> PathBuf {
-        self.out.join(&*target.triple).join("doc")
+        self.out.join(target).join("doc")
     }
 
     /// Output directory for all JSON-formatted documentation for a target
     fn json_doc_out(&self, target: TargetSelection) -> PathBuf {
-        self.out.join(&*target.triple).join("json-doc")
+        self.out.join(target).join("json-doc")
     }
 
     fn test_out(&self, target: TargetSelection) -> PathBuf {
-        self.out.join(&*target.triple).join("test")
+        self.out.join(target).join("test")
     }
 
     /// Output directory for all documentation for a target
     fn compiler_doc_out(&self, target: TargetSelection) -> PathBuf {
-        self.out.join(&*target.triple).join("compiler-doc")
+        self.out.join(target).join("compiler-doc")
     }
 
     /// Output directory for some generated md crate documentation for a target (temporary)
     fn md_doc_out(&self, target: TargetSelection) -> PathBuf {
-        self.out.join(&*target.triple).join("md-doc")
+        self.out.join(target).join("md-doc")
     }
 
     /// Returns `true` if this is an external version of LLVM not managed by bootstrap.
@@ -954,7 +951,7 @@ fn llvm_filecheck(&self, target: TargetSelection) -> PathBuf {
 
     /// Directory for libraries built from C/C++ code and shared between stages.
     fn native_dir(&self, target: TargetSelection) -> PathBuf {
-        self.out.join(&*target.triple).join("native")
+        self.out.join(target).join("native")
     }
 
     /// Root output directory for rust_test_helpers library compiled for
diff --git a/src/bootstrap/src/utils/change_tracker.rs b/src/bootstrap/src/utils/change_tracker.rs
index 84dac25188e..c629f04c00e 100644
--- a/src/bootstrap/src/utils/change_tracker.rs
+++ b/src/bootstrap/src/utils/change_tracker.rs
@@ -225,4 +225,9 @@ pub fn human_readable_changes(changes: &[ChangeInfo]) -> String {
         severity: ChangeSeverity::Info,
         summary: "New option `llvm.libzstd` to control whether llvm is built with zstd support.",
     },
+    ChangeInfo {
+        change_id: 128841,
+        severity: ChangeSeverity::Warning,
+        summary: "./x test --rustc-args was renamed to --compiletest-rustc-args as it only applies there. ./x miri --rustc-args was also removed.",
+    },
 ];
diff --git a/src/ci/docker/scripts/x86_64-gnu-llvm.sh b/src/ci/docker/scripts/x86_64-gnu-llvm.sh
index b3921f11421..98290f5a72c 100755
--- a/src/ci/docker/scripts/x86_64-gnu-llvm.sh
+++ b/src/ci/docker/scripts/x86_64-gnu-llvm.sh
@@ -18,9 +18,9 @@ if [[ -z "${PR_CI_JOB}" ]]; then
     # compiler, and is sensitive to the addition of new flags.
     ../x.py --stage 1 test tests/ui-fulldeps
 
-    # The tests are run a second time with the size optimizations enabled.
-    ../x.py --stage 1 test library/std library/alloc library/core \
-        --rustc-args "--cfg feature=\"optimize_for_size\""
+    # Rebuild the stdlib with the size optimizations enabled and run tests again.
+    RUSTFLAGS_NOT_BOOTSTRAP="--cfg feature=\"optimize_for_size\"" ../x.py --stage 1 test \
+        library/std library/alloc library/core
 fi
 
 # NOTE: intentionally uses all of `x.py`, `x`, and `x.ps1` to make sure they all work on Linux.
diff --git a/src/etc/completions/x.py.fish b/src/etc/completions/x.py.fish
index 805fc8aa8cc..297dc11cd61 100644
--- a/src/etc/completions/x.py.fish
+++ b/src/etc/completions/x.py.fish
@@ -266,7 +266,7 @@ complete -c x.py -n "__fish_seen_subcommand_from doc" -l enable-bolt-settings -d
 complete -c x.py -n "__fish_seen_subcommand_from doc" -l skip-stage0-validation -d 'Skip stage0 compiler validation'
 complete -c x.py -n "__fish_seen_subcommand_from doc" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x.py -n "__fish_seen_subcommand_from test" -l test-args -d 'extra arguments to be passed for the test tool being used (e.g. libtest, compiletest or rustdoc)' -r
-complete -c x.py -n "__fish_seen_subcommand_from test" -l rustc-args -d 'extra options to pass the compiler when running tests' -r
+complete -c x.py -n "__fish_seen_subcommand_from test" -l compiletest-rustc-args -d 'extra options to pass the compiler when running compiletest tests' -r
 complete -c x.py -n "__fish_seen_subcommand_from test" -l extra-checks -d 'comma-separated list of other files types to check (accepts py, py:lint, py:fmt, shell)' -r
 complete -c x.py -n "__fish_seen_subcommand_from test" -l compare-mode -d 'mode describing what file the actual ui output will be compared to' -r
 complete -c x.py -n "__fish_seen_subcommand_from test" -l pass -d 'force {check,build,run}-pass tests to this mode' -r
@@ -313,7 +313,6 @@ complete -c x.py -n "__fish_seen_subcommand_from test" -l enable-bolt-settings -
 complete -c x.py -n "__fish_seen_subcommand_from test" -l skip-stage0-validation -d 'Skip stage0 compiler validation'
 complete -c x.py -n "__fish_seen_subcommand_from test" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x.py -n "__fish_seen_subcommand_from miri" -l test-args -d 'extra arguments to be passed for the test tool being used (e.g. libtest, compiletest or rustdoc)' -r
-complete -c x.py -n "__fish_seen_subcommand_from miri" -l rustc-args -d 'extra options to pass the compiler when running tests' -r
 complete -c x.py -n "__fish_seen_subcommand_from miri" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_seen_subcommand_from miri" -l build-dir -d 'Build directory, overrides `build.build-dir` in `config.toml`' -r -f -a "(__fish_complete_directories)"
 complete -c x.py -n "__fish_seen_subcommand_from miri" -l build -d 'build target of the stage0 compiler' -r -f
diff --git a/src/etc/completions/x.py.ps1 b/src/etc/completions/x.py.ps1
index ce590d2fa48..4b424471a26 100644
--- a/src/etc/completions/x.py.ps1
+++ b/src/etc/completions/x.py.ps1
@@ -338,7 +338,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
         }
         'x.py;test' {
             [CompletionResult]::new('--test-args', 'test-args', [CompletionResultType]::ParameterName, 'extra arguments to be passed for the test tool being used (e.g. libtest, compiletest or rustdoc)')
-            [CompletionResult]::new('--rustc-args', 'rustc-args', [CompletionResultType]::ParameterName, 'extra options to pass the compiler when running tests')
+            [CompletionResult]::new('--compiletest-rustc-args', 'compiletest-rustc-args', [CompletionResultType]::ParameterName, 'extra options to pass the compiler when running compiletest tests')
             [CompletionResult]::new('--extra-checks', 'extra-checks', [CompletionResultType]::ParameterName, 'comma-separated list of other files types to check (accepts py, py:lint, py:fmt, shell)')
             [CompletionResult]::new('--compare-mode', 'compare-mode', [CompletionResultType]::ParameterName, 'mode describing what file the actual ui output will be compared to')
             [CompletionResult]::new('--pass', 'pass', [CompletionResultType]::ParameterName, 'force {check,build,run}-pass tests to this mode')
@@ -392,7 +392,6 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
         }
         'x.py;miri' {
             [CompletionResult]::new('--test-args', 'test-args', [CompletionResultType]::ParameterName, 'extra arguments to be passed for the test tool being used (e.g. libtest, compiletest or rustdoc)')
-            [CompletionResult]::new('--rustc-args', 'rustc-args', [CompletionResultType]::ParameterName, 'extra options to pass the compiler when running tests')
             [CompletionResult]::new('--config', 'config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', 'build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `config.toml`')
             [CompletionResult]::new('--build', 'build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
diff --git a/src/etc/completions/x.py.sh b/src/etc/completions/x.py.sh
index a4234905476..60ba8d3ba70 100644
--- a/src/etc/completions/x.py.sh
+++ b/src/etc/completions/x.py.sh
@@ -1300,7 +1300,7 @@ _x.py() {
             return 0
             ;;
         x.py__miri)
-            opts="-v -i -j -h --no-fail-fast --test-args --rustc-args --no-doc --doc --verbose --incremental --config --build-dir --build --host --target --exclude --skip --include-default-paths --rustc-error-format --on-fail --dry-run --dump-bootstrap-shims --stage --keep-stage --keep-stage-std --src --jobs --warnings --error-format --json-output --color --bypass-bootstrap-lock --llvm-skip-rebuild --rust-profile-generate --rust-profile-use --llvm-profile-use --llvm-profile-generate --enable-bolt-settings --skip-stage0-validation --reproducible-artifact --set --help [PATHS]... [ARGS]..."
+            opts="-v -i -j -h --no-fail-fast --test-args --no-doc --doc --verbose --incremental --config --build-dir --build --host --target --exclude --skip --include-default-paths --rustc-error-format --on-fail --dry-run --dump-bootstrap-shims --stage --keep-stage --keep-stage-std --src --jobs --warnings --error-format --json-output --color --bypass-bootstrap-lock --llvm-skip-rebuild --rust-profile-generate --rust-profile-use --llvm-profile-use --llvm-profile-generate --enable-bolt-settings --skip-stage0-validation --reproducible-artifact --set --help [PATHS]... [ARGS]..."
             if [[ ${cur} == -* || ${COMP_CWORD} -eq 2 ]] ; then
                 COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
                 return 0
@@ -1310,10 +1310,6 @@ _x.py() {
                     COMPREPLY=($(compgen -f "${cur}"))
                     return 0
                     ;;
-                --rustc-args)
-                    COMPREPLY=($(compgen -f "${cur}"))
-                    return 0
-                    ;;
                 --config)
                     COMPREPLY=($(compgen -f "${cur}"))
                     return 0
@@ -1862,7 +1858,7 @@ _x.py() {
             return 0
             ;;
         x.py__test)
-            opts="-v -i -j -h --no-fail-fast --test-args --rustc-args --no-doc --doc --bless --extra-checks --force-rerun --only-modified --compare-mode --pass --run --rustfix-coverage --verbose --incremental --config --build-dir --build --host --target --exclude --skip --include-default-paths --rustc-error-format --on-fail --dry-run --dump-bootstrap-shims --stage --keep-stage --keep-stage-std --src --jobs --warnings --error-format --json-output --color --bypass-bootstrap-lock --llvm-skip-rebuild --rust-profile-generate --rust-profile-use --llvm-profile-use --llvm-profile-generate --enable-bolt-settings --skip-stage0-validation --reproducible-artifact --set --help [PATHS]... [ARGS]..."
+            opts="-v -i -j -h --no-fail-fast --test-args --compiletest-rustc-args --no-doc --doc --bless --extra-checks --force-rerun --only-modified --compare-mode --pass --run --rustfix-coverage --verbose --incremental --config --build-dir --build --host --target --exclude --skip --include-default-paths --rustc-error-format --on-fail --dry-run --dump-bootstrap-shims --stage --keep-stage --keep-stage-std --src --jobs --warnings --error-format --json-output --color --bypass-bootstrap-lock --llvm-skip-rebuild --rust-profile-generate --rust-profile-use --llvm-profile-use --llvm-profile-generate --enable-bolt-settings --skip-stage0-validation --reproducible-artifact --set --help [PATHS]... [ARGS]..."
             if [[ ${cur} == -* || ${COMP_CWORD} -eq 2 ]] ; then
                 COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
                 return 0
@@ -1872,7 +1868,7 @@ _x.py() {
                     COMPREPLY=($(compgen -f "${cur}"))
                     return 0
                     ;;
-                --rustc-args)
+                --compiletest-rustc-args)
                     COMPREPLY=($(compgen -f "${cur}"))
                     return 0
                     ;;
diff --git a/src/etc/completions/x.py.zsh b/src/etc/completions/x.py.zsh
index fc8be4f7881..688f692da24 100644
--- a/src/etc/completions/x.py.zsh
+++ b/src/etc/completions/x.py.zsh
@@ -337,7 +337,7 @@ _arguments "${_arguments_options[@]}" \
 (test)
 _arguments "${_arguments_options[@]}" \
 '*--test-args=[extra arguments to be passed for the test tool being used (e.g. libtest, compiletest or rustdoc)]:ARGS: ' \
-'*--rustc-args=[extra options to pass the compiler when running tests]:ARGS: ' \
+'*--compiletest-rustc-args=[extra options to pass the compiler when running compiletest tests]:ARGS: ' \
 '--extra-checks=[comma-separated list of other files types to check (accepts py, py\:lint, py\:fmt, shell)]:EXTRA_CHECKS: ' \
 '--compare-mode=[mode describing what file the actual ui output will be compared to]:COMPARE MODE: ' \
 '--pass=[force {check,build,run}-pass tests to this mode]:check | build | run: ' \
@@ -393,7 +393,6 @@ _arguments "${_arguments_options[@]}" \
 (miri)
 _arguments "${_arguments_options[@]}" \
 '*--test-args=[extra arguments to be passed for the test tool being used (e.g. libtest, compiletest or rustdoc)]:ARGS: ' \
-'*--rustc-args=[extra options to pass the compiler when running tests]:ARGS: ' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`config.toml\`]:DIR:_files -/' \
 '--build=[build target of the stage0 compiler]:BUILD:( )' \
diff --git a/src/tools/compiletest/src/runtest.rs b/src/tools/compiletest/src/runtest.rs
index ce6569f5537..59fce44d1c7 100644
--- a/src/tools/compiletest/src/runtest.rs
+++ b/src/tools/compiletest/src/runtest.rs
@@ -3735,15 +3735,14 @@ fn run_rmake_v2_test(&self) {
         }
 
         if self.config.bless {
-            cmd.env("RUSTC_BLESS_TEST", "--bless");
-            // Assume this option is active if the environment variable is "defined", with _any_ value.
-            // As an example, a `Makefile` can use this option by:
+            // If we're running in `--bless` mode, set an environment variable to tell
+            // `run_make_support` to bless snapshot files instead of checking them.
             //
-            //   ifdef RUSTC_BLESS_TEST
-            //       cp "$(TMPDIR)"/actual_something.ext expected_something.ext
-            //   else
-            //       $(DIFF) expected_something.ext "$(TMPDIR)"/actual_something.ext
-            //   endif
+            // The value is this test's source directory, because the support code
+            // will need that path in order to bless the _original_ snapshot files,
+            // not the copies in `rmake_out`.
+            // (See <https://github.com/rust-lang/rust/issues/129038>.)
+            cmd.env("RUSTC_BLESS_TEST", &self.testpaths.file);
         }
 
         if self.config.target.contains("msvc") && !self.config.cc.is_empty() {
diff --git a/src/tools/run-make-support/src/diff/mod.rs b/src/tools/run-make-support/src/diff/mod.rs
index b0ed4d5445c..ee48e373366 100644
--- a/src/tools/run-make-support/src/diff/mod.rs
+++ b/src/tools/run-make-support/src/diff/mod.rs
@@ -112,14 +112,8 @@ pub fn run(&mut self) {
         let (expected_name, actual_name, output, actual) = self.run_common();
 
         if !output.is_empty() {
-            // If we can bless (meaning we have a file to write into and the `RUSTC_BLESS_TEST`
-            // environment variable set), then we write into the file and return.
-            if let Some(ref expected_file) = self.expected_file {
-                if std::env::var("RUSTC_BLESS_TEST").is_ok() {
-                    println!("Blessing `{}`", expected_file.display());
-                    fs::write(expected_file, actual);
-                    return;
-                }
+            if self.maybe_bless_expected_file(&actual) {
+                return;
             }
             panic!(
                 "test failed: `{}` is different from `{}`\n\n{}",
@@ -134,14 +128,8 @@ pub fn run_fail(&mut self) {
         let (expected_name, actual_name, output, actual) = self.run_common();
 
         if output.is_empty() {
-            // If we can bless (meaning we have a file to write into and the `RUSTC_BLESS_TEST`
-            // environment variable set), then we write into the file and return.
-            if let Some(ref expected_file) = self.expected_file {
-                if std::env::var("RUSTC_BLESS_TEST").is_ok() {
-                    println!("Blessing `{}`", expected_file.display());
-                    fs::write(expected_file, actual);
-                    return;
-                }
+            if self.maybe_bless_expected_file(&actual) {
+                return;
             }
             panic!(
                 "test failed: `{}` is not different from `{}`\n\n{}",
@@ -149,4 +137,24 @@ pub fn run_fail(&mut self) {
             )
         }
     }
+
+    /// If we have an expected file to write into, and `RUSTC_BLESS_TEST` is
+    /// set, then write the actual output into the file and return `true`.
+    ///
+    /// We assume that `RUSTC_BLESS_TEST` contains the path to the original test's
+    /// source directory. That lets us bless the original snapshot file in the
+    /// source tree, not the copy in `rmake_out` that we would normally use.
+    fn maybe_bless_expected_file(&self, actual: &str) -> bool {
+        let Some(ref expected_file) = self.expected_file else {
+            return false;
+        };
+        let Ok(bless_dir) = std::env::var("RUSTC_BLESS_TEST") else {
+            return false;
+        };
+
+        let bless_file = Path::new(&bless_dir).join(expected_file);
+        println!("Blessing `{}`", bless_file.display());
+        fs::write(bless_file, actual);
+        true
+    }
 }
diff --git a/tests/assembly/powerpc64-struct-abi.rs b/tests/assembly/powerpc64-struct-abi.rs
new file mode 100644
index 00000000000..9a3540d8b41
--- /dev/null
+++ b/tests/assembly/powerpc64-struct-abi.rs
@@ -0,0 +1,132 @@
+//@ revisions: elfv1-be elfv2-be elfv2-le
+//@ assembly-output: emit-asm
+//@ compile-flags: -O
+//@[elfv1-be] compile-flags: --target powerpc64-unknown-linux-gnu
+//@[elfv1-be] needs-llvm-components: powerpc
+//@[elfv2-be] compile-flags: --target powerpc64-unknown-linux-musl
+//@[elfv2-be] needs-llvm-components: powerpc
+//@[elfv2-le] compile-flags: --target powerpc64le-unknown-linux-gnu
+//@[elfv2-le] needs-llvm-components: powerpc
+//@[elfv1-be] filecheck-flags: --check-prefix be
+//@[elfv2-be] filecheck-flags: --check-prefix be
+
+#![feature(no_core, lang_items)]
+#![no_std]
+#![no_core]
+#![crate_type = "lib"]
+
+#[lang = "sized"]
+trait Sized {}
+
+#[lang = "copy"]
+trait Copy {}
+
+#[lang = "freeze"]
+trait Freeze {}
+
+#[lang = "unpin"]
+trait Unpin {}
+
+impl Copy for u8 {}
+impl Copy for u16 {}
+impl Copy for u32 {}
+impl Copy for FiveU32s {}
+impl Copy for FiveU16s {}
+impl Copy for ThreeU8s {}
+
+#[repr(C)]
+struct FiveU32s(u32, u32, u32, u32, u32);
+
+#[repr(C)]
+struct FiveU16s(u16, u16, u16, u16, u16);
+
+#[repr(C)]
+struct ThreeU8s(u8, u8, u8);
+
+// CHECK-LABEL: read_large
+// be: lwz [[REG1:.*]], 16(4)
+// be-NEXT: stw [[REG1]], 16(3)
+// be-NEXT: ld [[REG2:.*]], 8(4)
+// be-NEXT: ld [[REG3:.*]], 0(4)
+// be-NEXT: std [[REG2]], 8(3)
+// be-NEXT: std [[REG3]], 0(3)
+// elfv2-le: lxvd2x [[REG1:.*]], 0, 4
+// elfv2-le-NEXT: lwz [[REG2:.*]], 16(4)
+// elfv2-le-NEXT: stw [[REG2]], 16(3)
+// elfv2-le-NEXT: stxvd2x [[REG1]], 0, 3
+// CHECK-NEXT: blr
+#[no_mangle]
+extern "C" fn read_large(x: &FiveU32s) -> FiveU32s {
+    *x
+}
+
+// CHECK-LABEL: read_medium
+// elfv1-be: lhz [[REG1:.*]], 8(4)
+// elfv1-be-NEXT: ld [[REG2:.*]], 0(4)
+// elfv1-be-NEXT: sth [[REG1]], 8(3)
+// elfv1-be-NEXT: std [[REG2]], 0(3)
+// elfv2-be: lhz [[REG1:.*]], 8(3)
+// elfv2-be-NEXT: ld 3, 0(3)
+// elfv2-be-NEXT: sldi 4, [[REG1]], 48
+// elfv2-le: ld [[REG1:.*]], 0(3)
+// elfv2-le-NEXT: lhz 4, 8(3)
+// elfv2-le-NEXT: mr 3, [[REG1]]
+// CHECK-NEXT: blr
+#[no_mangle]
+extern "C" fn read_medium(x: &FiveU16s) -> FiveU16s {
+    *x
+}
+
+// CHECK-LABEL: read_small
+// elfv1-be: lbz [[REG1:.*]], 2(4)
+// elfv1-be-NEXT: lhz [[REG2:.*]], 0(4)
+// elfv1-be-NEXT: stb [[REG1]], 2(3)
+// elfv1-be-NEXT: sth [[REG2]], 0(3)
+// elfv2-be: lhz [[REG1:.*]], 0(3)
+// elfv2-be-NEXT: lbz 3, 2(3)
+// elfv2-be-NEXT: rldimi 3, [[REG1]], 8, 0
+// elfv2-le: lbz [[REG1:.*]], 2(3)
+// elfv2-le-NEXT: lhz 3, 0(3)
+// elfv2-le-NEXT: rldimi 3, [[REG1]], 16, 0
+// CHECK-NEXT: blr
+#[no_mangle]
+extern "C" fn read_small(x: &ThreeU8s) -> ThreeU8s {
+    *x
+}
+
+// CHECK-LABEL: write_large
+// CHECK: std 3, 0(6)
+// be-NEXT: rldicl [[REG1:.*]], 5, 32, 32
+// CHECK-NEXT: std 4, 8(6)
+// be-NEXT: stw [[REG1]], 16(6)
+// elfv2-le-NEXT: stw 5, 16(6)
+// CHECK-NEXT: blr
+#[no_mangle]
+extern "C" fn write_large(x: FiveU32s, dest: &mut FiveU32s) {
+    *dest = x;
+}
+
+// CHECK-LABEL: write_medium
+// CHECK: std 3, 0(5)
+// be-NEXT: rldicl [[REG1:.*]], 4, 16, 48
+// be-NEXT: sth [[REG1]], 8(5)
+// elfv2-le-NEXT: sth 4, 8(5)
+// CHECK-NEXT: blr
+#[no_mangle]
+extern "C" fn write_medium(x: FiveU16s, dest: &mut FiveU16s) {
+    *dest = x;
+}
+
+// CHECK-LABEL: write_small
+// be: stb 3, 2(4)
+// be-NEXT: srwi [[REG1:.*]], 3, 8
+// be-NEXT: sth [[REG1]], 0(4)
+// The order these instructions are emitted in changed in LLVM 18.
+// elfv2-le-DAG: sth 3, 0(4)
+// elfv2-le-DAG: srwi [[REG1:.*]], 3, 16
+// elfv2-le-NEXT: stb [[REG1]], 2(4)
+// CHECK-NEXT: blr
+#[no_mangle]
+extern "C" fn write_small(x: ThreeU8s, dest: &mut ThreeU8s) {
+    *dest = x;
+}
diff --git a/tests/ui/sanitizer/cfi-assoc-ty-lifetime-issue-123053.rs b/tests/ui/sanitizer/cfi/assoc-ty-lifetime-issue-123053.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-assoc-ty-lifetime-issue-123053.rs
rename to tests/ui/sanitizer/cfi/assoc-ty-lifetime-issue-123053.rs
diff --git a/tests/ui/sanitizer/cfi-async-closures.rs b/tests/ui/sanitizer/cfi/async-closures.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-async-closures.rs
rename to tests/ui/sanitizer/cfi/async-closures.rs
diff --git a/tests/ui/sanitizer/cfi-can-reveal-opaques.rs b/tests/ui/sanitizer/cfi/can-reveal-opaques.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-can-reveal-opaques.rs
rename to tests/ui/sanitizer/cfi/can-reveal-opaques.rs
diff --git a/tests/ui/sanitizer/cfi-canonical-jump-tables-requires-cfi.rs b/tests/ui/sanitizer/cfi/canonical-jump-tables-requires-cfi.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-canonical-jump-tables-requires-cfi.rs
rename to tests/ui/sanitizer/cfi/canonical-jump-tables-requires-cfi.rs
diff --git a/tests/ui/sanitizer/cfi-canonical-jump-tables-requires-cfi.stderr b/tests/ui/sanitizer/cfi/canonical-jump-tables-requires-cfi.stderr
similarity index 100%
rename from tests/ui/sanitizer/cfi-canonical-jump-tables-requires-cfi.stderr
rename to tests/ui/sanitizer/cfi/canonical-jump-tables-requires-cfi.stderr
diff --git a/tests/ui/sanitizer/cfi-closures.rs b/tests/ui/sanitizer/cfi/closures.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-closures.rs
rename to tests/ui/sanitizer/cfi/closures.rs
diff --git a/tests/ui/sanitizer/cfi-complex-receiver.rs b/tests/ui/sanitizer/cfi/complex-receiver.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-complex-receiver.rs
rename to tests/ui/sanitizer/cfi/complex-receiver.rs
diff --git a/tests/ui/sanitizer/cfi-coroutine.rs b/tests/ui/sanitizer/cfi/coroutine.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-coroutine.rs
rename to tests/ui/sanitizer/cfi/coroutine.rs
diff --git a/tests/ui/sanitizer/cfi-drop-in-place.rs b/tests/ui/sanitizer/cfi/drop-in-place.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-drop-in-place.rs
rename to tests/ui/sanitizer/cfi/drop-in-place.rs
diff --git a/tests/ui/sanitizer/cfi-drop-no-principal.rs b/tests/ui/sanitizer/cfi/drop-no-principal.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-drop-no-principal.rs
rename to tests/ui/sanitizer/cfi/drop-no-principal.rs
diff --git a/tests/ui/sanitizer/cfi-fn-ptr.rs b/tests/ui/sanitizer/cfi/fn-ptr.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-fn-ptr.rs
rename to tests/ui/sanitizer/cfi/fn-ptr.rs
diff --git a/tests/ui/sanitizer/cfi-generalize-pointers-attr-cfg.rs b/tests/ui/sanitizer/cfi/generalize-pointers-attr-cfg.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-generalize-pointers-attr-cfg.rs
rename to tests/ui/sanitizer/cfi/generalize-pointers-attr-cfg.rs
diff --git a/tests/ui/sanitizer/cfi-generalize-pointers-requires-cfi.rs b/tests/ui/sanitizer/cfi/generalize-pointers-requires-cfi.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-generalize-pointers-requires-cfi.rs
rename to tests/ui/sanitizer/cfi/generalize-pointers-requires-cfi.rs
diff --git a/tests/ui/sanitizer/cfi-generalize-pointers-requires-cfi.stderr b/tests/ui/sanitizer/cfi/generalize-pointers-requires-cfi.stderr
similarity index 100%
rename from tests/ui/sanitizer/cfi-generalize-pointers-requires-cfi.stderr
rename to tests/ui/sanitizer/cfi/generalize-pointers-requires-cfi.stderr
diff --git a/tests/ui/sanitizer/cfi-invalid-attr-cfi-encoding.rs b/tests/ui/sanitizer/cfi/invalid-attr-encoding.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-invalid-attr-cfi-encoding.rs
rename to tests/ui/sanitizer/cfi/invalid-attr-encoding.rs
diff --git a/tests/ui/sanitizer/cfi-invalid-attr-cfi-encoding.stderr b/tests/ui/sanitizer/cfi/invalid-attr-encoding.stderr
similarity index 79%
rename from tests/ui/sanitizer/cfi-invalid-attr-cfi-encoding.stderr
rename to tests/ui/sanitizer/cfi/invalid-attr-encoding.stderr
index 93ec134241e..1aa6bef17b1 100644
--- a/tests/ui/sanitizer/cfi-invalid-attr-cfi-encoding.stderr
+++ b/tests/ui/sanitizer/cfi/invalid-attr-encoding.stderr
@@ -1,5 +1,5 @@
 error: malformed `cfi_encoding` attribute input
-  --> $DIR/cfi-invalid-attr-cfi-encoding.rs:10:1
+  --> $DIR/invalid-attr-encoding.rs:10:1
    |
 LL | #[cfi_encoding]
    | ^^^^^^^^^^^^^^^ help: must be of the form: `#[cfi_encoding = "encoding"]`
diff --git a/tests/ui/sanitizer/cfi-is-incompatible-with-kcfi.aarch64.stderr b/tests/ui/sanitizer/cfi/is-incompatible-with-kcfi.aarch64.stderr
similarity index 100%
rename from tests/ui/sanitizer/cfi-is-incompatible-with-kcfi.aarch64.stderr
rename to tests/ui/sanitizer/cfi/is-incompatible-with-kcfi.aarch64.stderr
diff --git a/tests/ui/sanitizer/cfi-is-incompatible-with-kcfi.rs b/tests/ui/sanitizer/cfi/is-incompatible-with-kcfi.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-is-incompatible-with-kcfi.rs
rename to tests/ui/sanitizer/cfi/is-incompatible-with-kcfi.rs
diff --git a/tests/ui/sanitizer/cfi-is-incompatible-with-kcfi.x86_64.stderr b/tests/ui/sanitizer/cfi/is-incompatible-with-kcfi.x86_64.stderr
similarity index 100%
rename from tests/ui/sanitizer/cfi-is-incompatible-with-kcfi.x86_64.stderr
rename to tests/ui/sanitizer/cfi/is-incompatible-with-kcfi.x86_64.stderr
diff --git a/tests/ui/sanitizer/cfi-normalize-integers-attr-cfg.rs b/tests/ui/sanitizer/cfi/normalize-integers-attr-cfg.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-normalize-integers-attr-cfg.rs
rename to tests/ui/sanitizer/cfi/normalize-integers-attr-cfg.rs
diff --git a/tests/ui/sanitizer/cfi-normalize-integers-requires-cfi.rs b/tests/ui/sanitizer/cfi/normalize-integers-requires-cfi.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-normalize-integers-requires-cfi.rs
rename to tests/ui/sanitizer/cfi/normalize-integers-requires-cfi.rs
diff --git a/tests/ui/sanitizer/cfi-normalize-integers-requires-cfi.stderr b/tests/ui/sanitizer/cfi/normalize-integers-requires-cfi.stderr
similarity index 100%
rename from tests/ui/sanitizer/cfi-normalize-integers-requires-cfi.stderr
rename to tests/ui/sanitizer/cfi/normalize-integers-requires-cfi.stderr
diff --git a/tests/ui/sanitizer/cfi-requires-lto.rs b/tests/ui/sanitizer/cfi/requires-lto.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-requires-lto.rs
rename to tests/ui/sanitizer/cfi/requires-lto.rs
diff --git a/tests/ui/sanitizer/cfi-requires-lto.stderr b/tests/ui/sanitizer/cfi/requires-lto.stderr
similarity index 100%
rename from tests/ui/sanitizer/cfi-requires-lto.stderr
rename to tests/ui/sanitizer/cfi/requires-lto.stderr
diff --git a/tests/ui/sanitizer/cfi-self-ref.rs b/tests/ui/sanitizer/cfi/self-ref.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-self-ref.rs
rename to tests/ui/sanitizer/cfi/self-ref.rs
diff --git a/tests/ui/sanitizer/cfi-sized-associated-ty.rs b/tests/ui/sanitizer/cfi/sized-associated-ty.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-sized-associated-ty.rs
rename to tests/ui/sanitizer/cfi/sized-associated-ty.rs
diff --git a/tests/ui/sanitizer/cfi-supertraits.rs b/tests/ui/sanitizer/cfi/supertraits.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-supertraits.rs
rename to tests/ui/sanitizer/cfi/supertraits.rs
diff --git a/tests/ui/sanitizer/cfi-virtual-auto.rs b/tests/ui/sanitizer/cfi/virtual-auto.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-virtual-auto.rs
rename to tests/ui/sanitizer/cfi/virtual-auto.rs
diff --git a/tests/ui/sanitizer/cfi-with-rustc-lto-requires-single-codegen-unit.rs b/tests/ui/sanitizer/cfi/with-rustc-lto-requires-single-codegen-unit.rs
similarity index 100%
rename from tests/ui/sanitizer/cfi-with-rustc-lto-requires-single-codegen-unit.rs
rename to tests/ui/sanitizer/cfi/with-rustc-lto-requires-single-codegen-unit.rs
diff --git a/tests/ui/sanitizer/cfi-with-rustc-lto-requires-single-codegen-unit.stderr b/tests/ui/sanitizer/cfi/with-rustc-lto-requires-single-codegen-unit.stderr
similarity index 100%
rename from tests/ui/sanitizer/cfi-with-rustc-lto-requires-single-codegen-unit.stderr
rename to tests/ui/sanitizer/cfi/with-rustc-lto-requires-single-codegen-unit.stderr