diff --git a/compiler/rustc_mir_transform/src/cross_crate_inline.rs b/compiler/rustc_mir_transform/src/cross_crate_inline.rs
index 42cbece32d8c9..589be81558c2b 100644
--- a/compiler/rustc_mir_transform/src/cross_crate_inline.rs
+++ b/compiler/rustc_mir_transform/src/cross_crate_inline.rs
@@ -50,6 +50,16 @@ fn cross_crate_inlinable(tcx: TyCtxt<'_>, def_id: LocalDefId) -> bool {
         _ => {}
     }
 
+    let sig = tcx.fn_sig(def_id).instantiate_identity();
+    for ty in sig.inputs().skip_binder().iter().chain(std::iter::once(&sig.output().skip_binder()))
+    {
+        // FIXME(f16_f128): in order to avoid crashes building `core`, always inline to skip
+        // codegen if the function is not used.
+        if ty == &tcx.types.f16 || ty == &tcx.types.f128 {
+            return true;
+        }
+    }
+
     // Don't do any inference when incremental compilation is enabled; the additional inlining that
     // inference permits also creates more work for small edits.
     if tcx.sess.opts.incremental.is_some() {
diff --git a/library/core/src/num/f128.rs b/library/core/src/num/f128.rs
index c3862d994986a..3fac1ef099f35 100644
--- a/library/core/src/num/f128.rs
+++ b/library/core/src/num/f128.rs
@@ -1258,9 +1258,8 @@ impl f128 {
             min <= max,
             "min > max, or either was NaN",
             "min > max, or either was NaN. min = {min:?}, max = {max:?}",
-            // FIXME(f16_f128): Passed by-ref to avoid codegen crashes
-            min: &f128 = &min,
-            max: &f128 = &max,
+            min: f128,
+            max: f128,
         );
 
         if self < min {
diff --git a/library/core/src/num/f16.rs b/library/core/src/num/f16.rs
index ed35316cf8f9c..eaac19f22f751 100644
--- a/library/core/src/num/f16.rs
+++ b/library/core/src/num/f16.rs
@@ -1235,9 +1235,8 @@ impl f16 {
             min <= max,
             "min > max, or either was NaN",
             "min > max, or either was NaN. min = {min:?}, max = {max:?}",
-            // FIXME(f16_f128): Passed by-ref to avoid codegen crashes
-            min: &f16 = &min,
-            max: &f16 = &max,
+            min: f16,
+            max: f16,
         );
 
         if self < min {
diff --git a/library/core/src/num/int_macros.rs b/library/core/src/num/int_macros.rs
index 440e75c2113c7..4d24b10209600 100644
--- a/library/core/src/num/int_macros.rs
+++ b/library/core/src/num/int_macros.rs
@@ -1300,7 +1300,7 @@ macro_rules! int_impl {
             }
         }
 
-        /// Unbounded shift left. Computes `self << rhs`, without bounding the value of `rhs`
+        /// Unbounded shift left. Computes `self << rhs`, without bounding the value of `rhs`.
         ///
         /// If `rhs` is larger or equal to the number of bits in `self`,
         /// the entire value is shifted out, and `0` is returned.
@@ -1423,7 +1423,7 @@ macro_rules! int_impl {
             }
         }
 
-        /// Unbounded shift right. Computes `self >> rhs`, without bounding the value of `rhs`
+        /// Unbounded shift right. Computes `self >> rhs`, without bounding the value of `rhs`.
         ///
         /// If `rhs` is larger or equal to the number of bits in `self`,
         /// the entire value is shifted out, which yields `0` for a positive number,
@@ -2389,7 +2389,7 @@ macro_rules! int_impl {
             (res, overflowed ^ (rhs < 0))
         }
 
-        /// Calculates `self` - `rhs`
+        /// Calculates `self` - `rhs`.
         ///
         /// Returns a tuple of the subtraction along with a boolean indicating whether an arithmetic overflow
         /// would occur. If an overflow would have occurred then the wrapped value is returned.
@@ -2470,7 +2470,7 @@ macro_rules! int_impl {
             (c, b != d)
         }
 
-        /// Calculates `self` - `rhs` with an unsigned `rhs`
+        /// Calculates `self` - `rhs` with an unsigned `rhs`.
         ///
         /// Returns a tuple of the subtraction along with a boolean indicating
         /// whether an arithmetic overflow would occur. If an overflow would
diff --git a/library/core/src/num/uint_macros.rs b/library/core/src/num/uint_macros.rs
index 568c5266445da..0a5101884f7d9 100644
--- a/library/core/src/num/uint_macros.rs
+++ b/library/core/src/num/uint_macros.rs
@@ -1517,7 +1517,7 @@ macro_rules! uint_impl {
             }
         }
 
-        /// Unbounded shift left. Computes `self << rhs`, without bounding the value of `rhs`
+        /// Unbounded shift left. Computes `self << rhs`, without bounding the value of `rhs`.
         ///
         /// If `rhs` is larger or equal to the number of bits in `self`,
         /// the entire value is shifted out, and `0` is returned.
@@ -1640,7 +1640,7 @@ macro_rules! uint_impl {
             }
         }
 
-        /// Unbounded shift right. Computes `self >> rhs`, without bounding the value of `rhs`
+        /// Unbounded shift right. Computes `self >> rhs`, without bounding the value of `rhs`.
         ///
         /// If `rhs` is larger or equal to the number of bits in `self`,
         /// the entire value is shifted out, and `0` is returned.
@@ -2299,7 +2299,7 @@ macro_rules! uint_impl {
         ///
         /// # Examples
         ///
-        /// Basic usage
+        /// Basic usage:
         ///
         /// ```
         #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_add(2), (7, false));")]
@@ -2389,7 +2389,7 @@ macro_rules! uint_impl {
             (res, overflowed ^ (rhs < 0))
         }
 
-        /// Calculates `self` - `rhs`
+        /// Calculates `self` - `rhs`.
         ///
         /// Returns a tuple of the subtraction along with a boolean indicating
         /// whether an arithmetic overflow would occur. If an overflow would
@@ -2397,7 +2397,7 @@ macro_rules! uint_impl {
         ///
         /// # Examples
         ///
-        /// Basic usage
+        /// Basic usage:
         ///
         /// ```
         #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_sub(2), (3, false));")]
@@ -2550,7 +2550,7 @@ macro_rules! uint_impl {
         ///
         /// # Examples
         ///
-        /// Basic usage
+        /// Basic usage:
         ///
         /// ```
         #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_div(2), (2, false));")]
@@ -2581,7 +2581,7 @@ macro_rules! uint_impl {
         ///
         /// # Examples
         ///
-        /// Basic usage
+        /// Basic usage:
         ///
         /// ```
         #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_div_euclid(2), (2, false));")]
@@ -2609,7 +2609,7 @@ macro_rules! uint_impl {
         ///
         /// # Examples
         ///
-        /// Basic usage
+        /// Basic usage:
         ///
         /// ```
         #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_rem(2), (1, false));")]
@@ -2640,7 +2640,7 @@ macro_rules! uint_impl {
         ///
         /// # Examples
         ///
-        /// Basic usage
+        /// Basic usage:
         ///
         /// ```
         #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_rem_euclid(2), (1, false));")]
@@ -2664,7 +2664,7 @@ macro_rules! uint_impl {
         ///
         /// # Examples
         ///
-        /// Basic usage
+        /// Basic usage:
         ///
         /// ```
         #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".overflowing_neg(), (0, false));")]
@@ -2689,7 +2689,7 @@ macro_rules! uint_impl {
         ///
         /// # Examples
         ///
-        /// Basic usage
+        /// Basic usage:
         ///
         /// ```
         #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".overflowing_shl(4), (0x10, false));")]
@@ -2715,7 +2715,7 @@ macro_rules! uint_impl {
         ///
         /// # Examples
         ///
-        /// Basic usage
+        /// Basic usage:
         ///
         /// ```
         #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".overflowing_shr(4), (0x1, false));")]
diff --git a/library/core/src/ptr/mod.rs b/library/core/src/ptr/mod.rs
index b98e2b5eac82a..603e904421782 100644
--- a/library/core/src/ptr/mod.rs
+++ b/library/core/src/ptr/mod.rs
@@ -1407,9 +1407,8 @@ pub const unsafe fn read<T>(src: *const T) -> T {
 /// As a result, using `&packed.unaligned as *const FieldType` causes immediate
 /// *undefined behavior* in your program.
 ///
-/// Instead you must use the [`ptr::addr_of!`](addr_of) macro to
-/// create the pointer. You may use that returned pointer together with this
-/// function.
+/// Instead you must use the `&raw const` syntax to create the pointer.
+/// You may use that constructed pointer together with this function.
 ///
 /// An example of what not to do and how this relates to `read_unaligned` is:
 ///
@@ -1427,7 +1426,7 @@ pub const unsafe fn read<T>(src: *const T) -> T {
 ///
 /// // Take the address of a 32-bit integer which is not aligned.
 /// // In contrast to `&packed.unaligned as *const _`, this has no undefined behavior.
-/// let unaligned = std::ptr::addr_of!(packed.unaligned);
+/// let unaligned = &raw const packed.unaligned;
 ///
 /// let v = unsafe { std::ptr::read_unaligned(unaligned) };
 /// assert_eq!(v, 0x01020304);
@@ -1615,9 +1614,8 @@ pub const unsafe fn write<T>(dst: *mut T, src: T) {
 /// As a result, using `&packed.unaligned as *const FieldType` causes immediate
 /// *undefined behavior* in your program.
 ///
-/// Instead, you must use the [`ptr::addr_of_mut!`](addr_of_mut)
-/// macro to create the pointer. You may use that returned pointer together with
-/// this function.
+/// Instead, you must use the `&raw mut` syntax to create the pointer.
+/// You may use that constructed pointer together with this function.
 ///
 /// An example of how to do it and how this relates to `write_unaligned` is:
 ///
@@ -1632,7 +1630,7 @@ pub const unsafe fn write<T>(dst: *mut T, src: T) {
 ///
 /// // Take the address of a 32-bit integer which is not aligned.
 /// // In contrast to `&packed.unaligned as *mut _`, this has no undefined behavior.
-/// let unaligned = std::ptr::addr_of_mut!(packed.unaligned);
+/// let unaligned = &raw mut packed.unaligned;
 ///
 /// unsafe { std::ptr::write_unaligned(unaligned, 42) };
 ///
diff --git a/library/core/src/str/mod.rs b/library/core/src/str/mod.rs
index 0f7c2c999d094..5aecbf303f9f9 100644
--- a/library/core/src/str/mod.rs
+++ b/library/core/src/str/mod.rs
@@ -2400,7 +2400,7 @@ impl str {
     ///
     /// # Examples
     ///
-    /// Basic usage
+    /// Basic usage:
     ///
     /// ```
     /// let four: u32 = "4".parse().unwrap();
diff --git a/library/std/src/fs/tests.rs b/library/std/src/fs/tests.rs
index 05efed6b5dfc6..018e19586418e 100644
--- a/library/std/src/fs/tests.rs
+++ b/library/std/src/fs/tests.rs
@@ -204,6 +204,13 @@ fn file_test_io_seek_and_write() {
 }
 
 #[test]
+#[cfg(any(
+    windows,
+    target_os = "freebsd",
+    target_os = "linux",
+    target_os = "netbsd",
+    target_vendor = "apple",
+))]
 fn file_lock_multiple_shared() {
     let tmpdir = tmpdir();
     let filename = &tmpdir.join("file_lock_multiple_shared_test.txt");
@@ -220,6 +227,13 @@ fn file_lock_multiple_shared() {
 }
 
 #[test]
+#[cfg(any(
+    windows,
+    target_os = "freebsd",
+    target_os = "linux",
+    target_os = "netbsd",
+    target_vendor = "apple",
+))]
 fn file_lock_blocking() {
     let tmpdir = tmpdir();
     let filename = &tmpdir.join("file_lock_blocking_test.txt");
@@ -237,6 +251,13 @@ fn file_lock_blocking() {
 }
 
 #[test]
+#[cfg(any(
+    windows,
+    target_os = "freebsd",
+    target_os = "linux",
+    target_os = "netbsd",
+    target_vendor = "apple",
+))]
 fn file_lock_drop() {
     let tmpdir = tmpdir();
     let filename = &tmpdir.join("file_lock_dup_test.txt");
@@ -251,6 +272,13 @@ fn file_lock_drop() {
 }
 
 #[test]
+#[cfg(any(
+    windows,
+    target_os = "freebsd",
+    target_os = "linux",
+    target_os = "netbsd",
+    target_vendor = "apple",
+))]
 fn file_lock_dup() {
     let tmpdir = tmpdir();
     let filename = &tmpdir.join("file_lock_dup_test.txt");
diff --git a/library/std/src/io/mod.rs b/library/std/src/io/mod.rs
index 71dfd0676c942..21e7077495450 100644
--- a/library/std/src/io/mod.rs
+++ b/library/std/src/io/mod.rs
@@ -1340,6 +1340,25 @@ impl<'a> IoSliceMut<'a> {
             bufs[0].advance(left);
         }
     }
+
+    /// Get the underlying bytes as a mutable slice with the original lifetime.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(io_slice_as_bytes)]
+    /// use std::io::IoSliceMut;
+    ///
+    /// let mut data = *b"abcdef";
+    /// let io_slice = IoSliceMut::new(&mut data);
+    /// io_slice.into_slice()[0] = b'A';
+    ///
+    /// assert_eq!(&data, b"Abcdef");
+    /// ```
+    #[unstable(feature = "io_slice_as_bytes", issue = "132818")]
+    pub const fn into_slice(self) -> &'a mut [u8] {
+        self.0.into_slice()
+    }
 }
 
 #[stable(feature = "iovec", since = "1.36.0")]
@@ -1482,6 +1501,32 @@ impl<'a> IoSlice<'a> {
             bufs[0].advance(left);
         }
     }
+
+    /// Get the underlying bytes as a slice with the original lifetime.
+    ///
+    /// This doesn't borrow from `self`, so is less restrictive than calling
+    /// `.deref()`, which does.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(io_slice_as_bytes)]
+    /// use std::io::IoSlice;
+    ///
+    /// let data = b"abcdef";
+    ///
+    /// let mut io_slice = IoSlice::new(data);
+    /// let tail = &io_slice.as_slice()[3..];
+    ///
+    /// // This works because `tail` doesn't borrow `io_slice`
+    /// io_slice = IoSlice::new(tail);
+    ///
+    /// assert_eq!(io_slice.as_slice(), b"def");
+    /// ```
+    #[unstable(feature = "io_slice_as_bytes", issue = "132818")]
+    pub const fn as_slice(self) -> &'a [u8] {
+        self.0.as_slice()
+    }
 }
 
 #[stable(feature = "iovec", since = "1.36.0")]
diff --git a/library/std/src/io/tests.rs b/library/std/src/io/tests.rs
index 56b71c47dc73c..89e806c08911c 100644
--- a/library/std/src/io/tests.rs
+++ b/library/std/src/io/tests.rs
@@ -531,6 +531,20 @@ fn io_slice_advance_slices_beyond_total_length() {
     assert!(bufs.is_empty());
 }
 
+#[test]
+fn io_slice_as_slice() {
+    let buf = [1; 8];
+    let slice = IoSlice::new(&buf).as_slice();
+    assert_eq!(slice, buf);
+}
+
+#[test]
+fn io_slice_into_slice() {
+    let mut buf = [1; 8];
+    let slice = IoSliceMut::new(&mut buf).into_slice();
+    assert_eq!(slice, [1; 8]);
+}
+
 /// Creates a new writer that reads from at most `n_bufs` and reads
 /// `per_call` bytes (in total) per call to write.
 fn test_writer(n_bufs: usize, per_call: usize) -> TestWriter {
diff --git a/library/std/src/sys/pal/hermit/io.rs b/library/std/src/sys/pal/hermit/io.rs
index aad1eef71e9b0..0424a1ac55a29 100644
--- a/library/std/src/sys/pal/hermit/io.rs
+++ b/library/std/src/sys/pal/hermit/io.rs
@@ -33,7 +33,7 @@ impl<'a> IoSlice<'a> {
     }
 
     #[inline]
-    pub fn as_slice(&self) -> &[u8] {
+    pub const fn as_slice(&self) -> &'a [u8] {
         unsafe { slice::from_raw_parts(self.vec.iov_base as *mut u8, self.vec.iov_len) }
     }
 }
@@ -70,6 +70,11 @@ impl<'a> IoSliceMut<'a> {
         unsafe { slice::from_raw_parts(self.vec.iov_base as *mut u8, self.vec.iov_len) }
     }
 
+    #[inline]
+    pub const fn into_slice(self) -> &'a mut [u8] {
+        unsafe { slice::from_raw_parts_mut(self.vec.iov_base as *mut u8, self.vec.iov_len) }
+    }
+
     #[inline]
     pub fn as_mut_slice(&mut self) -> &mut [u8] {
         unsafe { slice::from_raw_parts_mut(self.vec.iov_base as *mut u8, self.vec.iov_len) }
diff --git a/library/std/src/sys/pal/solid/io.rs b/library/std/src/sys/pal/solid/io.rs
index 4b1f788a492c5..9ef4b7049b690 100644
--- a/library/std/src/sys/pal/solid/io.rs
+++ b/library/std/src/sys/pal/solid/io.rs
@@ -33,7 +33,7 @@ impl<'a> IoSlice<'a> {
     }
 
     #[inline]
-    pub fn as_slice(&self) -> &[u8] {
+    pub const fn as_slice(&self) -> &'a [u8] {
         unsafe { slice::from_raw_parts(self.vec.iov_base as *mut u8, self.vec.iov_len) }
     }
 }
@@ -70,6 +70,11 @@ impl<'a> IoSliceMut<'a> {
         unsafe { slice::from_raw_parts(self.vec.iov_base as *mut u8, self.vec.iov_len) }
     }
 
+    #[inline]
+    pub const fn into_slice(self) -> &'a mut [u8] {
+        unsafe { slice::from_raw_parts_mut(self.vec.iov_base as *mut u8, self.vec.iov_len) }
+    }
+
     #[inline]
     pub fn as_mut_slice(&mut self) -> &mut [u8] {
         unsafe { slice::from_raw_parts_mut(self.vec.iov_base as *mut u8, self.vec.iov_len) }
diff --git a/library/std/src/sys/pal/unix/fs.rs b/library/std/src/sys/pal/unix/fs.rs
index be2363862ee2c..96f99efb21e84 100644
--- a/library/std/src/sys/pal/unix/fs.rs
+++ b/library/std/src/sys/pal/unix/fs.rs
@@ -1254,16 +1254,54 @@ impl File {
         }
     }
 
+    #[cfg(any(
+        target_os = "freebsd",
+        target_os = "linux",
+        target_os = "netbsd",
+        target_vendor = "apple",
+    ))]
     pub fn lock(&self) -> io::Result<()> {
         cvt(unsafe { libc::flock(self.as_raw_fd(), libc::LOCK_EX) })?;
         return Ok(());
     }
 
+    #[cfg(not(any(
+        target_os = "freebsd",
+        target_os = "linux",
+        target_os = "netbsd",
+        target_vendor = "apple",
+    )))]
+    pub fn lock(&self) -> io::Result<()> {
+        Err(io::const_io_error!(io::ErrorKind::Unsupported, "lock() not supported"))
+    }
+
+    #[cfg(any(
+        target_os = "freebsd",
+        target_os = "linux",
+        target_os = "netbsd",
+        target_vendor = "apple",
+    ))]
     pub fn lock_shared(&self) -> io::Result<()> {
         cvt(unsafe { libc::flock(self.as_raw_fd(), libc::LOCK_SH) })?;
         return Ok(());
     }
 
+    #[cfg(not(any(
+        target_os = "freebsd",
+        target_os = "linux",
+        target_os = "netbsd",
+        target_vendor = "apple",
+    )))]
+    pub fn lock_shared(&self) -> io::Result<()> {
+        Err(io::const_io_error!(io::ErrorKind::Unsupported, "lock_shared() not supported"))
+    }
+
+    #[cfg(any(
+        target_os = "freebsd",
+        target_os = "linux",
+        target_os = "netbsd",
+        target_vendor = "apple",
+    ))]
     pub fn try_lock(&self) -> io::Result<bool> {
         let result = cvt(unsafe { libc::flock(self.as_raw_fd(), libc::LOCK_EX | libc::LOCK_NB) });
         if let Err(ref err) = result {
@@ -1275,6 +1313,22 @@ impl File {
         return Ok(true);
     }
 
+    #[cfg(not(any(
+        target_os = "freebsd",
+        target_os = "linux",
+        target_os = "netbsd",
+        target_vendor = "apple",
+    )))]
+    pub fn try_lock(&self) -> io::Result<bool> {
+        Err(io::const_io_error!(io::ErrorKind::Unsupported, "try_lock() not supported"))
+    }
+
+    #[cfg(any(
+        target_os = "freebsd",
+        target_os = "linux",
+        target_os = "netbsd",
+        target_vendor = "apple",
+    ))]
     pub fn try_lock_shared(&self) -> io::Result<bool> {
         let result = cvt(unsafe { libc::flock(self.as_raw_fd(), libc::LOCK_SH | libc::LOCK_NB) });
         if let Err(ref err) = result {
@@ -1286,11 +1340,37 @@ impl File {
         return Ok(true);
     }
 
+    #[cfg(not(any(
+        target_os = "freebsd",
+        target_os = "linux",
+        target_os = "netbsd",
+        target_vendor = "apple",
+    )))]
+    pub fn try_lock_shared(&self) -> io::Result<bool> {
+        Err(io::const_io_error!(io::ErrorKind::Unsupported, "try_lock_shared() not supported"))
+    }
+
+    #[cfg(any(
+        target_os = "freebsd",
+        target_os = "linux",
+        target_os = "netbsd",
+        target_vendor = "apple",
+    ))]
     pub fn unlock(&self) -> io::Result<()> {
         cvt(unsafe { libc::flock(self.as_raw_fd(), libc::LOCK_UN) })?;
         return Ok(());
     }
 
+    #[cfg(not(any(
+        target_os = "freebsd",
+        target_os = "linux",
+        target_os = "netbsd",
+        target_vendor = "apple",
+    )))]
+    pub fn unlock(&self) -> io::Result<()> {
+        Err(io::const_io_error!(io::ErrorKind::Unsupported, "unlock() not supported"))
+    }
+
     pub fn truncate(&self, size: u64) -> io::Result<()> {
         let size: off64_t =
             size.try_into().map_err(|e| io::Error::new(io::ErrorKind::InvalidInput, e))?;
diff --git a/library/std/src/sys/pal/unix/io.rs b/library/std/src/sys/pal/unix/io.rs
index 181c35a971eca..0d5a152dc0dc6 100644
--- a/library/std/src/sys/pal/unix/io.rs
+++ b/library/std/src/sys/pal/unix/io.rs
@@ -33,7 +33,7 @@ impl<'a> IoSlice<'a> {
     }
 
     #[inline]
-    pub fn as_slice(&self) -> &[u8] {
+    pub const fn as_slice(&self) -> &'a [u8] {
         unsafe { slice::from_raw_parts(self.vec.iov_base as *mut u8, self.vec.iov_len) }
     }
 }
@@ -70,6 +70,11 @@ impl<'a> IoSliceMut<'a> {
         unsafe { slice::from_raw_parts(self.vec.iov_base as *mut u8, self.vec.iov_len) }
     }
 
+    #[inline]
+    pub const fn into_slice(self) -> &'a mut [u8] {
+        unsafe { slice::from_raw_parts_mut(self.vec.iov_base as *mut u8, self.vec.iov_len) }
+    }
+
     #[inline]
     pub fn as_mut_slice(&mut self) -> &mut [u8] {
         unsafe { slice::from_raw_parts_mut(self.vec.iov_base as *mut u8, self.vec.iov_len) }
diff --git a/library/std/src/sys/pal/unix/pipe.rs b/library/std/src/sys/pal/unix/pipe.rs
index f0ebc767badad..4a992e32a9184 100644
--- a/library/std/src/sys/pal/unix/pipe.rs
+++ b/library/std/src/sys/pal/unix/pipe.rs
@@ -23,6 +23,7 @@ pub fn anon_pipe() -> io::Result<(AnonPipe, AnonPipe)> {
             target_os = "dragonfly",
             target_os = "freebsd",
             target_os = "hurd",
+            target_os = "illumos",
             target_os = "linux",
             target_os = "netbsd",
             target_os = "openbsd",
diff --git a/library/std/src/sys/pal/unsupported/io.rs b/library/std/src/sys/pal/unsupported/io.rs
index 6372fca74e0d7..604735d32d51a 100644
--- a/library/std/src/sys/pal/unsupported/io.rs
+++ b/library/std/src/sys/pal/unsupported/io.rs
@@ -15,7 +15,7 @@ impl<'a> IoSlice<'a> {
     }
 
     #[inline]
-    pub fn as_slice(&self) -> &[u8] {
+    pub const fn as_slice(&self) -> &'a [u8] {
         self.0
     }
 }
@@ -40,6 +40,11 @@ impl<'a> IoSliceMut<'a> {
         self.0
     }
 
+    #[inline]
+    pub const fn into_slice(self) -> &'a mut [u8] {
+        self.0
+    }
+
     #[inline]
     pub fn as_mut_slice(&mut self) -> &mut [u8] {
         self.0
diff --git a/library/std/src/sys/pal/wasi/io.rs b/library/std/src/sys/pal/wasi/io.rs
index b7c2f03daa048..57f81bc6257cd 100644
--- a/library/std/src/sys/pal/wasi/io.rs
+++ b/library/std/src/sys/pal/wasi/io.rs
@@ -30,7 +30,7 @@ impl<'a> IoSlice<'a> {
     }
 
     #[inline]
-    pub fn as_slice(&self) -> &[u8] {
+    pub const fn as_slice(&self) -> &'a [u8] {
         unsafe { slice::from_raw_parts(self.vec.buf as *const u8, self.vec.buf_len) }
     }
 }
@@ -67,6 +67,11 @@ impl<'a> IoSliceMut<'a> {
         unsafe { slice::from_raw_parts(self.vec.buf as *const u8, self.vec.buf_len) }
     }
 
+    #[inline]
+    pub const fn into_slice(self) -> &'a mut [u8] {
+        unsafe { slice::from_raw_parts_mut(self.vec.buf as *mut u8, self.vec.buf_len) }
+    }
+
     #[inline]
     pub fn as_mut_slice(&mut self) -> &mut [u8] {
         unsafe { slice::from_raw_parts_mut(self.vec.buf as *mut u8, self.vec.buf_len) }
diff --git a/library/std/src/sys/pal/windows/io.rs b/library/std/src/sys/pal/windows/io.rs
index 1e7d02908f63d..f2865d2ffc168 100644
--- a/library/std/src/sys/pal/windows/io.rs
+++ b/library/std/src/sys/pal/windows/io.rs
@@ -36,7 +36,7 @@ impl<'a> IoSlice<'a> {
     }
 
     #[inline]
-    pub fn as_slice(&self) -> &[u8] {
+    pub const fn as_slice(&self) -> &'a [u8] {
         unsafe { slice::from_raw_parts(self.vec.buf, self.vec.len as usize) }
     }
 }
@@ -74,6 +74,11 @@ impl<'a> IoSliceMut<'a> {
         unsafe { slice::from_raw_parts(self.vec.buf, self.vec.len as usize) }
     }
 
+    #[inline]
+    pub const fn into_slice(self) -> &'a mut [u8] {
+        unsafe { slice::from_raw_parts_mut(self.vec.buf, self.vec.len as usize) }
+    }
+
     #[inline]
     pub fn as_mut_slice(&mut self) -> &mut [u8] {
         unsafe { slice::from_raw_parts_mut(self.vec.buf, self.vec.len as usize) }
diff --git a/tests/codegen/float/f16-f128-inline.rs b/tests/codegen/float/f16-f128-inline.rs
new file mode 100644
index 0000000000000..aa2c38c209e86
--- /dev/null
+++ b/tests/codegen/float/f16-f128-inline.rs
@@ -0,0 +1,29 @@
+//@ revisions: default nopt
+//@[nopt] compile-flags: -Copt-level=0 -Zcross-crate-inline-threshold=never -Zmir-opt-level=0 -Cno-prepopulate-passes
+
+// Ensure that functions using `f16` and `f128` are always inlined to avoid crashes
+// when the backend does not support these types.
+
+#![crate_type = "lib"]
+#![feature(f128)]
+#![feature(f16)]
+
+pub fn f16_arg(_a: f16) {
+    // CHECK-NOT: f16_arg
+    todo!()
+}
+
+pub fn f16_ret() -> f16 {
+    // CHECK-NOT: f16_ret
+    todo!()
+}
+
+pub fn f128_arg(_a: f128) {
+    // CHECK-NOT: f128_arg
+    todo!()
+}
+
+pub fn f128_ret() -> f128 {
+    // CHECK-NOT: f128_ret
+    todo!()
+}
diff --git a/tests/run-make/simd-ffi/simd.rs b/tests/run-make/simd-ffi/simd.rs
index b72078faafa26..9ea8eb8cf8831 100644
--- a/tests/run-make/simd-ffi/simd.rs
+++ b/tests/run-make/simd-ffi/simd.rs
@@ -25,7 +25,7 @@ pub struct i32x4([i32; 4]);
 
 extern "C" {
     // _mm_sll_epi32
-    #[cfg(any(target_arch = "x86", target_arch = "x86-64"))]
+    #[cfg(all(any(target_arch = "x86", target_arch = "x86-64"), target_feature = "sse2"))]
     #[link_name = "llvm.x86.sse2.psll.d"]
     fn integer(a: i32x4, b: i32x4) -> i32x4;
 
@@ -38,15 +38,13 @@ extern "C" {
     #[link_name = "llvm.aarch64.neon.maxs.v4i32"]
     fn integer(a: i32x4, b: i32x4) -> i32x4;
 
-    // just some substitute foreign symbol, not an LLVM intrinsic; so
-    // we still get type checking, but not as detailed as (ab)using
-    // LLVM.
+    // Use a generic LLVM intrinsic to do type checking on other platforms
     #[cfg(not(any(
-        target_arch = "x86",
-        target_arch = "x86-64",
+        all(any(target_arch = "x86", target_arch = "x86-64"), target_feature = "sse2"),
         target_arch = "arm",
         target_arch = "aarch64"
     )))]
+    #[link_name = "llvm.smax.v4i32"]
     fn integer(a: i32x4, b: i32x4) -> i32x4;
 }
 
diff --git a/tests/ui/extern-flag/auxiliary/panic_handler.rs b/tests/ui/extern-flag/auxiliary/panic_handler.rs
index 5ca32fa992b05..9140ceed22914 100644
--- a/tests/ui/extern-flag/auxiliary/panic_handler.rs
+++ b/tests/ui/extern-flag/auxiliary/panic_handler.rs
@@ -1,14 +1,10 @@
-#![feature(lang_items)]
+#![feature(lang_items, panic_unwind)]
 #![no_std]
 
-// Since `rustc` generally passes `-nodefaultlibs` to the linker,
-// Rust programs link necessary system libraries via `#[link()]`
-// attributes in the `libc` crate. `libc` is a dependency of `std`,
-// but as we are `#![no_std]`, we need to include it manually.
-// Except on windows-msvc.
-#![feature(rustc_private)]
-#[cfg(not(all(windows, target_env = "msvc")))]
-extern crate libc;
+// Since the `unwind` crate is a dependency of the `std` crate, and we have
+// `#![no_std]`, the unwinder is not included in the link command by default.
+// We need to include crate `unwind` manually.
+extern crate unwind;
 
 #[panic_handler]
 pub fn begin_panic_handler(_info: &core::panic::PanicInfo<'_>) -> ! {