Auto merge of rust-lang#127757 - workingjubilee:rollup-4dbks5r, r=workingjubilee

Rollup of 3 pull requests

Successful merges:

 - rust-lang#127712 (Windows: Remove some unnecessary type aliases)
 - rust-lang#127744 (std: `#![deny(unsafe_op_in_unsafe_fn)]` in platform-independent code)
 - rust-lang#127750 (Make os/windows and pal/windows default to `#![deny(unsafe_op_in_unsafe_fn)]`)

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

Author: bors

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

@@ -1018,7 +1018,7 @@ where
         K: Borrow<Q>,
         Q: Hash + Eq,
     {
-        self.base.get_many_unchecked_mut(ks)
+        unsafe { self.base.get_many_unchecked_mut(ks) }
     }
 
     /// Returns `true` if the map contains a value for the specified key.

library/std/src/env.rs

@@ -366,11 +366,8 @@ impl Error for VarError {
 #[rustc_deprecated_safe_2024]
 #[stable(feature = "env", since = "1.0.0")]
 pub unsafe fn set_var<K: AsRef<OsStr>, V: AsRef<OsStr>>(key: K, value: V) {
-    _set_var(key.as_ref(), value.as_ref())
-}
-
-unsafe fn _set_var(key: &OsStr, value: &OsStr) {
-    os_imp::setenv(key, value).unwrap_or_else(|e| {
+    let (key, value) = (key.as_ref(), value.as_ref());
+    unsafe { os_imp::setenv(key, value) }.unwrap_or_else(|e| {
         panic!("failed to set environment variable `{key:?}` to `{value:?}`: {e}")
     })
 }
@@ -433,11 +430,8 @@ unsafe fn _set_var(key: &OsStr, value: &OsStr) {
 #[rustc_deprecated_safe_2024]
 #[stable(feature = "env", since = "1.0.0")]
 pub unsafe fn remove_var<K: AsRef<OsStr>>(key: K) {
-    _remove_var(key.as_ref())
-}
-
-unsafe fn _remove_var(key: &OsStr) {
-    os_imp::unsetenv(key)
+    let key = key.as_ref();
+    unsafe { os_imp::unsetenv(key) }
         .unwrap_or_else(|e| panic!("failed to remove environment variable `{key:?}`: {e}"))
 }
 

library/std/src/ffi/os_str.rs

@@ -184,7 +184,7 @@ impl OsString {
     #[inline]
     #[stable(feature = "os_str_bytes", since = "1.74.0")]
     pub unsafe fn from_encoded_bytes_unchecked(bytes: Vec<u8>) -> Self {
-        OsString { inner: Buf::from_encoded_bytes_unchecked(bytes) }
+        OsString { inner: unsafe { Buf::from_encoded_bytes_unchecked(bytes) } }
     }
 
     /// Converts to an [`OsStr`] slice.
@@ -813,7 +813,7 @@ impl OsStr {
     #[inline]
     #[stable(feature = "os_str_bytes", since = "1.74.0")]
     pub unsafe fn from_encoded_bytes_unchecked(bytes: &[u8]) -> &Self {
-        Self::from_inner(Slice::from_encoded_bytes_unchecked(bytes))
+        Self::from_inner(unsafe { Slice::from_encoded_bytes_unchecked(bytes) })
     }
 
     #[inline]

library/std/src/io/buffered/bufwriter.rs

@@ -433,9 +433,11 @@ impl<W: ?Sized + Write> BufWriter<W> {
         let old_len = self.buf.len();
         let buf_len = buf.len();
         let src = buf.as_ptr();
-        let dst = self.buf.as_mut_ptr().add(old_len);
-        ptr::copy_nonoverlapping(src, dst, buf_len);
-        self.buf.set_len(old_len + buf_len);
+        unsafe {
+            let dst = self.buf.as_mut_ptr().add(old_len);
+            ptr::copy_nonoverlapping(src, dst, buf_len);
+            self.buf.set_len(old_len + buf_len);
+        }
     }
 
     #[inline]

library/std/src/io/cursor.rs

@@ -482,7 +482,7 @@ where
     A: Allocator,
 {
     debug_assert!(vec.capacity() >= pos + buf.len());
-    vec.as_mut_ptr().add(pos).copy_from(buf.as_ptr(), buf.len());
+    unsafe { vec.as_mut_ptr().add(pos).copy_from(buf.as_ptr(), buf.len()) };
     pos + buf.len()
 }
 

library/std/src/io/error/repr_bitpacked.rs

@@ -267,11 +267,14 @@ where
                 // Using this rather than unwrap meaningfully improves the code
                 // for callers which only care about one variant (usually
                 // `Custom`)
-                core::hint::unreachable_unchecked();
+                unsafe { core::hint::unreachable_unchecked() };
             });
             ErrorData::Simple(kind)
         }
-        TAG_SIMPLE_MESSAGE => ErrorData::SimpleMessage(&*ptr.cast::<SimpleMessage>().as_ptr()),
+        TAG_SIMPLE_MESSAGE => {
+            // SAFETY: per tag
+            unsafe { ErrorData::SimpleMessage(&*ptr.cast::<SimpleMessage>().as_ptr()) }
+        }
         TAG_CUSTOM => {
             // It would be correct for us to use `ptr::byte_sub` here (see the
             // comment above the `wrapping_add` call in `new_custom` for why),

library/std/src/io/mod.rs

@@ -382,11 +382,11 @@ pub(crate) unsafe fn append_to_string<F>(buf: &mut String, f: F) -> Result<usize
 where
     F: FnOnce(&mut Vec<u8>) -> Result<usize>,
 {
-    let mut g = Guard { len: buf.len(), buf: buf.as_mut_vec() };
+    let mut g = Guard { len: buf.len(), buf: unsafe { buf.as_mut_vec() } };
     let ret = f(g.buf);
 
     // SAFETY: the caller promises to only append data to `buf`
-    let appended = g.buf.get_unchecked(g.len..);
+    let appended = unsafe { g.buf.get_unchecked(g.len..) };
     if str::from_utf8(appended).is_err() {
         ret.and_then(|_| Err(Error::INVALID_UTF8))
     } else {

library/std/src/lib.rs

@@ -252,6 +252,7 @@
 #![allow(internal_features)]
 #![deny(rustc::existing_doc_keyword)]
 #![deny(fuzzy_provenance_casts)]
+#![deny(unsafe_op_in_unsafe_fn)]
 #![allow(rustdoc::redundant_explicit_links)]
 // Ensure that std can be linked against panic_abort despite compiled with `-C panic=unwind`
 #![deny(ffi_unwind_calls)]
@@ -664,7 +665,7 @@ pub mod alloc;
 mod panicking;
 
 #[path = "../../backtrace/src/lib.rs"]
-#[allow(dead_code, unused_attributes, fuzzy_provenance_casts)]
+#[allow(dead_code, unused_attributes, fuzzy_provenance_casts, unsafe_op_in_unsafe_fn)]
 mod backtrace_rs;
 
 // Re-export macros defined in core.

library/std/src/os/mod.rs

@@ -2,6 +2,7 @@
 
 #![stable(feature = "os", since = "1.0.0")]
 #![allow(missing_docs, nonstandard_style, missing_debug_implementations)]
+#![allow(unsafe_op_in_unsafe_fn)]
 
 pub mod raw;
 

library/std/src/os/windows/io/raw.rs

@@ -159,10 +159,12 @@ fn stdio_handle(raw: RawHandle) -> RawHandle {
 impl FromRawHandle for fs::File {
     #[inline]
     unsafe fn from_raw_handle(handle: RawHandle) -> fs::File {
-        let handle = handle as sys::c::HANDLE;
-        fs::File::from_inner(sys::fs::File::from_inner(FromInner::from_inner(
-            OwnedHandle::from_raw_handle(handle),
-        )))
+        unsafe {
+            let handle = handle as sys::c::HANDLE;
+            fs::File::from_inner(sys::fs::File::from_inner(FromInner::from_inner(
+                OwnedHandle::from_raw_handle(handle),
+            )))
+        }
     }
 }
 
@@ -260,24 +262,30 @@ impl AsRawSocket for net::UdpSocket {
 impl FromRawSocket for net::TcpStream {
     #[inline]
     unsafe fn from_raw_socket(sock: RawSocket) -> net::TcpStream {
-        let sock = sys::net::Socket::from_inner(OwnedSocket::from_raw_socket(sock));
-        net::TcpStream::from_inner(sys_common::net::TcpStream::from_inner(sock))
+        unsafe {
+            let sock = sys::net::Socket::from_inner(OwnedSocket::from_raw_socket(sock));
+            net::TcpStream::from_inner(sys_common::net::TcpStream::from_inner(sock))
+        }
     }
 }
 #[stable(feature = "from_raw_os", since = "1.1.0")]
 impl FromRawSocket for net::TcpListener {
     #[inline]
     unsafe fn from_raw_socket(sock: RawSocket) -> net::TcpListener {
-        let sock = sys::net::Socket::from_inner(OwnedSocket::from_raw_socket(sock));
-        net::TcpListener::from_inner(sys_common::net::TcpListener::from_inner(sock))
+        unsafe {
+            let sock = sys::net::Socket::from_inner(OwnedSocket::from_raw_socket(sock));
+            net::TcpListener::from_inner(sys_common::net::TcpListener::from_inner(sock))
+        }
     }
 }
 #[stable(feature = "from_raw_os", since = "1.1.0")]
 impl FromRawSocket for net::UdpSocket {
     #[inline]
     unsafe fn from_raw_socket(sock: RawSocket) -> net::UdpSocket {
-        let sock = sys::net::Socket::from_inner(OwnedSocket::from_raw_socket(sock));
-        net::UdpSocket::from_inner(sys_common::net::UdpSocket::from_inner(sock))
+        unsafe {
+            let sock = sys::net::Socket::from_inner(OwnedSocket::from_raw_socket(sock));
+            net::UdpSocket::from_inner(sys_common::net::UdpSocket::from_inner(sock))
+        }
     }
 }