Auto merge of #77102 - Dylan-DPC:rollup-2jfrg3u, r=Dylan-DPC

Rollup of 9 pull requests

Successful merges:

 - #76898 (Record `tcx.def_span` instead of `item.span` in crate metadata)
 - #76939 (emit errors during AbstractConst building)
 - #76965 (Add cfg(target_has_atomic_equal_alignment) and use it for Atomic::from_mut.)
 - #76993 (Changing the alloc() to accept &self instead of &mut self)
 - #76994 (fix small typo in docs and comments)
 - #77017 (Add missing examples on Vec iter types)
 - #77042 (Improve documentation for ToSocketAddrs)
 - #77047 (Miri: more informative deallocation error messages)
 - #77055 (Add #[track_caller] to more panicking Cell functions)

Failed merges:

r? `@ghost`

library/std/src/alloc.rs

@@ -133,7 +133,7 @@ pub struct System;
 
 impl System {
     #[inline]
-    fn alloc_impl(&mut self, layout: Layout, zeroed: bool) -> Result<NonNull<[u8]>, AllocErr> {
+    fn alloc_impl(&self, layout: Layout, zeroed: bool) -> Result<NonNull<[u8]>, AllocErr> {
         match layout.size() {
             0 => Ok(NonNull::slice_from_raw_parts(layout.dangling(), 0)),
             // SAFETY: `layout` is non-zero in size,
@@ -152,7 +152,7 @@ impl System {
     // SAFETY: Same as `AllocRef::grow`
     #[inline]
     unsafe fn grow_impl(
-        &mut self,
+        &self,
         ptr: NonNull<u8>,
         old_layout: Layout,
         new_layout: Layout,
@@ -190,7 +190,7 @@ impl System {
             old_size => unsafe {
                 let new_ptr = self.alloc_impl(new_layout, zeroed)?;
                 ptr::copy_nonoverlapping(ptr.as_ptr(), new_ptr.as_mut_ptr(), old_size);
-                self.dealloc(ptr, old_layout);
+                AllocRef::dealloc(&self, ptr, old_layout);
                 Ok(new_ptr)
             },
         }
@@ -202,17 +202,17 @@ impl System {
 #[unstable(feature = "allocator_api", issue = "32838")]
 unsafe impl AllocRef for System {
     #[inline]
-    fn alloc(&mut self, layout: Layout) -> Result<NonNull<[u8]>, AllocErr> {
+    fn alloc(&self, layout: Layout) -> Result<NonNull<[u8]>, AllocErr> {
         self.alloc_impl(layout, false)
     }
 
     #[inline]
-    fn alloc_zeroed(&mut self, layout: Layout) -> Result<NonNull<[u8]>, AllocErr> {
+    fn alloc_zeroed(&self, layout: Layout) -> Result<NonNull<[u8]>, AllocErr> {
         self.alloc_impl(layout, true)
     }
 
     #[inline]
-    unsafe fn dealloc(&mut self, ptr: NonNull<u8>, layout: Layout) {
+    unsafe fn dealloc(&self, ptr: NonNull<u8>, layout: Layout) {
         if layout.size() != 0 {
             // SAFETY: `layout` is non-zero in size,
             // other conditions must be upheld by the caller
@@ -222,7 +222,7 @@ unsafe impl AllocRef for System {
 
     #[inline]
     unsafe fn grow(
-        &mut self,
+        &self,
         ptr: NonNull<u8>,
         old_layout: Layout,
         new_layout: Layout,
@@ -233,7 +233,7 @@ unsafe impl AllocRef for System {
 
     #[inline]
     unsafe fn grow_zeroed(
-        &mut self,
+        &self,
         ptr: NonNull<u8>,
         old_layout: Layout,
         new_layout: Layout,
@@ -244,7 +244,7 @@ unsafe impl AllocRef for System {
 
     #[inline]
     unsafe fn shrink(
-        &mut self,
+        &self,
         ptr: NonNull<u8>,
         old_layout: Layout,
         new_layout: Layout,
@@ -257,7 +257,7 @@ unsafe impl AllocRef for System {
         match new_layout.size() {
             // SAFETY: conditions must be upheld by the caller
             0 => unsafe {
-                self.dealloc(ptr, old_layout);
+                AllocRef::dealloc(&self, ptr, old_layout);
                 Ok(NonNull::slice_from_raw_parts(new_layout.dangling(), 0))
             },
 
@@ -277,9 +277,9 @@ unsafe impl AllocRef for System {
             // `new_ptr`. Thus, the call to `copy_nonoverlapping` is safe. The safety contract
             // for `dealloc` must be upheld by the caller.
             new_size => unsafe {
-                let new_ptr = self.alloc(new_layout)?;
+                let new_ptr = AllocRef::alloc(&self, new_layout)?;
                 ptr::copy_nonoverlapping(ptr.as_ptr(), new_ptr.as_mut_ptr(), new_size);
-                self.dealloc(ptr, old_layout);
+                AllocRef::dealloc(&self, ptr, old_layout);
                 Ok(new_ptr)
             },
         }

library/std/src/net/addr.rs

@@ -745,9 +745,9 @@ impl hash::Hash for SocketAddrV6 {
 ///    `(`[`Ipv4Addr`]`, `[`u16`]`)`, `(`[`Ipv6Addr`]`, `[`u16`]`)`:
 ///    [`to_socket_addrs`] constructs a [`SocketAddr`] trivially.
 ///
-///  * `(`[`&str`]`, `[`u16`]`)`: the string should be either a string representation
+///  * `(`[`&str`]`, `[`u16`]`)`: [`&str`] should be either a string representation
 ///    of an [`IpAddr`] address as expected by [`FromStr`] implementation or a host
-///    name.
+///    name. [`u16`] is the port number.
 ///
 ///  * [`&str`]: the string should be either a string representation of a
 ///    [`SocketAddr`] as expected by its [`FromStr`] implementation or a string like