From 79449986b707c18df92622a53d83eddd6872d8ee Mon Sep 17 00:00:00 2001
From: Ivan Tham <pickfire@riseup.net>
Date: Sun, 31 May 2020 17:16:47 +0800
Subject: [PATCH 1/2] Rearrange impl blocks with Deref as first

The other blocks depends on Deref to make it easier for readers when
reimplementing or reading the implementations.
---
 src/liballoc/vec.rs | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/src/liballoc/vec.rs b/src/liballoc/vec.rs
index 42fb1f8c737b3..6409c66b08140 100644
--- a/src/liballoc/vec.rs
+++ b/src/liballoc/vec.rs
@@ -1900,6 +1900,22 @@ unsafe impl<T: ?Sized> IsZero for Option<Box<T>> {
 // Common trait implementations for Vec
 ////////////////////////////////////////////////////////////////////////////////
 
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<T> ops::Deref for Vec<T> {
+    type Target = [T];
+
+    fn deref(&self) -> &[T] {
+        unsafe { slice::from_raw_parts(self.as_ptr(), self.len) }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<T> ops::DerefMut for Vec<T> {
+    fn deref_mut(&mut self) -> &mut [T] {
+        unsafe { slice::from_raw_parts_mut(self.as_mut_ptr(), self.len) }
+    }
+}
+
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T: Clone> Clone for Vec<T> {
     #[cfg(not(test))]
@@ -1955,22 +1971,6 @@ impl<T, I: SliceIndex<[T]>> IndexMut<I> for Vec<T> {
     }
 }
 
-#[stable(feature = "rust1", since = "1.0.0")]
-impl<T> ops::Deref for Vec<T> {
-    type Target = [T];
-
-    fn deref(&self) -> &[T] {
-        unsafe { slice::from_raw_parts(self.as_ptr(), self.len) }
-    }
-}
-
-#[stable(feature = "rust1", since = "1.0.0")]
-impl<T> ops::DerefMut for Vec<T> {
-    fn deref_mut(&mut self) -> &mut [T] {
-        unsafe { slice::from_raw_parts_mut(self.as_mut_ptr(), self.len) }
-    }
-}
-
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T> FromIterator<T> for Vec<T> {
     #[inline]

From 71404633e843e0e5a533c677a764c8cb7f2a55fb Mon Sep 17 00:00:00 2001
From: Ivan Tham <pickfire@riseup.net>
Date: Sun, 31 May 2020 17:19:06 +0800
Subject: [PATCH 2/2] Merge raw_vec into_box with previous impl<T, Global>

There are two separate `impl<T, Global>` which no special reason, it would be
better to merge both of them.
---
 src/liballoc/raw_vec.rs | 50 ++++++++++++++++++++---------------------
 1 file changed, 24 insertions(+), 26 deletions(-)

diff --git a/src/liballoc/raw_vec.rs b/src/liballoc/raw_vec.rs
index 56e284a12fa83..5b365f0387a9b 100644
--- a/src/liballoc/raw_vec.rs
+++ b/src/liballoc/raw_vec.rs
@@ -118,6 +118,30 @@ impl<T> RawVec<T, Global> {
             RawVec::from_raw_parts(slice.as_mut_ptr(), slice.len())
         }
     }
+
+    /// Converts the entire buffer into `Box<[MaybeUninit<T>]>` with the specified `len`.
+    ///
+    /// Note that this will correctly reconstitute any `cap` changes
+    /// that may have been performed. (See description of type for details.)
+    ///
+    /// # Safety
+    ///
+    /// * `len` must be greater than or equal to the most recently requested capacity, and
+    /// * `len` must be less than or equal to `self.capacity()`.
+    ///
+    /// Note, that the requested capacity and `self.capacity()` could differ, as
+    /// an allocator could overallocate and return a greater memory block than requested.
+    pub unsafe fn into_box(self, len: usize) -> Box<[MaybeUninit<T>]> {
+        // Sanity-check one half of the safety requirement (we cannot check the other half).
+        debug_assert!(
+            len <= self.capacity(),
+            "`len` must be smaller than or equal to `self.capacity()`"
+        );
+
+        let me = ManuallyDrop::new(self);
+        let slice = slice::from_raw_parts_mut(me.ptr() as *mut MaybeUninit<T>, len);
+        Box::from_raw(slice)
+    }
 }
 
 impl<T, A: AllocRef> RawVec<T, A> {
@@ -520,32 +544,6 @@ where
     Ok(memory)
 }
 
-impl<T> RawVec<T, Global> {
-    /// Converts the entire buffer into `Box<[MaybeUninit<T>]>` with the specified `len`.
-    ///
-    /// Note that this will correctly reconstitute any `cap` changes
-    /// that may have been performed. (See description of type for details.)
-    ///
-    /// # Safety
-    ///
-    /// * `len` must be greater than or equal to the most recently requested capacity, and
-    /// * `len` must be less than or equal to `self.capacity()`.
-    ///
-    /// Note, that the requested capacity and `self.capacity()` could differ, as
-    /// an allocator could overallocate and return a greater memory block than requested.
-    pub unsafe fn into_box(self, len: usize) -> Box<[MaybeUninit<T>]> {
-        // Sanity-check one half of the safety requirement (we cannot check the other half).
-        debug_assert!(
-            len <= self.capacity(),
-            "`len` must be smaller than or equal to `self.capacity()`"
-        );
-
-        let me = ManuallyDrop::new(self);
-        let slice = slice::from_raw_parts_mut(me.ptr() as *mut MaybeUninit<T>, len);
-        Box::from_raw(slice)
-    }
-}
-
 unsafe impl<#[may_dangle] T, A: AllocRef> Drop for RawVec<T, A> {
     /// Frees the memory owned by the `RawVec` *without* trying to drop its contents.
     fn drop(&mut self) {