From c7cffc5f4ef1def337ca2a294c3ca855ee703419 Mon Sep 17 00:00:00 2001
From: Alexis Beingessner <a.beingessner@gmail.com>
Date: Thu, 4 May 2017 14:48:58 -0400
Subject: Deprecate heap::EMPTY in favour of Unique::empty or otherwise.

---
 src/liballoc/boxed.rs   |  2 +-
 src/liballoc/heap.rs    |  6 ++++--
 src/liballoc/raw_vec.rs | 26 ++++++++++++--------------
 3 files changed, 17 insertions(+), 17 deletions(-)

(limited to 'src/liballoc')

diff --git a/src/liballoc/boxed.rs b/src/liballoc/boxed.rs
index b03e3bb7a4b..fc6929f896e 100644
--- a/src/liballoc/boxed.rs
+++ b/src/liballoc/boxed.rs
@@ -156,7 +156,7 @@ fn make_place<T>() -> IntermediateBox<T> {
     let align = mem::align_of::<T>();
 
     let p = if size == 0 {
-        heap::EMPTY as *mut u8
+        mem::align_of::<T>() as *mut u8
     } else {
         let p = unsafe { heap::allocate(size, align) };
         if p.is_null() {
diff --git a/src/liballoc/heap.rs b/src/liballoc/heap.rs
index 056af13016c..5ff21c86483 100644
--- a/src/liballoc/heap.rs
+++ b/src/liballoc/heap.rs
@@ -138,7 +138,9 @@ pub fn usable_size(size: usize, align: usize) -> usize {
 ///
 /// This preserves the non-null invariant for types like `Box<T>`. The address
 /// may overlap with non-zero-size memory allocations.
-pub const EMPTY: *mut () = 0x1 as *mut ();
+#[rustc_deprecated(since = "1.19", reason = "Use Unique/Shared::empty() instead")]
+#[unstable(feature = "heap_api", issue = "27700")]
+pub const EMPTY: *mut () = 1 as *mut ();
 
 /// The allocator for unique pointers.
 // This function must not unwind. If it does, MIR trans will fail.
@@ -147,7 +149,7 @@ pub const EMPTY: *mut () = 0x1 as *mut ();
 #[inline]
 unsafe fn exchange_malloc(size: usize, align: usize) -> *mut u8 {
     if size == 0 {
-        EMPTY as *mut u8
+        align as *mut u8
     } else {
         let ptr = allocate(size, align);
         if ptr.is_null() {
diff --git a/src/liballoc/raw_vec.rs b/src/liballoc/raw_vec.rs
index 1f6f5ba17ed..7edf07944ec 100644
--- a/src/liballoc/raw_vec.rs
+++ b/src/liballoc/raw_vec.rs
@@ -22,13 +22,13 @@ use core::cmp;
 /// involved. This type is excellent for building your own data structures like Vec and VecDeque.
 /// In particular:
 ///
-/// * Produces heap::EMPTY on zero-sized types
-/// * Produces heap::EMPTY on zero-length allocations
+/// * Produces Unique::empty() on zero-sized types
+/// * Produces Unique::empty() on zero-length allocations
 /// * Catches all overflows in capacity computations (promotes them to "capacity overflow" panics)
 /// * Guards against 32-bit systems allocating more than isize::MAX bytes
 /// * Guards against overflowing your length
 /// * Aborts on OOM
-/// * Avoids freeing heap::EMPTY
+/// * Avoids freeing Unique::empty()
 /// * Contains a ptr::Unique and thus endows the user with all related benefits
 ///
 /// This type does not in anyway inspect the memory that it manages. When dropped it *will*
@@ -55,15 +55,13 @@ impl<T> RawVec<T> {
     /// it makes a RawVec with capacity `usize::MAX`. Useful for implementing
     /// delayed allocation.
     pub fn new() -> Self {
-        unsafe {
-            // !0 is usize::MAX. This branch should be stripped at compile time.
-            let cap = if mem::size_of::<T>() == 0 { !0 } else { 0 };
+        // !0 is usize::MAX. This branch should be stripped at compile time.
+        let cap = if mem::size_of::<T>() == 0 { !0 } else { 0 };
 
-            // heap::EMPTY doubles as "unallocated" and "zero-sized allocation"
-            RawVec {
-                ptr: Unique::new(heap::EMPTY as *mut T),
-                cap: cap,
-            }
+        // Unique::empty() doubles as "unallocated" and "zero-sized allocation"
+        RawVec {
+            ptr: Unique::empty(),
+            cap: cap,
         }
     }
 
@@ -101,7 +99,7 @@ impl<T> RawVec<T> {
 
             // handles ZSTs and `cap = 0` alike
             let ptr = if alloc_size == 0 {
-                heap::EMPTY as *mut u8
+                mem::align_of::<T>() as *mut u8
             } else {
                 let align = mem::align_of::<T>();
                 let ptr = if zeroed {
@@ -148,10 +146,10 @@ impl<T> RawVec<T> {
 
 impl<T> RawVec<T> {
     /// Gets a raw pointer to the start of the allocation. Note that this is
-    /// heap::EMPTY if `cap = 0` or T is zero-sized. In the former case, you must
+    /// Unique::empty() if `cap = 0` or T is zero-sized. In the former case, you must
     /// be careful.
     pub fn ptr(&self) -> *mut T {
-        self.ptr.ptr()
+        self.ptr.as_ptr()
     }
 
     /// Gets the capacity of the allocation.
-- 
cgit 1.4.1-3-g733a5