libcore: Make it unsafe to create NonZero and impl Deref.

1 files changed, 20 insertions, 26 deletions

diff --git a/src/libcollections/vec.rs b/src/libcollections/vec.rs
index 0739cef3353..6f618657280 100644
--- a/src/libcollections/vec.rs
+++ b/src/libcollections/vec.rs
@@ -176,7 +176,7 @@ impl<T> Vec<T> {
         // non-null value which is fine since we never call deallocate on the ptr
         // if cap is 0. The reason for this is because the pointer of a slice
         // being NULL would break the null pointer optimization for enums.
-        Vec { ptr: NonZero(EMPTY as *mut T), len: 0, cap: 0 }
+        Vec { ptr: unsafe { NonZero::new(EMPTY as *mut T) }, len: 0, cap: 0 }
     }
 
     /// Constructs a new, empty `Vec<T>` with the specified capacity.
@@ -209,7 +209,7 @@ impl<T> Vec<T> {
     #[stable]
     pub fn with_capacity(capacity: uint) -> Vec<T> {
         if mem::size_of::<T>() == 0 {
-            Vec { ptr: NonZero(EMPTY as *mut T), len: 0, cap: uint::MAX }
+            Vec { ptr: unsafe { NonZero::new(EMPTY as *mut T) }, len: 0, cap: uint::MAX }
         } else if capacity == 0 {
             Vec::new()
         } else {
@@ -217,7 +217,7 @@ impl<T> Vec<T> {
                                .expect("capacity overflow");
             let ptr = unsafe { allocate(size, mem::min_align_of::<T>()) };
             if ptr.is_null() { ::alloc::oom() }
-            Vec { ptr: NonZero(ptr as *mut T), len: 0, cap: capacity }
+            Vec { ptr: unsafe { NonZero::new(ptr as *mut T) }, len: 0, cap: capacity }
         }
     }
 
@@ -284,7 +284,7 @@ impl<T> Vec<T> {
     #[unstable = "needs finalization"]
     pub unsafe fn from_raw_parts(ptr: *mut T, length: uint,
                                  capacity: uint) -> Vec<T> {
-        Vec { ptr: NonZero(ptr), len: length, cap: capacity }
+        Vec { ptr: NonZero::new(ptr), len: length, cap: capacity }
     }
 
     /// Creates a vector by copying the elements from a raw pointer.
@@ -792,11 +792,10 @@ impl<T> Vec<T> {
     pub fn shrink_to_fit(&mut self) {
         if mem::size_of::<T>() == 0 { return }
 
-        let NonZero(ptr) = self.ptr;
         if self.len == 0 {
             if self.cap != 0 {
                 unsafe {
-                    dealloc(ptr, self.cap)
+                    dealloc(*self.ptr, self.cap)
                 }
                 self.cap = 0;
             }
@@ -804,12 +803,12 @@ impl<T> Vec<T> {
             unsafe {
                 // Overflow check is unnecessary as the vector is already at
                 // least this large.
-                let ptr = reallocate(ptr as *mut u8,
+                let ptr = reallocate(*self.ptr as *mut u8,
                                      self.cap * mem::size_of::<T>(),
                                      self.len * mem::size_of::<T>(),
                                      mem::min_align_of::<T>()) as *mut T;
                 if ptr.is_null() { ::alloc::oom() }
-                self.ptr = NonZero(ptr);
+                self.ptr = NonZero::new(ptr);
             }
             self.cap = self.len;
         }
@@ -867,10 +866,9 @@ impl<T> Vec<T> {
     #[inline]
     #[stable]
     pub fn as_mut_slice<'a>(&'a mut self) -> &'a mut [T] {
-        let NonZero(ptr) = self.ptr;
         unsafe {
             mem::transmute(RawSlice {
-                data: ptr as *const T,
+                data: *self.ptr as *const T,
                 len: self.len,
             })
         }
@@ -893,7 +891,7 @@ impl<T> Vec<T> {
     #[unstable = "matches collection reform specification, waiting for dust to settle"]
     pub fn into_iter(self) -> IntoIter<T> {
         unsafe {
-            let NonZero(ptr) = self.ptr;
+            let ptr = *self.ptr;
             let cap = self.cap;
             let begin = ptr as *const T;
             let end = if mem::size_of::<T>() == 0 {
@@ -1113,16 +1111,15 @@ impl<T> Vec<T> {
             let size = max(old_size, 2 * mem::size_of::<T>()) * 2;
             if old_size > size { panic!("capacity overflow") }
             unsafe {
-                let NonZero(ptr) = self.ptr;
-                let ptr = alloc_or_realloc(ptr, old_size, size);
+                let ptr = alloc_or_realloc(*self.ptr, old_size, size);
                 if ptr.is_null() { ::alloc::oom() }
-                self.ptr = NonZero(ptr);
+                self.ptr = NonZero::new(ptr);
             }
             self.cap = max(self.cap, 2) * 2;
         }
 
         unsafe {
-            let NonZero(end) = self.ptr.offset(self.len as int);
+            let end = *self.ptr.offset(self.len as int);
             ptr::write(&mut *end, value);
             self.len += 1;
         }
@@ -1167,11 +1164,11 @@ impl<T> Vec<T> {
     #[unstable = "matches collection reform specification, waiting for dust to settle"]
     pub fn drain<'a>(&'a mut self) -> Drain<'a, T> {
         unsafe {
-            let begin = self.ptr.0 as *const T;
+            let begin = *self.ptr as *const T;
             let end = if mem::size_of::<T>() == 0 {
-                (self.ptr.0 as uint + self.len()) as *const T
+                (*self.ptr as uint + self.len()) as *const T
             } else {
-                self.ptr.0.offset(self.len() as int) as *const T
+                (*self.ptr).offset(self.len() as int) as *const T
             };
             self.set_len(0);
             Drain {
@@ -1236,10 +1233,9 @@ impl<T> Vec<T> {
             let size = capacity.checked_mul(mem::size_of::<T>())
                                .expect("capacity overflow");
             unsafe {
-                let NonZero(ptr) = self.ptr;
-                let ptr = alloc_or_realloc(ptr, self.cap * mem::size_of::<T>(), size);
+                let ptr = alloc_or_realloc(*self.ptr, self.cap * mem::size_of::<T>(), size);
                 if ptr.is_null() { ::alloc::oom() }
-                self.ptr = NonZero(ptr);
+                self.ptr = NonZero::new(ptr);
             }
             self.cap = capacity;
         }
@@ -1360,10 +1356,9 @@ impl<T> AsSlice<T> for Vec<T> {
     #[inline]
     #[stable]
     fn as_slice<'a>(&'a self) -> &'a [T] {
-        let NonZero(ptr) = self.ptr;
         unsafe {
             mem::transmute(RawSlice {
-                data: ptr as *const T,
+                data: *self.ptr as *const T,
                 len: self.len
             })
         }
@@ -1388,8 +1383,7 @@ impl<T> Drop for Vec<T> {
                 for x in self.iter() {
                     ptr::read(x);
                 }
-                let NonZero(ptr) = self.ptr;
-                dealloc(ptr, self.cap)
+                dealloc(*self.ptr, self.cap)
             }
         }
     }
@@ -1427,7 +1421,7 @@ impl<T> IntoIter<T> {
             for _x in self { }
             let IntoIter { allocation, cap, ptr: _ptr, end: _end } = self;
             mem::forget(self);
-            Vec { ptr: NonZero(allocation), cap: cap, len: 0 }
+            Vec { ptr: NonZero::new(allocation), cap: cap, len: 0 }
         }
     }