revert making internal APIs const fn.

Author: Centril

src/liballoc/collections/binary_heap.rs

@@ -884,7 +884,7 @@ impl<'a, T> Hole<'a, T> {
     }
 
     #[inline]
-    const fn pos(&self) -> usize {
+    fn pos(&self) -> usize {
         self.pos
     }
 

src/liballoc/collections/btree/node.rs

@@ -357,7 +357,7 @@ impl<BorrowType, K, V, Type> NodeRef<BorrowType, K, V, Type> {
 
     /// Returns the height of this node in the whole tree. Zero height denotes the
     /// leaf level.
-    pub const fn height(&self) -> usize {
+    pub fn height(&self) -> usize {
         self.height
     }
 

src/liballoc/collections/linked_list.rs

@@ -135,7 +135,7 @@ impl<T: fmt::Debug> fmt::Debug for IntoIter<T> {
 }
 
 impl<T> Node<T> {
-    const fn new(element: T) -> Self {
+    fn new(element: T) -> Self {
         Node {
             next: None,
             prev: None,

src/liballoc/collections/vec_deque.rs

@@ -1275,7 +1275,7 @@ impl<T> VecDeque<T> {
     }
 
     #[inline]
-    const fn is_contiguous(&self) -> bool {
+    fn is_contiguous(&self) -> bool {
         self.tail <= self.head
     }
 

src/liballoc/raw_vec.rs

@@ -204,7 +204,7 @@ impl<T, A: Alloc> RawVec<T, A> {
     /// Gets a raw pointer to the start of the allocation. Note that this is
     /// Unique::empty() if `cap = 0` or T is zero-sized. In the former case, you must
     /// be careful.
-    pub const fn ptr(&self) -> *mut T {
+    pub fn ptr(&self) -> *mut T {
         self.ptr.as_ptr()
     }
 
@@ -221,7 +221,7 @@ impl<T, A: Alloc> RawVec<T, A> {
     }
 
     /// Returns a shared reference to the allocator backing this RawVec.
-    pub const fn alloc(&self) -> &A {
+    pub fn alloc(&self) -> &A {
         &self.a
     }
 

src/libcore/alloc.rs

@@ -25,7 +25,7 @@ use num::NonZeroUsize;
 #[derive(Debug)]
 pub struct Excess(pub NonNull<u8>, pub usize);
 
-const fn size_align<T>() -> (usize, usize) {
+fn size_align<T>() -> (usize, usize) {
     (mem::size_of::<T>(), mem::align_of::<T>())
 }
 

src/libcore/array.rs

@@ -77,7 +77,7 @@ impl TryFromSliceError {
            issue = "0")]
     #[inline]
     #[doc(hidden)]
-    pub const fn __description(&self) -> &str {
+    pub fn __description(&self) -> &str {
         "could not convert slice to array"
     }
 }

src/libcore/benches/iter.rs

@@ -39,7 +39,7 @@ fn bench_multiple_take(b: &mut Bencher) {
     });
 }
 
-const fn scatter(x: i32) -> i32 { (x * 31) % 127 }
+fn scatter(x: i32) -> i32 { (x * 31) % 127 }
 
 #[bench]
 fn bench_max_by_key(b: &mut Bencher) {

src/libcore/cell.rs

@@ -636,12 +636,12 @@ type BorrowFlag = isize;
 const UNUSED: BorrowFlag = 0;
 
 #[inline(always)]
-const fn is_writing(x: BorrowFlag) -> bool {
+fn is_writing(x: BorrowFlag) -> bool {
     x < UNUSED
 }
 
 #[inline(always)]
-const fn is_reading(x: BorrowFlag) -> bool {
+fn is_reading(x: BorrowFlag) -> bool {
     x > UNUSED
 }
 

src/libcore/fmt/mod.rs

@@ -1703,11 +1703,11 @@ impl<'a> Formatter<'a> {
 
     // FIXME: Decide what public API we want for these two flags.
     // https://github.com/rust-lang/rust/issues/48584
-    const fn debug_lower_hex(&self) -> bool {
+    fn debug_lower_hex(&self) -> bool {
         self.flags & (1 << FlagV1::DebugLowerHex as u32) != 0
     }
 
-    const fn debug_upper_hex(&self) -> bool {
+    fn debug_upper_hex(&self) -> bool {
         self.flags & (1 << FlagV1::DebugUpperHex as u32) != 0
     }