Fix a few stability attributes

These show up in rustdoc so need to be correct.

src/libcollections/btree/map.rs

@@ -1442,6 +1442,7 @@ fn clone(&self) -> Values<'a, K, V> {
     }
 }
 
+#[stable(feature = "btree_range", since = "1.17.0")]
 impl<'a, K, V> Iterator for Range<'a, K, V> {
     type Item = (&'a K, &'a V);
 
@@ -1517,6 +1518,7 @@ unsafe fn next_unchecked(&mut self) -> (&'a K, &'a V) {
     }
 }
 
+#[stable(feature = "btree_range", since = "1.17.0")]
 impl<'a, K, V> DoubleEndedIterator for Range<'a, K, V> {
     fn next_back(&mut self) -> Option<(&'a K, &'a V)> {
         if self.front == self.back {
@@ -1562,6 +1564,7 @@ unsafe fn next_back_unchecked(&mut self) -> (&'a K, &'a V) {
 #[unstable(feature = "fused", issue = "35602")]
 impl<'a, K, V> FusedIterator for Range<'a, K, V> {}
 
+#[stable(feature = "btree_range", since = "1.17.0")]
 impl<'a, K, V> Clone for Range<'a, K, V> {
     fn clone(&self) -> Range<'a, K, V> {
         Range {
@@ -1571,6 +1574,7 @@ fn clone(&self) -> Range<'a, K, V> {
     }
 }
 
+#[stable(feature = "btree_range", since = "1.17.0")]
 impl<'a, K, V> Iterator for RangeMut<'a, K, V> {
     type Item = (&'a K, &'a mut V);
 
@@ -1615,6 +1619,7 @@ unsafe fn next_unchecked(&mut self) -> (&'a K, &'a mut V) {
     }
 }
 
+#[stable(feature = "btree_range", since = "1.17.0")]
 impl<'a, K, V> DoubleEndedIterator for RangeMut<'a, K, V> {
     fn next_back(&mut self) -> Option<(&'a K, &'a mut V)> {
         if self.front == self.back {

src/libcollections/btree/set.rs

@@ -941,11 +941,14 @@ fn len(&self) -> usize { self.iter.len() }
 #[unstable(feature = "fused", issue = "35602")]
 impl<T> FusedIterator for IntoIter<T> {}
 
+#[stable(feature = "btree_range", since = "1.17.0")]
 impl<'a, T> Clone for Range<'a, T> {
     fn clone(&self) -> Range<'a, T> {
         Range { iter: self.iter.clone() }
     }
 }
+
+#[stable(feature = "btree_range", since = "1.17.0")]
 impl<'a, T> Iterator for Range<'a, T> {
     type Item = &'a T;
 
@@ -953,6 +956,8 @@ fn next(&mut self) -> Option<&'a T> {
         self.iter.next().map(|(k, _)| k)
     }
 }
+
+#[stable(feature = "btree_range", since = "1.17.0")]
 impl<'a, T> DoubleEndedIterator for Range<'a, T> {
     fn next_back(&mut self) -> Option<&'a T> {
         self.iter.next_back().map(|(k, _)| k)

src/libcollections/vec_deque.rs

@@ -2272,7 +2272,7 @@ macro_rules! __impl_slice_eq1 {
         __impl_slice_eq1! { $Lhs, $Rhs, Sized }
     };
     ($Lhs: ty, $Rhs: ty, $Bound: ident) => {
-        #[stable(feature = "vec-deque-partial-eq-slice", since = "1.16.0")]
+        #[stable(feature = "vec-deque-partial-eq-slice", since = "1.17.0")]
         impl<'a, 'b, A: $Bound, B> PartialEq<$Rhs> for $Lhs where A: PartialEq<B> {
             fn eq(&self, other: &$Rhs) -> bool {
                 if self.len() != other.len() {

src/libcore/macros.rs

@@ -150,7 +150,7 @@ macro_rules! assert_eq {
 /// assert_ne!(a, b, "we are testing that the values are not equal");
 /// ```
 #[macro_export]
-#[stable(feature = "assert_ne", since = "1.12.0")]
+#[stable(feature = "assert_ne", since = "1.13.0")]
 macro_rules! assert_ne {
     ($left:expr, $right:expr) => ({
         match (&$left, &$right) {
@@ -268,7 +268,7 @@ macro_rules! debug_assert_eq {
 /// debug_assert_ne!(a, b);
 /// ```
 #[macro_export]
-#[stable(feature = "assert_ne", since = "1.12.0")]
+#[stable(feature = "assert_ne", since = "1.13.0")]
 macro_rules! debug_assert_ne {
     ($($arg:tt)*) => (if cfg!(debug_assertions) { assert_ne!($($arg)*); })
 }
@@ -379,7 +379,7 @@ macro_rules! try {
 /// assert_eq!(v, b"s = \"abc 123\"");
 /// ```
 #[macro_export]
-#[stable(feature = "core", since = "1.6.0")]
+#[stable(feature = "rust1", since = "1.0.0")]
 macro_rules! write {
     ($dst:expr, $($arg:tt)*) => ($dst.write_fmt(format_args!($($arg)*)))
 }
@@ -479,7 +479,7 @@ macro_rules! writeln {
 /// }
 /// ```
 #[macro_export]
-#[stable(feature = "core", since = "1.6.0")]
+#[stable(feature = "rust1", since = "1.0.0")]
 macro_rules! unreachable {
     () => ({
         panic!("internal error: entered unreachable code")
@@ -540,7 +540,7 @@ macro_rules! unreachable {
 /// }
 /// ```
 #[macro_export]
-#[stable(feature = "core", since = "1.6.0")]
+#[stable(feature = "rust1", since = "1.0.0")]
 macro_rules! unimplemented {
     () => (panic!("not yet implemented"))
 }

src/libstd/error.rs

@@ -216,7 +216,7 @@ fn from(err: &'a str) -> Box<Error> {
     }
 }
 
-#[stable(feature = "never_error", since = "1.18.0")]
+#[unstable(feature = "never_type_impls", issue = "35121")]
 impl Error for ! {
     fn description(&self) -> &str { *self }
 }