reduce list to functions callable in const ctx.

26 files changed, 55 insertions, 55 deletions

diff --git a/src/liballoc/collections/btree/map.rs b/src/liballoc/collections/btree/map.rs
index 8a721a50b46..24c8fd3a969 100644
--- a/src/liballoc/collections/btree/map.rs
+++ b/src/liballoc/collections/btree/map.rs
@@ -2074,7 +2074,7 @@ impl<K, V> BTreeMap<K, V> {
     /// assert_eq!(a.len(), 1);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn len(&self) -> usize {
+    pub fn len(&self) -> usize {
         self.length
     }
 
@@ -2093,7 +2093,7 @@ impl<K, V> BTreeMap<K, V> {
     /// assert!(!a.is_empty());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn is_empty(&self) -> bool {
+    pub fn is_empty(&self) -> bool {
         self.len() == 0
     }
 }
diff --git a/src/liballoc/collections/btree/set.rs b/src/liballoc/collections/btree/set.rs
index 6a0ecfd3f58..af9a7074e4a 100644
--- a/src/liballoc/collections/btree/set.rs
+++ b/src/liballoc/collections/btree/set.rs
@@ -730,7 +730,7 @@ impl<T> BTreeSet<T> {
     /// assert_eq!(v.len(), 1);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn len(&self) -> usize {
+    pub fn len(&self) -> usize {
         self.map.len()
     }
 
@@ -747,7 +747,7 @@ impl<T> BTreeSet<T> {
     /// assert!(!v.is_empty());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn is_empty(&self) -> bool {
+    pub fn is_empty(&self) -> bool {
         self.len() == 0
     }
 }
diff --git a/src/liballoc/collections/vec_deque.rs b/src/liballoc/collections/vec_deque.rs
index b139b440fe1..e0ae7561d45 100644
--- a/src/liballoc/collections/vec_deque.rs
+++ b/src/liballoc/collections/vec_deque.rs
@@ -933,7 +933,7 @@ impl<T> VecDeque<T> {
     /// assert!(!v.is_empty());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn is_empty(&self) -> bool {
+    pub fn is_empty(&self) -> bool {
         self.tail == self.head
     }
 
diff --git a/src/liballoc/string.rs b/src/liballoc/string.rs
index 8f379c4cfb4..5c776292f53 100644
--- a/src/liballoc/string.rs
+++ b/src/liballoc/string.rs
@@ -1374,7 +1374,7 @@ impl String {
     /// ```
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn len(&self) -> usize {
+    pub fn len(&self) -> usize {
         self.vec.len()
     }
 
@@ -1395,7 +1395,7 @@ impl String {
     /// ```
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn is_empty(&self) -> bool {
+    pub fn is_empty(&self) -> bool {
         self.len() == 0
     }
 
@@ -1662,7 +1662,7 @@ impl FromUtf8Error {
     /// assert_eq!(1, error.valid_up_to());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn utf8_error(&self) -> Utf8Error {
+    pub fn utf8_error(&self) -> Utf8Error {
         self.error
     }
 }
diff --git a/src/liballoc/vec.rs b/src/liballoc/vec.rs
index 78e9da2084d..f7a0bbdceaf 100644
--- a/src/liballoc/vec.rs
+++ b/src/liballoc/vec.rs
@@ -1165,7 +1165,7 @@ impl<T> Vec<T> {
     /// ```
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn len(&self) -> usize {
+    pub fn len(&self) -> usize {
         self.len
     }
 
@@ -1181,7 +1181,7 @@ impl<T> Vec<T> {
     /// assert!(!v.is_empty());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn is_empty(&self) -> bool {
+    pub fn is_empty(&self) -> bool {
         self.len() == 0
     }
 
diff --git a/src/libcore/alloc.rs b/src/libcore/alloc.rs
index 8b9f7f2c816..045fabca268 100644
--- a/src/libcore/alloc.rs
+++ b/src/libcore/alloc.rs
@@ -116,7 +116,7 @@ impl Layout {
     /// The minimum size in bytes for a memory block of this layout.
     #[stable(feature = "alloc_layout", since = "1.28.0")]
     #[inline]
-    pub const fn size(&self) -> usize { self.size_ }
+    pub fn size(&self) -> usize { self.size_ }
 
     /// The minimum byte alignment for a memory block of this layout.
     #[stable(feature = "alloc_layout", since = "1.28.0")]
diff --git a/src/libcore/char/decode.rs b/src/libcore/char/decode.rs
index bcd1e92c6d8..cc52f048b89 100644
--- a/src/libcore/char/decode.rs
+++ b/src/libcore/char/decode.rs
@@ -130,7 +130,7 @@ impl<I: Iterator<Item = u16>> Iterator for DecodeUtf16<I> {
 impl DecodeUtf16Error {
     /// Returns the unpaired surrogate which caused this error.
     #[stable(feature = "decode_utf16", since = "1.9.0")]
-    pub const fn unpaired_surrogate(&self) -> u16 {
+    pub fn unpaired_surrogate(&self) -> u16 {
         self.code
     }
 }
diff --git a/src/libcore/fmt/mod.rs b/src/libcore/fmt/mod.rs
index 56576f8334b..4fde4e79ee2 100644
--- a/src/libcore/fmt/mod.rs
+++ b/src/libcore/fmt/mod.rs
@@ -341,7 +341,7 @@ impl<'a> Arguments<'a> {
     #[doc(hidden)] #[inline]
     #[unstable(feature = "fmt_internals", reason = "internal to format_args!",
                issue = "0")]
-    pub const fn new_v1(pieces: &'a [&'a str],
+    pub fn new_v1(pieces: &'a [&'a str],
                   args: &'a [ArgumentV1<'a>]) -> Arguments<'a> {
         Arguments {
             pieces,
@@ -359,7 +359,7 @@ impl<'a> Arguments<'a> {
     #[doc(hidden)] #[inline]
     #[unstable(feature = "fmt_internals", reason = "internal to format_args!",
                issue = "0")]
-    pub const fn new_v1_formatted(pieces: &'a [&'a str],
+    pub fn new_v1_formatted(pieces: &'a [&'a str],
                             args: &'a [ArgumentV1<'a>],
                             fmt: &'a [rt::v1::Argument]) -> Arguments<'a> {
         Arguments {
@@ -1492,7 +1492,7 @@ impl<'a> Formatter<'a> {
     /// assert_eq!(&format!("{:t>6}", Foo), "tttttt");
     /// ```
     #[stable(feature = "fmt_flags", since = "1.5.0")]
-    pub const fn fill(&self) -> char { self.fill }
+    pub fn fill(&self) -> char { self.fill }
 
     /// Flag indicating what form of alignment was requested.
     ///
@@ -1562,7 +1562,7 @@ impl<'a> Formatter<'a> {
     /// assert_eq!(&format!("{}", Foo(23)), "Foo(23)");
     /// ```
     #[stable(feature = "fmt_flags", since = "1.5.0")]
-    pub const fn width(&self) -> Option<usize> { self.width }
+    pub fn width(&self) -> Option<usize> { self.width }
 
     /// Optionally specified precision for numeric types.
     ///
@@ -1589,7 +1589,7 @@ impl<'a> Formatter<'a> {
     /// assert_eq!(&format!("{}", Foo(23.2)), "Foo(23.20)");
     /// ```
     #[stable(feature = "fmt_flags", since = "1.5.0")]
-    pub const fn precision(&self) -> Option<usize> { self.precision }
+    pub fn precision(&self) -> Option<usize> { self.precision }
 
     /// Determines if the `+` flag was specified.
     ///
@@ -1617,7 +1617,7 @@ impl<'a> Formatter<'a> {
     /// assert_eq!(&format!("{}", Foo(23)), "Foo(23)");
     /// ```
     #[stable(feature = "fmt_flags", since = "1.5.0")]
-    pub const fn sign_plus(&self) -> bool {
+    pub fn sign_plus(&self) -> bool {
         self.flags & (1 << FlagV1::SignPlus as u32) != 0
     }
 
@@ -1645,7 +1645,7 @@ impl<'a> Formatter<'a> {
     /// assert_eq!(&format!("{}", Foo(23)), "Foo(23)");
     /// ```
     #[stable(feature = "fmt_flags", since = "1.5.0")]
-    pub const fn sign_minus(&self) -> bool {
+    pub fn sign_minus(&self) -> bool {
         self.flags & (1 << FlagV1::SignMinus as u32) != 0
     }
 
@@ -1672,7 +1672,7 @@ impl<'a> Formatter<'a> {
     /// assert_eq!(&format!("{}", Foo(23)), "23");
     /// ```
     #[stable(feature = "fmt_flags", since = "1.5.0")]
-    pub const fn alternate(&self) -> bool {
+    pub fn alternate(&self) -> bool {
         self.flags & (1 << FlagV1::Alternate as u32) != 0
     }
 
@@ -1697,7 +1697,7 @@ impl<'a> Formatter<'a> {
     /// assert_eq!(&format!("{:04}", Foo(23)), "23");
     /// ```
     #[stable(feature = "fmt_flags", since = "1.5.0")]
-    pub const fn sign_aware_zero_pad(&self) -> bool {
+    pub fn sign_aware_zero_pad(&self) -> bool {
         self.flags & (1 << FlagV1::SignAwareZeroPad as u32) != 0
     }
 
diff --git a/src/libcore/panic.rs b/src/libcore/panic.rs
index af9d1596938..f0efeb59e8d 100644
--- a/src/libcore/panic.rs
+++ b/src/libcore/panic.rs
@@ -55,7 +55,7 @@ impl<'a> PanicInfo<'a> {
                 issue = "0")]
     #[doc(hidden)]
     #[inline]
-    pub const fn internal_constructor(message: Option<&'a fmt::Arguments<'a>>,
+    pub fn internal_constructor(message: Option<&'a fmt::Arguments<'a>>,
                                 location: Location<'a>)
                                 -> Self {
         struct NoPayload;
@@ -96,7 +96,7 @@ impl<'a> PanicInfo<'a> {
     ///
     /// [`fmt::write`]: ../fmt/fn.write.html
     #[unstable(feature = "panic_info_message", issue = "44489")]
-    pub const fn message(&self) -> Option<&fmt::Arguments> {
+    pub fn message(&self) -> Option<&fmt::Arguments> {
         self.message
     }
 
@@ -125,7 +125,7 @@ impl<'a> PanicInfo<'a> {
     /// panic!("Normal panic");
     /// ```
     #[stable(feature = "panic_hooks", since = "1.10.0")]
-    pub const fn location(&self) -> Option<&Location> {
+    pub fn location(&self) -> Option<&Location> {
         // NOTE: If this is changed to sometimes return None,
         // deal with that case in std::panicking::default_hook and std::panicking::begin_panic_fmt.
         Some(&self.location)
@@ -186,7 +186,7 @@ impl<'a> Location<'a> {
                           and related macros",
                 issue = "0")]
     #[doc(hidden)]
-    pub const fn internal_constructor(file: &'a str, line: u32, col: u32) -> Self {
+    pub fn internal_constructor(file: &'a str, line: u32, col: u32) -> Self {
         Location { file, line, col }
     }
 
@@ -208,7 +208,7 @@ impl<'a> Location<'a> {
     /// panic!("Normal panic");
     /// ```
     #[stable(feature = "panic_hooks", since = "1.10.0")]
-    pub const fn file(&self) -> &str {
+    pub fn file(&self) -> &str {
         self.file
     }
 
@@ -230,7 +230,7 @@ impl<'a> Location<'a> {
     /// panic!("Normal panic");
     /// ```
     #[stable(feature = "panic_hooks", since = "1.10.0")]
-    pub const fn line(&self) -> u32 {
+    pub fn line(&self) -> u32 {
         self.line
     }
 
@@ -252,7 +252,7 @@ impl<'a> Location<'a> {
     /// panic!("Normal panic");
     /// ```
     #[stable(feature = "panic_col", since = "1.25.0")]
-    pub const fn column(&self) -> u32 {
+    pub fn column(&self) -> u32 {
         self.col
     }
 }
diff --git a/src/libcore/pin.rs b/src/libcore/pin.rs
index 63a433a8b23..68de82d2945 100644
--- a/src/libcore/pin.rs
+++ b/src/libcore/pin.rs
@@ -207,7 +207,7 @@ impl<'a, T: ?Sized> Pin<&'a T> {
     /// with the same lifetime as the original `Pin`.
     #[unstable(feature = "pin", issue = "49150")]
     #[inline(always)]
-    pub const fn get_ref(this: Pin<&'a T>) -> &'a T {
+    pub fn get_ref(this: Pin<&'a T>) -> &'a T {
         this.pointer
     }
 }
@@ -216,7 +216,7 @@ impl<'a, T: ?Sized> Pin<&'a mut T> {
     /// Convert this `Pin<&mut T>` into a `Pin<&T>` with the same lifetime.
     #[unstable(feature = "pin", issue = "49150")]
     #[inline(always)]
-    pub const fn into_ref(this: Pin<&'a mut T>) -> Pin<&'a T> {
+    pub fn into_ref(this: Pin<&'a mut T>) -> Pin<&'a T> {
         Pin { pointer: this.pointer }
     }
 
diff --git a/src/libcore/slice/mod.rs b/src/libcore/slice/mod.rs
index f8dee537062..dae425da789 100644
--- a/src/libcore/slice/mod.rs
+++ b/src/libcore/slice/mod.rs
@@ -4021,7 +4021,7 @@ impl<'a, T> ChunksExact<'a, T> {
     /// returned by the iterator. The returned slice has at most `chunk_size-1`
     /// elements.
     #[stable(feature = "chunks_exact", since = "1.31.0")]
-    pub const fn remainder(&self) -> &'a [T] {
+    pub fn remainder(&self) -> &'a [T] {
         self.rem
     }
 }
@@ -4517,7 +4517,7 @@ impl<'a, T> RChunksExact<'a, T> {
     /// returned by the iterator. The returned slice has at most `chunk_size-1`
     /// elements.
     #[stable(feature = "rchunks", since = "1.31.0")]
-    pub const fn remainder(&self) -> &'a [T] {
+    pub fn remainder(&self) -> &'a [T] {
         self.rem
     }
 }
diff --git a/src/libcore/str/lossy.rs b/src/libcore/str/lossy.rs
index 950552fc6b1..186d6adbc91 100644
--- a/src/libcore/str/lossy.rs
+++ b/src/libcore/str/lossy.rs
@@ -29,7 +29,7 @@ impl Utf8Lossy {
         unsafe { mem::transmute(bytes) }
     }
 
-    pub const fn chunks(&self) -> Utf8LossyChunksIter {
+    pub fn chunks(&self) -> Utf8LossyChunksIter {
         Utf8LossyChunksIter { source: &self.bytes }
     }
 }
diff --git a/src/libcore/str/mod.rs b/src/libcore/str/mod.rs
index d73e5db727c..f5bfe804899 100644
--- a/src/libcore/str/mod.rs
+++ b/src/libcore/str/mod.rs
@@ -231,7 +231,7 @@ impl Utf8Error {
     /// assert_eq!(1, error.valid_up_to());
     /// ```
     #[stable(feature = "utf8_error", since = "1.5.0")]
-    pub const fn valid_up_to(&self) -> usize { self.valid_up_to }
+    pub fn valid_up_to(&self) -> usize { self.valid_up_to }
 
     /// Provide more information about the failure:
     ///
diff --git a/src/libcore/task/wake.rs b/src/libcore/task/wake.rs
index 1db3a290e04..c9fb22e0080 100644
--- a/src/libcore/task/wake.rs
+++ b/src/libcore/task/wake.rs
@@ -141,7 +141,7 @@ impl LocalWaker {
     /// `Waker` is nearly identical to `LocalWaker`, but is threadsafe
     /// (implements `Send` and `Sync`).
     #[inline]
-    pub const fn as_waker(&self) -> &Waker {
+    pub fn as_waker(&self) -> &Waker {
         &self.0
     }
 
diff --git a/src/libstd/collections/hash/map.rs b/src/libstd/collections/hash/map.rs
index b95449d11ea..c18f200872d 100644
--- a/src/libstd/collections/hash/map.rs
+++ b/src/libstd/collections/hash/map.rs
@@ -3013,7 +3013,7 @@ impl<'a, K: 'a, V: 'a> VacantEntry<'a, K, V> {
     /// assert_eq!(map.entry("poneyland").key(), &"poneyland");
     /// ```
     #[stable(feature = "map_entry_keys", since = "1.10.0")]
-    pub const fn key(&self) -> &K {
+    pub fn key(&self) -> &K {
         &self.key
     }
 
diff --git a/src/libstd/ffi/c_str.rs b/src/libstd/ffi/c_str.rs
index feff65bff3f..e2dc02e40bf 100644
--- a/src/libstd/ffi/c_str.rs
+++ b/src/libstd/ffi/c_str.rs
@@ -833,7 +833,7 @@ impl NulError {
     /// assert_eq!(nul_error.nul_position(), 7);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn nul_position(&self) -> usize { self.0 }
+    pub fn nul_position(&self) -> usize { self.0 }
 
     /// Consumes this error, returning the underlying vector of bytes which
     /// generated the error in the first place.
@@ -909,7 +909,7 @@ impl IntoStringError {
 
     /// Access the underlying UTF-8 error that was the cause of this error.
     #[stable(feature = "cstring_into", since = "1.7.0")]
-    pub const fn utf8_error(&self) -> Utf8Error {
+    pub fn utf8_error(&self) -> Utf8Error {
         self.error
     }
 }
diff --git a/src/libstd/io/buffered.rs b/src/libstd/io/buffered.rs
index bde9c57c57c..e26e6d391f8 100644
--- a/src/libstd/io/buffered.rs
+++ b/src/libstd/io/buffered.rs
@@ -633,7 +633,7 @@ impl<W> IntoInnerError<W> {
     /// };
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn error(&self) -> &Error { &self.1 }
+    pub fn error(&self) -> &Error { &self.1 }
 
     /// Returns the buffered writer instance which generated the error.
     ///
diff --git a/src/libstd/io/mod.rs b/src/libstd/io/mod.rs
index 4c3117260fe..c07d4a2e755 100644
--- a/src/libstd/io/mod.rs
+++ b/src/libstd/io/mod.rs
@@ -1653,7 +1653,7 @@ impl<T, U> Chain<T, U> {
     /// }
     /// ```
     #[stable(feature = "more_io_inner_methods", since = "1.20.0")]
-    pub const fn get_ref(&self) -> (&T, &U) {
+    pub fn get_ref(&self) -> (&T, &U) {
         (&self.first, &self.second)
     }
 
@@ -1780,7 +1780,7 @@ impl<T> Take<T> {
     /// }
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn limit(&self) -> u64 { self.limit }
+    pub fn limit(&self) -> u64 { self.limit }
 
     /// Sets the number of bytes that can be read before this instance will
     /// return EOF. This is the same as constructing a new `Take` instance, so
@@ -1856,7 +1856,7 @@ impl<T> Take<T> {
     /// }
     /// ```
     #[stable(feature = "more_io_inner_methods", since = "1.20.0")]
-    pub const fn get_ref(&self) -> &T {
+    pub fn get_ref(&self) -> &T {
         &self.inner
     }
 
diff --git a/src/libstd/net/addr.rs b/src/libstd/net/addr.rs
index fc2e8104782..ff35325ab4f 100644
--- a/src/libstd/net/addr.rs
+++ b/src/libstd/net/addr.rs
@@ -475,7 +475,7 @@ impl SocketAddrV6 {
     /// assert_eq!(socket.flowinfo(), 10);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn flowinfo(&self) -> u32 {
+    pub fn flowinfo(&self) -> u32 {
         self.inner.sin6_flowinfo
     }
 
@@ -515,7 +515,7 @@ impl SocketAddrV6 {
     /// assert_eq!(socket.scope_id(), 78);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn scope_id(&self) -> u32 {
+    pub fn scope_id(&self) -> u32 {
         self.inner.sin6_scope_id
     }
 
diff --git a/src/libstd/net/ip.rs b/src/libstd/net/ip.rs
index c5106c9abb9..2517c45696a 100644
--- a/src/libstd/net/ip.rs
+++ b/src/libstd/net/ip.rs
@@ -402,7 +402,7 @@ impl Ipv4Addr {
     /// assert_eq!(addr.octets(), [127, 0, 0, 1]);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub  fn octets(&self) -> [u8; 4] {
+    pub fn octets(&self) -> [u8; 4] {
         let bits = u32::from_be(self.inner.s_addr);
         [(bits >> 24) as u8, (bits >> 16) as u8, (bits >> 8) as u8, bits as u8]
     }
diff --git a/src/libstd/path.rs b/src/libstd/path.rs
index 71f39ff85e7..a153456370c 100644
--- a/src/libstd/path.rs
+++ b/src/libstd/path.rs
@@ -439,7 +439,7 @@ impl<'a> PrefixComponent<'a> {
     ///
     /// [`Prefix`]: enum.Prefix.html
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn kind(&self) -> Prefix<'a> {
+    pub fn kind(&self) -> Prefix<'a> {
         self.parsed
     }
 
@@ -447,7 +447,7 @@ impl<'a> PrefixComponent<'a> {
     ///
     /// [`OsStr`]: ../../std/ffi/struct.OsStr.html
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn as_os_str(&self) -> &'a OsStr {
+    pub fn as_os_str(&self) -> &'a OsStr {
         self.raw
     }
 }
@@ -1918,7 +1918,7 @@ impl Path {
     /// [`None`]: ../../std/option/enum.Option.html#variant.None
     /// [`parent`]: struct.Path.html#method.parent
     #[stable(feature = "path_ancestors", since = "1.28.0")]
-    pub const fn ancestors(&self) -> Ancestors {
+    pub fn ancestors(&self) -> Ancestors {
         Ancestors {
             next: Some(&self),
         }
@@ -2267,7 +2267,7 @@ impl Path {
     /// println!("{}", path.display());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn display(&self) -> Display {
+    pub fn display(&self) -> Display {
         Display { path: self }
     }
 
diff --git a/src/libstd/sync/condvar.rs b/src/libstd/sync/condvar.rs
index 1c6cc9cb361..3014283da5b 100644
--- a/src/libstd/sync/condvar.rs
+++ b/src/libstd/sync/condvar.rs
@@ -72,7 +72,7 @@ impl WaitTimeoutResult {
     /// }
     /// ```
     #[stable(feature = "wait_timeout", since = "1.5.0")]
-    pub const fn timed_out(&self) -> bool {
+    pub fn timed_out(&self) -> bool {
         self.0
     }
 }
diff --git a/src/libstd/sync/mpsc/mod.rs b/src/libstd/sync/mpsc/mod.rs
index 2a2e5c030b3..b726168c7c6 100644
--- a/src/libstd/sync/mpsc/mod.rs
+++ b/src/libstd/sync/mpsc/mod.rs
@@ -1469,7 +1469,7 @@ impl<T> Receiver<T> {
     /// assert_eq!(iter.next(), None);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn iter(&self) -> Iter<T> {
+    pub fn iter(&self) -> Iter<T> {
         Iter { rx: self }
     }
 
@@ -1512,7 +1512,7 @@ impl<T> Receiver<T> {
     /// assert_eq!(iter.next(), None);
     /// ```
     #[stable(feature = "receiver_try_iter", since = "1.15.0")]
-    pub const fn try_iter(&self) -> TryIter<T> {
+    pub fn try_iter(&self) -> TryIter<T> {
         TryIter { rx: self }
     }
 
diff --git a/src/libstd/sync/once.rs b/src/libstd/sync/once.rs
index 4dd37ec3878..cf9698cb2a9 100644
--- a/src/libstd/sync/once.rs
+++ b/src/libstd/sync/once.rs
@@ -517,7 +517,7 @@ impl OnceState {
     ///     assert!(!state.poisoned());
     /// });
     #[unstable(feature = "once_poison", issue = "33577")]
-    pub const fn poisoned(&self) -> bool {
+    pub fn poisoned(&self) -> bool {
         self.poisoned
     }
 }
diff --git a/src/libstd/thread/mod.rs b/src/libstd/thread/mod.rs
index 3a3d2450014..e9a97f7c747 100644
--- a/src/libstd/thread/mod.rs
+++ b/src/libstd/thread/mod.rs
@@ -1391,7 +1391,7 @@ impl<T> JoinHandle<T> {
     /// println!("thread id: {:?}", thread.id());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub const fn thread(&self) -> &Thread {
+    pub fn thread(&self) -> &Thread {
         &self.0.thread
     }
 
diff --git a/src/libstd/time.rs b/src/libstd/time.rs
index a9344941f42..90ab3491599 100644
--- a/src/libstd/time.rs
+++ b/src/libstd/time.rs
@@ -449,7 +449,7 @@ impl SystemTimeError {
     /// }
     /// ```
     #[stable(feature = "time2", since = "1.8.0")]
-    pub const fn duration(&self) -> Duration {
+    pub fn duration(&self) -> Duration {
         self.0
     }
 }