diff --git a/library/alloc/src/alloc.rs b/library/alloc/src/alloc.rs
index 3427c83a18f2a..edbbe3603a713 100644
--- a/library/alloc/src/alloc.rs
+++ b/library/alloc/src/alloc.rs
@@ -358,7 +358,7 @@ extern "Rust" {
 /// [`set_alloc_error_hook`]: ../../std/alloc/fn.set_alloc_error_hook.html
 /// [`take_alloc_error_hook`]: ../../std/alloc/fn.take_alloc_error_hook.html
 #[stable(feature = "global_alloc", since = "1.28.0")]
-#[cfg(not(any(test, bootstrap)))]
+#[cfg(not(test))]
 #[rustc_allocator_nounwind]
 pub fn handle_alloc_error(layout: Layout) -> ! {
     unsafe {
@@ -370,22 +370,7 @@ pub fn handle_alloc_error(layout: Layout) -> ! {
 #[cfg(test)]
 pub use std::alloc::handle_alloc_error;
 
-// In stage0 (bootstrap) `__rust_alloc_error_handler`,
-// might not be generated yet, because an old compiler is used,
-// so use the old direct call.
-#[cfg(all(bootstrap, not(test)))]
-#[stable(feature = "global_alloc", since = "1.28.0")]
-#[doc(hidden)]
-#[rustc_allocator_nounwind]
-pub fn handle_alloc_error(layout: Layout) -> ! {
-    extern "Rust" {
-        #[lang = "oom"]
-        fn oom_impl(layout: Layout) -> !;
-    }
-    unsafe { oom_impl(layout) }
-}
-
-#[cfg(not(any(target_os = "hermit", test, bootstrap)))]
+#[cfg(not(any(target_os = "hermit", test)))]
 #[doc(hidden)]
 #[allow(unused_attributes)]
 #[unstable(feature = "alloc_internals", issue = "none")]
diff --git a/library/alloc/src/lib.rs b/library/alloc/src/lib.rs
index f21fc8854d05e..dc5db49ee9891 100644
--- a/library/alloc/src/lib.rs
+++ b/library/alloc/src/lib.rs
@@ -72,7 +72,7 @@
 #![allow(explicit_outlives_requirements)]
 #![allow(incomplete_features)]
 #![deny(unsafe_op_in_unsafe_fn)]
-#![cfg_attr(not(bootstrap), feature(rustc_allow_const_fn_unstable))]
+#![feature(rustc_allow_const_fn_unstable)]
 #![cfg_attr(not(test), feature(generator_trait))]
 #![cfg_attr(test, feature(test))]
 #![cfg_attr(test, feature(new_uninit))]
@@ -130,8 +130,7 @@
 #![feature(unicode_internals)]
 #![feature(unsafe_block_in_unsafe_fn)]
 #![feature(unsize)]
-#![cfg_attr(not(bootstrap), feature(unsized_fn_params))]
-#![cfg_attr(bootstrap, feature(unsized_locals))]
+#![feature(unsized_fn_params)]
 #![feature(allocator_internals)]
 #![feature(slice_partition_dedup)]
 #![feature(maybe_uninit_extra, maybe_uninit_slice, maybe_uninit_uninit_array)]
diff --git a/library/alloc/src/raw_vec.rs b/library/alloc/src/raw_vec.rs
index d079d331fa1a9..edab576bea8dd 100644
--- a/library/alloc/src/raw_vec.rs
+++ b/library/alloc/src/raw_vec.rs
@@ -116,8 +116,7 @@ impl<T> RawVec<T, Global> {
 impl<T, A: AllocRef> RawVec<T, A> {
     /// Like `new`, but parameterized over the choice of allocator for
     /// the returned `RawVec`.
-    #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn))]
-    #[cfg_attr(bootstrap, allow_internal_unstable(const_fn))]
+    #[rustc_allow_const_fn_unstable(const_fn)]
     pub const fn new_in(alloc: A) -> Self {
         // `cap: 0` means "unallocated". zero-sized types are ignored.
         Self { ptr: Unique::dangling(), cap: 0, alloc }
diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs
index d67f9c15a1916..0f91ff418e3ac 100644
--- a/library/core/src/lib.rs
+++ b/library/core/src/lib.rs
@@ -63,7 +63,7 @@
 #![warn(missing_debug_implementations)]
 #![allow(explicit_outlives_requirements)]
 #![allow(incomplete_features)]
-#![cfg_attr(not(bootstrap), feature(rustc_allow_const_fn_unstable))]
+#![feature(rustc_allow_const_fn_unstable)]
 #![feature(allow_internal_unstable)]
 #![feature(arbitrary_self_types)]
 #![feature(asm)]
@@ -85,7 +85,7 @@
 #![feature(const_pin)]
 #![feature(const_fn)]
 #![feature(const_fn_union)]
-#![cfg_attr(not(bootstrap), feature(const_impl_trait))]
+#![feature(const_impl_trait)]
 #![feature(const_fn_floating_point_arithmetic)]
 #![feature(const_fn_fn_ptr_basics)]
 #![feature(const_generics)]
@@ -134,9 +134,7 @@
 #![feature(transparent_unions)]
 #![feature(try_blocks)]
 #![feature(unboxed_closures)]
-#![cfg_attr(not(bootstrap), feature(unsized_fn_params))]
-#![cfg_attr(bootstrap, feature(unsized_locals))]
-#![cfg_attr(bootstrap, feature(untagged_unions))]
+#![feature(unsized_fn_params)]
 #![feature(unwind_attributes)]
 #![feature(variant_count)]
 #![feature(tbm_target_feature)]
@@ -290,7 +288,7 @@ pub mod primitive;
     unused_imports,
     unsafe_op_in_unsafe_fn
 )]
-#[cfg_attr(not(bootstrap), allow(non_autolinks))]
+#[allow(non_autolinks)]
 // FIXME: This annotation should be moved into rust-lang/stdarch after clashing_extern_declarations is
 // merged. It currently cannot because bootstrap fails as the lint hasn't been defined yet.
 #[allow(clashing_extern_declarations)]
diff --git a/library/core/src/num/int_macros.rs b/library/core/src/num/int_macros.rs
index 728381b658f7c..289f14a360a34 100644
--- a/library/core/src/num/int_macros.rs
+++ b/library/core/src/num/int_macros.rs
@@ -2047,8 +2047,7 @@ assert_eq!(
             #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
             // SAFETY: const sound because integers are plain old datatypes so we can always
             // transmute them to arrays of bytes
-            #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn_transmute))]
-            #[cfg_attr(bootstrap, allow_internal_unstable(const_fn_transmute))]
+            #[rustc_allow_const_fn_unstable(const_fn_transmute)]
             #[inline]
             pub const fn to_ne_bytes(self) -> [u8; mem::size_of::<Self>()] {
                 // SAFETY: integers are plain old datatypes so we can always transmute them to
@@ -2196,8 +2195,7 @@ fn read_ne_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT),
             #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
             // SAFETY: const sound because integers are plain old datatypes so we can always
             // transmute to them
-            #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn_transmute))]
-            #[cfg_attr(bootstrap, allow_internal_unstable(const_fn_transmute))]
+            #[rustc_allow_const_fn_unstable(const_fn_transmute)]
             #[inline]
             pub const fn from_ne_bytes(bytes: [u8; mem::size_of::<Self>()]) -> Self {
                 // SAFETY: integers are plain old datatypes so we can always transmute to them
diff --git a/library/core/src/num/uint_macros.rs b/library/core/src/num/uint_macros.rs
index adcbbf91433b6..dbdc9c0fb5fcc 100644
--- a/library/core/src/num/uint_macros.rs
+++ b/library/core/src/num/uint_macros.rs
@@ -1805,8 +1805,7 @@ assert_eq!(
             #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
             // SAFETY: const sound because integers are plain old datatypes so we can always
             // transmute them to arrays of bytes
-            #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn_transmute))]
-            #[cfg_attr(bootstrap, allow_internal_unstable(const_fn_transmute))]
+            #[rustc_allow_const_fn_unstable(const_fn_transmute)]
             #[inline]
             pub const fn to_ne_bytes(self) -> [u8; mem::size_of::<Self>()] {
                 // SAFETY: integers are plain old datatypes so we can always transmute them to
@@ -1954,8 +1953,7 @@ fn read_ne_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT),
             #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")]
             // SAFETY: const sound because integers are plain old datatypes so we can always
             // transmute to them
-            #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn_transmute))]
-            #[cfg_attr(bootstrap, allow_internal_unstable(const_fn_transmute))]
+            #[rustc_allow_const_fn_unstable(const_fn_transmute)]
             #[inline]
             pub const fn from_ne_bytes(bytes: [u8; mem::size_of::<Self>()]) -> Self {
                 // SAFETY: integers are plain old datatypes so we can always transmute to them
diff --git a/library/core/src/panicking.rs b/library/core/src/panicking.rs
index 09dd19b8f5f93..25651502510e2 100644
--- a/library/core/src/panicking.rs
+++ b/library/core/src/panicking.rs
@@ -52,7 +52,7 @@ pub fn panic(expr: &'static str) -> ! {
 
 #[inline]
 #[track_caller]
-#[cfg_attr(not(bootstrap), lang = "panic_str")] // needed for const-evaluated panics
+#[lang = "panic_str"] // needed for const-evaluated panics
 pub fn panic_str(expr: &str) -> ! {
     panic_fmt(format_args!("{}", expr));
 }
diff --git a/library/core/src/slice/mod.rs b/library/core/src/slice/mod.rs
index d3af6b9ae6b46..44fe2ca88596f 100644
--- a/library/core/src/slice/mod.rs
+++ b/library/core/src/slice/mod.rs
@@ -88,8 +88,7 @@ impl<T> [T] {
     #[rustc_const_stable(feature = "const_slice_len", since = "1.32.0")]
     #[inline]
     // SAFETY: const sound because we transmute out the length field as a usize (which it must be)
-    #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn_union))]
-    #[cfg_attr(bootstrap, allow_internal_unstable(const_fn_union))]
+    #[rustc_allow_const_fn_unstable(const_fn_union)]
     pub const fn len(&self) -> usize {
         // SAFETY: this is safe because `&[T]` and `FatPtr<T>` have the same layout.
         // Only `std` can make this guarantee.
diff --git a/library/core/src/str/converts.rs b/library/core/src/str/converts.rs
index 952d0598a7c5b..73316433e090f 100644
--- a/library/core/src/str/converts.rs
+++ b/library/core/src/str/converts.rs
@@ -157,8 +157,7 @@ pub fn from_utf8_mut(v: &mut [u8]) -> Result<&mut str, Utf8Error> {
 #[inline]
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_const_unstable(feature = "const_str_from_utf8_unchecked", issue = "75196")]
-#[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn_transmute))]
-#[cfg_attr(bootstrap, allow_internal_unstable(const_fn_transmute))]
+#[rustc_allow_const_fn_unstable(const_fn_transmute)]
 pub const unsafe fn from_utf8_unchecked(v: &[u8]) -> &str {
     // SAFETY: the caller must guarantee that the bytes `v` are valid UTF-8.
     // Also relies on `&str` and `&[u8]` having the same layout.
diff --git a/library/core/src/str/mod.rs b/library/core/src/str/mod.rs
index 23d63a4787efa..604e317110c3e 100644
--- a/library/core/src/str/mod.rs
+++ b/library/core/src/str/mod.rs
@@ -219,8 +219,7 @@ impl str {
     #[rustc_const_stable(feature = "str_as_bytes", since = "1.32.0")]
     #[inline(always)]
     #[allow(unused_attributes)]
-    #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn_transmute))]
-    #[cfg_attr(bootstrap, allow_internal_unstable(const_fn_transmute))]
+    #[rustc_allow_const_fn_unstable(const_fn_transmute)]
     pub const fn as_bytes(&self) -> &[u8] {
         // SAFETY: const sound because we transmute two types with the same layout
         unsafe { mem::transmute(self) }
diff --git a/library/core/src/task/wake.rs b/library/core/src/task/wake.rs
index d3c0d9b784139..b775e022a54b4 100644
--- a/library/core/src/task/wake.rs
+++ b/library/core/src/task/wake.rs
@@ -130,8 +130,7 @@ impl RawWakerVTable {
     #[rustc_promotable]
     #[stable(feature = "futures_api", since = "1.36.0")]
     #[rustc_const_stable(feature = "futures_api", since = "1.36.0")]
-    #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn_fn_ptr_basics))]
-    #[cfg_attr(bootstrap, allow_internal_unstable(const_fn_fn_ptr_basics))]
+    #[rustc_allow_const_fn_unstable(const_fn_fn_ptr_basics)]
     pub const fn new(
         clone: unsafe fn(*const ()) -> RawWaker,
         wake: unsafe fn(*const ()),
diff --git a/library/proc_macro/src/bridge/client.rs b/library/proc_macro/src/bridge/client.rs
index dfe5df965cfac..c6bec5a6fbdc2 100644
--- a/library/proc_macro/src/bridge/client.rs
+++ b/library/proc_macro/src/bridge/client.rs
@@ -401,8 +401,7 @@ fn run_client<A: for<'a, 's> DecodeMut<'a, 's, ()>, R: Encode<()>>(
 }
 
 impl Client<fn(crate::TokenStream) -> crate::TokenStream> {
-    #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn))]
-    #[cfg_attr(bootstrap, allow_internal_unstable(const_fn))]
+    #[rustc_allow_const_fn_unstable(const_fn)]
     pub const fn expand1(f: fn(crate::TokenStream) -> crate::TokenStream) -> Self {
         extern "C" fn run(
             bridge: Bridge<'_>,
@@ -415,8 +414,7 @@ impl Client<fn(crate::TokenStream) -> crate::TokenStream> {
 }
 
 impl Client<fn(crate::TokenStream, crate::TokenStream) -> crate::TokenStream> {
-    #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn))]
-    #[cfg_attr(bootstrap, allow_internal_unstable(const_fn))]
+    #[rustc_allow_const_fn_unstable(const_fn)]
     pub const fn expand2(
         f: fn(crate::TokenStream, crate::TokenStream) -> crate::TokenStream,
     ) -> Self {
@@ -461,8 +459,7 @@ impl ProcMacro {
         }
     }
 
-    #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn))]
-    #[cfg_attr(bootstrap, allow_internal_unstable(const_fn))]
+    #[rustc_allow_const_fn_unstable(const_fn)]
     pub const fn custom_derive(
         trait_name: &'static str,
         attributes: &'static [&'static str],
@@ -471,8 +468,7 @@ impl ProcMacro {
         ProcMacro::CustomDerive { trait_name, attributes, client: Client::expand1(expand) }
     }
 
-    #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn))]
-    #[cfg_attr(bootstrap, allow_internal_unstable(const_fn))]
+    #[rustc_allow_const_fn_unstable(const_fn)]
     pub const fn attr(
         name: &'static str,
         expand: fn(crate::TokenStream, crate::TokenStream) -> crate::TokenStream,
@@ -480,8 +476,7 @@ impl ProcMacro {
         ProcMacro::Attr { name, client: Client::expand2(expand) }
     }
 
-    #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn))]
-    #[cfg_attr(bootstrap, allow_internal_unstable(const_fn))]
+    #[rustc_allow_const_fn_unstable(const_fn)]
     pub const fn bang(
         name: &'static str,
         expand: fn(crate::TokenStream) -> crate::TokenStream,
diff --git a/library/proc_macro/src/bridge/scoped_cell.rs b/library/proc_macro/src/bridge/scoped_cell.rs
index e7c32b10384d4..e1307856175b1 100644
--- a/library/proc_macro/src/bridge/scoped_cell.rs
+++ b/library/proc_macro/src/bridge/scoped_cell.rs
@@ -35,8 +35,7 @@ impl<'a, 'b, T: LambdaL> DerefMut for RefMutL<'a, 'b, T> {
 pub struct ScopedCell<T: LambdaL>(Cell<<T as ApplyL<'static>>::Out>);
 
 impl<T: LambdaL> ScopedCell<T> {
-    #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn))]
-    #[cfg_attr(bootstrap, allow_internal_unstable(const_fn))]
+    #[rustc_allow_const_fn_unstable(const_fn)]
     pub const fn new(value: <T as ApplyL<'static>>::Out) -> Self {
         ScopedCell(Cell::new(value))
     }
diff --git a/library/proc_macro/src/lib.rs b/library/proc_macro/src/lib.rs
index 03733d3b3edac..3ba706b09e859 100644
--- a/library/proc_macro/src/lib.rs
+++ b/library/proc_macro/src/lib.rs
@@ -18,7 +18,7 @@
     test(no_crate_inject, attr(deny(warnings))),
     test(attr(allow(dead_code, deprecated, unused_variables, unused_mut)))
 )]
-#![cfg_attr(not(bootstrap), feature(rustc_allow_const_fn_unstable))]
+#![feature(rustc_allow_const_fn_unstable)]
 #![feature(nll)]
 #![feature(staged_api)]
 #![feature(const_fn)]
diff --git a/library/std/src/ffi/c_str.rs b/library/std/src/ffi/c_str.rs
index 8c6d6c80402fa..60b642a6dba44 100644
--- a/library/std/src/ffi/c_str.rs
+++ b/library/std/src/ffi/c_str.rs
@@ -1266,7 +1266,7 @@ impl CStr {
     /// behavior when `ptr` is used inside the `unsafe` block:
     ///
     /// ```no_run
-    /// # #![allow(unused_must_use)] #![cfg_attr(not(bootstrap), allow(temporary_cstring_as_ptr))]
+    /// # #![allow(unused_must_use)] #![allow(temporary_cstring_as_ptr)]
     /// use std::ffi::CString;
     ///
     /// let ptr = CString::new("Hello").expect("CString::new failed").as_ptr();
diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs
index d2f36309e2daa..6f534ca2a2e0f 100644
--- a/library/std/src/lib.rs
+++ b/library/std/src/lib.rs
@@ -206,7 +206,7 @@
 #![needs_panic_runtime]
 // std may use features in a platform-specific way
 #![allow(unused_features)]
-#![cfg_attr(not(bootstrap), feature(rustc_allow_const_fn_unstable))]
+#![feature(rustc_allow_const_fn_unstable)]
 #![cfg_attr(test, feature(internal_output_capture, print_internals, update_panic_count))]
 #![cfg_attr(
     all(target_vendor = "fortanix", target_env = "sgx"),
@@ -323,7 +323,6 @@
 #![feature(unsafe_block_in_unsafe_fn)]
 #![feature(unsafe_cell_get_mut)]
 #![feature(unsafe_cell_raw_get)]
-#![cfg_attr(bootstrap, feature(untagged_unions))]
 #![feature(unwind_attributes)]
 #![feature(vec_into_raw_parts)]
 #![feature(wake_trait)]
diff --git a/library/std/src/net/ip.rs b/library/std/src/net/ip.rs
index bb3ece4c2739f..04b6f0a5b91b8 100644
--- a/library/std/src/net/ip.rs
+++ b/library/std/src/net/ip.rs
@@ -1043,8 +1043,7 @@ impl Ipv6Addr {
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_stable(feature = "const_ipv6", since = "1.32.0")]
-    #[cfg_attr(not(bootstrap), rustc_allow_const_fn_unstable(const_fn_transmute))]
-    #[cfg_attr(bootstrap, allow_internal_unstable(const_fn_transmute))]
+    #[rustc_allow_const_fn_unstable(const_fn_transmute)]
     pub const fn new(a: u16, b: u16, c: u16, d: u16, e: u16, f: u16, g: u16, h: u16) -> Ipv6Addr {
         let addr16 = [
             a.to_be(),
diff --git a/src/stage0.txt b/src/stage0.txt
index 5b04e0a4985a8..6e05b66c3fe4a 100644
--- a/src/stage0.txt
+++ b/src/stage0.txt
@@ -12,7 +12,7 @@
 # stable release's version number. `date` is the date where the release we're
 # bootstrapping off was released.
 
-date: 2020-10-16
+date: 2020-11-18
 rustc: beta
 
 # We use a nightly rustfmt to format the source because it solves some