step cfgs

Author: Mark-Simulacrum

compiler/rustc_ast/src/lib.rs

@@ -16,7 +16,6 @@
 #![feature(box_patterns)]
 #![feature(if_let_guard)]
 #![feature(let_chains)]
-#![cfg_attr(bootstrap, feature(min_specialization))]
 #![feature(never_type)]
 #![feature(negative_impls)]
 #![feature(stmt_expr_attributes)]

compiler/rustc_errors/src/lib.rs

@@ -7,7 +7,6 @@
 #![allow(internal_features)]
 #![allow(rustc::diagnostic_outside_of_impl)]
 #![allow(rustc::untranslatable_diagnostic)]
-#![cfg_attr(bootstrap, feature(min_specialization))]
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![doc(rust_logo)]
 #![feature(array_windows)]

compiler/rustc_hir/src/lib.rs

@@ -5,7 +5,6 @@
 #![feature(associated_type_defaults)]
 #![feature(closure_track_caller)]
 #![feature(let_chains)]
-#![cfg_attr(bootstrap, feature(min_specialization))]
 #![feature(never_type)]
 #![feature(rustc_attrs)]
 #![feature(variant_count)]

compiler/rustc_hir_analysis/src/lib.rs

@@ -68,7 +68,6 @@ This API is completely unstable and subject to change.
 #![feature(is_sorted)]
 #![feature(iter_intersperse)]
 #![feature(let_chains)]
-#![cfg_attr(bootstrap, feature(min_specialization))]
 #![feature(never_type)]
 #![feature(lazy_cell)]
 #![feature(slice_partition_dedup)]

compiler/rustc_hir_typeck/src/lib.rs

@@ -5,7 +5,6 @@
 #![feature(try_blocks)]
 #![feature(never_type)]
 #![feature(box_patterns)]
-#![cfg_attr(bootstrap, feature(min_specialization))]
 #![feature(control_flow_enum)]
 
 #[macro_use]

compiler/rustc_infer/src/lib.rs

@@ -25,7 +25,6 @@
 #![feature(let_chains)]
 #![feature(if_let_guard)]
 #![feature(iterator_try_collect)]
-#![cfg_attr(bootstrap, feature(min_specialization))]
 #![feature(try_blocks)]
 #![recursion_limit = "512"] // For rustdoc
 

compiler/rustc_middle/src/lib.rs

@@ -24,8 +24,7 @@
 
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![doc(rust_logo)]
-#![cfg_attr(bootstrap, feature(exhaustive_patterns))]
-#![cfg_attr(not(bootstrap), feature(min_exhaustive_patterns))]
+#![feature(min_exhaustive_patterns)]
 #![feature(rustdoc_internals)]
 #![feature(allocator_api)]
 #![feature(array_windows)]

compiler/rustc_mir_build/src/lib.rs

@@ -9,7 +9,6 @@
 #![feature(box_patterns)]
 #![feature(if_let_guard)]
 #![feature(let_chains)]
-#![cfg_attr(bootstrap, feature(min_specialization))]
 #![feature(try_blocks)]
 
 #[macro_use]

compiler/rustc_mir_dataflow/src/lib.rs

@@ -2,7 +2,6 @@
 #![feature(box_patterns)]
 #![feature(exact_size_is_empty)]
 #![feature(let_chains)]
-#![cfg_attr(bootstrap, feature(min_specialization))]
 #![feature(try_blocks)]
 
 #[macro_use]

compiler/rustc_mir_transform/src/lib.rs

@@ -8,7 +8,6 @@
 #![feature(is_sorted)]
 #![feature(let_chains)]
 #![feature(map_try_insert)]
-#![cfg_attr(bootstrap, feature(min_specialization))]
 #![feature(never_type)]
 #![feature(option_get_or_insert_default)]
 #![feature(round_char_boundary)]

compiler/rustc_target/src/lib.rs

@@ -9,13 +9,11 @@
 
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![doc(rust_logo)]
-#![cfg_attr(bootstrap, feature(exhaustive_patterns))]
-#![cfg_attr(not(bootstrap), feature(min_exhaustive_patterns))]
+#![feature(min_exhaustive_patterns)]
 #![feature(rustdoc_internals)]
 #![feature(assert_matches)]
 #![feature(iter_intersperse)]
 #![feature(let_chains)]
-#![cfg_attr(bootstrap, feature(min_specialization))]
 #![feature(rustc_attrs)]
 #![feature(step_trait)]
 #![allow(internal_features)]

compiler/rustc_trait_selection/src/lib.rs

@@ -26,7 +26,6 @@
 #![feature(option_take_if)]
 #![feature(never_type)]
 #![feature(type_alias_impl_trait)]
-#![cfg_attr(bootstrap, feature(min_specialization))]
 #![recursion_limit = "512"] // For rustdoc
 
 #[macro_use]

library/alloc/src/alloc.rs

@@ -51,7 +51,7 @@ extern "Rust" {
 #[derive(Copy, Clone, Default, Debug)]
 #[cfg(not(test))]
 // the compiler needs to know when a Box uses the global allocator vs a custom one
-#[cfg_attr(not(bootstrap), lang = "global_alloc_ty")]
+#[lang = "global_alloc_ty"]
 pub struct Global;
 
 #[cfg(test)]
@@ -387,8 +387,7 @@ pub const fn handle_alloc_error(layout: Layout) -> ! {
     }
 
     #[cfg(not(feature = "panic_immediate_abort"))]
-    #[cfg_attr(not(bootstrap), allow(unused_unsafe))] // on bootstrap bump, remove unsafe block
-    unsafe {
+    {
         core::intrinsics::const_eval_select((layout,), ct_error, rt_error)
     }
 

library/core/src/convert/mod.rs

@@ -396,7 +396,7 @@ pub trait AsMut<T: ?Sized> {
 /// For example, take this code:
 ///
 /// ```
-/// # #![cfg_attr(not(bootstrap), allow(non_local_definitions))]
+/// # #![allow(non_local_definitions)]
 /// struct Wrapper<T>(Vec<T>);
 /// impl<T> From<Wrapper<T>> for Vec<T> {
 ///     fn from(w: Wrapper<T>) -> Vec<T> {

library/core/src/ffi/c_str.rs

@@ -438,13 +438,7 @@ impl CStr {
             unsafe { &*(bytes as *const [u8] as *const CStr) }
         }
 
-        #[cfg_attr(not(bootstrap), allow(unused_unsafe))] // on bootstrap bump, remove unsafe block
-        // SAFETY: The const and runtime versions have identical behavior
-        // unless the safety contract of `from_bytes_with_nul_unchecked` is
-        // violated, which is UB.
-        unsafe {
-            intrinsics::const_eval_select((bytes,), const_impl, rt_impl)
-        }
+        intrinsics::const_eval_select((bytes,), const_impl, rt_impl)
     }
 
     /// Returns the inner pointer to this C string.
@@ -759,7 +753,7 @@ const unsafe fn const_strlen(ptr: *const c_char) -> usize {
         unsafe { strlen(s) }
     }
 
-    #[cfg_attr(not(bootstrap), allow(unused_unsafe))] // on bootstrap bump, remove unsafe block
+    #[allow(unused_unsafe)] // on bootstrap bump, remove unsafe block
     // SAFETY: the two functions always provide equivalent functionality
     unsafe {
         intrinsics::const_eval_select((ptr,), strlen_ct, strlen_rt)

library/core/src/hash/mod.rs

@@ -454,7 +454,7 @@ pub trait Hasher {
     /// ```
     /// #![feature(hasher_prefixfree_extras)]
     /// # // Stubs to make the `impl` below pass the compiler
-    /// # #![cfg_attr(not(bootstrap), allow(non_local_definitions))]
+    /// # #![allow(non_local_definitions)]
     /// # struct MyCollection<T>(Option<T>);
     /// # impl<T> MyCollection<T> {
     /// #     fn len(&self) -> usize { todo!() }

library/core/src/intrinsics.rs

@@ -84,9 +84,6 @@ pub unsafe fn drop_in_place<T: ?Sized>(to_drop: *mut T) {
     unsafe { crate::ptr::drop_in_place(to_drop) }
 }
 
-#[cfg(bootstrap)]
-pub use self::r#try as catch_unwind;
-
 extern "rust-intrinsic" {
     // N.B., these intrinsics take raw pointers because they mutate aliased
     // memory, which is not valid for either `&` or `&mut`.
@@ -965,8 +962,7 @@ extern "rust-intrinsic" {
 #[rustc_const_stable(feature = "const_assume", since = "1.77.0")]
 #[rustc_nounwind]
 #[unstable(feature = "core_intrinsics", issue = "none")]
-#[cfg_attr(not(bootstrap), rustc_intrinsic)]
-#[cfg_attr(bootstrap, inline)]
+#[rustc_intrinsic]
 pub const unsafe fn assume(b: bool) {
     if !b {
         // SAFETY: the caller must guarantee the argument is never `false`
@@ -987,9 +983,8 @@ pub const unsafe fn assume(b: bool) {
 /// This intrinsic does not have a stable counterpart.
 #[rustc_const_unstable(feature = "const_likely", issue = "none")]
 #[unstable(feature = "core_intrinsics", issue = "none")]
-#[cfg_attr(not(bootstrap), rustc_intrinsic)]
+#[rustc_intrinsic]
 #[rustc_nounwind]
-#[cfg_attr(bootstrap, inline)]
 pub const fn likely(b: bool) -> bool {
     b
 }
@@ -1007,9 +1002,8 @@ pub const fn likely(b: bool) -> bool {
 /// This intrinsic does not have a stable counterpart.
 #[rustc_const_unstable(feature = "const_likely", issue = "none")]
 #[unstable(feature = "core_intrinsics", issue = "none")]
-#[cfg_attr(not(bootstrap), rustc_intrinsic)]
+#[rustc_intrinsic]
 #[rustc_nounwind]
-#[cfg_attr(bootstrap, inline)]
 pub const fn unlikely(b: bool) -> bool {
     b
 }
@@ -1919,39 +1913,34 @@ extern "rust-intrinsic" {
     /// This intrinsic does not have a stable counterpart.
     #[rustc_nounwind]
     #[rustc_safe_intrinsic]
-    #[cfg(not(bootstrap))]
     pub fn fadd_algebraic<T: Copy>(a: T, b: T) -> T;
 
     /// Float subtraction that allows optimizations based on algebraic rules.
     ///
     /// This intrinsic does not have a stable counterpart.
     #[rustc_nounwind]
     #[rustc_safe_intrinsic]
-    #[cfg(not(bootstrap))]
     pub fn fsub_algebraic<T: Copy>(a: T, b: T) -> T;
 
     /// Float multiplication that allows optimizations based on algebraic rules.
     ///
     /// This intrinsic does not have a stable counterpart.
     #[rustc_nounwind]
     #[rustc_safe_intrinsic]
-    #[cfg(not(bootstrap))]
     pub fn fmul_algebraic<T: Copy>(a: T, b: T) -> T;
 
     /// Float division that allows optimizations based on algebraic rules.
     ///
     /// This intrinsic does not have a stable counterpart.
     #[rustc_nounwind]
     #[rustc_safe_intrinsic]
-    #[cfg(not(bootstrap))]
     pub fn fdiv_algebraic<T: Copy>(a: T, b: T) -> T;
 
     /// Float remainder that allows optimizations based on algebraic rules.
     ///
     /// This intrinsic does not have a stable counterpart.
     #[rustc_nounwind]
     #[rustc_safe_intrinsic]
-    #[cfg(not(bootstrap))]
     pub fn frem_algebraic<T: Copy>(a: T, b: T) -> T;
 
     /// Convert with LLVM’s fptoui/fptosi, which may return undef for values out of range
@@ -2407,14 +2396,8 @@ extern "rust-intrinsic" {
     ///
     /// The stable version of this intrinsic is `std::panic::catch_unwind`.
     #[rustc_nounwind]
-    #[cfg(not(bootstrap))]
     pub fn catch_unwind(try_fn: fn(*mut u8), data: *mut u8, catch_fn: fn(*mut u8, *mut u8)) -> i32;
 
-    /// For bootstrap only, see `catch_unwind`.
-    #[rustc_nounwind]
-    #[cfg(bootstrap)]
-    pub fn r#try(try_fn: fn(*mut u8), data: *mut u8, catch_fn: fn(*mut u8, *mut u8)) -> i32;
-
     /// Emits a `!nontemporal` store according to LLVM (see their docs).
     /// Probably will never become stable.
     ///
@@ -2518,9 +2501,9 @@ extern "rust-intrinsic" {
     #[cfg(bootstrap)]
     pub fn vtable_align(ptr: *const ()) -> usize;
 
-    #[cfg(bootstrap)]
     #[rustc_const_unstable(feature = "const_eval_select", issue = "none")]
-    #[cfg_attr(not(bootstrap), rustc_safe_intrinsic)]
+    #[rustc_safe_intrinsic]
+    #[cfg(bootstrap)]
     pub fn const_eval_select<ARG: Tuple, F, G, RET>(
         arg: ARG,
         called_in_const: F,
@@ -2650,8 +2633,7 @@ where
 #[rustc_const_unstable(feature = "is_val_statically_known", issue = "none")]
 #[rustc_nounwind]
 #[unstable(feature = "core_intrinsics", issue = "none")]
-#[cfg_attr(not(bootstrap), rustc_intrinsic)]
-#[cfg_attr(bootstrap, inline)]
+#[rustc_intrinsic]
 pub const fn is_val_statically_known<T: Copy>(_arg: T) -> bool {
     false
 }
@@ -2670,7 +2652,7 @@ pub const fn is_val_statically_known<T: Copy>(_arg: T) -> bool {
 #[rustc_const_unstable(feature = "ub_checks", issue = "none")]
 #[unstable(feature = "core_intrinsics", issue = "none")]
 #[inline(always)]
-#[cfg_attr(not(bootstrap), rustc_intrinsic)]
+#[rustc_intrinsic]
 pub(crate) const fn check_library_ub() -> bool {
     cfg!(debug_assertions)
 }
@@ -2686,7 +2668,7 @@ pub(crate) const fn check_library_ub() -> bool {
 #[rustc_const_unstable(feature = "ub_checks", issue = "none")]
 #[unstable(feature = "core_intrinsics", issue = "none")]
 #[inline(always)]
-#[cfg_attr(not(bootstrap), rustc_intrinsic)]
+#[rustc_intrinsic]
 pub(crate) const fn check_language_ub() -> bool {
     cfg!(debug_assertions)
 }
@@ -2702,8 +2684,7 @@ pub(crate) const fn check_language_ub() -> bool {
 #[rustc_const_unstable(feature = "const_heap", issue = "79597")]
 #[unstable(feature = "core_intrinsics", issue = "none")]
 #[rustc_nounwind]
-#[cfg_attr(not(bootstrap), rustc_intrinsic)]
-#[cfg_attr(bootstrap, inline)]
+#[rustc_intrinsic]
 pub const unsafe fn const_allocate(_size: usize, _align: usize) -> *mut u8 {
     // const eval overrides this function, but runtime code should always just return null pointers.
     crate::ptr::null_mut()
@@ -2722,8 +2703,7 @@ pub const unsafe fn const_allocate(_size: usize, _align: usize) -> *mut u8 {
 #[rustc_const_unstable(feature = "const_heap", issue = "79597")]
 #[unstable(feature = "core_intrinsics", issue = "none")]
 #[rustc_nounwind]
-#[cfg_attr(not(bootstrap), rustc_intrinsic)]
-#[cfg_attr(bootstrap, inline)]
+#[rustc_intrinsic]
 pub const unsafe fn const_deallocate(_ptr: *mut u8, _size: usize, _align: usize) {}
 
 /// `ptr` must point to a vtable.
@@ -2799,15 +2779,6 @@ pub unsafe fn vtable_align(_ptr: *const ()) -> usize {
 macro_rules! assert_unsafe_precondition {
     ($kind:ident, $message:expr, ($($name:ident:$ty:ty = $arg:expr),*$(,)?) => $e:expr $(,)?) => {
         {
-            // #[cfg(bootstrap)] (this comment)
-            // When the standard library is compiled with debug assertions, we want the check to inline for better performance.
-            // This is important when working on the compiler, which is compiled with debug assertions locally.
-            // When not compiled with debug assertions (so the precompiled std) we outline the check to minimize the compile
-            // time impact when debug assertions are disabled.
-            // The proper solution to this is the `#[rustc_no_mir_inline]` below, but we still want decent performance for cfg(bootstrap).
-            #[cfg_attr(all(debug_assertions, bootstrap), inline(always))]
-            #[cfg_attr(all(not(debug_assertions), bootstrap), inline(never))]
-
             // This check is inlineable, but not by the MIR inliner.
             // The reason for this is that the MIR inliner is in an exceptionally bad position
             // to think about whether or not to inline this. In MIR, this call is gated behind `debug_assertions`,
@@ -2816,8 +2787,8 @@ macro_rules! assert_unsafe_precondition {
             //
             // LLVM on the other hand sees the constant branch, so if it's `false`, it can immediately delete it without
             // inlining the check. If it's `true`, it can inline it and get significantly better performance.
-            #[cfg_attr(not(bootstrap), rustc_no_mir_inline)]
-            #[cfg_attr(not(bootstrap), inline)]
+            #[rustc_no_mir_inline]
+            #[inline]
             #[rustc_nounwind]
             #[rustc_const_unstable(feature = "ub_checks", issue = "none")]
             const fn precondition_check($($name:$ty),*) {
@@ -2885,13 +2856,7 @@ pub(crate) const fn is_nonoverlapping(
         true
     }
 
-    #[cfg_attr(not(bootstrap), allow(unused_unsafe))] // on bootstrap bump, remove unsafe block
-    // SAFETY: This function's precondition is equivalent to that of `const_eval_select`.
-    // Programs which do not execute UB will only see this function return `true`, which makes the
-    // const and runtime implementation indistinguishable.
-    unsafe {
-        const_eval_select((src, dst, size, count), comptime, runtime)
-    }
+    const_eval_select((src, dst, size, count), comptime, runtime)
 }
 
 /// Copies `count * size_of::<T>()` bytes from `src` to `dst`. The source
@@ -3208,9 +3173,5 @@ pub(crate) const fn miri_promise_symbolic_alignment(ptr: *const (), align: usize
 
     const fn compiletime(_ptr: *const (), _align: usize) {}
 
-    #[cfg_attr(not(bootstrap), allow(unused_unsafe))] // on bootstrap bump, remove unsafe block
-    // SAFETY: the extra behavior at runtime is for UB checks only.
-    unsafe {
-        const_eval_select((ptr, align), compiletime, runtime);
-    }
+    const_eval_select((ptr, align), compiletime, runtime);
 }

library/core/src/intrinsics/simd.rs

@@ -2,11 +2,7 @@
 //!
 //! In this module, a "vector" is any `repr(simd)` type.
 
-// Temporary macro while we switch the ABI from "platform-intrinsics" to "intrinsics".
-#[rustfmt::skip]
-macro_rules! declare_intrinsics {
-($abi:tt) => {
-extern $abi {
+extern "rust-intrinsic" {
     /// Insert an element into a vector, returning the updated vector.
     ///
     /// `T` must be a vector with element type `U`.
@@ -659,10 +655,3 @@ extern $abi {
     #[rustc_nounwind]
     pub fn simd_flog<T>(a: T) -> T;
 }
-}
-}
-
-#[cfg(bootstrap)]
-declare_intrinsics!("platform-intrinsic");
-#[cfg(not(bootstrap))]
-declare_intrinsics!("rust-intrinsic");