Remove #[alloc_error_handler] from the compiler and library

3 files changed, 2 insertions, 76 deletions

diff --git a/library/std/src/alloc.rs b/library/std/src/alloc.rs
index c5a5991cc81..448a8edc291 100644
--- a/library/std/src/alloc.rs
+++ b/library/std/src/alloc.rs
@@ -57,9 +57,8 @@
 #![stable(feature = "alloc_module", since = "1.28.0")]
 
 use core::intrinsics;
+use core::ptr;
 use core::ptr::NonNull;
-use core::sync::atomic::{AtomicPtr, Ordering};
-use core::{mem, ptr};
 
 #[stable(feature = "alloc_module", since = "1.28.0")]
 #[doc(inline)]
@@ -286,76 +285,6 @@ unsafe impl Allocator for System {
     }
 }
 
-static HOOK: AtomicPtr<()> = AtomicPtr::new(ptr::null_mut());
-
-/// Registers a custom allocation error hook, replacing any that was previously registered.
-///
-/// The allocation error hook is invoked when an infallible memory allocation fails, before
-/// the runtime aborts. The default hook prints a message to standard error,
-/// but this behavior can be customized with the [`set_alloc_error_hook`] and
-/// [`take_alloc_error_hook`] functions.
-///
-/// The hook is provided with a `Layout` struct which contains information
-/// about the allocation that failed.
-///
-/// The allocation error hook is a global resource.
-///
-/// # Examples
-///
-/// ```
-/// #![feature(alloc_error_hook)]
-///
-/// use std::alloc::{Layout, set_alloc_error_hook};
-///
-/// fn custom_alloc_error_hook(layout: Layout) {
-///    panic!("memory allocation of {} bytes failed", layout.size());
-/// }
-///
-/// set_alloc_error_hook(custom_alloc_error_hook);
-/// ```
-#[unstable(feature = "alloc_error_hook", issue = "51245")]
-pub fn set_alloc_error_hook(hook: fn(Layout)) {
-    HOOK.store(hook as *mut (), Ordering::SeqCst);
-}
-
-/// Unregisters the current allocation error hook, returning it.
-///
-/// *See also the function [`set_alloc_error_hook`].*
-///
-/// If no custom hook is registered, the default hook will be returned.
-#[unstable(feature = "alloc_error_hook", issue = "51245")]
-pub fn take_alloc_error_hook() -> fn(Layout) {
-    let hook = HOOK.swap(ptr::null_mut(), Ordering::SeqCst);
-    if hook.is_null() { default_alloc_error_hook } else { unsafe { mem::transmute(hook) } }
-}
-
-fn default_alloc_error_hook(layout: Layout) {
-    extern "Rust" {
-        // This symbol is emitted by rustc next to __rust_alloc_error_handler.
-        // Its value depends on the -Zoom={panic,abort} compiler option.
-        static __rust_alloc_error_handler_should_panic: u8;
-    }
-
-    #[allow(unused_unsafe)]
-    if unsafe { __rust_alloc_error_handler_should_panic != 0 } {
-        panic!("memory allocation of {} bytes failed", layout.size());
-    } else {
-        rtprintpanic!("memory allocation of {} bytes failed\n", layout.size());
-    }
-}
-
-#[cfg(not(test))]
-#[doc(hidden)]
-#[alloc_error_handler]
-#[unstable(feature = "alloc_internals", issue = "none")]
-pub fn rust_oom(layout: Layout) -> ! {
-    let hook = HOOK.load(Ordering::SeqCst);
-    let hook: fn(Layout) =
-        if hook.is_null() { default_alloc_error_hook } else { unsafe { mem::transmute(hook) } };
-    hook(layout);
-    crate::process::abort()
-}
-
 #[cfg(not(test))]
 #[doc(hidden)]
 #[allow(unused_attributes)]
diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs
index 109d6331ade..900df71919b 100644
--- a/library/std/src/lib.rs
+++ b/library/std/src/lib.rs
@@ -236,7 +236,6 @@
 //
 // Language features:
 // tidy-alphabetical-start
-#![feature(alloc_error_handler)]
 #![feature(allocator_internals)]
 #![feature(allow_internal_unsafe)]
 #![feature(allow_internal_unstable)]
diff --git a/library/std/src/prelude/v1.rs b/library/std/src/prelude/v1.rs
index 2aefd7c513d..4f325a70b18 100644
--- a/library/std/src/prelude/v1.rs
+++ b/library/std/src/prelude/v1.rs
@@ -60,9 +60,7 @@ pub use core::prelude::v1::{RustcDecodable, RustcEncodable};
 // Do not `doc(no_inline)` so that they become doc items on their own
 // (no public module for them to be re-exported from).
 #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
-pub use core::prelude::v1::{
-    alloc_error_handler, bench, derive, global_allocator, test, test_case,
-};
+pub use core::prelude::v1::{bench, derive, global_allocator, test, test_case};
 
 #[unstable(feature = "derive_const", issue = "none")]
 pub use core::prelude::v1::derive_const;