Auto merge of #51543 - SimonSapin:oom, r=SimonSapin

Rename OOM to allocation error

The acronym is not descriptive unless one has seen it before.

* Rename the `oom` function to `handle_alloc_error`. It was **stabilized in 1.28**, so if we do this at all we need to land it this cycle.
* Rename `set_oom_hook` to `set_alloc_error_hook`
* Rename `take_oom_hook` to `take_alloc_error_hook`

Bikeshed: `on` v.s. `for`, `alloc` v.s. `allocator`, `error` v.s. `failure`

src/libstd/alloc.rs

@@ -88,38 +88,38 @@ pub use alloc_system::System;
 
 static HOOK: AtomicPtr<()> = AtomicPtr::new(ptr::null_mut());
 
-/// Registers a custom OOM hook, replacing any that was previously registered.
+/// Registers a custom allocation error hook, replacing any that was previously registered.
 ///
-/// The OOM hook is invoked when an infallible memory allocation fails, before
+/// 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_oom_hook`] and
-/// [`take_oom_hook`] functions.
+/// 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 OOM hook is a global resource.
-#[unstable(feature = "oom_hook", issue = "51245")]
-pub fn set_oom_hook(hook: fn(Layout)) {
+/// The allocation error hook is a global resource.
+#[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 OOM hook, returning it.
+/// Unregisters the current allocation error hook, returning it.
 ///
-/// *See also the function [`set_oom_hook`].*
+/// *See also the function [`set_alloc_error_hook`].*
 ///
 /// If no custom hook is registered, the default hook will be returned.
-#[unstable(feature = "oom_hook", issue = "51245")]
-pub fn take_oom_hook() -> fn(Layout) {
+#[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_oom_hook
+        default_alloc_error_hook
     } else {
         unsafe { mem::transmute(hook) }
     }
 }
 
-fn default_oom_hook(layout: Layout) {
+fn default_alloc_error_hook(layout: Layout) {
     dumb_print(format_args!("memory allocation of {} bytes failed", layout.size()));
 }
 
@@ -130,7 +130,7 @@ fn default_oom_hook(layout: Layout) {
 pub extern fn rust_oom(layout: Layout) -> ! {
     let hook = HOOK.load(Ordering::SeqCst);
     let hook: fn(Layout) = if hook.is_null() {
-        default_oom_hook
+        default_alloc_error_hook
     } else {
         unsafe { mem::transmute(hook) }
     };

src/libstd/collections/hash/table.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use alloc::{Global, Alloc, Layout, LayoutErr, CollectionAllocErr, oom};
+use alloc::{Global, Alloc, Layout, LayoutErr, CollectionAllocErr, handle_alloc_error};
 use hash::{BuildHasher, Hash, Hasher};
 use marker;
 use mem::{size_of, needs_drop};
@@ -699,7 +699,7 @@ impl<K, V> RawTable<K, V> {
         // point into it.
         let (layout, _) = calculate_layout::<K, V>(capacity)?;
         let buffer = Global.alloc(layout).map_err(|e| match fallibility {
-            Infallible => oom(layout),
+            Infallible => handle_alloc_error(layout),
             Fallible => e,
         })?;