Auto merge of #103188 - JohnTitor:rollup-pwilam1, r=JohnTitor

Rollup of 6 pull requests

Successful merges:

 - #103023 (Adding `fuchsia-ignore` and `needs-unwind` to compiler test cases)
 - #103142 (Make diagnostic for unsatisfied `Termination` bounds more precise)
 - #103154 (Fix typo in `ReverseSearcher` docs)
 - #103159 (Remove the redundant `Some(try_opt!(..))` in `checked_pow`)
 - #103163 (Remove all uses of array_assume_init)
 - #103168 (Stabilize asm_sym)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

alloc/src/lib.rs

@@ -125,9 +125,9 @@
 #![feature(iter_advance_by)]
 #![feature(iter_next_chunk)]
 #![feature(layout_for_ptr)]
-#![feature(maybe_uninit_array_assume_init)]
 #![feature(maybe_uninit_slice)]
 #![feature(maybe_uninit_uninit_array)]
+#![feature(maybe_uninit_uninit_array_transpose)]
 #![cfg_attr(test, feature(new_uninit))]
 #![feature(nonnull_slice_from_raw_parts)]
 #![feature(pattern)]

alloc/src/vec/into_iter.rs

@@ -223,7 +223,7 @@ impl<T, A: Allocator> Iterator for IntoIter<T, A> {
 
             self.ptr = self.ptr.wrapping_byte_add(N);
             // Safety: ditto
-            return Ok(unsafe { MaybeUninit::array_assume_init(raw_ary) });
+            return Ok(unsafe { raw_ary.transpose().assume_init() });
         }
 
         if len < N {
@@ -241,7 +241,7 @@ impl<T, A: Allocator> Iterator for IntoIter<T, A> {
         return unsafe {
             ptr::copy_nonoverlapping(self.ptr, raw_ary.as_mut_ptr() as *mut T, N);
             self.ptr = self.ptr.add(N);
-            Ok(MaybeUninit::array_assume_init(raw_ary))
+            Ok(raw_ary.transpose().assume_init())
         };
     }
 

core/src/array/iter.rs

@@ -104,8 +104,7 @@ impl<T, const N: usize> IntoIter<T, N> {
     ///
     /// ```
     /// #![feature(array_into_iter_constructors)]
-    ///
-    /// #![feature(maybe_uninit_array_assume_init)]
+    /// #![feature(maybe_uninit_uninit_array_transpose)]
     /// #![feature(maybe_uninit_uninit_array)]
     /// use std::array::IntoIter;
     /// use std::mem::MaybeUninit;
@@ -134,7 +133,7 @@ impl<T, const N: usize> IntoIter<T, N> {
     ///     }
     ///
     ///     // SAFETY: We've initialized all N items
-    ///     unsafe { Ok(MaybeUninit::array_assume_init(buffer)) }
+    ///     unsafe { Ok(buffer.transpose().assume_init()) }
     /// }
     ///
     /// let r: [_; 4] = next_chunk(&mut (10..16)).unwrap();

core/src/array/mod.rs

@@ -912,7 +912,7 @@ where
 
     mem::forget(guard);
     // SAFETY: All elements of the array were populated in the loop above.
-    let output = unsafe { MaybeUninit::array_assume_init(array) };
+    let output = unsafe { array.transpose().assume_init() };
     Ok(Try::from_output(output))
 }
 

core/src/num/int_macros.rs

@@ -869,7 +869,7 @@ macro_rules! int_impl {
             // Deal with the final bit of the exponent separately, since
             // squaring the base afterwards is not necessary and may cause a
             // needless overflow.
-            Some(try_opt!(acc.checked_mul(base)))
+            acc.checked_mul(base)
         }
 
         /// Saturating integer addition. Computes `self + rhs`, saturating at the numeric

core/src/num/uint_macros.rs

@@ -990,7 +990,7 @@ macro_rules! uint_impl {
             // squaring the base afterwards is not necessary and may cause a
             // needless overflow.
 
-            Some(try_opt!(acc.checked_mul(base)))
+            acc.checked_mul(base)
         }
 
         /// Saturating integer addition. Computes `self + rhs`, saturating at

core/src/str/pattern.rs

@@ -267,7 +267,7 @@ pub unsafe trait Searcher<'a> {
 /// The index ranges returned by this trait are not required
 /// to exactly match those of the forward search in reverse.
 ///
-/// For the reason why this trait is marked unsafe, see them
+/// For the reason why this trait is marked unsafe, see the
 /// parent trait [`Searcher`].
 pub unsafe trait ReverseSearcher<'a>: Searcher<'a> {
     /// Performs the next search step starting from the back.

core/tests/lib.rs

@@ -49,8 +49,8 @@
 #![feature(slice_from_ptr_range)]
 #![feature(split_as_slice)]
 #![feature(maybe_uninit_uninit_array)]
-#![feature(maybe_uninit_array_assume_init)]
 #![feature(maybe_uninit_write_slice)]
+#![feature(maybe_uninit_uninit_array_transpose)]
 #![feature(min_specialization)]
 #![feature(numfmt)]
 #![feature(step_trait)]

core/tests/mem.rs

@@ -163,18 +163,18 @@ fn assume_init_good() {
 
 #[test]
 fn uninit_array_assume_init() {
-    let mut array: [MaybeUninit<i16>; 5] = MaybeUninit::uninit_array();
+    let mut array = [MaybeUninit::<i16>::uninit(); 5];
     array[0].write(3);
     array[1].write(1);
     array[2].write(4);
     array[3].write(1);
     array[4].write(5);
 
-    let array = unsafe { MaybeUninit::array_assume_init(array) };
+    let array = unsafe { array.transpose().assume_init() };
 
     assert_eq!(array, [3, 1, 4, 1, 5]);
 
-    let [] = unsafe { MaybeUninit::<!>::array_assume_init([]) };
+    let [] = unsafe { [MaybeUninit::<!>::uninit(); 0].transpose().assume_init() };
 }
 
 #[test]

std/src/process.rs

@@ -2154,8 +2154,16 @@ pub fn id() -> u32 {
 #[cfg_attr(not(test), lang = "termination")]
 #[stable(feature = "termination_trait_lib", since = "1.61.0")]
 #[rustc_on_unimplemented(
-    message = "`main` has invalid return type `{Self}`",
-    label = "`main` can only return types that implement `{Termination}`"
+    on(
+        all(not(bootstrap), cause = "MainFunctionType"),
+        message = "`main` has invalid return type `{Self}`",
+        label = "`main` can only return types that implement `{Termination}`"
+    ),
+    on(
+        bootstrap,
+        message = "`main` has invalid return type `{Self}`",
+        label = "`main` can only return types that implement `{Termination}`"
+    )
 )]
 pub trait Termination {
     /// Is called to get the representation of the value as status code.