Auto merge of rust-lang#62355 - Centril:rollup-xnxtcgm, r=Centril

Rollup of 16 pull requests

Successful merges:

 - rust-lang#62039 (Remove needless lifetimes (rustc))
 - rust-lang#62173 (rename InterpretCx -> InterpCx)
 - rust-lang#62240 (wfcheck: resolve the type-vars in `AdtField` types)
 - rust-lang#62249 (Use mem::take instead of mem::replace with default)
 - rust-lang#62252 (Update mem::replace example to not be identical to mem::take)
 - rust-lang#62258 (syntax: Unsupport `foo! bar { ... }` macros in the parser)
 - rust-lang#62268 (Clean up inherent_impls)
 - rust-lang#62287 (Use link attributes on extern "C" blocks with llvm-libuwind)
 - rust-lang#62295 (miri realloc: do not require giving old size+align)
 - rust-lang#62297 (refactor check_for_substitution)
 - rust-lang#62316 (When possible without changing semantics, implement Iterator::last in terms of DoubleEndedIterator::next_back for types in liballoc and libcore.)
 - rust-lang#62317 (Migrate `compile-pass` annotations to `build-pass`)
 - rust-lang#62337 (Fix bucket in CPU usage script)
 - rust-lang#62344 (simplify Option::get_or_insert)
 - rust-lang#62346 (enable a few more tests in Miri and update the comment for others)
 - rust-lang#62351 (remove bogus example from drop_in_place)

Failed merges:

r? @ghost

Author: bors

src/etc/cpu-usage-over-time-plot.sh

@@ -16,7 +16,7 @@
 
 set -ex
 
-bucket=rust-lang-ci-evalazure
+bucket=rust-lang-ci2
 commit=$1
 builder=$2
 

src/liballoc/boxed.rs

@@ -728,6 +728,14 @@ impl<I: Iterator + ?Sized> Iterator for Box<I> {
         (**self).nth(n)
     }
 }
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<I: Iterator + Sized> Iterator for Box<I> {
+    fn last(self) -> Option<I::Item> where I: Sized {
+        (*self).last()
+    }
+}
+
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<I: DoubleEndedIterator + ?Sized> DoubleEndedIterator for Box<I> {
     fn next_back(&mut self) -> Option<I::Item> {

src/liballoc/collections/binary_heap.rs

@@ -1035,6 +1035,11 @@ impl<'a, T> Iterator for Iter<'a, T> {
     fn size_hint(&self) -> (usize, Option<usize>) {
         self.iter.size_hint()
     }
+
+    #[inline]
+    fn last(self) -> Option<&'a T> {
+        self.iter.last()
+    }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]

src/liballoc/collections/btree/map.rs

@@ -770,8 +770,8 @@ impl<K: Ord, V> BTreeMap<K, V> {
         }
 
         // First, we merge `self` and `other` into a sorted sequence in linear time.
-        let self_iter = mem::replace(self, BTreeMap::new()).into_iter();
-        let other_iter = mem::replace(other, BTreeMap::new()).into_iter();
+        let self_iter = mem::take(self).into_iter();
+        let other_iter = mem::take(other).into_iter();
         let iter = MergeIter {
             left: self_iter.peekable(),
             right: other_iter.peekable(),
@@ -1193,6 +1193,10 @@ impl<'a, K: 'a, V: 'a> Iterator for Iter<'a, K, V> {
     fn size_hint(&self) -> (usize, Option<usize>) {
         (self.length, Some(self.length))
     }
+
+    fn last(mut self) -> Option<(&'a K, &'a V)> {
+        self.next_back()
+    }
 }
 
 #[stable(feature = "fused", since = "1.26.0")]
@@ -1253,6 +1257,10 @@ impl<'a, K: 'a, V: 'a> Iterator for IterMut<'a, K, V> {
     fn size_hint(&self) -> (usize, Option<usize>) {
         (self.length, Some(self.length))
     }
+
+    fn last(mut self) -> Option<(&'a K, &'a mut V)> {
+        self.next_back()
+    }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -1421,6 +1429,10 @@ impl<'a, K, V> Iterator for Keys<'a, K, V> {
     fn size_hint(&self) -> (usize, Option<usize>) {
         self.inner.size_hint()
     }
+
+    fn last(mut self) -> Option<&'a K> {
+        self.next_back()
+    }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -1458,6 +1470,10 @@ impl<'a, K, V> Iterator for Values<'a, K, V> {
     fn size_hint(&self) -> (usize, Option<usize>) {
         self.inner.size_hint()
     }
+
+    fn last(mut self) -> Option<&'a V> {
+        self.next_back()
+    }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -1495,6 +1511,10 @@ impl<'a, K, V> Iterator for Range<'a, K, V> {
             unsafe { Some(self.next_unchecked()) }
         }
     }
+
+    fn last(mut self) -> Option<(&'a K, &'a V)> {
+        self.next_back()
+    }
 }
 
 #[stable(feature = "map_values_mut", since = "1.10.0")]
@@ -1508,6 +1528,10 @@ impl<'a, K, V> Iterator for ValuesMut<'a, K, V> {
     fn size_hint(&self) -> (usize, Option<usize>) {
         self.inner.size_hint()
     }
+
+    fn last(mut self) -> Option<&'a mut V> {
+        self.next_back()
+    }
 }
 
 #[stable(feature = "map_values_mut", since = "1.10.0")]
@@ -1626,6 +1650,10 @@ impl<'a, K, V> Iterator for RangeMut<'a, K, V> {
             unsafe { Some(self.next_unchecked()) }
         }
     }
+
+    fn last(mut self) -> Option<(&'a K, &'a mut V)> {
+        self.next_back()
+    }
 }
 
 impl<'a, K, V> RangeMut<'a, K, V> {

src/liballoc/collections/btree/set.rs

@@ -1019,6 +1019,9 @@ impl<'a, T> Iterator for Iter<'a, T> {
     fn size_hint(&self) -> (usize, Option<usize>) {
         self.iter.size_hint()
     }
+    fn last(mut self) -> Option<&'a T> {
+        self.next_back()
+    }
 }
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<'a, T> DoubleEndedIterator for Iter<'a, T> {
@@ -1073,6 +1076,10 @@ impl<'a, T> Iterator for Range<'a, T> {
     fn next(&mut self) -> Option<&'a T> {
         self.iter.next().map(|(k, _)| k)
     }
+
+    fn last(mut self) -> Option<&'a T> {
+        self.next_back()
+    }
 }
 
 #[stable(feature = "btree_range", since = "1.17.0")]

src/liballoc/collections/linked_list.rs

@@ -708,7 +708,7 @@ impl<T> LinkedList<T> {
         let len = self.len();
         assert!(at <= len, "Cannot split off at a nonexistent index");
         if at == 0 {
-            return mem::replace(self, Self::new());
+            return mem::take(self);
         } else if at == len {
             return Self::new();
         }
@@ -832,6 +832,11 @@ impl<'a, T> Iterator for Iter<'a, T> {
     fn size_hint(&self) -> (usize, Option<usize>) {
         (self.len, Some(self.len))
     }
+
+    #[inline]
+    fn last(mut self) -> Option<&'a T> {
+        self.next_back()
+    }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -881,6 +886,11 @@ impl<'a, T> Iterator for IterMut<'a, T> {
     fn size_hint(&self) -> (usize, Option<usize>) {
         (self.len, Some(self.len))
     }
+
+    #[inline]
+    fn last(mut self) -> Option<&'a mut T> {
+        self.next_back()
+    }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]

src/liballoc/collections/vec_deque.rs

@@ -2206,6 +2206,11 @@ impl<'a, T> Iterator for Iter<'a, T> {
         self.tail = self.head - iter.len();
         final_res
     }
+
+    #[inline]
+    fn last(mut self) -> Option<&'a T> {
+        self.next_back()
+    }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -2319,6 +2324,11 @@ impl<'a, T> Iterator for IterMut<'a, T> {
         accum = front.iter_mut().fold(accum, &mut f);
         back.iter_mut().fold(accum, &mut f)
     }
+
+    #[inline]
+    fn last(mut self) -> Option<&'a mut T> {
+        self.next_back()
+    }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]

src/liballoc/lib.rs

@@ -112,6 +112,7 @@
 #![feature(maybe_uninit_extra, maybe_uninit_slice, maybe_uninit_array)]
 #![feature(alloc_layout_extra)]
 #![feature(try_trait)]
+#![feature(mem_take)]
 
 // Allow testing this library
 

src/liballoc/str.rs

@@ -203,7 +203,7 @@ impl ToOwned for str {
     }
 
     fn clone_into(&self, target: &mut String) {
-        let mut b = mem::replace(target, String::new()).into_bytes();
+        let mut b = mem::take(target).into_bytes();
         self.as_bytes().clone_into(&mut b);
         *target = unsafe { String::from_utf8_unchecked(b) }
     }

src/liballoc/string.rs

@@ -2385,6 +2385,11 @@ impl Iterator for Drain<'_> {
     fn size_hint(&self) -> (usize, Option<usize>) {
         self.iter.size_hint()
     }
+
+    #[inline]
+    fn last(mut self) -> Option<char> {
+        self.next_back()
+    }
 }
 
 #[stable(feature = "drain", since = "1.6.0")]