Auto merge of #40368 - arielb1:rollup, r=arielb1

Rollup of 20 pull requests

- Successful merges: #40154, #40222, #40226, #40237, #40254, #40258, #40265, #40268, #40279, #40283, #40292, #40293, #40296, #40316, #40321, #40325, #40326, #40327, #40333, #40335
- Failed merges:

2 files changed, 20 insertions, 7 deletions

diff --git a/src/libcore/macros.rs b/src/libcore/macros.rs
index 66a923f8e58..b22f7fa1707 100644
--- a/src/libcore/macros.rs
+++ b/src/libcore/macros.rs
@@ -32,11 +32,11 @@ macro_rules! panic {
 
 /// Ensure that a boolean expression is `true` at runtime.
 ///
-/// This will invoke the `panic!` macro if the provided expression cannot be
+/// This will invoke the [`panic!`] macro if the provided expression cannot be
 /// evaluated to `true` at runtime.
 ///
 /// Assertions are always checked in both debug and release builds, and cannot
-/// be disabled. See `debug_assert!` for assertions that are not enabled in
+/// be disabled. See [`debug_assert!`] for assertions that are not enabled in
 /// release builds by default.
 ///
 /// Unsafe code relies on `assert!` to enforce run-time invariants that, if
@@ -48,6 +48,8 @@ macro_rules! panic {
 /// This macro has a second version, where a custom panic message can
 /// be provided with or without arguments for formatting.
 ///
+/// [`panic!`]: macro.panic.html
+/// [`debug_assert!`]: macro.debug_assert.html
 /// [testing]: ../book/testing.html
 ///
 /// # Examples
@@ -88,9 +90,11 @@ macro_rules! assert {
 /// On panic, this macro will print the values of the expressions with their
 /// debug representations.
 ///
-/// Like `assert!()`, this macro has a second version, where a custom
+/// Like [`assert!()`], this macro has a second version, where a custom
 /// panic message can be provided.
 ///
+/// [`assert!()`]: macro.assert.html
+///
 /// # Examples
 ///
 /// ```
@@ -134,6 +138,8 @@ macro_rules! assert_eq {
 /// Like `assert!()`, this macro has a second version, where a custom
 /// panic message can be provided.
 ///
+/// [`assert!`]: macro.assert.html
+///
 /// # Examples
 ///
 /// ```
@@ -171,13 +177,13 @@ macro_rules! assert_ne {
 
 /// Ensure that a boolean expression is `true` at runtime.
 ///
-/// This will invoke the `panic!` macro if the provided expression cannot be
+/// This will invoke the [`panic!`] macro if the provided expression cannot be
 /// evaluated to `true` at runtime.
 ///
-/// Like `assert!`, this macro also has a second version, where a custom panic
+/// Like [`assert!`], this macro also has a second version, where a custom panic
 /// message can be provided.
 ///
-/// Unlike `assert!`, `debug_assert!` statements are only enabled in non
+/// Unlike [`assert!`], `debug_assert!` statements are only enabled in non
 /// optimized builds by default. An optimized build will omit all
 /// `debug_assert!` statements unless `-C debug-assertions` is passed to the
 /// compiler. This makes `debug_assert!` useful for checks that are too
@@ -187,10 +193,13 @@ macro_rules! assert_ne {
 /// An unchecked assertion allows a program in an inconsistent state to keep
 /// running, which might have unexpected consequences but does not introduce
 /// unsafety as long as this only happens in safe code. The performance cost
-/// of assertions, is however, not measurable in general. Replacing `assert!`
+/// of assertions, is however, not measurable in general. Replacing [`assert!`]
 /// with `debug_assert!` is thus only encouraged after thorough profiling, and
 /// more importantly, only in safe code!
 ///
+/// [`panic!`]: macro.panic.html
+/// [`assert!`]: macro.assert.html
+///
 /// # Examples
 ///
 /// ```
diff --git a/src/libcore/ptr.rs b/src/libcore/ptr.rs
index 02851c224e2..260fdab9d58 100644
--- a/src/libcore/ptr.rs
+++ b/src/libcore/ptr.rs
@@ -191,6 +191,10 @@ pub unsafe fn read_unaligned<T>(src: *const T) -> T {
 /// allocations or resources, so care must be taken not to overwrite an object
 /// that should be dropped.
 ///
+/// It does not immediately drop the contents of `src` either; it is rather
+/// *moved* into the memory location `dst` and will be dropped whenever that
+/// location goes out of scope.
+///
 /// This is appropriate for initializing uninitialized memory, or overwriting
 /// memory that has previously been `read` from.
 ///