Auto merge of #64160 - Centril:rollup-vrfj1pt, r=Centril

Rollup of 15 pull requests

Successful merges:

 - #62860 (Stabilize checked_duration_since for 1.38.0)
 - #63549 (Rev::rposition counts from the wrong end)
 - #63985 (Stabilize pin_into_inner in 1.39.0)
 - #64005 (Add a `Place::is_indirect` method to determine whether a `Place` contains a `Deref` projection)
 - #64031 (Harden `param_attrs` test wrt. usage of a proc macro `#[attr]`)
 - #64038 (Check impl trait substs when checking for recursive types)
 - #64043 (Add some more tests for underscore imports)
 - #64092 (Update xLTO compatibility table in rustc book.)
 - #64110 (Refer to "`self` type" instead of "receiver type")
 - #64120 (Move path parsing earlier)
 - #64123 (Added warning around code with reference to uninit bytes)
 - #64128 (unused_parens: account for or-patterns and `&(mut x)`)
 - #64141 (Minimize uses of `LocalInternedString`)
 - #64142 (Fix doc links in `std::cmp` module)
 - #64148 (fix a few typos in comments)

Failed merges:

r? @ghost

3 files changed, 10 insertions, 5 deletions

diff --git a/src/libstd/io/mod.rs b/src/libstd/io/mod.rs
index 5060f368229..0386dbd490d 100644
--- a/src/libstd/io/mod.rs
+++ b/src/libstd/io/mod.rs
@@ -371,6 +371,14 @@ where
     loop {
         if g.len == g.buf.len() {
             unsafe {
+                // FIXME(danielhenrymantilla): #42788
+                //
+                //   - This creates a (mut) reference to a slice of
+                //     _uninitialized_ integers, which is **undefined behavior**
+                //
+                //   - Only the standard library gets to soundly "ignore" this,
+                //     based on its privileged knowledge of unstable rustc
+                //     internals;
                 g.buf.reserve(reservation_size(r));
                 let capacity = g.buf.capacity();
                 g.buf.set_len(capacity);
diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
index c3882bacf87..71050b0dcd1 100644
--- a/src/libstd/lib.rs
+++ b/src/libstd/lib.rs
@@ -244,7 +244,6 @@
 #![feature(cfg_target_has_atomic)]
 #![feature(cfg_target_thread_local)]
 #![feature(char_error_internals)]
-#![feature(checked_duration_since)]
 #![feature(clamp)]
 #![feature(compiler_builtins_lib)]
 #![feature(concat_idents)]
diff --git a/src/libstd/time.rs b/src/libstd/time.rs
index 98371b9ba3d..d59085cd44a 100644
--- a/src/libstd/time.rs
+++ b/src/libstd/time.rs
@@ -221,7 +221,6 @@ impl Instant {
     /// # Examples
     ///
     /// ```no_run
-    /// #![feature(checked_duration_since)]
     /// use std::time::{Duration, Instant};
     /// use std::thread::sleep;
     ///
@@ -231,7 +230,7 @@ impl Instant {
     /// println!("{:?}", new_now.checked_duration_since(now));
     /// println!("{:?}", now.checked_duration_since(new_now)); // None
     /// ```
-    #[unstable(feature = "checked_duration_since", issue = "58402")]
+    #[stable(feature = "checked_duration_since", since = "1.39.0")]
     pub fn checked_duration_since(&self, earlier: Instant) -> Option<Duration> {
         self.0.checked_sub_instant(&earlier.0)
     }
@@ -242,7 +241,6 @@ impl Instant {
     /// # Examples
     ///
     /// ```no_run
-    /// #![feature(checked_duration_since)]
     /// use std::time::{Duration, Instant};
     /// use std::thread::sleep;
     ///
@@ -252,7 +250,7 @@ impl Instant {
     /// println!("{:?}", new_now.saturating_duration_since(now));
     /// println!("{:?}", now.saturating_duration_since(new_now)); // 0ns
     /// ```
-    #[unstable(feature = "checked_duration_since", issue = "58402")]
+    #[stable(feature = "checked_duration_since", since = "1.39.0")]
     pub fn saturating_duration_since(&self, earlier: Instant) -> Duration {
         self.checked_duration_since(earlier).unwrap_or(Duration::new(0, 0))
     }