Auto merge of #75921 - pietroalbini:beta-next, r=Mark-Simulacrum

[beta] Prepare beta 1.47.0

Also backported the release notes change.

r? @Mark-Simulacrum

RELEASES.md

@@ -68,7 +68,19 @@ Compatibility Notes
 - [Rustc now correctly relates the lifetime of an existential associated
   type.][71896] This fixes some edge cases where `rustc` would erroneously allow
   you to pass a shorter lifetime than expected.
-
+- [Rustc now dynamically links to `libz` (also called `zlib`) on Linux.][74420]
+  The library will need to be installed for `rustc` to work, even though we
+  expect it to be already available on most systems.
+- [Tests annotated with `#[should_panic]` are broken on ARMv7 while running
+  under QEMU.][74820]
+- [Pretty printing of some tokens in procedural macros changed.][75453] The
+  exact output returned by rustc's pretty printing is an unstable
+  implementation detail: we recommend any macro relying on it to switch to a
+  more robust parsing system.
+
+[75453]: https://github.com/rust-lang/rust/issues/75453/
+[74820]: https://github.com/rust-lang/rust/issues/74820/
+[74420]: https://github.com/rust-lang/rust/issues/74420/
 [74109]: https://github.com/rust-lang/rust/pull/74109/
 [74150]: https://github.com/rust-lang/rust/pull/74150/
 [73862]: https://github.com/rust-lang/rust/pull/73862/

src/ci/run.sh

@@ -63,7 +63,7 @@ fi
 #
 # FIXME: need a scheme for changing this `nightly` value to `beta` and `stable`
 #        either automatically or manually.
-export RUST_RELEASE_CHANNEL=nightly
+export RUST_RELEASE_CHANNEL=beta
 
 # Always set the release channel for bootstrap; this is normally not important (i.e., only dist
 # builds would seem to matter) but in practice bootstrap wants to know whether we're targeting

src/stage0.txt

@@ -12,15 +12,15 @@
 # source tarball for a stable release you'll likely see `1.x.0` for rustc and
 # `0.(x+1).0` for Cargo where they were released on `date`.
 
-date: 2020-07-16
-rustc: beta
-cargo: beta
+date: 2020-08-24
+rustc: 1.46.0
+cargo: 0.47.0
 
 # We use a nightly rustfmt to format the source because it solves some
 # bootstrapping issues with use of new syntax in this repo. If you're looking at
 # the beta/stable branch, this key should be omitted, as we don't want to depend
 # on rustfmt from nightly there.
-rustfmt: nightly-2020-07-12
+#rustfmt: nightly-2020-07-12
 
 # When making a stable release the process currently looks like:
 #
@@ -40,4 +40,4 @@ rustfmt: nightly-2020-07-12
 # looking at a beta source tarball and it's uncommented we'll shortly comment it
 # out.
 
-#dev: 1
+dev: 1