Add a package for rust version 1.77.0.

Pkgsrc changes:
 * Adapt checksums and patches.

Upstream chnages:

Version 1.77.0 (2024-03-21)
==========================

- [Reveal opaque types within the defining body for exhaustiveness checking.]
  (rust-lang/rust#116821)
- [Stabilize C-string literals.]
  (rust-lang/rust#117472)
- [Stabilize THIR unsafeck.]
  (rust-lang/rust#117673)
- [Add lint `static_mut_refs` to warn on references to mutable statics.]
  (rust-lang/rust#117556)
- [Support async recursive calls (as long as they have indirection).]
  (rust-lang/rust#117703)
- [Undeprecate lint `unstable_features` and make use of it in the compiler.]
  (rust-lang/rust#118639)
- [Make inductive cycles in coherence ambiguous always.]
  (rust-lang/rust#118649)
- [Get rid of type-driven traversal in const-eval interning]
  (rust-lang/rust#119044),
  only as a [future compatiblity lint]
  (rust-lang/rust#122204) for now.
- [Deny braced macro invocations in let-else.]
  (rust-lang/rust#119062)

Compiler
--------

- [Include lint `soft_unstable` in future breakage reports.]
  (rust-lang/rust#116274)
- [Make `i128` and `u128` 16-byte aligned on x86-based targets.]
  (rust-lang/rust#116672)
- [Use `--verbose` in diagnostic output.]
  (rust-lang/rust#119129)
- [Improve spacing between printed tokens.]
  (rust-lang/rust#120227)
- [Merge the `unused_tuple_struct_fields` lint into `dead_code`.]
  (rust-lang/rust#118297)
- [Error on incorrect implied bounds in well-formedness check]
  (rust-lang/rust#118553),
  with a temporary exception for Bevy.
- [Fix coverage instrumentation/reports for non-ASCII source code.]
  (rust-lang/rust#119033)
- [Fix `fn`/`const` items implied bounds and well-formedness check.]
  (rust-lang/rust#120019)
- [Promote `riscv32{im|imafc}-unknown-none-elf` targets to tier 2.]
  (rust-lang/rust#118704)
- Add several new tier 3 targets:
  - [`aarch64-unknown-illumos`]
    (rust-lang/rust#112936)
  - [`hexagon-unknown-none-elf`]
    (rust-lang/rust#117601)
  - [`riscv32imafc-esp-espidf`]
    (rust-lang/rust#119738)
  - [`riscv32im-risc0-zkvm-elf`]
    (rust-lang/rust#117958)

Refer to Rust's [platform support page][platform-support-doc]
for more information on Rust's tiered platform support.

Libraries
---------

- [Implement `From<&[T; N]>` for `Cow<[T]>`.]
  (rust-lang/rust#113489)
- [Remove special-case handling of `vec.split_off
  (0)`.](rust-lang/rust#119917)

Stabilized APIs
---------------

- [`array::each_ref`]
  (https://doc.rust-lang.org/stable/std/primitive.array.html#method.each_ref)
- [`array::each_mut`]
  (https://doc.rust-lang.org/stable/std/primitive.array.html#method.each_mut)
- [`core::net`]
  (https://doc.rust-lang.org/stable/core/net/index.html)
- [`f32::round_ties_even`]
  (https://doc.rust-lang.org/stable/std/primitive.f32.html#method.round_ties_even)
- [`f64::round_ties_even`]
  (https://doc.rust-lang.org/stable/std/primitive.f64.html#method.round_ties_even)
- [`mem::offset_of!`]
  (https://doc.rust-lang.org/stable/std/mem/macro.offset_of.html)
- [`slice::first_chunk`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.first_chunk)
- [`slice::first_chunk_mut`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.first_chunk_mut)
- [`slice::split_first_chunk`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_first_chunk)
- [`slice::split_first_chunk_mut`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_first_chunk_mut)
- [`slice::last_chunk`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.last_chunk)
- [`slice::last_chunk_mut`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.last_chunk_mut)
- [`slice::split_last_chunk`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_last_chunk)
- [`slice::split_last_chunk_mut`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.split_last_chunk_mut)
- [`slice::chunk_by`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.chunk_by)
- [`slice::chunk_by_mut`]
  (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.chunk_by_mut)
- [`Bound::map`]
  (https://doc.rust-lang.org/stable/std/ops/enum.Bound.html#method.map)
- [`File::create_new`]
  (https://doc.rust-lang.org/stable/std/fs/struct.File.html#method.create_new)
- [`Mutex::clear_poison`]
  (https://doc.rust-lang.org/stable/std/sync/struct.Mutex.html#method.clear_poison)
- [`RwLock::clear_poison`]
  (https://doc.rust-lang.org/stable/std/sync/struct.RwLock.html#method.clear_poison)

Cargo
-----

- [Extend the build directive syntax with `cargo::`.]
  (rust-lang/cargo#12201)
- [Stabilize metadata `id` format as `PackageIDSpec`.]
  (rust-lang/cargo#12914)
- [Pull out as `cargo-util-schemas` as a crate.]
  (rust-lang/cargo#13178)
- [Strip all debuginfo when debuginfo is not requested.]
  (rust-lang/cargo#13257)
- [Inherit jobserver from env for all kinds of runners.]
  (rust-lang/cargo#12776)
- [Deprecate rustc plugin support in cargo.]
  (rust-lang/cargo#13248)

Rustdoc
-----

- [Allows links in markdown headings.]
  (rust-lang/rust#117662)
- [Search for tuples and unit by type with `()`.]
  (rust-lang/rust#118194)
- [Clean up the source sidebar's hide button.]
  (rust-lang/rust#119066)
- [Prevent JS injection from `localStorage`.]
  (rust-lang/rust#120250)

Misc
----

- [Recommend version-sorting for all sorting in style guide.]
  (rust-lang/rust#115046)

Internal Changes
----------------

These changes do not affect any public interfaces of Rust, but they represent
significant improvements to the performance or internals of rustc and related
tools.

- [Add more weirdness to `weird-exprs.rs`.]
  (rust-lang/rust#119028)

rust177/DESCR

@@ -0,0 +1,13 @@
+Rust is a systems programming language focused on three goals: safety,
+speed, and concurrency.  It maintains these goals without having a
+garbage collector, making it a useful language for a number of use cases
+other languages aren't good at: embedding in other languages, programs
+with specific space and time requirements, and writing low-level code,
+like device drivers and operating systems.
+
+It improves on current languages targeting this space by having a number
+of compile-time safety checks that produce no runtime overhead, while
+eliminating all data races.  Rust also aims to achieve "zero-cost
+abstractions" even though some of these abstractions feel like those of
+a high-level language.  Even then, Rust still allows precise control
+like a low-level language would.

rust177/HOWTO-BOOTSTRAP

@@ -0,0 +1,85 @@
+How to build a rust bootstrap kit using pkgsrc
+----------------------------------------------
+
+A rust bootstrap kit is simply a pre-compiled binary of rust and
+the rust standard library, and contains the "rust" and "rust-std"
+build results, found in
+
+   work/rustc-<version>/build/dist/
+as
+   rust-<version>-<target>.tar.xz
+and
+   rust-std-<version>-<target>.tar.xz
+
+These result files are produced when the "dist" build target is
+used, ref. BUILD_TARGET.   For a normal native build of the rust
+pkgsrc package, the default BUILD_TARGET is "build", not "dist".
+
+There are two possible ways to produce a bootstrap kit:
+
+1) a native build.  This requires minimum preparation, except
+   possibly for setting rust.BUILD_TARGET to "dist" via e.g.
+   /etc/mk.conf.  Note that on NetBSD, using the "BUILD_TARGET" ==
+   "dist" results in the "rust-cargo-static" option being set, ref.
+   options.mk.  This is so that the resulting bootstrap kits are
+   built with mostly-static linking, reducing the run-time dependencies
+   of the bootstrap kits.
+
+2) a cross-build.  This requires a bit of preparation:
+
+   For each target you want to cross-build rust for, you need
+     - the cross toolchain resulting from "build.sh tools" for
+       the intended target
+     - an OS distribution extracted, including the comp.tgz
+       set so that the target's include files can be used
+     - for 32-bit ports, the "libatomic" package needs to be
+       available.  I'm sure there's a clever and long-winded
+       use of pkg_install which can be used to effect this;
+       I on my hand have always just extracted the tgz file
+       and done the minimal cleanup of the "cruft" files
+       which are part of the package meta-data.
+     - Pick a root directory for the target, e.g. /u/i386.
+       Below this directory place the "tools" containing
+       the cross-compiler in a "tools" sub-directory.
+       Similarly, the extracted OS distribution in the "dest"
+       sub-directory.
+
+   There are two methods available for doing the cross-compile:
+
+   a) Using the "cross.mk" file.  For an i386 build against i586, the
+      following settings should be active:
+
+CROSS_ROOT=            /u/i386
+MAKE_ENV+=             CROSS_ROOT=${CROSS_ROOT}
+GNU_CROSS_TARGET=      i486--netbsdelf
+MAKE_ENV+=             GNU_CROSS_TARGET=${GNU_CROSS_TARGET}
+TARGET=                i586-unknown-netbsd
+SCRIPTS=               ${WRKDIR}/scripts
+CONFIGURE_ARGS+=       --host=${TARGET}
+CONFIGURE_ARGS+=       --target=${TARGET}
+CONFIGURE_ARGS+=       --set=target.${TARGET}.cc=${SCRIPTS}/gcc-wrap
+CONFIGURE_ARGS+=       --set=target.${TARGET}.cxx=${SCRIPTS}/c++-wrap
+CONFIGURE_ARGS+=       --set=target.${TARGET}.linker=${SCRIPTS}/gcc-wrap
+CONFIGURE_ARGS+=       --set=target.${TARGET}.ar=${CROSS_ROOT}/tools/bin/${GNU_CROSS_TARGET}-ar
+
+      Then doing a "make" will cross-build rust, including the LLVM
+      embedded in the rust distribution, ref. the defaulting of that
+      option when TARGET is defined ref. options.mk.
+
+      Note that when TARGET is set, the default build target for
+      the rust makefile becomes "dist", so there's no need to set
+      rust.BUILD_TARGET for cross-builds.
+
+   b) Using the "do-cross.mk" Makefile.  This will attempt to
+      cross-build rust for all the targets listed in the SHORT_TARGETS
+      variable in that file.  Overriding the root directories for
+      the various targets can be done by making your own "local-roots.mk"
+      file, ref. "do-cross.mk".
+
+      This will create a "dist" subdirectory in the rust pkgsrc
+      directory, and the bootstrap kits for each architecture, plus
+      the library source kit will be placed in this directory.
+
+The bootstrap kits can then be placed in /usr/pkgsrc/distfiles, and
+be used by the "next" rust version, where you can use "make makesum"
+to compute the updated checksums for the bootstrap kits.