rust178: Add a package for rust version 1.78.0.

Pkgsrc changes:
 * Adapt checksums and patches, some have beene intregrated upstream.

Upstream chnages:

Version 1.78.0 (2024-05-02)
===========================

Language
--------
- [Stabilize `#[cfg(target_abi = ...)]`]
  (rust-lang/rust#119590)
- [Stabilize the `#[diagnostic]` namespace and
  `#[diagnostic::on_unimplemented]` attribute]
  (rust-lang/rust#119888)
- [Make async-fn-in-trait implementable with concrete signatures]
  (rust-lang/rust#120103)
- [Make matching on NaN a hard error, and remove the rest of
  `illegal_floating_point_literal_pattern`]
  (rust-lang/rust#116284)
- [static mut: allow mutable reference to arbitrary types, not just
  slices and arrays]
  (rust-lang/rust#117614)
- [Extend `invalid_reference_casting` to include references casting
  to bigger memory layout]
  (rust-lang/rust#118983)
- [Add `non_contiguous_range_endpoints` lint for singleton gaps
  after exclusive ranges]
  (rust-lang/rust#118879)
- [Add `wasm_c_abi` lint for use of older wasm-bindgen versions]
  (rust-lang/rust#117918)
  This lint currently only works when using Cargo.
- [Update `indirect_structural_match` and `pointer_structural_match`
  lints to match RFC]
  (rust-lang/rust#120423)
- [Make non-`PartialEq`-typed consts as patterns a hard error]
  (rust-lang/rust#120805)
- [Split `refining_impl_trait` lint into `_reachable`, `_internal` variants]
  (rust-lang/rust#121720)
- [Remove unnecessary type inference when using associated types
  inside of higher ranked `where`-bounds]
  (rust-lang/rust#119849)
- [Weaken eager detection of cyclic types during type inference]
  (rust-lang/rust#119989)
- [`trait Trait: Auto {}`: allow upcasting from `dyn Trait` to `dyn Auto`]
  (rust-lang/rust#119338)

Compiler
--------

- [Made `INVALID_DOC_ATTRIBUTES` lint deny by default]
  (rust-lang/rust#111505)
- [Increase accuracy of redundant `use` checking]
  (rust-lang/rust#117772)
- [Suggest moving definition if non-found macro_rules! is defined later]
  (rust-lang/rust#121130)
- [Lower transmutes from int to pointer type as gep on null]
  (rust-lang/rust#121282)

Target changes:

- [Windows tier 1 targets now require at least Windows 10]
  (rust-lang/rust#115141)
 - [Enable CMPXCHG16B, SSE3, SAHF/LAHF and 128-bit Atomics in tier 1 Windows]
  (rust-lang/rust#120820)
- [Add `wasm32-wasip1` tier 2 (without host tools) target]
  (rust-lang/rust#120468)
- [Add `wasm32-wasip2` tier 3 target]
  (rust-lang/rust#119616)
- [Rename `wasm32-wasi-preview1-threads` to `wasm32-wasip1-threads`]
  (rust-lang/rust#122170)
- [Add `arm64ec-pc-windows-msvc` tier 3 target]
  (rust-lang/rust#119199)
- [Add `armv8r-none-eabihf` tier 3 target for the Cortex-R52]
  (rust-lang/rust#110482)
- [Add `loongarch64-unknown-linux-musl` tier 3 target]
  (rust-lang/rust#121832)

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

Libraries
---------

- [Bump Unicode to version 15.1.0, regenerate tables]
  (rust-lang/rust#120777)
- [Make align_offset, align_to well-behaved in all cases]
  (rust-lang/rust#121201)
- [PartialEq, PartialOrd: document expectations for transitive chains]
  (rust-lang/rust#115386)
- [Optimize away poison guards when std is built with panic=abort]
  (rust-lang/rust#100603)
- [Replace pthread `RwLock` with custom implementation]
  (rust-lang/rust#110211)
- [Implement unwind safety for Condvar on all platforms]
  (rust-lang/rust#121768)
- [Add ASCII fast-path for `char::is_grapheme_extended`]
  (rust-lang/rust#121138)

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

- [`impl Read for &Stdin`]
  (https://doc.rust-lang.org/stable/std/io/struct.Stdin.html#impl-Read-for-%26Stdin)
- [Accept non `'static` lifetimes for several `std::error::Error`
  related implementations] (rust-lang/rust#113833)
- [Make `impl<Fd: AsFd>` impl take `?Sized`]
  (rust-lang/rust#114655)
- [`impl From<TryReserveError> for io::Error`]
  (https://doc.rust-lang.org/stable/std/io/struct.Error.html#impl-From%3CTryReserveError%3E-for-Error)

These APIs are now stable in const contexts:

- [`Barrier::new()`]
  (https://doc.rust-lang.org/stable/std/sync/struct.Barrier.html#method.new)

Cargo
-----

- [Stabilize lockfile v4](rust-lang/cargo#12852)
- [Respect `rust-version` when generating lockfile]
  (rust-lang/cargo#12861)
- [Control `--charset` via auto-detecting config value]
  (rust-lang/cargo#13337)
- [Support `target.<triple>.rustdocflags` officially]
  (rust-lang/cargo#13197)
- [Stabilize global cache data tracking]
  (rust-lang/cargo#13492)

Misc
----

- [rustdoc: add `--test-builder-wrapper` arg to support wrappers
  such as RUSTC_WRAPPER when building doctests]
  (rust-lang/rust#114651)

Compatibility Notes
-------------------

- [Many unsafe precondition checks now run for user code with debug
  assertions enabled] (rust-lang/rust#120594)
  This change helps users catch undefined behavior in their code,
  though the details of how much is checked are generally not
  stable.
- [riscv only supports split_debuginfo=off for now]
  (rust-lang/rust#120518)
- [Consistently check bounds on hidden types of `impl Trait`]
  (rust-lang/rust#121679)
- [Change equality of higher ranked types to not rely on subtyping]
  (rust-lang/rust#118247)
- [When called, additionally check bounds on normalized function return type]
  (rust-lang/rust#118882)
- [Expand coverage for `arithmetic_overflow` lint]
  (rust-lang/rust#119432)

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.

- [Update to LLVM 18](rust-lang/rust#120055)
- [Build `rustc` with 1CGU on `x86_64-pc-windows-msvc`]
  (rust-lang/rust#112267)
- [Build `rustc` with 1CGU on `x86_64-apple-darwin`]
  (rust-lang/rust#112268)
- [Introduce `run-make` V2 infrastructure, a `run_make_support`
  library and port over 2 tests as example]
  (rust-lang/rust#113026)
- [Windows: Implement condvar, mutex and rwlock using futex]
  (rust-lang/rust#121956)

rust178/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.

rust178/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.