Update note about unstable split-debuginfo flag.
split-debuginfo was effectively stabilized in #98051. The note about it requiring `-Z unstable-options` is no longer accurate.
The rules for when it is gated and when it is supported are somewhat complex. I considered removing the note entirely, or making it more generic, but opted to instead try to summarize the current state.
Add a tier 3 target for the Sony PlayStation 1
This adds a tier 3 target, `mipsel-sony-psx`, for the Sony PlayStation 1. I've tested it pretty thoroughly with [this SDK](https://github.com/ayrtonm/psx-sdk-rs) I wrote for it.
From the [tier 3 target policy](https://doc.rust-lang.org/rustc/target-tier-policy.html#tier-3-target-policy) (I've omitted the subpoints for brevity, but read over everything)
> A tier 3 target must have a designated developer or developers (the "target maintainers") on record to be CCed when issues arise regarding the target. (The mechanism to track and CC such developers may evolve over time.)
I'd be the designated developer
> Targets must use naming consistent with any existing targets; for instance, a target for the same CPU or OS as an existing Rust target should use the same name for that CPU or OS. Targets should normally use the same names and naming conventions as used elsewhere in the broader ecosystem beyond Rust (such as in other toolchains), unless they have a very good reason to diverge. Changing the name of a target can be highly disruptive, especially once the target reaches a higher tier, so getting the name right is important even for a tier 3 target.
The target name follows the conventions of the existing PSP target (`mipsel-sony-psp`) and uses `psx` following the convention of the broader [PlayStation homebrew community](https://psx-spx.consoledev.net/).
> Tier 3 targets may have unusual requirements to build or use, but must not create legal issues or impose onerous legal terms for the Rust project or for Rust developers or users.
No legal issues with this target.
> Neither this policy nor any decisions made regarding targets shall create any binding agreement or estoppel by any party. If any member of an approving Rust team serves as one of the maintainers of a target, or has any legal or employment requirement (explicit or implicit) that might affect their decisions regarding a target, they must recuse themselves from any approval decisions regarding the target's tier status, though they may otherwise participate in discussions.
👍
> Tier 3 targets should attempt to implement as much of the standard libraries as possible and appropriate (core for most targets, alloc for targets that can support dynamic memory allocation, std for targets with an operating system or equivalent layer of system-provided functionality), but may leave some code unimplemented (either unavailable or stubbed out as appropriate), whether because the target makes it impossible to implement or challenging to implement. The authors of pull requests are not obligated to avoid calling any portions of the standard library on the basis of a tier 3 target not implementing those portions.
The psx supports `core` and `alloc`, but will likely not support `std` anytime soon.
> The target must provide documentation for the Rust community explaining how to build for the target, using cross-compilation if possible. If the target supports running binaries, or running tests (even if they do not pass), the documentation must explain how to run such binaries or tests for the target, using emulation if possible or dedicated hardware if necessary.
This target has an SDK and a `cargo-psx` tool for formatting binaries as psx executables. Documentation and examples are provided in the [psx-sdk-rs README](https://github.com/ayrtonm/psx-sdk-rs#psx-sdk-rs), the SDK and cargo tool are both available through crates.io and docs.rs has [SDK documentation](https://docs.rs/psx/latest/psx/).
> Tier 3 targets must not impose burden on the authors of pull requests, or other developers in the community, to maintain the target. In particular, do not post comments (automated or manual) on a PR that derail or suggest a block on the PR based on a tier 3 target. Do not send automated messages or notifications (via any medium, including via `@)` to a PR author or others involved with a PR regarding a tier 3 target, unless they have opted into such messages.
👍
> Patches adding or updating tier 3 targets must not break any existing tier 2 or tier 1 target, and must not knowingly break another tier 3 target without approval of either the compiler team or the maintainers of the other tier 3 target.
No problem
Enable varargs support for calling conventions other than C or cdecl
This patch makes it possible to use varargs for calling conventions,
which are either based on C (efiapi) or C is based on them (sysv64 and win64).
Also pinging ``@phlopsi,`` because he noticed first this oversight when writing a library for UEFI.
rustdoc: add missing URL redirect
https://github.com/rust-lang/rust/pull/94753 missed some redirect settings, and one of the missing URL shows up in an error message. This PR adds those redirects.
Update books
## reference
4 commits in f6ed74f582bddcec73f753eafaab3749c4f7df61..4ea7c5def38ac81df33a9e48e5637a82a5ac404d
2022-10-08 02:43:26 -0700 to 2022-10-25 15:14:36 -0700
- Document Half Open Range Patterns + Improve Range Patterns in General (rust-lang/reference#1274)
- clarifying which row contains the example (rust-lang/reference#1287)
- Add `sym` operands for inline assembly (rust-lang/reference#1270)
- Add basic GATs reference information (rust-lang/reference#1265)
## book
141 commits in f1e5ad844d0c61738006cdef26227beeb136948e..aa5ee485bd6bd80d205da7c82fcdd776f92fdd51
2022-09-19 09:48:21 -0400 to 2022-10-20 16:49:55 -0400
- Remove Turkish translation
- Update chapter 4 from latest print edits
- Update chapter 3 from latest print edits
- Clarify division truncates toward zero. Fixesrust-lang/book#2856.
- Update chapter 2 from latest print edits
- Fix a problem with literal style ending
- Explain both kinds of format string arguments
- Update chapter 1 from latest print edits
- Snapshot consolidated appendices
- Fix ListNumber0, newlines after lists
- Don't match nodes without anything
- Handle listing numbers in appendices too
- Regenerate everything
- Fix chapter numbers in word doc so they're in the XML
- Number Table captions too
- Handle figures too
- Regenerate ch4
- Handle listing numbers
- Regenerate ch13
- Regenerate ch12
- Regenerate ch11
- Regenerate chapter 10
- Fix ListBullet0
- Handle ending of BoxCode better
- Regenerate chapter 9
- Regenerate ch8
- Make RunInHead consistent-ish
- Fix extra newline before boxes
- Fix Box RunIn Head/Para
- Fix newline after RunInHead/Para
- Regenerate ch7
- Fix QuotePara
- Fix ListPlain
- Regenerate ch6
- Fix BoxCode
- Regenerate chapter 5
- Fix GraphicSlug and CaptionLine
- Regenerate snapshot of chapter 4
- Fix boxes a bit
- Add a shellcheck ignore
- Handle BoxListBullet
- Handle superscript
- Regenerate ch3 from xml and fix tables
- Fix italics and whitespace interactions
- Fix italic preceding/following
- Fix preceding/following xpaths again
- Fix italics
- Fix code blocks
- Fix more last bullets in lists
- Fix box newlines
- Fix last bullet in a list
- Fix BoxType
- Fix notes
- Fix literals
- Add the no editing warning at the top when getting snapshots from docx
- Make the snapshot of the frontmatter nicer
- Updates to appendixes C, D, and E after copyedit checks
- Snapshots after copyedit checks of appendices a and b + recheck of 20
- Snapshot of appendices from copyedit
- Updated snapshot of the appendices
- Re-checks of chapter 19
- Re-checks of chapter 18
- Messy snapshot of chapter 20 after copyedit checks
- Snapshot of ch20 after copyedit
- Updated snapshot of chapter 20
- Messy snapshot of chapter 19 after copyedit checks
- Snapshot of ch19 after copyedit
- Updated snapshot of ch19
- Messy snapshot of ch 18 after copyedit review
- Snapshot of ch 18 after copyedit
- Update snapshot of ch18
- Messy snapshot of ch 17 after copyedit review
- Snapshot of ch17 copyedit
- Updated snapshot of ch17
- Messy snapshot of ch16 after copyedit
- Snapshot of ch16 copyedited
- Updated snapshot of ch16
- Messy snapshot of ch 15 after copyedit checks
- Re-review of earlier chapters
- Snapshot of ch15 copyedit
- Update snapshot of ch15
- Messy snapshots of other chapters with indentation fixed
- Messy snapshot of ch2 with indentation fixed
- Add unittests to the allowed words
- Messy snapshot of chapter 14 after checking copyedit
- Snapshot of chapter 14 after copyedit
- Update snapshot of ch14
- Regenerate manual output for chapter 14
- Messy snapshot of chapter 13 after copyedit check
- Updated snapshot of ch13 after copyedit
- Updated snapshot of ch13
- Messy snapshot of chapter 12 after copyedit checks
- Snapshot of chapter 12 copyedited
- Update snapshot for chapter 12
- Messy snapshot of chapter 11 after copyedit check
- Snapshot of chapter 11 copyedited
- Updated snapshot of chapter 11
- Messy snapshot of chapter 10 after copyedit check
- Snapshot of chapter 10 copyedit
- Updated snapshot of chapter 10
- Messy snapshot of ch9 after copyedit checks
- Snapshot of ch 9 copyedit
- Update snapshot of chapter 9
- Messy snapshot of chapter 8
- Update println style in ch8
- Snapshot of chapter 8 from copyedit
- Updated snapshot of chapter 8
- Rearrange my notes yet again
- Messy snapshot of ch7 after copyedit checks
- Snapshot of chapter 7 from copyedit, fix chapter 6 name
- Update snapshot of chapter 7
- Messy snapshot of chapter 6 after copyedit check
- Update snapshot of chapter 6
- Change my notes again
- Messy snapshot of chapter 5 after checking copyedit
- Snapshot of chapter 5 from copyedit
- Messy snapshot of chapter 4 after copyedit check
- Changing my notes again
- Snapshot of ch4 from nostarch
- Messy snapshot of chapter 3 after copyedit check, ch4 on start check
- Snapshot of ch3 from nostarch
- Updated snapshot of ch3
- reorder notes
- Messy snapshot of chapter 1 after copyedit check
- Snapshot of ch01 docx from nostarch
- Updated snapshot of chapter 1
- Messy snapshot of frontmatter docx
- Another snapshot to fix the crab pinchers description
- Messy snapshot of chapter 2 docx
- Get the latest snapshot of chapter 2
- Upgrade to rand 0.8.5
- Notes to self
- Update xsl and take snapshots from docx, such as they are
- Update instructions on docx -> md now that I've done it again
- Propagate frontmatter edits to src
- Updated snapshots extracted from frontmatter
- Support different styles in the docx
- Line wrap bio
- Frontmatter from word doc
- Edits to docx files for nostarch
- docx files from nostarch
## rust-by-example
6 commits in 5e7b296d6c345addbd748f242aae28c42555c015..03491f33375c5a2a1661c7fa4be671fe95ce1249
2022-10-05 08:24:45 -0300 to 2022-10-21 07:30:08 -0300
- fixrust-lang/rust-by-example#1628: the box pointer is on stack not on heap (rust-lang/rust-by-example#1629)
- fixrust-lang/rust-by-example#1608: out-of-bound indexing is a runtime error (not a compile-time error) (rust-lang/rust-by-example#1626
)
- Fix: Path internal representation and conversions (rust-lang/rust-by-example#1625)
- fix crate name in example (rust-lang/rust-by-example#1620)
- avoid reserved keyword try as crate name (rust-lang/rust-by-example#1619)
- Fix typo in iter_result.md (rust-lang/rust-by-example#1614)
## rustc-dev-guide
7 commits in 7518c3445dc02df0d196f5f84e568d633c5141fb..51a37ad19a15709d0601afbac6581f5aea6a45da
2022-10-08 12:29:47 +0200 to 2022-10-25 10:18:58 -0700
- Update `traits/resolution.md` (rust-lang/rustc-dev-guide#1494)
- Update diagnostics to flat fluent message paths
- Update rust-analyzer suggestions (rust-lang/rustc-dev-guide#1487)
- miri is no longer a submodule but a subtree. (rust-lang/rustc-dev-guide#1488)
- fix some links (rust-lang/rustc-dev-guide#1490)
- typo and grammar (rust-lang/rustc-dev-guide#1484)
- Add missing prerequisite for some Linux distros (rust-lang/rustc-dev-guide#1481)
This patch makes it possible to use varargs for calling conventions,
which are either based on C (like efiapi) or C is based
on them (for example sysv64 and win64).
Change process spawning to inherit the parent's signal mask by default
Previously, the signal mask was always reset when a child process is
started. This breaks tools like `nohup` which expect `SIGHUP` to be
blocked for all transitive processes.
With this change, the default behavior changes to inherit the signal mask.
This also changes the signal disposition for `SIGPIPE` to only be changed if the `#[unix_sigpipe]` attribute isn't set.
Previously, the signal mask is always reset when a child process is
started. This breaks tools like `nohup` which expect `SIGHUP` to be
blocked.
With this change, the default behavior changes to inherit the signal mask.
This also changes the signal disposition for `SIGPIPE` to only be
changed if the `#[unix_sigpipe]` attribute isn't set.
Update books
## nomicon
1 commits in f53bfa056929217870a5d2df1366d2e7ba35096d..9c73283775466d22208a0b28afcab44db4c0cc10
2022-09-05 07:19:02 -0700 to 2022-09-30 07:31:22 +0900
- Fix typo (rust-lang/nomicon#380)
## reference
9 commits in a7cdac33ca7356ad49d5c2b5e2c5010889b33eee..f6ed74f582bddcec73f753eafaab3749c4f7df61
2022-09-19 17:39:58 -0700 to 2022-10-08 02:43:26 -0700
- Typo 'a' -> 'an' (rust-lang/reference#1280)
- One line one sentence for expressions and statements main chapters (rust-lang/reference#1277)
- Document let else statements (rust-lang/reference#1156)
- Document `label_break_value` in the reference (rust-lang/reference#1263)
- Document target_has_atomic (rust-lang/reference#1171)
- update 'unsafe' (rust-lang/reference#1278)
- Update tokens.md (rust-lang/reference#1276)
- One sentence, one line Patterns chapter (rust-lang/reference#1275)
- Use semver-compliant example version (rust-lang/reference#1272)
## rust-by-example
9 commits in 767a6bd9727a596d7cfdbaeee475e65b2670ea3a..5e7b296d6c345addbd748f242aae28c42555c015
2022-09-14 09:17:18 -0300 to 2022-10-05 08:24:45 -0300
- Make it clear that rustdoc uses the commonmark spec (rust-lang/rust-by-example#1622)
- Update defaults.md (rust-lang/rust-by-example#1615)
- added "see also" for the @ binding sigil (rust-lang/rust-by-example#1612)
- add more precision to the effects of --bin flag (rust-lang/rust-by-example#1607)
- create bar project in cargo/dependencies example (rust-lang/rust-by-example#1606)
- use consistent wording about type annotation (rust-lang/rust-by-example#1603)
- cast.md improvements (rust-lang/rust-by-example#1599)
- Fix typo in macros.md (rust-lang/rust-by-example#1598)
- Corrected mistaken "The" instead of "There" (rust-lang/rust-by-example#1617)
## rustc-dev-guide
2 commits in 9a86c0467bbe42056f73fdf5b03fff757d7c4a9b..7518c3445dc02df0d196f5f84e568d633c5141fb
2022-10-07 18:34:51 +0200 to 2022-10-08 12:29:47 +0200
- Update debugging.md
- Use llvm subdomain for compiler-explorer link
## embedded-book
1 commits in 4ce51cb7441a6f02b5bf9b07b2eb755c21ab7954..c533348edd69f11a8f4225d633a05d7093fddbf3
2022-09-15 08:53:09 +0000 to 2022-10-10 10:16:49 +0000
- Fix a typo in registers.md (rust-embedded/book#330)
rustdoc: Document effect of fundamental types
This was implemented in https://github.com/rust-lang/rust/pull/96565, but not documented. But it's a useful feature for everyone who implements own wrapper (especially wrappers-around-pointers) types, so that they can behave like pointers (and stdlib wrappers) do -- so here goes a mention in the unstable section of the rustdoc book.
(That is where I initially looked to find tricks for making my own wrapper types be transparent to documentation).
- .gitattributes: Mark minified javascript as binary to filter greps
- fix very minor punctuation typo
- diagnostic structs: derive on enum (#1477)
- Update running tests with the new flags (#1476)
- Rename typeck to hir_analysis (#1475)
- fix typo and make paragraph consistent (#1474)
- Update about-this-guide.md
- Link to the correct page in "about this guide"
- Update r-a config suggestions
- don't refer to the compile-time interpreter as "Miri" (#1471)
- UPDATE - Diagnostic docs to reflect renamed traits and macros in rustc PR#101558
- Update mdbook and its extensions versions
- Remove unmaintained action
- Update some actions versions
- Fix some typos
Update motivated in large part by the most recent commit, to fix `git
grep`.
The compiler currently has `-Ztime` and `-Ztime-passes`. I've used
`-Ztime-passes` for years but only recently learned about `-Ztime`.
What's the difference? Let's look at the `-Zhelp` output:
```
-Z time=val -- measure time of rustc processes (default: no)
-Z time-passes=val -- measure time of each rustc pass (default: no)
```
The `-Ztime-passes` description is clear, but the `-Ztime` one is less so.
Sounds like it measures the time for the entire process?
No. The real difference is that `-Ztime-passes` prints out info about passes,
and `-Ztime` does the same, but only for a subset of those passes. More
specifically, there is a distinction in the profiling code between a "verbose
generic activity" and an "extra verbose generic activity". `-Ztime-passes`
prints both kinds, while `-Ztime` only prints the first one. (It took me
a close reading of the source code to determine this difference.)
In practice this distinction has low value. Perhaps in the past the "extra
verbose" output was more voluminous, but now that we only print stats for a
pass if it exceeds 5ms or alters the RSS, `-Ztime-passes` is less spammy. Also,
a lot of the "extra verbose" cases are for individual lint passes, and you need
to also use `-Zno-interleave-lints` to see those anyway.
Therefore, this commit removes `-Ztime` and the associated machinery. One thing
to note is that the existing "extra verbose" activities all have an extra
string argument, so the commit adds the ability to accept an extra argument to
the "verbose" activities.
The system GCC 5 in ubuntu:16.04 will be too old to compile LLVM 16, so
we need an upgrade. To avoid raising the minimum glibc requirements for
`i586-unknown-linux-gnu`, this target is converted to a crosstool-ng
toolchain, *relaxing* it to the same Linux 3.2 / glibc 2.17 minimum we
use elsewhere. The musl targets still use Ubuntu's system toolchain, but
this doesn't have the same compatibility concerns.
Remove support for legacy PM
This removes support for optimizing with LLVM's legacy pass manager, as well as the unstable `-Znew-llvm-pass-manager` option. We have been defaulting to the new PM since LLVM 13 (except for s390x that waited for 14), and LLVM 15 removed support altogether. The only place we still use the legacy PM is for writing the output file, just like `llc` does.
cc #74705
r? ``@nikic``
Document some missing command-line arguments
The rustc command-line arguments docs should document all of the stable arguments for rustc. Two were missing, `--force-warn` which was somewhat documented in the lint-levels chapter, but should also include a mention in the arguments list. `--diagnostic-width` was stabilized in #95635, but the docs weren't updated.
Update books
## nomicon
1 commits in d880e6ac2acf133dce640da24b9fb692844f02d4..f53bfa056929217870a5d2df1366d2e7ba35096d
2022-08-24 12:42:34 -0700 to 2022-09-05 07:19:02 -0700
- Small typo (rust-lang/nomicon#379)
## reference
9 commits in f62e93c28323ed9637d0a205a0c256498674a509..a7cdac33ca7356ad49d5c2b5e2c5010889b33eee
2022-08-28 10:01:28 -0700 to 2022-09-19 17:39:58 -0700
- Clarify wording for references. (rust-lang/reference#1223)
- Update Unicode reference to match rustc implementation (rust-lang/reference#1271)
- Add documentation for raw-dylib and link_ordinal (rust-lang/reference#1244)
- Specify guarantees for repr(rust) structs (rust-lang/reference#1152)
- Classify AsyncBlockExpression as ExpressionWithoutBlock (rust-lang/reference#1268)
- Update closure-expr.md (rust-lang/reference#1269)
- Clarify that 0 is a valid multiple of a type's alignment (rust-lang/reference#1260)
- Remove `ne` from derive example (rust-lang/reference#1264)
- Clarify reference on async blocks (rust-lang/reference#1262)
## book
6 commits in 0a5421ceb238357b3634fb75234eba4d1dad643c..f1e5ad844d0c61738006cdef26227beeb136948e
2022-08-28 19:51:04 -0400 to 2022-09-19 09:48:21 -0400
- Fix punctuation in ch05-02
- Ownership move chapter link fix
- Wrong listing number
- Reword text around box
- `Box<T>` instead of "box"
- Update Clippy output in Appendix D
## rust-by-example
2 commits in 03301f8ae55fa6f20f7ea152a517598e6db2cdb7..767a6bd9727a596d7cfdbaeee475e65b2670ea3a
2022-08-14 08:51:44 -0300 to 2022-09-14 09:17:18 -0300
- struct_visibility.md: Remove unneeded '#[allow(dead_code)]' (rust-lang/rust-by-example#1609)
- Fix assorted typos (rust-lang/rust-by-example#1601)
## rustc-dev-guide
15 commits in 04892c1a6fc145602ac7367945fda9d4ee83c9fb..f587d6e7cddeaa3cf0a33ec1e368df1a408fa0aa
2022-08-29 20:07:51 +0200 to 2022-09-20 07:43:59 +0900
- Update stability guide to use CURRENT_RUSTC_VERSION (rust-lang/rustc-dev-guide#1468)
- Add a note about building `rust-analyzer-proc-macro-srv` (rust-lang/rustc-dev-guide#1467)
- Link from "implementing to new features" to mcp.md (rust-lang/rustc-dev-guide#1465)
- remove stray **
- Explain the new valtree system for type level constants. (rust-lang/rustc-dev-guide#1097)
- fix typos and formatting
- Say "bootstrap" instead of "rustbuild"; the latter is not explained anywhere and is not much more clear.
- Rewrite the section on passing flags to subcommands
- Remove the diagram of all outputs generated by x.py
- "symbol names" => ABI
- Add symbol-addition to the how-to for new features (rust-lang/rustc-dev-guide#1457)
- Fix typo (rust-lang/rustc-dev-guide#1459)
- Document multipart_suggestion derive on SessionSubdiagnostic
- Add reference for updating Windows PATH and fix typo
- Update for removal of RLS (rust-lang/rustc-dev-guide#1450)
## embedded-book
1 commits in befe6840874311635c417cf731377f07234ee373..4ce51cb7441a6f02b5bf9b07b2eb755c21ab7954
2022-07-25 07:51:14 +0000 to 2022-09-15 08:53:09 +0000
- Create CITATION.bib (as per rust-embedded/book#327) (rust-embedded/book#329)
Add armv5te-none-eabi and thumbv5te-none-eabi targets
Creates two new Tier 3 targets, `armv5te-none-eabi` and `thumbv5te-none-eabi`. They are for the same target architecture (armv5te), but one defaults to the A32 instruction set and the other defaults to T32. Based on the existing `armv4t-none-eabi` and `thumbv4t-none-eabi` targets.
My particular use case for these targets is Nintendo DS homebrew, but they should be usable for any armv5te system.
Going through the Tier 3 target policy:
> A tier 3 target must have a designated developer or developers (the "target maintainers") on record to be CCed when issues arise regarding the target. (The mechanism to track and CC such developers may evolve over time.)
That will be me.
> Targets must use naming consistent with any existing targets.
Naming is consistent with previous targets.
>> Target names should not introduce undue confusion or ambiguity unless absolutely necessary to maintain ecosystem compatibility.
No ambiguity here.
> Tier 3 targets may have unusual requirements to build or use, but must not create legal issues or impose onerous legal terms for the Rust project or for Rust developers or users.
Doesn't create any legal issues.
>> The target must not introduce license incompatibilities.
This doesn't introduce any new licenses.
>> Anything added to the Rust repository must be under the standard Rust license (MIT OR Apache-2.0).
Yep.
>> The target must not cause the Rust tools or libraries built for any other host (even when supporting cross-compilation to the target) to depend on any new dependency less permissive than the Rust licensing policy. This applies whether the dependency is a Rust crate that would require adding new license exceptions (as specified by the tidy tool in the rust-lang/rust repository), or whether the dependency is a native library or binary. In other words, the introduction of the target must not cause a user installing or running a version of Rust or the Rust tools to be subject to any new license requirements.
No new license requirements.
>> Compiling, linking, and emitting functional binaries, libraries, or other code for the target (whether hosted on the target itself or cross-compiling from another target) must not depend on proprietary (non-FOSS) libraries.
Everything this uses is FOSS, no proprietary required.
> Neither this policy nor any decisions made regarding targets shall create any binding agreement or estoppel by any party. If any member of an approving Rust team serves as one of the maintainers of a target, or has any legal or employment requirement (explicit or implicit) that might affect their decisions regarding a target, they must recuse themselves from any approval decisions regarding the target's tier status, though they may otherwise participate in discussions.
OK.
>> This requirement does not prevent part or all of this policy from being cited in an explicit contract or work agreement (e.g. to implement or maintain support for a target). This requirement exists to ensure that a developer or team responsible for reviewing and approving a target does not face any legal threats or obligations that would prevent them from freely exercising their judgment in such approval, even if such judgment involves subjective matters or goes beyond the letter of these requirements.
OK.
> Tier 3 targets should attempt to implement as much of the standard libraries as possible and appropriate (core for most targets, alloc for targets that can support dynamic memory allocation, std for targets with an operating system or equivalent layer of system-provided functionality), but may leave some code unimplemented (either unavailable or stubbed out as appropriate), whether because the target makes it impossible to implement or challenging to implement. The authors of pull requests are not obligated to avoid calling any portions of the standard library on the basis of a tier 3 target not implementing those portions.
This is a bare-metal target with only support for `core` (and `alloc`, if the user provides an allocator).
> The target must provide documentation for the Rust community explaining how to build for the target, using cross-compilation if possible. If the target supports running binaries, or running tests (even if they do not pass), the documentation must explain how to run such binaries or tests for the target, using emulation if possible or dedicated hardware if necessary.
Documentation has been added.
> Tier 3 targets must not impose burden on the authors of pull requests, or other developers in the community, to maintain the target. In particular, do not post comments (automated or manual) on a PR that derail or suggest a block on the PR based on a tier 3 target. Do not send automated messages or notifications (via any medium, including via `@)` to a PR author or others involved with a PR regarding a tier 3 target, unless they have opted into such messages.
OK.
> Backlinks such as those generated by the issue/PR tracker when linking to an issue or PR are not considered a violation of this policy, within reason. However, such messages (even on a separate repository) must not generate notifications to anyone involved with a PR who has not requested such notifications.
OK.
> Patches adding or updating tier 3 targets must not break any existing tier 2 or tier 1 target, and must not knowingly break another tier 3 target without approval of either the compiler team or the maintainers of the other tier 3 target.
This doesn't break any other targets.
>> In particular, this may come up when working on closely related targets, such as variations of the same architecture with different features. Avoid introducing unconditional uses of features that another variation of the target may not have; use conditional compilation or runtime detection, as appropriate, to let each target run code supported by that target.
No unnecessary unconditional features here.
