Add BE8 support

[WorksButNotTested]

Built using the following /config.toml

changelog-seen = 2

[llvm]
download-ci-llvm = false
skip-rebuild = true
optimize = true
ninja = true
targets = "ARM;X86"
clang = false

[build]
target = ["x86_64-unknown-linux-gnu", "armeb-linux-gnueabi"]
docs = false
docs-minification = false
compiler-docs = false
[install]
prefix = "/home/user/x-tools/rust/"

[rust]
debug-logging=true
backtrace = true
incremental = true

[target.x86_64-unknown-linux-gnu]

[dist]

[target.armeb-linux-gnueabi]
cc = "/home/user/x-tools/armeb-linux-gnueabi/bin/armeb-linux-gnueabi-gcc"
cxx = "/home/user/x-tools/armeb-linux-gnueabi/bin/armeb-linux-gnueabi-g++"
ar = "/home/user/x-tools/armeb-linux-gnueabi/bin/armeb-linux-gnueabi-ar"
ranlib = "/home/user/x-tools/armeb-linux-gnueabi/bin/armeb-linux-gnueabi-ranlib"
linker = "/home/user/x-tools/armeb-linux-gnueabi/bin/armeb-linux-gnueabi-gcc"
llvm-config = "/home/user/x-tools/clang/bin/llvm-config"
llvm-filecheck = "/home/user/x-tools/clang/bin/FileCheck"

The following .cargo/config is needed inside any project directory:

[build]
target = "armeb-linux-gnueabi"

[target.armeb-linux-gnueabi]
linker = "armeb-linux-gnueabi-gcc"

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @jackh726 (or someone else) soon.

Please see the contribution instructions for more information.

[rust-highfive]

⚠️ Warning ⚠️

• These commits modify compiler targets. (See the Target Tier Policy.)

[jackh726]

Just going to reroll this - I'd rather try to get someone who can review this more promptly.

r? compiler

[WorksButNotTested]

Just going to reroll this - I'd rather try to get someone who can review this more promptly.

r? compiler

I’m not precious about my commit. Just needed to add BE8 support as a feature. It’s working for me, but I’m not so familiar with the internals of rust to say I’ve gone about it in the right way. If anyone has a different or better way of doing it, then that’s just fine with me. Just wanted to make the PR to get some feedback.

[wesleywiser]

Hi @WorksButNotTested, thanks for the PR!

There's a few things you'll need to do before we can merge this:

• Please add an entry to the Tier 3 section in this document for the target src/doc/rustc/src/platform-support.md.
• We're also asking people to add a page to the platform-support directory in the same folder. You can find look at some of the other pages in that folder as an example (for instance src/doc/rustc/src/platform-support/wasm64-unknown-unknown.md).
• Finally, please quote the corresponding requirements verbatim from the tier 3 target tier policy to explain how the target meets those requirements (leaving a new comment here is fine). You can find an example of this in the PR description for Add SOLID targets #86191.

Thank you!

[WorksButNotTested]

Tier 3 target policy

At this tier, the Rust project provides no official support for a target, so we
place minimal requirements on the introduction of targets.

A proposed new tier 3 target must be reviewed and approved by a member of the
compiler team based on these requirements. The reviewer may choose to gauge
broader compiler team consensus via a [Major Change Proposal (MCP)][MCP].

A proposed target or target-specific patch that substantially changes code
shared with other targets (not just target-specific code) must be reviewed and
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• A tier 3 target must have a designated developer or developers (the "target
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  @WorksButNotTested

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  The target name follows the naming conventions adopted by the GNU toolchain, namely
  the host triplet architecture-<vendor>-host-abi. The vendor portion of this is optional
  and irrelevant in this case and hence omitted

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[WorksButNotTested]

Hi @WorksButNotTested, thanks for the PR!

There's a few things you'll need to do before we can merge this:

* Please add an entry to the Tier 3 section in this document for the target [`src/doc/rustc/src/platform-support.md`](https://github.com/rust-lang/rust/blob/master/src/doc/rustc/src/platform-support.md).

* We're also asking people to add a page to the `platform-support` directory in the same folder. You can find look at some of the other pages in that folder as an example (for instance [`src/doc/rustc/src/platform-support/wasm64-unknown-unknown.md`](https://github.com/rust-lang/rust/blob/master/src/doc/rustc/src/platform-support/wasm64-unknown-unknown.md)).

* Finally, please quote the corresponding requirements verbatim from the [tier 3 target tier policy](https://doc.rust-lang.org/nightly/rustc/target-tier-policy.html#tier-3-target-policy) to explain how the target meets those requirements (leaving a new comment here is fine). You can find an example of this in the PR description for [Add SOLID targets #86191](https://github.com/rust-lang/rust/pull/86191).

Thank you!

Thanks for the feedback. Hopefully the above is OK for the target policy? As you will see, it is pretty similar to the normal ARM little endian target definition, but with a few tiny changes. So I hope it won't introduce any problems. I have also added some docs as requested. Please let me know what you think.

[wesleywiser]

Yep, that looks good!

The link checker is still reporting broken links. I think you might need to update src/doc/rustc/src/SUMMARY.md to include the new file as well.

[wesleywiser]

The target name follows the naming conventions adopted by the GNU toolchain, namely
the host triplet architecture--host-abi. The vendor portion of this is optional
and irrelevant in this case and hence omitted

I noticed most of our other similar targets include the unknown vendor portion. How would you feel about including that for consistency with the other existing target names?

[WorksButNotTested]

Yep, that looks good!

The link checker is still reporting broken links. I think you might need to update src/doc/rustc/src/SUMMARY.md to include the new file as well.

I think the link is working ok in the .md file, but is not working for generated HTML docs? Any idea what I’ve done wrong?

Thanks, I’ll take a look at the SUMMARY.md.

[WorksButNotTested]

The target name follows the naming conventions adopted by the GNU toolchain, namely
the host triplet architecture--host-abi. The vendor portion of this is optional
and irrelevant in this case and hence omitted

I noticed most of our other similar targets include the unknown vendor portion. How would you feel about including that for consistency with the other existing target names?

I can add that if you’d prefer. Not a problem. I think “unknown” is used as a default by GCC when the user doesn’t provide a vendor string and doesn’t reconfigure the triplet.

[wesleywiser]

I can add that if you’d prefer. Not a problem. I think “unknown” is used as a default by GCC when the user doesn’t provide a vendor string and doesn’t reconfigure the triplet.

Yeah, let's go ahead and do that then. In the absence of a compelling reason not to, I think going with the existing convention for the related targets is important. Thanks!

[WorksButNotTested]

Does this look better?

[wesleywiser]

Looks great! Thanks for the PR @WorksButNotTested 🙂

@bors r+ rollup

[bors]

📌 Commit 73d6dd5 has been approved by wesleywiser

It is now in the queue for this repository.

[WorksButNotTested]

Looks great! Thanks for the PR @WorksButNotTested 🙂

@bors r+ rollup

No worries. Thanks for the feedback.

[WorksButNotTested]

Obviously I don't expect my little PR to influence your release schedule, but do you know if it will be incorporated into 1.64? I read that is to be released on 22/09 is that right?

[wesleywiser]

We use a 3 release system: stable, beta and nightly. This just landed in nightly (or, more precisely, it should be included in tonight's nightly release) so the next time a stable release happens (on September 22), the nightly release will be promoted to beta and then in 6 weeks the beta will be promoted to stable. rustbot tagged this with 1.65.0 so it will be included in that release on November 3.

[WorksButNotTested]

Awesome. Thanks for explaining for me. Just so I know when I can retire my downstream patches.