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

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The target name ( armv6k-nintendo-3ds) reflects both CPU, vendor and model of device targeted. It is also coherent with the Rust targets' naming conventions (CPU/instruction set - vendor - model). The OS is inherent to the device model as it's built into the device ROM and only works on that exact set of hardware.

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I understand.

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Though std support isn't yet available (in any capacity), both core and alloc are supported already for this target and there isn't any "offlimit" code for other contributors to use.

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Tests aren't possible in any capacity, but (with the cited devkitARM toolchain installed properly on the host system), cross-compilation is the same as any other no-std target, requiring the unstable feature build-std with the core and alloc crates activated.

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I understand and, as already said, will provide support in case of issues with the target as long as I can.

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@rustbot label: +A-target-specs

r? @nagisa

Though std support isn't yet available (in any capacity), both core and alloc are supported already for this target and there isn't any "offlimit" code for other contributors to use.

Is std planned to be supported in any way? Just curious.

LGTM r=me pending resolution to the comments inline.

Is std planned to be supported in any way? Just curious.

The Nintendo 3DS has had multiple out-of-tree projects porting parts or all of the standard library. The 3DS is a system not very powerful, but with many features, and supports most of what would be the normal std for unix systems. Though the work can't be directly pushed over as libc requires a new dependency (a platform specific library with OS functions called libctru), so work on that must be finalized before any work on the standard. It's not my main objective to get the standard working (especially for the big requirement in maintenance that it would take, and I'm currently alone in this). Maybe after getting libc sorted out I might try to implement std support in the most thin way possible, to ensure it lasting in the future. It would be great for supporting non-platform-specific crates, but it's not a necessity.

@bors r+

📌 Commit e07ae3c has been approved by nagisa

⌛ Testing commit e07ae3c with merge 61a1029...

☀️ Test successful - checks-actions
Approved by: nagisa
Pushing 61a1029 to master...

Finished benchmarking commit (61a1029): comparison url.

Summary: This benchmark run did not return any relevant changes.

If you disagree with this performance assessment, please file an issue in rust-lang/rustc-perf.

@rustbot label: -perf-regression

Is std planned to be supported in any way? Just curious.

The Nintendo 3DS has had multiple out-of-tree projects porting parts or all of the standard library. The 3DS is a system not very powerful, but with many features, and supports most of what would be the normal std for unix systems. Though the work can't be directly pushed over as libc requires a new dependency (a platform specific library with OS functions called libctru), so work on that must be finalized before any work on the standard. It's not my main objective to get the standard working (especially for the big requirement in maintenance that it would take, and I'm currently alone in this). Maybe after getting libc sorted out I might try to implement std support in the most thin way possible, to ensure it lasting in the future. It would be great for supporting non-platform-specific crates, but it's not a necessity.

@nagisa @Meziu Just a quick note: if anyone starts work on any bindings to library functions - some companies consider the interfaces to any of their libraries a trade secret and under NDA (even if they are standard interfaces!) and console vendors are a particular case there.

This is a grey area we definitely should not move in. Please note that even if we use one of the open SDKs, this grey area still exists, because the interpretation is up to the vendor. For SDKs, thats just an area they are deliberately in, but for the libc crate, there's the problem that all platforms share one space, so also the set of problems. If there's a move to add further target support to libc, as annoying as it is, please get some legal review. Just to be clear: this is not to annoy y'all, but to make sure there's no frustration and annoyance in the future.

It'd be nice to put a note to that effect into https://github.com/rust-lang/rust/tree/master/src/doc/rustc/src/platform-support for this target, I think.

I'm a little surprised to not see a doc created there with at least the listing of target maintainers - @nagisa I think it would be good to add those when we add targets, even if they start out mostly empty.

Is std planned to be supported in any way? Just curious.

The Nintendo 3DS has had multiple out-of-tree projects porting parts or all of the standard library. The 3DS is a system not very powerful, but with many features, and supports most of what would be the normal std for unix systems. Though the work can't be directly pushed over as libc requires a new dependency (a platform specific library with OS functions called libctru), so work on that must be finalized before any work on the standard. It's not my main objective to get the standard working (especially for the big requirement in maintenance that it would take, and I'm currently alone in this). Maybe after getting libc sorted out I might try to implement std support in the most thin way possible, to ensure it lasting in the future. It would be great for supporting non-platform-specific crates, but it's not a necessity.

@nagisa @Meziu Just a quick note: if anyone starts work on any bindings to library functions - some companies consider the interfaces to any of their libraries a trade secret and under NDA (even if they are standard interfaces!) and console vendors are a particular case there.

This is a grey area we definitely should not move in. Please note that even if we use one of the open SDKs, this grey area still exists, because the interpretation is up to the vendor. For SDKs, thats just an area they are deliberately in, but for the libc crate, there's the problem that all platforms share one space, so also the set of problems. If there's a move to add further target support to libc, as annoying as it is, please get some legal review. Just to be clear: this is not to annoy y'all, but to make sure there's no frustration and annoyance in the future.

I understand exactly what you mean. I’ve never heard of any problems regarding the use of open SDKs (especially for what is now an out-of-production console) but it’s true that doesn’t exclude problems in the future, especially when dealing with the Rust project as a whole. I will think about what actions to take when implementing libc, and will consult legal advice before doing so.