Move `std::io::Write` to `core::io` by bushrat011899 · Pull Request #158541 · rust-lang/rust

bushrat011899 · 2026-06-29T04:46:53Z

ACP: rust-lang/libs-team#755
Tracking issue: #154046
Split From: #156527
~~Blocked On: #158537~~
~~Blocked On: #158540~~

Description

Moves std::io::Write to core::io. This is effectively a direct cut and paste, but with a large diff due to how many implementations need to be moved into alloc and core. Blocked on #158537 and #158540.

Notes

No AI tooling of any kind was used during the creation of this PR.
Please see Tracking Issue for alloc::io and core::io #154046 (comment) for a review order and broader context for this PR.

rustbot · 2026-06-29T04:46:58Z

r? @Darksonn

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bushrat011899 · 2026-06-29T04:47:03Z

@rustbot blocked

bushrat011899 · 2026-07-06T21:55:36Z

@rustbot ready
@clarfonthey This is the next PR in my chain if you're interested in reviewing this one too! I'm not assigning you just in case you don't want to take it on.

clarfonthey · 2026-07-07T01:02:04Z

r? clarfonthey

rustbot · 2026-07-08T08:38:54Z

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

bushrat011899 · 2026-07-08T09:16:47Z

@rustbot ready

A handful of pub(crate) functions that were previously always used in std become conditionally used once Read/Write/etc. are moved to core/alloc. I've marked those functions as #[allow(unused_imports)] to avoid changing the various callsites or adding a brittle cfg(...) to their reexport.

bushrat011899 · 2026-07-08T09:20:07Z

auto - dist-various-2 was the CI task that failed during the merge. So it might be worth a "bors try dist-various-2"?

clarfonthey · 2026-07-08T14:11:39Z

@bors try jobs=dist-various-2

Move `std::io::Write` to `core::io` try-job: dist-various-2

rust-bors · 2026-07-08T15:06:49Z

☀️ Try build successful (CI)
Build commit: f09a32d (f09a32d2764485e529832b5fd3cb8c1d59e99bd9)
Base parent: c290daa (c290daa1e5274a52e54a0f49e31bd70192abc606)

clarfonthey · 2026-07-08T15:14:50Z

@bors r+ rollup=iffy

For previous reasons of modifying a lot of I/O code and also having failed once, despite passing try now.

rust-bors · 2026-07-08T15:14:53Z

📌 Commit cb09bff has been approved by clarfonthey

It is now in the queue for this repository.

…rfonthey Move `std::io::Write` to `core::io` ACP: rust-lang/libs-team#755 Tracking issue: rust-lang#154046 Split From: rust-lang#156527 ~~Blocked On: rust-lang#158537 ~~Blocked On: rust-lang#158540 ## Description Moves `std::io::Write` to `core::io`. This is effectively a direct cut and paste, but with a large diff due to how many implementations need to be moved into `alloc` and `core`. Blocked on rust-lang#158537 and rust-lang#158540. --- ## Notes * No AI tooling of any kind was used during the creation of this PR. * Please see rust-lang#154046 (comment) for a review order and broader context for this PR.

Rollup of 25 pull requests Successful merges: - #158871 (add relnotes for 1.97.0) - #158968 (stdarch subtree update) - #157690 (codegen_ssa: pack small const aggregates into immediate stores) - #158541 (Move `std::io::Write` to `core::io`) - #154445 (rustdoc: Represent `--output-format=json` coverage and ir differently) - #156370 (Reject linked dylib EII default overrides) - #157153 (allow `Allocator`s to be used as `#[global_allocator]`s) - #158495 (Rename HAS_CT_PROJECTION to HAS_CONST_ALIAS) - #158617 (allow mGCA const arguments to fall back to anon consts) - #158645 (Fix splat ICEs and ban it in closures) - #158655 (Fix coroutine MIR saved local remapping) - #158666 (Carry the `b_offset` inside `BackendRepr::ScalarPair`) - #158870 (std: merge the unix-like io::error modules into one file) - #158920 (Update wasm-component-ld to 0.5.26) - #158926 (wrapping_sh* methods: clarify underspecified reference) - #158927 (add core test run with `-Zforce-intrinsic-fallback`) - #158932 (Do not build the compiler when invoking `x perf compare`) - #158937 (Emit the emscripten entry point as `__main_argc_argv`) - #151379 (Stabilize `VecDeque::retain_back` from `truncate_front`) - #156144 (Better docs for PartialEq (includes macro rename)) - #156548 ( Library support for aarch64-unknown-linux-pauthtest target) - #158307 (CI job for parallel frontend ui tests) - #158347 (Improve generic parameters handling for #[diagnostic::on_const]) - #158722 (delegation: do not always inherit `ConstArgHasType` predicates) - #158741 (Simplify `Option::into_flat_iter` signature)

…rfonthey Move `std::io::Write` to `core::io` ACP: rust-lang/libs-team#755 Tracking issue: rust-lang#154046 Split From: rust-lang#156527 ~~Blocked On: rust-lang#158537 ~~Blocked On: rust-lang#158540 ## Description Moves `std::io::Write` to `core::io`. This is effectively a direct cut and paste, but with a large diff due to how many implementations need to be moved into `alloc` and `core`. Blocked on rust-lang#158537 and rust-lang#158540. --- ## Notes * No AI tooling of any kind was used during the creation of this PR. * Please see rust-lang#154046 (comment) for a review order and broader context for this PR.

…uwer Rollup of 17 pull requests Successful merges: - #158510 (Enable `static_position_independent_executables` on all gnu and musl targets) - #158541 (Move `std::io::Write` to `core::io`) - #158899 (Fix `unaligned_volatile_store` by removing `MemFlags::UNALIGNED`) - #155429 (Support `u128`/`i128` c-variadic arguments) - #156370 (Reject linked dylib EII default overrides) - #157153 (allow `Allocator`s to be used as `#[global_allocator]`s) - #158535 (Support `#[track_caller]` on EII declarations) - #158617 (allow mGCA const arguments to fall back to anon consts) - #158645 (Fix splat ICEs and ban it in closures) - #158988 (Redo `TokenStreamIter`) - #158347 (Improve generic parameters handling for #[diagnostic::on_const]) - #158722 (delegation: do not always inherit `ConstArgHasType` predicates) - #158739 (view-types: HIR lowering) - #158883 (tests: fix enum-match.rs to handle LLVM 23) - #158886 (Add documentation for the `no_std` attribute) - #158951 (Merge three `MaxUniverse`s into one) - #158961 (Reapply "LLVM 23: Run AssignGUIDPass in some places")

…rfonthey Move `std::io::Write` to `core::io` ACP: rust-lang/libs-team#755 Tracking issue: rust-lang#154046 Split From: rust-lang#156527 ~~Blocked On: rust-lang#158537 ~~Blocked On: rust-lang#158540 ## Description Moves `std::io::Write` to `core::io`. This is effectively a direct cut and paste, but with a large diff due to how many implementations need to be moved into `alloc` and `core`. Blocked on rust-lang#158537 and rust-lang#158540. --- ## Notes * No AI tooling of any kind was used during the creation of this PR. * Please see rust-lang#154046 (comment) for a review order and broader context for this PR.

rustbot assigned Darksonn Jun 29, 2026

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. T-libs Relevant to the library team, which will review and decide on the PR/issue. labels Jun 29, 2026

rustbot added S-blocked Status: Blocked on something else such as an RFC or other implementation work. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Jun 29, 2026

bushrat011899 mentioned this pull request Jun 29, 2026

Tracking Issue for alloc::io and core::io #154046

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bushrat011899 force-pushed the core_io_write branch from 22e4295 to 802f7d5 Compare June 29, 2026 05:09

bushrat011899 mentioned this pull request Jun 29, 2026

Move std::io::Read to alloc::io #158544

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clarfonthey mentioned this pull request Jul 2, 2026

Add std::io::cursor::WriteThroughCursor #158537

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bushrat011899 force-pushed the core_io_write branch 2 times, most recently from ec21a69 to c806329 Compare July 3, 2026 01:49

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bushrat011899 force-pushed the core_io_write branch from c806329 to a4969f5 Compare July 6, 2026 09:35

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bushrat011899 force-pushed the core_io_write branch from a4969f5 to 9dc5fd5 Compare July 6, 2026 21:54

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rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-blocked Status: Blocked on something else such as an RFC or other implementation work. labels Jul 6, 2026

rustbot assigned clarfonthey and unassigned Darksonn Jul 7, 2026

clarfonthey reviewed Jul 7, 2026

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Comment thread library/core/src/io/write.rs

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Comment thread library/core/src/io/cursor.rs Outdated

bushrat011899 requested a review from clarfonthey July 7, 2026 01:25

clarfonthey reviewed Jul 7, 2026

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Comment thread library/alloc/src/io/impls.rs Outdated

bushrat011899 force-pushed the core_io_write branch from 65f6190 to cb09bff Compare July 8, 2026 08:38

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rust-bors Bot pushed a commit that referenced this pull request Jul 8, 2026

Auto merge of #158541 - bushrat011899:core_io_write, r=<try>

f09a32d

Move `std::io::Write` to `core::io` try-job: dist-various-2

rust-bors Bot added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Jul 8, 2026

JonathanBrouwer mentioned this pull request Jul 8, 2026

Rollup of 12 pull requests #158963

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Rollup of 14 pull requests #158971

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jhpratt mentioned this pull request Jul 8, 2026

Rollup of 25 pull requests #158986

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Rollup of 17 pull requests #159007

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Rollup of 18 pull requests #159013

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Rollup of 21 pull requests #159020

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Rollup of 21 pull requests #159024

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