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

…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.

…uwer Rollup of 21 pull requests Successful merges: - #150946 (intrinsics: Add a fallback for non-const libm float functions) - #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) - #156508 (Infer all anonymous lifetimes in assoc consts as `'static`) - #158617 (allow mGCA const arguments to fall back to anon consts) - #158645 (Fix splat ICEs and ban it in closures) - #158859 (Improve `-Zls` diagnostic message on `.rs` files) - #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) - #158940 (Implement feature `char_to_u32`) - #158951 (Merge three `MaxUniverse`s into one) - #158961 (Reapply "LLVM 23: Run AssignGUIDPass in some places") - #158996 ([compiler] Implement `PartialOrd` via `Ord` for `Span` and newtype_indexes) - #159005 (Use `as_lang_item` instead of repeatedly matching)

…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 24 pull requests Successful merges: - #150946 (intrinsics: Add a fallback for non-const libm float functions) - #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`) - #156027 (Consider captured regions for opaque type region liveness.) - #156370 (Reject linked dylib EII default overrides) - #156508 (Infer all anonymous lifetimes in assoc consts as `'static`) - #157561 (rustdoc: do not include extra stuff in span) - #158617 (allow mGCA const arguments to fall back to anon consts) - #158645 (Fix splat ICEs and ban it in closures) - #158859 (Improve `-Zls` diagnostic message on `.rs` files) - #158988 (Redo `TokenStreamIter`) - #158347 (Improve generic parameters handling for #[diagnostic::on_const]) - #158384 (Allow BackwardIncompatibleDropHint in polonius legacy) - #158722 (delegation: do not always inherit `ConstArgHasType` predicates) - #158739 (view-types: HIR lowering) - #158877 (borrowck: Keep returned `path` from `best_blame_constraint()` consistent) - #158883 (tests: fix enum-match.rs to handle LLVM 23) - #158886 (Add documentation for the `no_std` attribute) - #158940 (Implement feature `char_to_u32`) - #158951 (Merge three `MaxUniverse`s into one) - #158961 (Reapply "LLVM 23: Run AssignGUIDPass in some places") - #158995 (Use REST API in linkchecker script) - #158996 ([compiler] Implement `PartialOrd` via `Ord` for `Span` and newtype_indexes)

…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 24 pull requests Successful merges: - #150946 (intrinsics: Add a fallback for non-const libm float functions) - #158541 (Move `std::io::Write` to `core::io`) - #156027 (Consider captured regions for opaque type region liveness.) - #156370 (Reject linked dylib EII default overrides) - #156508 (Infer all anonymous lifetimes in assoc consts as `'static`) - #157561 (rustdoc: do not include extra stuff in span) - #158617 (allow mGCA const arguments to fall back to anon consts) - #158645 (Fix splat ICEs and ban it in closures) - #158859 (Improve `-Zls` diagnostic message on `.rs` files) - #158988 (Redo `TokenStreamIter`) - #158347 (Improve generic parameters handling for #[diagnostic::on_const]) - #158384 (Allow BackwardIncompatibleDropHint in polonius legacy) - #158722 (delegation: do not always inherit `ConstArgHasType` predicates) - #158739 (view-types: HIR lowering) - #158877 (borrowck: Keep returned `path` from `best_blame_constraint()` consistent) - #158883 (tests: fix enum-match.rs to handle LLVM 23) - #158886 (Add documentation for the `no_std` attribute) - #158940 (Implement feature `char_to_u32`) - #158951 (Merge three `MaxUniverse`s into one) - #158960 (Fix bootstrap submodule path prefix matching) - #158961 (Reapply "LLVM 23: Run AssignGUIDPass in some places") - #158995 (Use REST API in linkchecker script) - #158996 ([compiler] Implement `PartialOrd` via `Ord` for `Span` and newtype_indexes) - #159036 (bootstrap: expand '@argfile' arguments to rustc shim)

Rollup merge of #158541 - bushrat011899:core_io_write, r=clarfonthey Move `std::io::Write` to `core::io` 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 #154046 (comment) for a review order and broader context for this PR.

JonathanBrouwer · 2026-07-12T07:42:45Z

@rust-timer build 0ffdcdb

rust-timer · 2026-07-12T07:42:48Z

Missing artifact for sha 0ffdcdb2b658591abfb86086a931c3cb8227c0ce (https://ci-artifacts.rust-lang.org/rustc-builds/0ffdcdb2b658591abfb86086a931c3cb8227c0ce/rustc-nightly-x86_64-unknown-linux-gnu.tar.xz); not built yet, try again later.

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

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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

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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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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

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

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Rollup of 12 pull requests #158963

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Rollup of 14 pull requests #158971

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Rollup of 25 pull requests #158986

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Rollup of 17 pull requests #159007

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Move `std::io::Write` to `core::io`#158541

Move `std::io::Write` to `core::io`#158541
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