Move `std::io::BufRead` to `alloc::io` by bushrat011899 · Pull Request #158546 · rust-lang/rust

bushrat011899 · 2026-06-29T05:42:08Z

ACP: rust-lang/libs-team#755
Tracking issue: #154046
Split From: #156527
~~Blocked On: #158545~~

Description

Moves std::io::BufRead to alloc::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. Blocked on #158545.

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 · 2026-06-29T05:42:13Z

r? @clarfonthey

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Owners of files modified in this PR: @ChrisDenton, libs
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bushrat011899 · 2026-06-29T05:42:19Z

@rustbot blocked

clarfonthey · 2026-07-18T23:18:54Z

Seems straightforward, minus one small thing. Otherwise LGTM.

More consistent with the default functions for `Read` Co-Authored-By: Clar Fon <15850505+clarfonthey@users.noreply.github.com>

clarfonthey · 2026-07-19T03:42:13Z

@bors r+

rust-bors · 2026-07-19T03:42:16Z

📌 Commit 7c0c4ef has been approved by clarfonthey

It is now in the queue for this repository.

…clarfonthey Move `std::io::BufRead` to `alloc::io` ACP: rust-lang/libs-team#755 Tracking issue: rust-lang#154046 Split From: rust-lang#156527 ~~Blocked On: rust-lang#158545 ## Description Moves `std::io::BufRead` to `alloc::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`. Blocked on rust-lang#158545. --- ## 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 3 pull requests Successful merges: - #159188 (Always generate private and hidden items in JSON docs of the stdlib) - #158546 (Move `std::io::BufRead` to `alloc::io`) - #159372 (Remove SIZE generic param from DisplayBuffer in core::net)

…clarfonthey Move `std::io::BufRead` to `alloc::io` ACP: rust-lang/libs-team#755 Tracking issue: rust-lang#154046 Split From: rust-lang#156527 ~~Blocked On: rust-lang#158545 ## Description Moves `std::io::BufRead` to `alloc::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`. Blocked on rust-lang#158545. --- ## 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 5 pull requests Successful merges: - #158546 (Move `std::io::BufRead` to `alloc::io`) - #159372 (Remove SIZE generic param from DisplayBuffer in core::net) - #159548 (miri subtree update) - #159508 (Some cleanup in `rustc_attr_parsing`) - #159539 ([rustc_abi] Customize `Debug` for `Primitive` and `Scalar`)

Rollup merge of #158546 - bushrat011899:alloc_io_bufread, r=clarfonthey Move `std::io::BufRead` to `alloc::io` ACP: rust-lang/libs-team#755 Tracking issue: #154046 Split From: #156527 ~~Blocked On: #158545 ## Description Moves `std::io::BufRead` to `alloc::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`. Blocked on #158545. --- ## 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.

…=clarfonthey Move `std::io::buffered` to `alloc::io` ACP: rust-lang/libs-team#755 Tracking issue: rust-lang#154046 Split From: rust-lang#156527 ~~Blocked On: rust-lang#158546 ## Description Moves `std::io::BufReader`/`BufWriter`/`LineWriter`/etc. to `alloc::io`. This is effectively a direct cut and paste. Blocked on rust-lang#158546. --- ## 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 merge of #158547 - bushrat011899:alloc_io_buffered, r=clarfonthey Move `std::io::buffered` to `alloc::io` ACP: rust-lang/libs-team#755 Tracking issue: #154046 Split From: #156527 ~~Blocked On: #158546 ## Description Moves `std::io::BufReader`/`BufWriter`/`LineWriter`/etc. to `alloc::io`. This is effectively a direct cut and paste. Blocked on #158546. --- ## 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.

Rollup of 5 pull requests Successful merges: - rust-lang/rust#158546 (Move `std::io::BufRead` to `alloc::io`) - rust-lang/rust#159372 (Remove SIZE generic param from DisplayBuffer in core::net) - rust-lang/rust#159548 (miri subtree update) - rust-lang/rust#159508 (Some cleanup in `rustc_attr_parsing`) - rust-lang/rust#159539 ([rustc_abi] Customize `Debug` for `Primitive` and `Scalar`)

Move `std::io::buffered` to `alloc::io` ACP: rust-lang/libs-team#755 Tracking issue: rust-lang/rust#154046 Split From: rust-lang/rust#156527 ~~Blocked On: rust-lang/rust#158546 ## Description Moves `std::io::BufReader`/`BufWriter`/`LineWriter`/etc. to `alloc::io`. This is effectively a direct cut and paste. Blocked on rust-lang/rust#158546. --- ## Notes * No AI tooling of any kind was used during the creation of this PR. * Please see rust-lang/rust#154046 (comment) for a review order and broader context for this PR.

…nia-e Fix swapped documentation lines on `io::Read` While reading the documentation for the `std::io::Read` trait, I noticed some wording out of order: > Please note that each call to [read()](https://doc.rust-lang.org/nightly/std/io/trait.Read.html#method.read) may involve a system call, and BufReader, will be more efficient. therefore, using something that implements [BufRead](https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html), such as It looks like rust-lang#158546 accidentally swapped two lines when inserting an intra-doc link; this PR swaps them back.

Rollup merge of #160836 - Jontos:fix-read-doc-line-order, r=nia-e Fix swapped documentation lines on `io::Read` While reading the documentation for the `std::io::Read` trait, I noticed some wording out of order: > Please note that each call to [read()](https://doc.rust-lang.org/nightly/std/io/trait.Read.html#method.read) may involve a system call, and BufReader, will be more efficient. therefore, using something that implements [BufRead](https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html), such as It looks like #158546 accidentally swapped two lines when inserting an intra-doc link; this PR swaps them back.

Fix swapped documentation lines on `io::Read` While reading the documentation for the `std::io::Read` trait, I noticed some wording out of order: > Please note that each call to [read()](https://doc.rust-lang.org/nightly/std/io/trait.Read.html#method.read) may involve a system call, and BufReader, will be more efficient. therefore, using something that implements [BufRead](https://doc.rust-lang.org/nightly/std/io/trait.BufRead.html), such as It looks like rust-lang/rust#158546 accidentally swapped two lines when inserting an intra-doc link; this PR swaps them back.

rustbot assigned clarfonthey Jun 29, 2026

rustbot added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label 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

This was referenced Jun 29, 2026

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

Open

Move std::io::buffered to alloc::io #158547

Merged