Don't try to skip anything in `Skip::advance_by(0)` by cuviper · Pull Request #164488 · rust-lang/rust

cuviper · 2026-10-17T19:47:48Z

If we try to eagerly process our skip count, we might see the end of the
inner iterator. Iterator::advance_by is supposed to return a non-zero
Err count when exhausted, but there's no room for Skip to report
anything in this case. So, it's better that we don't even try.

Fixes #164480

If we try to eagerly process our skip count, we might see the end of the inner iterator. `Iterator::advance_by` is supposed to return a non-zero `Err` count when exhausted, but there's no room for `Skip` to report anything in this case. So, it's better that we don't even try.

rustbot · 2026-10-17T19:47:53Z

r? @JohnTitor

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Looks good, @bors r+

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rust-bors · 2026-10-20T10:59:03Z

📌 Commit 142d509 has been approved by JohnTitor

It is now in the queue for this repository.

Don't try to skip anything in `Skip::advance_by(0)` If we try to eagerly process our skip count, we might see the end of the inner iterator. `Iterator::advance_by` is supposed to return a non-zero `Err` count when exhausted, but there's no room for `Skip` to report anything in this case. So, it's better that we don't even try. Fixes rust-lang#164480

…uwer Rollup of 6 pull requests Successful merges: - #163104 ([debuginfo] Emit `usize` and `isize` as typedefs) - #164488 (Don't try to skip anything in `Skip::advance_by(0)`) - #164578 (Don't ignore unknown LLVM diagnostics) - #164611 (Improve bit permutation codegen) - #162668 (document that `!` does bitwise and logical negation) - #164264 (lint: suggest `fXX::is_nan` for unsuffixed NaN comparisons)

Don't try to skip anything in `Skip::advance_by(0)` If we try to eagerly process our skip count, we might see the end of the inner iterator. `Iterator::advance_by` is supposed to return a non-zero `Err` count when exhausted, but there's no room for `Skip` to report anything in this case. So, it's better that we don't even try. Fixes rust-lang#164480

…uwer Rollup of 14 pull requests Successful merges: - #163575 (core: Add examples and assembly tests for `abort_immediate`) - #163664 (Add new `RUSTC_BOOTSTRAP=-allow-unstable-compiler-flags` mode for testing stable compiler behavior in UI tests) - #163104 ([debuginfo] Emit `usize` and `isize` as typedefs) - #163338 (MIR move elimination [4/6]: MoveElimination) - #163701 (add ReadDir::dir to get the directory handle of the underlying directory) - #164488 (Don't try to skip anything in `Skip::advance_by(0)`) - #164578 (Don't ignore unknown LLVM diagnostics) - #164611 (Improve bit permutation codegen) - #164612 (std: Combine `is_powerpc64_feature_detected` into `is_powerpc_feature_detected`) - #162668 (document that `!` does bitwise and logical negation) - #164264 (lint: suggest `fXX::is_nan` for unsuffixed NaN comparisons) - #164509 (layout invariant: turn delayed bug back into proper assertion) - #164594 (rustdoc: Correctly handle inner `deprecated` attribute on modules) - #164629 (arch::breakpoint: avoid confusing 'equivalent' terminology)

Don't try to skip anything in `Skip::advance_by(0)` If we try to eagerly process our skip count, we might see the end of the inner iterator. `Iterator::advance_by` is supposed to return a non-zero `Err` count when exhausted, but there's no room for `Skip` to report anything in this case. So, it's better that we don't even try. Fixes rust-lang#164480

…uwer Rollup of 13 pull requests Successful merges: - #163664 (Add new `RUSTC_BOOTSTRAP=-allow-unstable-compiler-flags` mode for testing stable compiler behavior in UI tests) - #163104 ([debuginfo] Emit `usize` and `isize` as typedefs) - #163338 (MIR move elimination [4/6]: MoveElimination) - #163701 (add ReadDir::dir to get the directory handle of the underlying directory) - #164488 (Don't try to skip anything in `Skip::advance_by(0)`) - #164578 (Don't ignore unknown LLVM diagnostics) - #164611 (Improve bit permutation codegen) - #164612 (std: Combine `is_powerpc64_feature_detected` into `is_powerpc_feature_detected`) - #162668 (document that `!` does bitwise and logical negation) - #164264 (lint: suggest `fXX::is_nan` for unsuffixed NaN comparisons) - #164509 (layout invariant: turn delayed bug back into proper assertion) - #164594 (rustdoc: Correctly handle inner `deprecated` attribute on modules) - #164629 (arch::breakpoint: avoid confusing 'equivalent' terminology)

Don't try to skip anything in `Skip::advance_by(0)` If we try to eagerly process our skip count, we might see the end of the inner iterator. `Iterator::advance_by` is supposed to return a non-zero `Err` count when exhausted, but there's no room for `Skip` to report anything in this case. So, it's better that we don't even try. Fixes rust-lang#164480

…uwer Rollup of 15 pull requests Successful merges: - #163664 (Add new `RUSTC_BOOTSTRAP=-allow-unstable-compiler-flags` mode for testing stable compiler behavior in UI tests) - #163104 ([debuginfo] Emit `usize` and `isize` as typedefs) - #163338 (MIR move elimination [4/6]: MoveElimination) - #163701 (add ReadDir::dir to get the directory handle of the underlying directory) - #164488 (Don't try to skip anything in `Skip::advance_by(0)`) - #164611 (Improve bit permutation codegen) - #164612 (std: Combine `is_powerpc64_feature_detected` into `is_powerpc_feature_detected`) - #148842 (Avoid incorrect lifetime suggestion involving `sym::anon`) - #162668 (document that `!` does bitwise and logical negation) - #164264 (lint: suggest `fXX::is_nan` for unsuffixed NaN comparisons) - #164509 (layout invariant: turn delayed bug back into proper assertion) - #164540 (Minor optimizations around macro parsing) - #164594 (rustdoc: Correctly handle inner `deprecated` attribute on modules) - #164595 (Allow attributes in function trait parameters) - #164629 (arch::breakpoint: avoid confusing 'equivalent' terminology)

Don't try to skip anything in `Skip::advance_by(0)` If we try to eagerly process our skip count, we might see the end of the inner iterator. `Iterator::advance_by` is supposed to return a non-zero `Err` count when exhausted, but there's no room for `Skip` to report anything in this case. So, it's better that we don't even try. Fixes rust-lang#164480

…uwer Rollup of 14 pull requests Successful merges: - #163664 (Add new `RUSTC_BOOTSTRAP=-allow-unstable-compiler-flags` mode for testing stable compiler behavior in UI tests) - #163104 ([debuginfo] Emit `usize` and `isize` as typedefs) - #163701 (add ReadDir::dir to get the directory handle of the underlying directory) - #164488 (Don't try to skip anything in `Skip::advance_by(0)`) - #164611 (Improve bit permutation codegen) - #164612 (std: Combine `is_powerpc64_feature_detected` into `is_powerpc_feature_detected`) - #148842 (Avoid incorrect lifetime suggestion involving `sym::anon`) - #162668 (document that `!` does bitwise and logical negation) - #164264 (lint: suggest `fXX::is_nan` for unsuffixed NaN comparisons) - #164509 (layout invariant: turn delayed bug back into proper assertion) - #164540 (Minor optimizations around macro parsing) - #164594 (rustdoc: Correctly handle inner `deprecated` attribute on modules) - #164595 (Allow attributes in function trait parameters) - #164629 (arch::breakpoint: avoid confusing 'equivalent' terminology)

Don't try to skip anything in `Skip::advance_by(0)` If we try to eagerly process our skip count, we might see the end of the inner iterator. `Iterator::advance_by` is supposed to return a non-zero `Err` count when exhausted, but there's no room for `Skip` to report anything in this case. So, it's better that we don't even try. Fixes rust-lang#164480

…uwer Rollup of 19 pull requests Successful merges: - #163664 (Add new `RUSTC_BOOTSTRAP=-allow-unstable-compiler-flags` mode for testing stable compiler behavior in UI tests) - #163668 (Remap syntax contexts and expansion ids for det. metadata encoding) - #160404 (fd-views: AsRef<File>&Co. for BorrowedFd) - #163104 ([debuginfo] Emit `usize` and `isize` as typedefs) - #163317 (Stop useless caching of post-LTO artifact caching for fat LTO) - #163701 (add ReadDir::dir to get the directory handle of the underlying directory) - #164488 (Don't try to skip anything in `Skip::advance_by(0)`) - #164507 (Encode HashMap and HashSet in deterministic order when an encoder requires determinism) - #164611 (Improve bit permutation codegen) - #164612 (std: Combine `is_powerpc64_feature_detected` into `is_powerpc_feature_detected`) - #148842 (Avoid incorrect lifetime suggestion involving `sym::anon`) - #162668 (document that `!` does bitwise and logical negation) - #164264 (lint: suggest `fXX::is_nan` for unsuffixed NaN comparisons) - #164509 (layout invariant: turn delayed bug back into proper assertion) - #164540 (Minor optimizations around macro parsing) - #164594 (rustdoc: Correctly handle inner `deprecated` attribute on modules) - #164595 (Allow attributes in function trait parameters) - #164641 (Stabilize `slice_split_once`) - #164646 (Adjust rustfmt subtree sync docs to not use `--allow-noop` for now)

Rollup of 20 pull requests Successful merges: - #163664 (Add new `RUSTC_BOOTSTRAP=-allow-unstable-compiler-flags` mode for testing stable compiler behavior in UI tests) - #163668 (Remap syntax contexts and expansion ids for det. metadata encoding) - #163104 ([debuginfo] Emit `usize` and `isize` as typedefs) - #163317 (Stop useless caching of post-LTO artifact caching for fat LTO) - #163701 (add ReadDir::dir to get the directory handle of the underlying directory) - #164488 (Don't try to skip anything in `Skip::advance_by(0)`) - #164507 (Encode HashMap and HashSet in deterministic order when an encoder requires determinism) - #164611 (Improve bit permutation codegen) - #164612 (std: Combine `is_powerpc64_feature_detected` into `is_powerpc_feature_detected`) - #148842 (Avoid incorrect lifetime suggestion involving `sym::anon`) - #162668 (document that `!` does bitwise and logical negation) - #164264 (lint: suggest `fXX::is_nan` for unsuffixed NaN comparisons) - #164509 (layout invariant: turn delayed bug back into proper assertion) - #164540 (Minor optimizations around macro parsing) - #164594 (rustdoc: Correctly handle inner `deprecated` attribute on modules) - #164595 (Allow attributes in function trait parameters) - #164616 (Add test for VecDeque with a custom allocator) - #164629 (arch::breakpoint: avoid confusing 'equivalent' terminology) - #164641 (Stabilize `slice_split_once`) - #164646 (Adjust rustfmt subtree sync docs to not use `--allow-noop` for now)

Rollup merge of #164488 - cuviper:skip0, r=JohnTitor Don't try to skip anything in `Skip::advance_by(0)` If we try to eagerly process our skip count, we might see the end of the inner iterator. `Iterator::advance_by` is supposed to return a non-zero `Err` count when exhausted, but there's no room for `Skip` to report anything in this case. So, it's better that we don't even try. Fixes #164480

Rollup of 20 pull requests Successful merges: - rust-lang/rust#163664 (Add new `RUSTC_BOOTSTRAP=-allow-unstable-compiler-flags` mode for testing stable compiler behavior in UI tests) - rust-lang/rust#163668 (Remap syntax contexts and expansion ids for det. metadata encoding) - rust-lang/rust#163104 ([debuginfo] Emit `usize` and `isize` as typedefs) - rust-lang/rust#163317 (Stop useless caching of post-LTO artifact caching for fat LTO) - rust-lang/rust#163701 (add ReadDir::dir to get the directory handle of the underlying directory) - rust-lang/rust#164488 (Don't try to skip anything in `Skip::advance_by(0)`) - rust-lang/rust#164507 (Encode HashMap and HashSet in deterministic order when an encoder requires determinism) - rust-lang/rust#164611 (Improve bit permutation codegen) - rust-lang/rust#164612 (std: Combine `is_powerpc64_feature_detected` into `is_powerpc_feature_detected`) - rust-lang/rust#148842 (Avoid incorrect lifetime suggestion involving `sym::anon`) - rust-lang/rust#162668 (document that `!` does bitwise and logical negation) - rust-lang/rust#164264 (lint: suggest `fXX::is_nan` for unsuffixed NaN comparisons) - rust-lang/rust#164509 (layout invariant: turn delayed bug back into proper assertion) - rust-lang/rust#164540 (Minor optimizations around macro parsing) - rust-lang/rust#164594 (rustdoc: Correctly handle inner `deprecated` attribute on modules) - rust-lang/rust#164595 (Allow attributes in function trait parameters) - rust-lang/rust#164616 (Add test for VecDeque with a custom allocator) - rust-lang/rust#164629 (arch::breakpoint: avoid confusing 'equivalent' terminology) - rust-lang/rust#164641 (Stabilize `slice_split_once`) - rust-lang/rust#164646 (Adjust rustfmt subtree sync docs to not use `--allow-noop` for now)

rustbot assigned JohnTitor Oct 17, 2026

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-libs Relevant to the library team, which will review and decide on the PR/issue. labels Oct 17, 2026

JohnTitor approved these changes Oct 20, 2026

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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 Oct 20, 2026

JonathanBrouwer mentioned this pull request Oct 20, 2026

Rollup of 6 pull requests #164630

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Rollup of 14 pull requests #164632

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Rollup of 13 pull requests #164634

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Rollup of 15 pull requests #164639

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Rollup of 14 pull requests #164640

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Rollup of 19 pull requests #164658

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jhpratt mentioned this pull request Oct 21, 2026

Rollup of 20 pull requests #164662

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rust-bors Bot merged commit fe5dc9e into rust-lang:main Oct 21, 2026
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rustbot added this to the 1.101.0 milestone Oct 21, 2026

github-actions Bot mentioned this pull request Oct 22, 2026

Toolchain upgrade to nightly-2026-10-22 flux-rs/flux#1847

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Don't try to skip anything in `Skip::advance_by(0)` - #164488

Don't try to skip anything in `Skip::advance_by(0)`#164488
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