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Merged
merged 1 commit into from
Aug 12, 2025
Merged

fix: re-enable self-assignment #145214

merged 1 commit into from
Aug 12, 2025

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notJoon
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@notJoon notJoon commented Aug 10, 2025 •
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Description

Re-enables the self-assignment detection that was previously disabled due to unrelated regressions. The fix detects useless assignments like x = x and foo.field = foo.field.

History

The original regressions (#81626, #81658) were specifically about false positives in write-only field detection, not self-assignment detection. Belows are brief history for the rule that I understand.

This PR only re-enables the self-assignment checks, which are orthogonal to the problematic write-only field analysis.

Changes

  • Removed #[allow(dead_code)] from compiler/rustc_passes/src/dead.rs file
    • handle_assign and
    • check_for_self_assign
  • Added ExprKind::Assign handling in visit_expr to call both methods
  • Updated test expectations in tests/ui/lint/dead-code/self-assign.rs

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@rustbot 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. labels Aug 10, 2025
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bors commented Aug 11, 2025

📌 Commit ba350ff has been approved by petrochenkov

It is now in the queue for this repository.

@bors bors 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 Aug 11, 2025
fmease added a commit to fmease/rust that referenced this pull request Aug 11, 2025
@fmease
Rollup merge of rust-lang#145214 - notJoon:fix/enable-self-assignment…
8eeac6d 
…, r=petrochenkov

fix: re-enable self-assignment

## Description

Re-enables the self-assignment detection that was previously disabled due to unrelated regressions. The fix detects useless assignments like `x = x` and `foo.field = foo.field`.

## History

The original regressions (rust-lang#81626, rust-lang#81658) were specifically about false positives in write-only field detection, not self-assignment detection. Belows are brief history for the rule that I understand.

- Self-assignment detection was originally implemented in rust-lang#87129 to address rust-lang#75356
- The implementation was disabled alongside the revert of rust-lang#81473's "write-only fields" detection
- rust-lang#81473 was reverted via rust-lang#86212 and rust-lang#83171 due to false positives in write-only field detection (rust-lang#81626, rust-lang#81658)
- The self-assignment detection feature got removed, even though it wasn't the reason for the problems

This PR only re-enables the self-assignment checks, which are orthogonal to the problematic write-only field analysis.

## Changes
- Removed `#[allow(dead_code)]` from `compiler/rustc_passes/src/dead.rs` file
    - `handle_assign` and
    - `check_for_self_assign`
- Added `ExprKind::Assign` handling in `visit_expr` to call both methods
- Updated test expectations in `tests/ui/lint/dead-code/self-assign.rs`
@fmease fmease mentioned this pull request Aug 11, 2025
Closed
fmease added a commit to fmease/rust that referenced this pull request Aug 12, 2025
@fmease
Rollup merge of rust-lang#145214 - notJoon:fix/enable-self-assignment…
e54c1d4 
…, r=petrochenkov

fix: re-enable self-assignment

## Description

Re-enables the self-assignment detection that was previously disabled due to unrelated regressions. The fix detects useless assignments like `x = x` and `foo.field = foo.field`.

## History

The original regressions (rust-lang#81626, rust-lang#81658) were specifically about false positives in write-only field detection, not self-assignment detection. Belows are brief history for the rule that I understand.

- Self-assignment detection was originally implemented in rust-lang#87129 to address rust-lang#75356
- The implementation was disabled alongside the revert of rust-lang#81473's "write-only fields" detection
- rust-lang#81473 was reverted via rust-lang#86212 and rust-lang#83171 due to false positives in write-only field detection (rust-lang#81626, rust-lang#81658)
- The self-assignment detection feature got removed, even though it wasn't the reason for the problems

This PR only re-enables the self-assignment checks, which are orthogonal to the problematic write-only field analysis.

## Changes
- Removed `#[allow(dead_code)]` from `compiler/rustc_passes/src/dead.rs` file
    - `handle_assign` and
    - `check_for_self_assign`
- Added `ExprKind::Assign` handling in `visit_expr` to call both methods
- Updated test expectations in `tests/ui/lint/dead-code/self-assign.rs`
@fmease fmease mentioned this pull request Aug 12, 2025
Closed
fmease added a commit to fmease/rust that referenced this pull request Aug 12, 2025
@fmease
Rollup merge of rust-lang#145214 - notJoon:fix/enable-self-assignment…
bc71652 
…, r=petrochenkov

fix: re-enable self-assignment

## Description

Re-enables the self-assignment detection that was previously disabled due to unrelated regressions. The fix detects useless assignments like `x = x` and `foo.field = foo.field`.

## History

The original regressions (rust-lang#81626, rust-lang#81658) were specifically about false positives in write-only field detection, not self-assignment detection. Belows are brief history for the rule that I understand.

- Self-assignment detection was originally implemented in rust-lang#87129 to address rust-lang#75356
- The implementation was disabled alongside the revert of rust-lang#81473's "write-only fields" detection
- rust-lang#81473 was reverted via rust-lang#86212 and rust-lang#83171 due to false positives in write-only field detection (rust-lang#81626, rust-lang#81658)
- The self-assignment detection feature got removed, even though it wasn't the reason for the problems

This PR only re-enables the self-assignment checks, which are orthogonal to the problematic write-only field analysis.

## Changes
- Removed `#[allow(dead_code)]` from `compiler/rustc_passes/src/dead.rs` file
    - `handle_assign` and
    - `check_for_self_assign`
- Added `ExprKind::Assign` handling in `visit_expr` to call both methods
- Updated test expectations in `tests/ui/lint/dead-code/self-assign.rs`
fmease added a commit to fmease/rust that referenced this pull request Aug 12, 2025
@fmease
Rollup merge of rust-lang#145214 - notJoon:fix/enable-self-assignment…
9f7f2ac 
…, r=petrochenkov

fix: re-enable self-assignment

## Description

Re-enables the self-assignment detection that was previously disabled due to unrelated regressions. The fix detects useless assignments like `x = x` and `foo.field = foo.field`.

## History

The original regressions (rust-lang#81626, rust-lang#81658) were specifically about false positives in write-only field detection, not self-assignment detection. Belows are brief history for the rule that I understand.

- Self-assignment detection was originally implemented in rust-lang#87129 to address rust-lang#75356
- The implementation was disabled alongside the revert of rust-lang#81473's "write-only fields" detection
- rust-lang#81473 was reverted via rust-lang#86212 and rust-lang#83171 due to false positives in write-only field detection (rust-lang#81626, rust-lang#81658)
- The self-assignment detection feature got removed, even though it wasn't the reason for the problems

This PR only re-enables the self-assignment checks, which are orthogonal to the problematic write-only field analysis.

## Changes
- Removed `#[allow(dead_code)]` from `compiler/rustc_passes/src/dead.rs` file
    - `handle_assign` and
    - `check_for_self_assign`
- Added `ExprKind::Assign` handling in `visit_expr` to call both methods
- Updated test expectations in `tests/ui/lint/dead-code/self-assign.rs`
@fmease fmease mentioned this pull request Aug 12, 2025
Closed
bors added a commit that referenced this pull request Aug 12, 2025
@bors
Auto merge of #145282 - fmease:rollup-1hpb5q5, r=fmease
c274350 
Rollup of 15 pull requests

Successful merges:

 - #131477 (Apple: Always pass SDK root when linking with `cc`, and pass it via `SDKROOT` env var)
 - #139806 (std: sys: pal: uefi: Overhaul Time)
 - #144386 (Extract TraitImplHeader in AST/HIR)
 - #144542 (Stabilize `sse4a` and `tbm` target features)
 - #144921 (Don't emit `rustdoc::broken_intra_doc_links` for GitHub-flavored Markdown admonitions like `[!NOTE]`)
 - #145155 (Port `#[allow_internal_unsafe]` to the new attribute system (attempt 2))
 - #145214 (fix: re-enable self-assignment)
 - #145216 (rustdoc: correct negative-to-implicit discriminant display)
 - #145238 (Tweak invalid builtin attribute output)
 - #145249 (Rename entered trace span variables from `_span` to  `_trace`)
 - #145251 (Support using #[unstable_feature_bound] on trait)
 - #145253 (Document compiler and stdlib in stage1 in `pr-check-2` CI job)
 - #145260 (Make explicit guarantees about `Vec`’s allocator)
 - #145263 (Update books)
 - #145273 (Account for new `assert!` desugaring in `!condition` suggestion)

r? `@ghost`
`@rustbot` modify labels: rollup
fmease added a commit to fmease/rust that referenced this pull request Aug 12, 2025
@fmease
Rollup merge of rust-lang#145214 - notJoon:fix/enable-self-assignment…
e92800a 
…, r=petrochenkov

fix: re-enable self-assignment

## Description

Re-enables the self-assignment detection that was previously disabled due to unrelated regressions. The fix detects useless assignments like `x = x` and `foo.field = foo.field`.

## History

The original regressions (rust-lang#81626, rust-lang#81658) were specifically about false positives in write-only field detection, not self-assignment detection. Belows are brief history for the rule that I understand.

- Self-assignment detection was originally implemented in rust-lang#87129 to address rust-lang#75356
- The implementation was disabled alongside the revert of rust-lang#81473's "write-only fields" detection
- rust-lang#81473 was reverted via rust-lang#86212 and rust-lang#83171 due to false positives in write-only field detection (rust-lang#81626, rust-lang#81658)
- The self-assignment detection feature got removed, even though it wasn't the reason for the problems

This PR only re-enables the self-assignment checks, which are orthogonal to the problematic write-only field analysis.

## Changes
- Removed `#[allow(dead_code)]` from `compiler/rustc_passes/src/dead.rs` file
    - `handle_assign` and
    - `check_for_self_assign`
- Added `ExprKind::Assign` handling in `visit_expr` to call both methods
- Updated test expectations in `tests/ui/lint/dead-code/self-assign.rs`
@fmease fmease mentioned this pull request Aug 12, 2025
Closed
bors added a commit that referenced this pull request Aug 12, 2025
@bors
Auto merge of #145285 - fmease:rollup-pm365d3, r=fmease
67f4494 
Rollup of 14 pull requests

Successful merges:

 - #131477 (Apple: Always pass SDK root when linking with `cc`, and pass it via `SDKROOT` env var)
 - #139806 (std: sys: pal: uefi: Overhaul Time)
 - #144210 (std: thread: Return error if setting thread stack size fails)
 - #144386 (Extract TraitImplHeader in AST/HIR)
 - #144921 (Don't emit `rustdoc::broken_intra_doc_links` for GitHub-flavored Markdown admonitions like `[!NOTE]`)
 - #145155 (Port `#[allow_internal_unsafe]` to the new attribute system (attempt 2))
 - #145214 (fix: re-enable self-assignment)
 - #145216 (rustdoc: correct negative-to-implicit discriminant display)
 - #145238 (Tweak invalid builtin attribute output)
 - #145249 (Rename entered trace span variables from `_span` to  `_trace`)
 - #145251 (Support using #[unstable_feature_bound] on trait)
 - #145253 (Document compiler and stdlib in stage1 in `pr-check-2` CI job)
 - #145263 (Update books)
 - #145273 (Account for new `assert!` desugaring in `!condition` suggestion)

r? `@ghost`
`@rustbot` modify labels: rollup
Zalathar added a commit to Zalathar/rust that referenced this pull request Aug 12, 2025
@Zalathar
Rollup merge of rust-lang#145214 - notJoon:fix/enable-self-assignment…
93e2056 
…, r=petrochenkov

fix: re-enable self-assignment

## Description

Re-enables the self-assignment detection that was previously disabled due to unrelated regressions. The fix detects useless assignments like `x = x` and `foo.field = foo.field`.

## History

The original regressions (rust-lang#81626, rust-lang#81658) were specifically about false positives in write-only field detection, not self-assignment detection. Belows are brief history for the rule that I understand.

- Self-assignment detection was originally implemented in rust-lang#87129 to address rust-lang#75356
- The implementation was disabled alongside the revert of rust-lang#81473's "write-only fields" detection
- rust-lang#81473 was reverted via rust-lang#86212 and rust-lang#83171 due to false positives in write-only field detection (rust-lang#81626, rust-lang#81658)
- The self-assignment detection feature got removed, even though it wasn't the reason for the problems

This PR only re-enables the self-assignment checks, which are orthogonal to the problematic write-only field analysis.

## Changes
- Removed `#[allow(dead_code)]` from `compiler/rustc_passes/src/dead.rs` file
    - `handle_assign` and
    - `check_for_self_assign`
- Added `ExprKind::Assign` handling in `visit_expr` to call both methods
- Updated test expectations in `tests/ui/lint/dead-code/self-assign.rs`
@Zalathar Zalathar mentioned this pull request Aug 12, 2025
Closed
bors added a commit that referenced this pull request Aug 12, 2025
@bors
Auto merge of #145293 - Zalathar:rollup-rsp9t9l, r=Zalathar
1c7121c 
Rollup of 17 pull requests

Successful merges:

 - #131477 (Apple: Always pass SDK root when linking with `cc`, and pass it via `SDKROOT` env var)
 - #139806 (std: sys: pal: uefi: Overhaul Time)
 - #144210 (std: thread: Return error if setting thread stack size fails)
 - #144386 (Extract TraitImplHeader in AST/HIR)
 - #144921 (Don't emit `rustdoc::broken_intra_doc_links` for GitHub-flavored Markdown admonitions like `[!NOTE]`)
 - #145155 (Port `#[allow_internal_unsafe]` to the new attribute system (attempt 2))
 - #145214 (fix: re-enable self-assignment)
 - #145216 (rustdoc: correct negative-to-implicit discriminant display)
 - #145238 (Tweak invalid builtin attribute output)
 - #145249 (Rename entered trace span variables from `_span` to  `_trace`)
 - #145251 (Support using #[unstable_feature_bound] on trait)
 - #145253 (Document compiler and stdlib in stage1 in `pr-check-2` CI job)
 - #145260 (Make explicit guarantees about `Vec`’s allocator)
 - #145263 (Update books)
 - #145273 (Account for new `assert!` desugaring in `!condition` suggestion)
 - #145283 (Make I-miscompile imply I-prioritize)
 - #145291 (bootstrap: Only warn about `rust.debug-assertions` if downloading rustc)

r? `@ghost`
`@rustbot` modify labels: rollup
@Zalathar Zalathar mentioned this pull request Aug 12, 2025
Merged
bors added a commit that referenced this pull request Aug 12, 2025
@bors
Auto merge of #145300 - Zalathar:rollup-0eqbt6a, r=Zalathar
d9dba3a 
Rollup of 17 pull requests

Successful merges:

 - #131477 (Apple: Always pass SDK root when linking with `cc`, and pass it via `SDKROOT` env var)
 - #139806 (std: sys: pal: uefi: Overhaul Time)
 - #144386 (Extract TraitImplHeader in AST/HIR)
 - #144921 (Don't emit `rustdoc::broken_intra_doc_links` for GitHub-flavored Markdown admonitions like `[!NOTE]`)
 - #145155 (Port `#[allow_internal_unsafe]` to the new attribute system (attempt 2))
 - #145214 (fix: re-enable self-assignment)
 - #145216 (rustdoc: correct negative-to-implicit discriminant display)
 - #145238 (Tweak invalid builtin attribute output)
 - #145249 (Rename entered trace span variables from `_span` to  `_trace`)
 - #145251 (Support using #[unstable_feature_bound] on trait)
 - #145253 (Document compiler and stdlib in stage1 in `pr-check-2` CI job)
 - #145260 (Make explicit guarantees about `Vec`’s allocator)
 - #145263 (Update books)
 - #145273 (Account for new `assert!` desugaring in `!condition` suggestion)
 - #145283 (Make I-miscompile imply I-prioritize)
 - #145291 (bootstrap: Only warn about `rust.debug-assertions` if downloading rustc)
 - #145292 (Fix a typo in range docs)

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit 55cb4b2 into rust-lang:master Aug 12, 2025
10 checks passed
@rustbot rustbot added this to the 1.91.0 milestone Aug 12, 2025
rust-timer added a commit that referenced this pull request Aug 12, 2025
@rust-timer
Unrolled build for #145214
b58963b 
Rollup merge of #145214 - notJoon:fix/enable-self-assignment, r=petrochenkov

fix: re-enable self-assignment

## Description

Re-enables the self-assignment detection that was previously disabled due to unrelated regressions. The fix detects useless assignments like `x = x` and `foo.field = foo.field`.

## History

The original regressions (#81626, #81658) were specifically about false positives in write-only field detection, not self-assignment detection. Belows are brief history for the rule that I understand.

- Self-assignment detection was originally implemented in #87129 to address #75356
- The implementation was disabled alongside the revert of #81473's "write-only fields" detection
- #81473 was reverted via #86212 and #83171 due to false positives in write-only field detection (#81626, #81658)
- The self-assignment detection feature got removed, even though it wasn't the reason for the problems

This PR only re-enables the self-assignment checks, which are orthogonal to the problematic write-only field analysis.

## Changes
- Removed `#[allow(dead_code)]` from `compiler/rustc_passes/src/dead.rs` file
    - `handle_assign` and
    - `check_for_self_assign`
- Added `ExprKind::Assign` handling in `visit_expr` to call both methods
- Updated test expectations in `tests/ui/lint/dead-code/self-assign.rs`
@notJoon notJoon deleted the fix/enable-self-assignment branch August 13, 2025 00:22
github-actions bot pushed a commit to rust-lang/miri that referenced this pull request Aug 13, 2025
@bors
Auto merge of #145300 - Zalathar:rollup-0eqbt6a, r=Zalathar
f393c32 
Rollup of 17 pull requests

Successful merges:

 - rust-lang/rust#131477 (Apple: Always pass SDK root when linking with `cc`, and pass it via `SDKROOT` env var)
 - rust-lang/rust#139806 (std: sys: pal: uefi: Overhaul Time)
 - rust-lang/rust#144386 (Extract TraitImplHeader in AST/HIR)
 - rust-lang/rust#144921 (Don't emit `rustdoc::broken_intra_doc_links` for GitHub-flavored Markdown admonitions like `[!NOTE]`)
 - rust-lang/rust#145155 (Port `#[allow_internal_unsafe]` to the new attribute system (attempt 2))
 - rust-lang/rust#145214 (fix: re-enable self-assignment)
 - rust-lang/rust#145216 (rustdoc: correct negative-to-implicit discriminant display)
 - rust-lang/rust#145238 (Tweak invalid builtin attribute output)
 - rust-lang/rust#145249 (Rename entered trace span variables from `_span` to  `_trace`)
 - rust-lang/rust#145251 (Support using #[unstable_feature_bound] on trait)
 - rust-lang/rust#145253 (Document compiler and stdlib in stage1 in `pr-check-2` CI job)
 - rust-lang/rust#145260 (Make explicit guarantees about `Vec`’s allocator)
 - rust-lang/rust#145263 (Update books)
 - rust-lang/rust#145273 (Account for new `assert!` desugaring in `!condition` suggestion)
 - rust-lang/rust#145283 (Make I-miscompile imply I-prioritize)
 - rust-lang/rust#145291 (bootstrap: Only warn about `rust.debug-assertions` if downloading rustc)
 - rust-lang/rust#145292 (Fix a typo in range docs)

r? `@ghost`
`@rustbot` modify labels: rollup
github-actions bot pushed a commit to rust-lang/rustc-dev-guide that referenced this pull request Aug 18, 2025
@bors
Auto merge of #145300 - Zalathar:rollup-0eqbt6a, r=Zalathar
7978029 
Rollup of 17 pull requests

Successful merges:

 - rust-lang/rust#131477 (Apple: Always pass SDK root when linking with `cc`, and pass it via `SDKROOT` env var)
 - rust-lang/rust#139806 (std: sys: pal: uefi: Overhaul Time)
 - rust-lang/rust#144386 (Extract TraitImplHeader in AST/HIR)
 - rust-lang/rust#144921 (Don't emit `rustdoc::broken_intra_doc_links` for GitHub-flavored Markdown admonitions like `[!NOTE]`)
 - rust-lang/rust#145155 (Port `#[allow_internal_unsafe]` to the new attribute system (attempt 2))
 - rust-lang/rust#145214 (fix: re-enable self-assignment)
 - rust-lang/rust#145216 (rustdoc: correct negative-to-implicit discriminant display)
 - rust-lang/rust#145238 (Tweak invalid builtin attribute output)
 - rust-lang/rust#145249 (Rename entered trace span variables from `_span` to  `_trace`)
 - rust-lang/rust#145251 (Support using #[unstable_feature_bound] on trait)
 - rust-lang/rust#145253 (Document compiler and stdlib in stage1 in `pr-check-2` CI job)
 - rust-lang/rust#145260 (Make explicit guarantees about `Vec`’s allocator)
 - rust-lang/rust#145263 (Update books)
 - rust-lang/rust#145273 (Account for new `assert!` desugaring in `!condition` suggestion)
 - rust-lang/rust#145283 (Make I-miscompile imply I-prioritize)
 - rust-lang/rust#145291 (bootstrap: Only warn about `rust.debug-assertions` if downloading rustc)
 - rust-lang/rust#145292 (Fix a typo in range docs)

r? `@ghost`
`@rustbot` modify labels: rollup
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