Revert "Remove redundant dyn-compatibility check." by theemathas · Pull Request #158665 · rust-lang/rust

theemathas · 2026-07-01T15:53:23Z

This reverts commit 5fad8a6.

rustbot · 2026-07-01T15:53:28Z

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fmease · 2026-07-01T16:01:49Z

Could you add a regression test?

Kivooeo

r=me after adding a test

View changes since this review

theemathas · 2026-07-02T03:46:08Z

@rustbot r=@Kivooeo

theemathas · 2026-07-02T03:48:30Z

@bors r=@Kivooeo

rust-bors · 2026-07-02T03:48:34Z

📌 Commit 2906b05 has been approved by Kivooeo

It is now in the queue for this repository.

Kivooeo · 2026-07-02T03:53:09Z

@bors r-

Hold on 😅, I didn't except you will add any comments, I need to check one small thing myself and likely to fix comments

rust-bors · 2026-07-02T03:53:13Z

This pull request was unapproved.

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theemathas · 2026-07-02T04:00:59Z

Whoops. Sorry.

Kivooeo

I think it's fine to remove both comments since this is never reached with new solver

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theemathas · 2026-07-02T08:55:27Z

I've applied the suggested comments, although I still don't quite understand everything that's going on.

This is hopefully ready to merge. Sorry for the trouble.

Kivooeo · 2026-07-02T08:59:03Z

Thanks!

Sorry for the trouble

There's no trouble at all, it's all right

r=me,lcnr with ci green

theemathas · 2026-07-02T11:13:00Z

@bors r=Kivooeo,lcnr

rust-bors · 2026-07-02T11:13:03Z

📌 Commit 50181ca has been approved by Kivooeo,lcnr

It is now in the queue for this repository.

🌲 The tree is currently closed for pull requests below priority 1000. This pull request will be tested once the tree is reopened.

… r=Kivooeo,lcnr Revert "Remove redundant dyn-compatibility check." This reverts commit 5fad8a6. Fixes rust-lang#158656 See rust-lang#158665 (comment) for explanation.

…uwer Rollup of 22 pull requests Successful merges: - #155429 (Support `u128`/`i128` c-variadic arguments) - #158100 (Emit retags in codegen to support BorrowSanitizer (part 4)) - #158494 (Improve E0277 diagnostics for conditionally implemented traits) - #158606 (use ProjectionPredicate instead of AliasRelate) - #158627 (Simplify option-iterator flattening in the compiler) - #158658 (Update LLVM submodule) - #158665 (Revert "Remove redundant dyn-compatibility check.") - #158021 (Remove old MinGW workaround) - #158473 (Add `riscv32imfc-unknown-none-elf` bare-metal target) - #158549 (process::exec: using appropriate exit code on vxworks.) - #158585 (Improve diagnostic for too many super keywords) - #158637 (hir_ty_lowering: avoid self type lookup for inherent aliases) - #158651 (ptr doc: reduce use of unsafe block to where needed) - #158669 (Remove `src/tools/test-float-parse/Cargo.lock`) - #158674 (library: Polish transmute's `split_at_stdlib` example) - #158677 (Add extra splat tests) - #158680 (Avoid ICE for `NonZero<char>` in improper_ctypes) - #158681 (Remove unnecessary `Hash` derives from MIR types) - #158682 (Avoid delayed bug for disabled on_type_error arguments) - #158684 (Add missing generic test coverage for ```#[splat]```) - #158687 (Streamline `MacEager`) - #158688 (Cleanup attribute docs and add links to other mentioned attributes)

…uwer Rollup of 21 pull requests Successful merges: - #158100 (Emit retags in codegen to support BorrowSanitizer (part 4)) - #158494 (Improve E0277 diagnostics for conditionally implemented traits) - #158606 (use ProjectionPredicate instead of AliasRelate) - #158627 (Simplify option-iterator flattening in the compiler) - #158658 (Update LLVM submodule) - #158665 (Revert "Remove redundant dyn-compatibility check.") - #158021 (Remove old MinGW workaround) - #158473 (Add `riscv32imfc-unknown-none-elf` bare-metal target) - #158549 (process::exec: using appropriate exit code on vxworks.) - #158585 (Improve diagnostic for too many super keywords) - #158637 (hir_ty_lowering: avoid self type lookup for inherent aliases) - #158651 (ptr doc: reduce use of unsafe block to where needed) - #158669 (Remove `src/tools/test-float-parse/Cargo.lock`) - #158674 (library: Polish transmute's `split_at_stdlib` example) - #158677 (Add extra splat tests) - #158680 (Avoid ICE for `NonZero<char>` in improper_ctypes) - #158681 (Remove unnecessary `Hash` derives from MIR types) - #158682 (Avoid delayed bug for disabled on_type_error arguments) - #158684 (Add missing generic test coverage for ```#[splat]```) - #158687 (Streamline `MacEager`) - #158688 (Cleanup attribute docs and add links to other mentioned attributes)

Rollup merge of #158665 - theemathas:undel-dyn-compat-check, r=Kivooeo,lcnr Revert "Remove redundant dyn-compatibility check." This reverts commit 5fad8a6. Fixes #158656 See #158665 (comment) for explanation.

JonathanBrouwer · 2026-07-05T12:18:09Z

@rust-timer build 7017bac

rust-timer · 2026-07-05T12:18:12Z

Missing artifact for sha 7017bac6dc0325f4d9692f4704ec5eb04824e66b (https://ci-artifacts.rust-lang.org/rustc-builds/7017bac6dc0325f4d9692f4704ec5eb04824e66b/rustc-nightly-x86_64-unknown-linux-gnu.tar.xz); not built yet, try again later.

Kobzol · 2026-07-05T14:45:33Z

@rust-timer build 7017bac

rust-timer · 2026-07-05T15:26:14Z

Finished benchmarking commit (7017bac): comparison URL.

Overall result: no relevant changes - no action needed

Benchmarking means the PR may be perf-sensitive. Consider adding rollup=never if this change is not fit for rolling up.

@rustbot label: -S-waiting-on-perf -perf-regression

Instruction count

This perf run didn't have relevant results for this metric.

Max RSS (memory usage)

Results (primary 5.4%, secondary -4.7%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	5.4%	[5.4%, 5.4%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-4.7%	[-6.7%, -2.8%]	2
All ❌✅ (primary)	5.4%	[5.4%, 5.4%]	1

Cycles

Results (primary -2.3%, secondary 2.6%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.6%	[2.2%, 3.1%]	3
Improvements ✅ (primary)	-2.3%	[-2.3%, -2.3%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-2.3%	[-2.3%, -2.3%]	1

Binary size

This perf run didn't have relevant results for this metric.

Bootstrap: 489.274s -> 489.871s (0.12%)
Artifact size: 393.40 MiB -> 393.44 MiB (0.01%)

Revert "Remove redundant dyn-compatibility check."

fe85327

This reverts commit 5fad8a6.

rustbot assigned Kivooeo Jul 1, 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. labels Jul 1, 2026

Kivooeo approved these changes Jul 1, 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 Jul 2, 2026

rust-bors Bot added the S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. label Jul 2, 2026

rust-bors Bot removed the S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. label Jul 2, 2026

Kivooeo reviewed Jul 2, 2026

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Comment thread tests/ui/impl-trait/rpit/dyn-in-nested-rpit.rs Outdated

lcnr reviewed Jul 2, 2026

View reviewed changes

Comment thread compiler/rustc_trait_selection/src/traits/select/mod.rs Outdated

Add test and comment for rust-lang#158656

50181ca

theemathas force-pushed the undel-dyn-compat-check branch from 2906b05 to 50181ca Compare July 2, 2026 08:54

theemathas added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Jul 2, 2026

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 2, 2026

JonathanBrouwer mentioned this pull request Jul 2, 2026

Rollup of 22 pull requests #158700

Closed

JonathanBrouwer mentioned this pull request Jul 5, 2026

Rollup of 21 pull requests #158795

Merged

rust-bors Bot merged commit 988fe15 into rust-lang:main Jul 5, 2026
13 checks passed

rustbot added this to the 1.98.0 milestone Jul 5, 2026

theemathas deleted the undel-dyn-compat-check branch July 5, 2026 11:06

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Overall result: no relevant changes - no action needed

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