Merge three `MaxUniverse`s into one by adwinwhite · Pull Request #158951 · rust-lang/rust

adwinwhite · 2026-07-08T08:26:19Z

We have three similar visitors to find the max universe of a value. They differ only in whether they consider infers, placeholders or both.

I think this is a small refactor without any behavior impact.
r? @ShoyuVanilla or @khyperia

rustbot · 2026-07-08T08:26:23Z

changes to the core type system

cc @lcnr

rustbot · 2026-07-08T08:26:25Z

ShoyuVanilla is currently at their maximum review capacity.
They may take a while to respond.

adwinwhite · 2026-07-08T08:27:43Z

Wonder whether the resolve_vars_if_possible causes perf regression.
@bors try @rust-timer queue

Merge three `MaxUniverse`s into one

rust-bors · 2026-07-08T10:34:40Z

☀️ Try build successful (CI)
Build commit: d38b46e (d38b46ead03071b39dde8bbe959f68f764519d6b)
Base parent: 99576cf (99576cf2ebc870c305225e9856b9423228872c56)

rust-timer · 2026-07-08T12:27:09Z

Finished benchmarking commit (d38b46e): 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 (secondary 4.4%)

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)	4.4%	[4.4%, 4.4%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Cycles

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

Binary size

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

Bootstrap: 488.508s -> 490.004s (0.31%)
Artifact size: 388.95 MiB -> 388.46 MiB (-0.13%)

ShoyuVanilla

@bors r+ rollup

View changes since this review

rust-bors · 2026-07-08T12:30:35Z

📌 Commit 1818498 has been approved by ShoyuVanilla

It is now in the queue for this repository.

@ShoyuVanilla

…hoyuVanilla Merge three `MaxUniverse`s into one We have three similar visitors to find the max universe of a value. They differ only in whether they consider infers, placeholders or both. I think this is a small refactor without any behavior impact. r? @ShoyuVanilla or @khyperia

…uwer Rollup of 18 pull requests Successful merges: - #158871 (add relnotes for 1.97.0) - #150946 (intrinsics: Add a fallback for non-const libm float functions) - #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`) - #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`) - #151379 (Stabilize `VecDeque::retain_back` from `truncate_front`) - #158807 (Add regression test for CString::clone_into unwind safety) - #158862 (Fix the span for parameter suggestion ) - #158883 (tests: fix enum-match.rs to handle LLVM 23) - #158894 (Make the ordering of non-terminal binds in ambiguity error messages deterministic) - #158902 (add codegen test for range length bound propagation) - #158913 (Update `browser-ui-test` version to `0.24.1`) - #158935 (std: support real fd methods on Emscripten) - #158951 (Merge three `MaxUniverse`s into one)

@ShoyuVanilla

…hoyuVanilla Merge three `MaxUniverse`s into one We have three similar visitors to find the max universe of a value. They differ only in whether they consider infers, placeholders or both. I think this is a small refactor without any behavior impact. r? @ShoyuVanilla or @khyperia

…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")

@ShoyuVanilla

…hoyuVanilla Merge three `MaxUniverse`s into one We have three similar visitors to find the max universe of a value. They differ only in whether they consider infers, placeholders or both. I think this is a small refactor without any behavior impact. r? @ShoyuVanilla or @khyperia

@ShoyuVanilla

…hoyuVanilla Merge three `MaxUniverse`s into one We have three similar visitors to find the max universe of a value. They differ only in whether they consider infers, placeholders or both. I think this is a small refactor without any behavior impact. r? @ShoyuVanilla or @khyperia

@ShoyuVanilla

…hoyuVanilla Merge three `MaxUniverse`s into one We have three similar visitors to find the max universe of a value. They differ only in whether they consider infers, placeholders or both. I think this is a small refactor without any behavior impact. r? @ShoyuVanilla or @khyperia

…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)

@ShoyuVanilla

…hoyuVanilla Merge three `MaxUniverse`s into one We have three similar visitors to find the max universe of a value. They differ only in whether they consider infers, placeholders or both. I think this is a small refactor without any behavior impact. r? @ShoyuVanilla or @khyperia

…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)

@ShoyuVanilla

…hoyuVanilla Merge three `MaxUniverse`s into one We have three similar visitors to find the max universe of a value. They differ only in whether they consider infers, placeholders or both. I think this is a small refactor without any behavior impact. r? @ShoyuVanilla or @khyperia

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)

@ShoyuVanilla

Rollup merge of #158951 - adwinwhite:unify-max-universe, r=ShoyuVanilla Merge three `MaxUniverse`s into one We have three similar visitors to find the max universe of a value. They differ only in whether they consider infers, placeholders or both. I think this is a small refactor without any behavior impact. r? @ShoyuVanilla or @khyperia

JonathanBrouwer · 2026-07-12T07:44:18Z

@rust-timer build d53d381

rust-timer · 2026-07-12T12:21:03Z

Finished benchmarking commit (d53d381): comparison URL.

Overall result: ❌✅ regressions and improvements - please read:

Benchmarking means the PR may be perf-sensitive. It's automatically marked not fit for rolling up. Overriding is possible but disadvised: it risks changing compiler perf.

Next, please: If you can, justify the regressions found in this try perf run in writing along with @rustbot label: +perf-regression-triaged. If not, fix the regressions and do another perf run. Neutral or positive results will clear the label automatically.

@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	0.4%	[0.3%, 0.4%]	2
Regressions ❌ (secondary)	0.1%	[0.0%, 0.2%]	9
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.1%	[-0.1%, -0.0%]	3
All ❌✅ (primary)	0.4%	[0.3%, 0.4%]	2

Max RSS (memory usage)

Results (primary -0.7%, secondary -1.8%)

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

	mean	range	count
Regressions ❌ (primary)	2.4%	[2.4%, 2.4%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-3.7%	[-3.7%, -3.7%]	1
Improvements ✅ (secondary)	-1.8%	[-3.5%, -1.0%]	3
All ❌✅ (primary)	-0.7%	[-3.7%, 2.4%]	2

Cycles

Results (secondary 1.2%)

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)	5.8%	[2.0%, 14.2%]	9
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.3%	[-9.2%, -1.5%]	9
All ❌✅ (primary)	-	-	0

Binary size

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

Bootstrap: 490.768s -> 489.423s (-0.27%)
Artifact size: 389.74 MiB -> 389.63 MiB (-0.03%)

JonathanBrouwer · 2026-07-12T20:16:05Z

@rustbot label: +perf-regression-triaged
Noise

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

unify MaxUniverses
1818498

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. WG-trait-system-refactor The Rustc Trait System Refactor Initiative (-Znext-solver) labels Jul 8, 2026

rustbot assigned ShoyuVanilla Jul 8, 2026

This comment has been minimized.
Sign in to view

rustbot added the S-waiting-on-perf Status: Waiting on a perf run to be completed. label Jul 8, 2026

This comment has been minimized.
Sign in to view

rust-borsBot pushed a commit that referenced this pull request Jul 8, 2026
Auto merge of#158951- adwinwhite:unify-max-universe, r=<try>
d38b46e
Merge three `MaxUniverse`s into one

This comment has been minimized.
Sign in to view

rustbot removed the S-waiting-on-perf Status: Waiting on a perf run to be completed. label Jul 8, 2026

ShoyuVanilla approved these changes Jul 8, 2026
View reviewed changes

rust-borsBot 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 8, 2026

JonathanBrouwer mentioned this pull request Jul 8, 2026
Rollup of 18 pull requests #158958
Closed

JonathanBrouwer mentioned this pull request Jul 9, 2026
Rollup of 17 pull requests #159007
Closed

JonathanBrouwer mentioned this pull request Jul 9, 2026
Rollup of 18 pull requests #159013
Closed

JonathanBrouwer mentioned this pull request Jul 9, 2026
Rollup of 21 pull requests #159020
Closed

JonathanBrouwer mentioned this pull request Jul 9, 2026
Rollup of 21 pull requests #159024
Closed

JonathanBrouwer mentioned this pull request Jul 9, 2026
Rollup of 24 pull requests #159037
Closed

This was referenced Jul 9, 2026
Rollup of 25 pull requests #159045
Closed
Rollup of 24 pull requests #159046
Merged

rust-borsBot merged commit 9a91b8f into rust-lang:mainJul 10, 2026
14 checks passed

rustbot added this to the 1.99.0 milestone Jul 10, 2026

This comment has been minimized.
Sign in to view

rustbot added the perf-regression Performance regression. label Jul 12, 2026

rustbot added the perf-regression-triaged The performance regression has been triaged. label Jul 12, 2026

lcnr mentioned this pull request Jul 14, 2026
Stabilize the next-generation trait solver rust-lang/goals#113
Open
8 tasks

Navigation Menu

Uh oh!

Uh oh!

Merge three `MaxUniverse`s into one - #158951

Merge three `MaxUniverse`s into one#158951
rust-bors[bot] merged 1 commit into
rust-lang:mainfrom
adwinwhite:unify-max-universe

adwinwhite commented Jul 8, 2026

Uh oh!

rustbot commented Jul 8, 2026

Uh oh!

rustbot commented Jul 8, 2026

Uh oh!

adwinwhite commented Jul 8, 2026

Uh oh!

This comment has been minimized.

This comment has been minimized.

rust-borsBot commented Jul 8, 2026

Uh oh!

This comment has been minimized.

rust-timer commented Jul 8, 2026

Uh oh!

ShoyuVanilla left a comment •
edited by rustbot
Loading

Uh oh!

rust-borsBot commented Jul 8, 2026

Uh oh!

Uh oh!

JonathanBrouwer commented Jul 12, 2026

Uh oh!

This comment has been minimized.

rust-timer commented Jul 12, 2026

Uh oh!

JonathanBrouwer commented Jul 12, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

5 participants

Uh oh!

Uh oh!

Conversation

adwinwhite commented Jul 8, 2026

Uh oh!

rustbot commented Jul 8, 2026

Uh oh!

rustbot commented Jul 8, 2026

Uh oh!

adwinwhite commented Jul 8, 2026

Uh oh!

This comment has been minimized.

This comment has been minimized.

rust-borsBot commented Jul 8, 2026

Uh oh!

This comment has been minimized.

rust-timer commented Jul 8, 2026

Overall result: no relevant changes - no action needed

Uh oh!

ShoyuVanilla left a comment • edited by rustbot Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

rust-borsBot commented Jul 8, 2026

Uh oh!

Uh oh!

JonathanBrouwer commented Jul 12, 2026

Uh oh!

This comment has been minimized.

rust-timer commented Jul 12, 2026

Overall result: ❌✅ regressions and improvements - please read:

Uh oh!

JonathanBrouwer commented Jul 12, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

5 participants

ShoyuVanilla left a comment •
edited by rustbot
Loading