Shallowly bail from `coerce_unsized` more #142941

compiler-errors · 2025-06-24T02:07:52Z

We do a lot of coercion in HIR typeck. Most of the time we're just coercing a type to itself, but we always try coerce_unsized even if it's not necessary.

Let's avoid doing that by adding a fast path to coerce_unsized; see the comment in that function.

compiler-errors · 2025-06-24T02:07:59Z

@bors try @rust-timer queue

bors · 2025-06-24T02:09:10Z

⌛ Trying commit e0b68fe with merge 6a35eeb...

[perf] Shallowly bail from `coerce_unsized` more

compiler-errors · 2025-06-24T02:34:40Z

TODO: test with a fast path for &str: CoerceUnsized<&str>.

bors · 2025-06-24T04:37:02Z

☀️ Try build successful - checks-actions
Build commit: 6a35eeb (6a35eeb37ae3dfbce8f5159463405fb81cddd28a)

rust-timer · 2025-06-24T16:24:17Z

Finished benchmarking commit (6a35eeb): comparison URL.

Overall result: ✅ improvements - no action needed

Benchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf.

@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
Regressions ❌ (secondary)	0.0%	[0.0%, 0.0%]	1
Improvements ✅ (primary)	-0.7%	[-4.5%, -0.1%]	60
Improvements ✅ (secondary)	-6.7%	[-21.6%, -0.1%]	58
All ❌✅ (primary)	-0.7%	[-4.5%, -0.1%]	60

Max RSS (memory usage)

Results (primary -1.2%, secondary -5.0%)

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)	2.3%	[2.3%, 2.3%]	1
Improvements ✅ (primary)	-1.2%	[-1.2%, -1.2%]	2
Improvements ✅ (secondary)	-5.8%	[-10.6%, -1.6%]	9
All ❌✅ (primary)	-1.2%	[-1.2%, -1.2%]	2

Cycles

Results (primary -4.5%, secondary -15.4%)

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)	-	-	0
Improvements ✅ (primary)	-4.5%	[-5.5%, -3.2%]	6
Improvements ✅ (secondary)	-15.4%	[-25.4%, -6.1%]	27
All ❌✅ (primary)	-4.5%	[-5.5%, -3.2%]	6

Binary size

Results (secondary -0.0%)

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)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.0%	[-0.0%, -0.0%]	1
All ❌✅ (primary)	-	-	0

Bootstrap: 688.989s -> 689.016s (0.00%)
Artifact size: 371.96 MiB -> 372.08 MiB (0.03%)

compiler-errors · 2025-06-24T16:36:36Z

holy fuck lol

compiler-errors · 2025-06-24T16:53:04Z

@bors2 try @rust-timer queue

rust-bors · 2025-06-24T16:53:08Z

⌛ Trying commit 3d115ac with merge 1eb1a24…

To cancel the try build, run the command @bors2 try cancel.

[perf] Shallowly bail from `coerce_unsized` more

compiler-errors · 2025-06-24T17:01:49Z

Anyways this is ready to review.

r? @lcnr

rustbot · 2025-06-24T17:01:49Z

r? @petrochenkov

rustbot has assigned @petrochenkov.
They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

Use r? to explicitly pick a reviewer

rust-bors · 2025-06-24T19:22:11Z

☀️ Try build successful (CI)
Build commit: 1eb1a24 (1eb1a24f58bb3d49e9be66d408afa9adf2b30a78, parent: 36b21637e93b038453924d3c66821089e71d8baa)

compiler-errors · 2025-06-24T22:52:07Z

Crashes should be fixed by #142976; they're only coincidentally fixed here by the fast path bc we don't end up trying coerce_unsized.

rust-timer · 2025-06-25T00:47:12Z

Finished benchmarking commit (1eb1a24): comparison URL.

Overall result: ✅ improvements - no action needed

Benchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf.

@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)	0.2%	[0.2%, 0.2%]	1
Regressions ❌ (secondary)	0.4%	[0.3%, 0.4%]	2
Improvements ✅ (primary)	-0.8%	[-4.5%, -0.1%]	80
Improvements ✅ (secondary)	-5.5%	[-21.6%, -0.0%]	73
All ❌✅ (primary)	-0.8%	[-4.5%, 0.2%]	81

Max RSS (memory usage)

Results (primary -0.9%, secondary -3.8%)

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

	mean	range	count
Regressions ❌ (primary)	1.3%	[1.3%, 1.3%]	1
Regressions ❌ (secondary)	3.9%	[3.9%, 4.0%]	2
Improvements ✅ (primary)	-3.1%	[-3.1%, -3.1%]	1
Improvements ✅ (secondary)	-5.2%	[-10.6%, -1.5%]	11
All ❌✅ (primary)	-0.9%	[-3.1%, 1.3%]	2

Cycles

Results (primary -2.0%, secondary -12.2%)

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)	-	-	0
Improvements ✅ (primary)	-2.0%	[-4.1%, -0.8%]	26
Improvements ✅ (secondary)	-12.2%	[-24.0%, -0.9%]	31
All ❌✅ (primary)	-2.0%	[-4.1%, -0.8%]	26

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 689.383s -> 687.827s (-0.23%)
Artifact size: 371.94 MiB -> 372.03 MiB (0.02%)

lcnr · 2025-06-25T05:54:04Z

compiler/rustc_hir_typeck/src/coercion.rs

@@ -515,11 +515,7 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
    ///
    /// [unsized coercion](https://doc.rust-lang.org/reference/type-coercions.html#unsized-coercions)
    #[instrument(skip(self), level = "debug")]
-    fn coerce_unsized(&self, mut source: Ty<'tcx>, mut target: Ty<'tcx>) -> CoerceResult<'tcx> {
-        source = self.shallow_resolve(source);
-        target = self.shallow_resolve(target);


why remove these, are we guaranteed that they are shallow resolved? if so, please convert them into debug asserts

yes, we shallowly resolve at the top of the coerce entrypoint

pls debug assert then

lcnr · 2025-06-25T05:56:45Z

compiler/rustc_hir_typeck/src/coercion.rs

+            | ty::Infer(ty::IntVar(_) | ty::FloatVar(_))
+            | ty::Str
+            | ty::Array(_, _)
+            | ty::Slice(_)


array to slice is always Deref an not CoerceUnsized? 🤔

Slices are the RHS for Unsize, not CoerceUnsized. The latter is for pointers not data.

ah yeah, remember how this works again/looked it up

lcnr · 2025-06-26T07:41:36Z

r=me after adding the debug asserts

compiler-errors · 2025-06-26T16:32:03Z

Added a bunch of debug assertions

@bors r=lcnr

bors · 2025-06-26T16:32:07Z

📌 Commit 0d37587 has been approved by lcnr

It is now in the queue for this repository.

Shallowly bail from `coerce_unsized` more We do a *lot* of coercion in HIR typeck. Most of the time we're just coercing a type to itself, but we always try `coerce_unsized` even if it's not necessary. Let's avoid doing that by adding a fast path to `coerce_unsized`; see the comment in that function.

bors · 2025-06-29T23:17:03Z

⌛ Testing commit 0d37587 with merge 3c67cf9...

rust-log-analyzer · 2025-06-30T01:45:07Z

The job x86_64-msvc-1 failed! Check out the build log: (web) (plain)

Click to see the possible cause of the failure (guessed by this bot)

---- [run-make] tests\run-make\short-ice stdout ----

error: rmake recipe failed to complete
status: exit code: 101
command: "D:\\a\\rust\\rust\\build\\x86_64-pc-windows-msvc\\test\\run-make\\short-ice\\rmake.exe"
stdout: none
--- stderr -------------------------------

thread 'main' panicked at D:\a\rust\rust\tests\run-make\short-ice\rmake.rs:38:5:
assertion `left == right` failed: Full backtrace should contain the short backtrace markers.
---
   2:     0x7ff91889b591 - std::io::IoSlice::as_slice::h28485194e6243426
   3:     0x7ff9188a6df5 - std::sys::backtrace::lock::h87d510c18ece35cf
   4:     0x7ff9188ace00 - std::panicking::default_hook::h627eeb82f5246f9e
   5:     0x7ff9188acb20 - std::panicking::default_hook::h627eeb82f5246f9e
   6:     0x7ff90f33d13e - RNvXss_NtCscm7aL0A7JxU_5alloc5boxedINtB5_3BoxNCNvCs59evyLnHgro_17rustc_driver_impl16install_ice_hooks_0EINtNtNtCs5ASmzjaxJJ1_4core3ops8function2FnTRDG0_IB1F_TRL1_INtNtCsdtfb8v2o8zK_3std5panic13PanicHookInfoL0_EEEp6OutputuNtNtB1L_6marker4SyncNtB3z_4SendEL_R
   7:     0x7ff9188adb17 - std::panicking::rust_panic_with_hook::h8466c30f6f83b753
   8:     0x7ff9188ad722 - <std::panicking::begin_panic_handler::StaticStrPayload as core::panic::PanicPayload>::take_box::h9d1193d33cbd6e6c
   9:     0x7ff9188a798f - std::sys::backtrace::__rust_end_short_backtrace::h10feac60716a86f8
  10:     0x7ff9188ad2ae - __rustc[b8115c53b2c32766]::rust_begin_unwind
  11:     0x7ff918bcd551 - core::panicking::panic_fmt::hbb8d79b163e744ad
  12:     0x7ff918350371 - <rustc_errors[92707a7cafc8f374]::DiagCtxtInner>::emit_diagnostic
  13:     0x7ff91834f019 - <rustc_errors[92707a7cafc8f374]::DiagCtxtInner>::emit_diagnostic
  14:     0x7ff90f762f6d - RNvXs_NtNtNtCs5ASmzjaxJJ1_4core4iter8adapters6clonedINtB4_6ClonedINtNtB6_5chain5ChainIB12_IB12_IB12_IB12_IB12_IB12_IB12_IB12_IB12_IB12_IB12_IB12_IB12_INtNtNtB8_7sources5empty5EmptyRTReNtNtCsdxMMCw4qQgX_12rustc_target15target_features9StabilityRSB2U_EEINtNt
  15:     0x7ff91834df28 - <rustc_errors[92707a7cafc8f374]::DiagCtxtInner>::emit_diagnostic
  16:     0x7ff91834c211 - <rustc_errors[92707a7cafc8f374]::DiagCtxtHandle>::emit_diagnostic
  17:     0x7ff9183ae28c - <rustc_span[f4a97dffebfbe3a3]::ErrorGuaranteed as rustc_errors[92707a7cafc8f374]::diagnostic::EmissionGuarantee>::emit_producing_guarantee
  18:     0x7ff914032681 - <rustc_hir_typeck[f3b43addd68d5c37]::fn_ctxt::FnCtxt>::check_repeat_exprs
  19:     0x7ff91402b69e - <rustc_hir_typeck[f3b43addd68d5c37]::fn_ctxt::FnCtxt>::check_repeat_exprs
  20:     0x7ff913fdff30 - <rustc_hir_typeck[f3b43addd68d5c37]::fn_ctxt::FnCtxt>::try_overloaded_call_traits
  21:     0x7ff9140d2f67 - <rustc_hir_typeck[f3b43addd68d5c37]::fn_ctxt::FnCtxt>::check_expr_kind
  22:     0x7ff913ff99ef - <rustc_hir_typeck[f3b43addd68d5c37]::fn_ctxt::FnCtxt>::check_expr_coercible_to_type
  23:     0x7ff9140c775e - <rustc_hir_typeck[f3b43addd68d5c37]::fn_ctxt::FnCtxt>::check_expr_with_expectation
  24:     0x7ff914039bca - <rustc_hir_typeck[f3b43addd68d5c37]::fn_ctxt::FnCtxt>::check_repeat_exprs
  25:     0x7ff9140c92b3 - <rustc_hir_typeck[f3b43addd68d5c37]::fn_ctxt::FnCtxt>::check_expr_kind
  26:     0x7ff913ff99ef - <rustc_hir_typeck[f3b43addd68d5c37]::fn_ctxt::FnCtxt>::check_expr_coercible_to_type
  27:     0x7ff9140c775e - <rustc_hir_typeck[f3b43addd68d5c37]::fn_ctxt::FnCtxt>::check_expr_with_expectation
  28:     0x7ff913ffba7f - <rustc_hir_typeck[f3b43addd68d5c37]::fn_ctxt::FnCtxt>::check_return_or_body_tail
  29:     0x7ff913f369e1 - rustc_hir_typeck[f3b43addd68d5c37]::check::check_fn
  30:     0x7ff913ea1ab2 - rustc_hir_typeck[f3b43addd68d5c37]::upvar::should_do_rust_2021_incompatible_closure_captures_analysis
  31:     0x7ff91694fb05 - rustc_query_impl[636a45210f4627b1]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[636a45210f4627b1]::query_impl::typeck::dynamic_query::{closure#2}::{closure#0}, rustc_middle[5d7d5661cb7251f6]::query::erase::Erased<[u8; 8usize]>>
  32:     0x7ff9168934f7 - rustc_query_impl[636a45210f4627b1]::query_impl::items_of_instance::get_query_incr::__rust_end_short_backtrace
  33:     0x7ff916792f1b - RINvNtNtCskdyPo4XOC2c_18rustc_query_system5query8plumbing17try_execute_queryINtCs8xbqABPlkTB_16rustc_query_impl13DynamicConfigINtNtCsaSadm4QJbrx_21rustc_data_structures9vec_cache8VecCacheNtNtCs2WfteshB2YX_9rustc_hir6hir_id7OwnerIdINtNtNtCs81DRtryM8Ze_12rus
  34:     0x7ff91658630d - rustc_query_impl[636a45210f4627b1]::query_impl::typeck::get_query_non_incr::__rust_end_short_backtrace
  35:     0x7ff9146097b9 - <u8 as <[_]>::to_vec_in::ConvertVec>::to_vec::<alloc[8fed1a6a76e824b4]::alloc::Global>
  36:     0x7ff9145f8005 - RINvNtNtCsaSadm4QJbrx_21rustc_data_structures4sync8parallel15par_for_each_inRNtNtCsl0kusx1BQ4h_10rustc_span6def_id10LocalDefIdRSB1d_NCINvMs1_NtNtCs81DRtryM8Ze_12rustc_middle3hir3mapNtNtNtB2j_2ty7context6TyCtxt19par_hir_body_ownersNCNvCs43P3SMvJBZA_18rustc_
  37:     0x7ff9143b1f58 - rustc_hir_analysis[2f4f0d01f4da5d08]::check_crate
  38:     0x7ff90f6cea39 - rustc_interface[12828e12a73e27df]::passes::analysis
  39:     0x7ff916950113 - rustc_query_impl[636a45210f4627b1]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[636a45210f4627b1]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[5d7d5661cb7251f6]::query::erase::Erased<[u8; 0usize]>>
  40:     0x7ff916894394 - rustc_query_impl[636a45210f4627b1]::query_impl::items_of_instance::get_query_incr::__rust_end_short_backtrace
  41:     0x7ff9166eb074 - RINvNtNtCskdyPo4XOC2c_18rustc_query_system5query8plumbing17try_execute_queryINtCs8xbqABPlkTB_16rustc_query_impl13DynamicConfigINtNtB4_6caches11SingleCacheINtNtNtCs81DRtryM8Ze_12rustc_middle5query5erase6ErasedAhj0_EEKb0_KB3s_KB3s_ENtNtB1f_8plumbing9QueryCtx
  42:     0x7ff9169aa1ee - rustc_query_impl[636a45210f4627b1]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  43:     0x7ff90f3842c0 - RINvMs2_NtNtCsdtfb8v2o8zK_3std6thread5localINtB6_8LocalKeyINtNtCs5ASmzjaxJJ1_4core4cell4CellPuEE4withNCINvNtNtNtCs81DRtryM8Ze_12rustc_middle2ty7context3tls13enter_contextNCINvMsj_B1I_NtB1I_10GlobalCtxt5enterNCNCINvNtCs1AwKmJrtcJv_15rustc_interface6passes28
  44:     0x7ff90f402e0a - RINvMsn_NtNtCs81DRtryM8Ze_12rustc_middle2ty7contextNtB6_6TyCtxt18create_global_ctxtINtNtCs5ASmzjaxJJ1_4core6option6OptionNtNtCs1AwKmJrtcJv_15rustc_interface7queries6LinkerENCNCINvNtB1Z_6passes28create_and_enter_global_ctxtB1j_NCNCNvCs59evyLnHgro_17rustc_dr
  45:     0x7ff90f44ce9f - RINvNtNtNtNtCs5ASmzjaxJJ1_4core5slice4sort6stable5drift4sortTReINtNtCscm7aL0A7JxU_5alloc3vec3VecNtCsgLkGPo3yd2H_15rustc_lint_defs6LintIdEENCINvMNtB14_5sliceSBW_11sort_by_keyBX_NCNvNvCs59evyLnHgro_17rustc_driver_impl14describe_lints16sort_lint_groupss_0E0EB
  46:     0x7ff90f33cdb7 - RNvXsq_NtCscm7aL0A7JxU_5alloc5boxedINtB5_3BoxDG_INtNtNtCs5ASmzjaxJJ1_4core3ops8function6FnOnceTRL0_NtNtCsh65XgmMMbrM_13rustc_session7session7SessionNtNtNtCs81DRtryM8Ze_12rustc_middle2ty7context10CurrentGcxINtNtB7_4sync3ArcNtNtCsaSadm4QJbrx_21rustc_data_str
  47:     0x7ff90f43353c - rustc_interface[12828e12a73e27df]::passes::create_and_enter_global_ctxt::<core[412a7be69771ea95]::option::Option<rustc_interface[12828e12a73e27df]::queries::Linker>, rustc_driver_impl[3bf90c00a8843f1c]::run_compiler::{closure#0}::{closure#2}>
  48:     0x7ff90f3db43e - RINvMs_Csd2ZlngM0Ze5_10scoped_tlsINtB5_9ScopedKeyNtCsl0kusx1BQ4h_10rustc_span14SessionGlobalsE3setNCNCNCINvNtCs1AwKmJrtcJv_15rustc_interface4util26run_in_thread_with_globalsNCINvB1H_31run_in_thread_pool_with_globalsNCINvNtB1J_9interface12run_compileruNCNvC
  49:     0x7ff90f3fac3b - RINvNtNtCsdtfb8v2o8zK_3std3sys9backtrace28___rust_begin_short_backtraceNCNCINvNtCs1AwKmJrtcJv_15rustc_interface4util26run_in_thread_with_globalsNCINvB1e_31run_in_thread_pool_with_globalsNCINvNtB1g_9interface12run_compileruNCNvCs59evyLnHgro_17rustc_driver_i
  50:     0x7ff90f3fbe1a - <std[9ce9c1f2dc40b5ca]::path::PathBuf as core[412a7be69771ea95]::hash::Hash>::hash::<rustc_stable_hash[5641361ce2aabf25]::stable_hasher::StableHasher<rustc_stable_hash[5641361ce2aabf25]::sip128::SipHasher128>>
  51:     0x7ff9188b32c8 - std::sys::pal::windows::thread::Thread::new::h13edd82b9f2c9955
  52:     0x7ff96d72e8d7 - BaseThreadInitThunk
  53:     0x7ff96e95c34c - RtlUserThreadStart

error: the compiler unexpectedly panicked. this is a bug.
---

note: compiler flags: -Z treat-err-as-bug=1

query stack during panic:
#0 [typeck] type-checking `main`
#1 [analysis] running analysis passes on this crate
end of query stack

  left: 3
 right: 5
---
test result: FAILED. 311 passed; 1 failed; 86 ignored; 0 measured; 6 filtered out; finished in 219.70s

Some tests failed in compiletest suite=run-make mode=run-make host=x86_64-pc-windows-msvc target=x86_64-pc-windows-msvc
Build completed unsuccessfully in 2:19:17
make: *** [Makefile:112: ci-msvc-py] Error 1
  local time: Mon Jun 30 01:44:51 CUT 2025
  network time: Mon, 30 Jun 2025 01:44:51 GMT
##[error]Process completed with exit code 2.
Post job cleanup.
[command]"C:\Program Files\Git\bin\git.exe" version

bors · 2025-06-30T01:45:40Z

💔 Test failed - checks-actions

compiler-errors · 2025-06-30T01:47:27Z

spurious?

@bors retry

bors · 2025-06-30T02:02:49Z

⌛ Testing commit 0d37587 with merge f191420...

bors · 2025-06-30T05:02:20Z

☀️ Test successful - checks-actions
Approved by: lcnr
Pushing f191420 to master...

github-actions · 2025-06-30T05:05:19Z

What is this?

This is an experimental post-merge analysis report that shows differences in test outcomes between the merged PR and its parent PR.

Comparing 35f6036 (parent) -> f191420 (this PR)

Test differences

Show 2 test diffs

2 doctest diffs were found. These are ignored, as they are noisy.

Test dashboard

Run

cargo run --manifest-path src/ci/citool/Cargo.toml -- \
    test-dashboard f19142044f270760ce0ebc03b2c3a44217d8703d --output-dir test-dashboard

And then open test-dashboard/index.html in your browser to see an overview of all executed tests.

Job duration changes

dist-aarch64-linux: 7897.9s -> 5391.2s (-31.7%)
x86_64-apple-2: 5157.9s -> 3935.1s (-23.7%)
dist-apple-various: 6268.9s -> 5248.9s (-16.3%)
dist-aarch64-apple: 4742.3s -> 5479.6s (15.5%)
dist-x86_64-apple: 7744.9s -> 8932.5s (15.3%)
x86_64-apple-1: 7425.1s -> 6599.9s (-11.1%)
dist-powerpc64le-linux-musl: 4898.5s -> 5168.5s (5.5%)
dist-x86_64-mingw: 8283.5s -> 7840.3s (-5.4%)
aarch64-gnu-debug: 4120.7s -> 3922.8s (-4.8%)
dist-various-2: 3253.5s -> 3100.4s (-4.7%)

How to interpret the job duration changes?

Job durations can vary a lot, based on the actual runner instance
that executed the job, system noise, invalidated caches, etc. The table above is provided
mostly for t-infra members, for simpler debugging of potential CI slow-downs.

rust-timer · 2025-06-30T06:27:20Z

Finished benchmarking commit (f191420): comparison URL.

Overall result: ✅ improvements - no action needed

@rustbot label: -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
Regressions ❌ (secondary)	0.8%	[0.8%, 0.8%]	1
Improvements ✅ (primary)	-0.8%	[-4.6%, -0.2%]	84
Improvements ✅ (secondary)	-5.6%	[-21.6%, -0.1%]	71
All ❌✅ (primary)	-0.8%	[-4.6%, -0.2%]	84

Max RSS (memory usage)

Results (secondary -3.3%)

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)	2.9%	[1.5%, 4.2%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-5.1%	[-8.6%, -0.9%]	7
All ❌✅ (primary)	-	-	0

Cycles

Results (primary -2.0%, secondary -12.4%)

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)	-	-	0
Improvements ✅ (primary)	-2.0%	[-3.7%, -0.9%]	16
Improvements ✅ (secondary)	-12.4%	[-27.0%, -1.5%]	35
All ❌✅ (primary)	-2.0%	[-3.7%, -0.9%]	16

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 695.714s -> 695.172s (-0.08%)
Artifact size: 371.68 MiB -> 372.16 MiB (0.13%)

rustbot added the T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. label Jun 24, 2025

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Auto merge of #142941 - compiler-errors:shallow-bail, r=<try>

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[perf] Shallowly bail from `coerce_unsized` more

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rustbot removed the S-waiting-on-perf Status: Waiting on a perf run to be completed. label Jun 24, 2025

compiler-errors force-pushed the shallow-bail branch from e0b68fe to 3d115ac Compare June 24, 2025 16:52

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rust-bors bot added a commit that referenced this pull request Jun 24, 2025

Auto merge of #142941 - compiler-errors:shallow-bail, r=<try>

1eb1a24

[perf] Shallowly bail from `coerce_unsized` more

rustbot added the S-waiting-on-perf Status: Waiting on a perf run to be completed. label Jun 24, 2025

compiler-errors marked this pull request as ready for review June 24, 2025 17:01

rustbot assigned petrochenkov Jun 24, 2025

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rustbot assigned lcnr and unassigned petrochenkov Jun 24, 2025

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compiler-errors changed the title ~~[perf] Shallowly bail from coerce_unsized more~~ Shallowly bail from coerce_unsized more Jun 24, 2025

rustbot removed the S-waiting-on-perf Status: Waiting on a perf run to be completed. label Jun 25, 2025

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compiler-errors added 3 commits June 26, 2025 15:52

Assert shallow resolved args in coerce

8242b55

Shallowly bail from coerce_unsized more

904458f

Add a note and one more fast path

0d37587

compiler-errors force-pushed the shallow-bail branch from 3d115ac to 0d37587 Compare June 26, 2025 15:56

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 Jun 26, 2025

bors added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. labels Jun 30, 2025

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 Jun 30, 2025

bors added the merged-by-bors This PR was explicitly merged by bors. label Jun 30, 2025

bors merged commit f191420 into rust-lang:master Jun 30, 2025
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rustbot added this to the 1.90.0 milestone Jun 30, 2025

Shallowly bail from coerce_unsized more #142941

Shallowly bail from coerce_unsized more #142941

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rust-timer commented Jun 24, 2025

Overall result: ✅ improvements - no action needed

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Overall result: ✅ improvements - no action needed

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lcnr commented Jun 26, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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github-actions bot commented Jun 30, 2025

Test differences

Job duration changes

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rust-timer commented Jun 30, 2025

Shallowly bail from `coerce_unsized` more #142941

Shallowly bail from `coerce_unsized` more #142941

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