[TOY] Run MIR opts before coroutine state transform #145330

cjgillot · 2025-08-13T02:07:22Z

cjgillot · 2025-08-13T18:54:41Z

[TOY] Run MIR opts before coroutine state transform

rust-bors · 2025-08-13T21:07:31Z

☀️ Try build successful (CI)
Build commit: b6ae10a (b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b, parent: 350d0ef0ec0493e6d21cfb265cb8211a0e74d766)

cjgillot · 2025-08-13T21:35:16Z

@rust-timer queue

lqd · 2025-08-13T22:14:26Z

@rust-timer build b6ae10a

rust-timer · 2025-08-13T23:31:24Z

Finished benchmarking commit (b6ae10a): comparison URL.

Overall result: ❌✅ regressions and improvements - please read the text below

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.

Next Steps: If you can justify the regressions found in this try perf run, please do so in sufficient writing along with @rustbot label: +perf-regression-triaged. If not, please fix the regressions and do another perf run. If its results are neutral or positive, the label will be automatically removed.

@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%, 0.3%]	3
Regressions ❌ (secondary)	3.0%	[0.5%, 8.5%]	8
Improvements ✅ (primary)	-0.3%	[-1.2%, -0.1%]	11
Improvements ✅ (secondary)	-1.6%	[-4.4%, -0.2%]	16
All ❌✅ (primary)	-0.2%	[-1.2%, 0.3%]	14

Max RSS (memory usage)

Results (primary -2.4%, secondary 0.7%)

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

	mean	range	count
Regressions ❌ (primary)	1.0%	[0.9%, 1.1%]	2
Regressions ❌ (secondary)	2.3%	[1.5%, 2.9%]	4
Improvements ✅ (primary)	-9.2%	[-9.2%, -9.2%]	1
Improvements ✅ (secondary)	-2.5%	[-2.5%, -2.4%]	2
All ❌✅ (primary)	-2.4%	[-9.2%, 1.1%]	3

Cycles

Results (secondary -0.6%)

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)	4.1%	[2.0%, 5.3%]	3
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-2.9%	[-4.1%, -1.6%]	6
All ❌✅ (primary)	-	-	0

Binary size

Results (primary 0.0%, secondary 2.9%)

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

	mean	range	count
Regressions ❌ (primary)	0.1%	[0.1%, 0.1%]	4
Regressions ❌ (secondary)	6.4%	[0.1%, 18.3%]	18
Improvements ✅ (primary)	-0.0%	[-0.0%, -0.0%]	6
Improvements ✅ (secondary)	-0.4%	[-6.3%, -0.0%]	19
All ❌✅ (primary)	0.0%	[-0.0%, 0.1%]	10

Bootstrap: 468.291s -> 467.628s (-0.14%)
Artifact size: 377.36 MiB -> 377.38 MiB (0.00%)

bors · 2025-08-20T00:22:22Z

☔ The latest upstream changes (presumably #145600) made this pull request unmergeable. Please resolve the merge conflicts.

bors · 2025-08-27T10:31:55Z

☔ The latest upstream changes (presumably #145916) made this pull request unmergeable. Please resolve the merge conflicts.

bors · 2025-09-17T11:48:49Z

☔ The latest upstream changes (presumably #146666) made this pull request unmergeable. Please resolve the merge conflicts.

cjgillot · 2025-09-21T20:03:24Z

Let's try to discover miscompilations:
@craterbot run mode=build-and-test

craterbot · 2025-09-21T20:03:41Z

👌 Experiment pr-145330 created and queued.
🤖 Automatically detected try build b6ae10a
⚠️ Try build based on commit 0be736b, but latest commit is 5c25cff. Did you forget to make a new try build?
🔍 You can check out the queue and this experiment's details.

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

craterbot · 2025-09-21T20:04:42Z

🚧 Experiment pr-145330 is now running

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

craterbot · 2025-09-23T12:56:54Z

🎉 Experiment pr-145330 is completed!
📊 255 regressed and 166 fixed (703555 total)
📊 119132 spurious results on the retry-regessed-list.txt, consider a retry¹ if this is a significant amount.
📰 Open the summary report.

⚠️ If you notice any spurious failure please add them to the denylist!
ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

re-run the experiment with crates=https://crater-reports.s3.amazonaws.com/pr-145330/retry-regressed-list.txt ↩

cjgillot · 2025-09-26T00:21:42Z

@craterbot run mode=build-and-test crates=https://crater-reports.s3.amazonaws.com/pr-145330/retry-regressed-list.txt

cjgillot · 2025-09-26T21:15:13Z

@craterbot run mode=build-and-test crates=https://crater-reports.s3.amazonaws.com/pr-145330/retry-regressed-list.txt

craterbot · 2025-09-26T21:15:25Z

👌 Experiment pr-145330-1 created and queued.
🤖 Automatically detected try build b6ae10a
⚠️ Try build based on commit 0be736b, but latest commit is 5c25cff. Did you forget to make a new try build?
🔍 You can check out the queue and this experiment's details.

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

craterbot · 2025-10-02T00:29:41Z

🚧 Experiment pr-145330-1 is now running

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

craterbot · 2025-10-02T12:11:17Z

🎉 Experiment pr-145330-1 is completed!
📊 210 regressed and 124 fixed (119308 total)
📊 587 spurious results on the retry-regessed-list.txt, consider a retry¹ if this is a significant amount.
📰 Open the summary report.

⚠️ If you notice any spurious failure please add them to the denylist!
ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

re-run the experiment with crates=https://crater-reports.s3.amazonaws.com/pr-145330-1/retry-regressed-list.txt ↩

bors · 2025-10-03T16:01:23Z

☔ The latest upstream changes (presumably #142771) made this pull request unmergeable. Please resolve the merge conflicts.

rust-log-analyzer · 2025-10-04T17:30:41Z

The job aarch64-gnu-llvm-20-1 failed! Check out the build log: (web) (plain enhanced) (plain)

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

test [crashes] tests/crashes/140123-3.rs ... ok
test [crashes] tests/crashes/140123-4.rs ... ok
test [crashes] tests/crashes/140123.rs ... ok
test [crashes] tests/crashes/140275.rs ... ok
2025-10-04T17:30:26.084053Z ERROR compiletest::runtest: fatal error, panic: "crashtest no longer crashes/triggers ICE, hooray! Please give it a meaningful name, add a doc-comment to the start of the test explaining why it exists and move it to tests/ui or wherever you see fit. Adding 'Fixes #<issueNr>' to your PR description ensures that the corresponding ticket is auto-closed upon merge. If you want to see verbose output, set `COMPILETEST_VERBOSE_CRASHES=1`."
test [crashes] tests/crashes/140381.rs ... ok
test [crashes] tests/crashes/140303.rs ... FAILED
test [crashes] tests/crashes/140577.rs ... ok
test [crashes] tests/crashes/140609.rs ... ok
test [crashes] tests/crashes/140729.rs ... ok
---

---- [crashes] tests/crashes/140303.rs stdout ----
------rustc stdout------------------------------

------rustc stderr------------------------------
error[E0670]: `async fn` is not permitted in Rust 2015
##[error] --> /checkout/tests/crashes/140303.rs:4:1
  |
4 | async fn a() -> impl Sized {
  | ^^^^^ to use `async fn`, switch to Rust 2018 or later
  |
  = help: pass `--edition 2024` to `rustc`
  = note: for more on editions, read https://doc.rust-lang.org/edition-guide

error[E0670]: `async fn` is not permitted in Rust 2015
##[error] --> /checkout/tests/crashes/140303.rs:7:1
  |
7 | async fn c(); // kaboom
  | ^^^^^ to use `async fn`, switch to Rust 2018 or later
  |
  = help: pass `--edition 2024` to `rustc`
  = note: for more on editions, read https://doc.rust-lang.org/edition-guide

error: free function without a body
##[error] --> /checkout/tests/crashes/140303.rs:7:1
  |
7 | async fn c(); // kaboom
  | ^^^^^^^^^^^^-
  |             |
  |             help: provide a definition for the function: `{ <body> }`

warning: type parameter `d` should have an upper camel case name
##[warning] --> /checkout/tests/crashes/140303.rs:8:6
  |
8 | fn b<d>(e: d) -> impl Sized
  |      ^ help: convert the identifier to upper camel case: `D`
  |
  = note: `#[warn(non_camel_case_types)]` (part of `#[warn(nonstandard_style)]`) on by default

warning: trait `f` should have an upper camel case name
##[warning]  --> /checkout/tests/crashes/140303.rs:14:7
   |
14 | trait f {
   |       ^ help: convert the identifier to upper camel case (notice the capitalization): `F`

warning: associated type `h` should have an upper camel case name
##[warning]  --> /checkout/tests/crashes/140303.rs:15:10
   |
15 |     type h;
   |          ^ help: convert the identifier to upper camel case: `H`

warning: type parameter `d` should have an upper camel case name
##[warning]  --> /checkout/tests/crashes/140303.rs:17:6
   |
17 | impl<d, g> f for d
   |      ^ help: convert the identifier to upper camel case: `D`

warning: type parameter `g` should have an upper camel case name
##[warning]  --> /checkout/tests/crashes/140303.rs:17:9
   |
17 | impl<d, g> f for d
   |         ^ help: convert the identifier to upper camel case: `G`

error[E0601]: `main` function not found in crate `140303`
##[error]  --> /checkout/tests/crashes/140303.rs:22:2
   |
22 | }
---
   |
15 |       type h;
   |       ------ `h` from trait
16 |   }
17 | / impl<d, g> f for d
18 | | where
19 | |     d: Fn() -> g,
20 | |     g: Future,
   | |______________^ missing `h` in implementation

warning: unused variable: `e`
##[warning] --> /checkout/tests/crashes/140303.rs:8:9
  |
8 | fn b<d>(e: d) -> impl Sized
  |         ^ help: if this is intentional, prefix it with an underscore: `_e`
  |
  = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default

error: aborting due to 5 previous errors; 6 warnings emitted

Some errors have detailed explanations: E0046, E0601, E0670.
For more information about an error, try `rustc --explain E0046`.

------------------------------------------

error: crashtest no longer crashes/triggers ICE, hooray! Please give it a meaningful name, add a doc-comment to the start of the test explaining why it exists and move it to tests/ui or wherever you see fit. Adding 'Fixes #<issueNr>' to your PR description ensures that the corresponding ticket is auto-closed upon merge. If you want to see verbose output, set `COMPILETEST_VERBOSE_CRASHES=1`.

thread '[crashes] tests/crashes/140303.rs' panicked at src/tools/compiletest/src/runtest/crashes.rs:17:18:
fatal error
stack backtrace:
   5: __rustc::rust_begin_unwind

dingxiangfei2009 · 2025-10-06T13:45:18Z

compiler/rustc_mir_transform/src/coroutine.rs

-    new_local
+    let source_info = SourceInfo::outermost(body.span);
+    body.basic_blocks_mut()[START_BLOCK].statements.insert(
+        0,


Oh we probably should make sure that Retag happens first. Otherwise, MIRI will complain.

bors · 2025-10-07T18:37:19Z

☔ The latest upstream changes (presumably #145608) made this pull request unmergeable. Please resolve the merge conflicts.

rustbot added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Aug 13, 2025

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cjgillot force-pushed the optimized-generator branch from 08f1ddf to 0be736b Compare August 13, 2025 02:16