Skip to content

add core test run with -Zforce-intrinsic-fallback#158927

Merged
rust-bors[bot] merged 1 commit into
rust-lang:mainfrom
folkertdev:test-fallback-bodies
Jul 9, 2026
Merged

add core test run with -Zforce-intrinsic-fallback#158927
rust-bors[bot] merged 1 commit into
rust-lang:mainfrom
folkertdev:test-fallback-bodies

Conversation

@folkertdev

@folkertdev folkertdev commented Jul 7, 2026

Copy link
Copy Markdown
Contributor

Some discussion at #t-infra > CI for -Zforce-intrinsic-fallback.

In #158377 we added -Zforce-intrinsic-fallback which will use an intrinsic's fallback body if there is one.

I'm basing this on #125011, but for now only run the core tests which I think should be sufficient? But maybe I'm missing something, or maybe the alloc/std tests are fast enough that we might as well run them.

One concern I have is how clearly it is reported that the optimize_for_size or -Zforce-intrinsic-fallback runs fail. Because in those cases the standard run succeeded, and so if you miss that an extra flag was passed that can waste a lot of debugging time.

r? Kobzol

@rustbot rustbot added A-CI Area: Our Github Actions CI A-testsuite Area: The testsuite used to check the correctness of rustc S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-infra Relevant to the infrastructure team, which will review and decide on the PR/issue. labels Jul 7, 2026
@rustbot

rustbot commented Jul 7, 2026

Copy link
Copy Markdown
Collaborator

Kobzol is not on the review rotation at the moment.
They may take a while to respond.

@folkertdev

folkertdev commented Jul 7, 2026

Copy link
Copy Markdown
Contributor Author

cc @RalfJung

@Kobzol

Kobzol commented Jul 8, 2026

Copy link
Copy Markdown
Member

One concern I have is how clearly it is reported that the optimize_for_size or -Zforce-intrinsic-fallback runs fail. Because in those cases the standard run succeeded, and so if you miss that an extra flag was passed that can waste a lot of debugging time.

It is a concern, I agree, but bootstrap does actually print the cmdline that it was executing if it fails, and the flag should be visible in the cmdline. We could make that output be more.. screaming :) if need be.

The change is fine by me, you can r=me.

@folkertdev

folkertdev commented Jul 8, 2026

Copy link
Copy Markdown
Contributor Author

Well apparently it's not caused issues before (neither optimize for size nor the miri version of the fallback flag) so it's probably fine for now.

@bors r+

@rust-bors

rust-bors Bot commented Jul 8, 2026

Copy link
Copy Markdown
Contributor

📌 Commit 24fb2fb has been approved by folkertdev

It is now in the queue for this repository.

@rust-bors 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 8, 2026
GuillaumeGomez added a commit to GuillaumeGomez/rust that referenced this pull request Jul 8, 2026
@GuillaumeGomez
Rollup merge of rust-lang#158927 - folkertdev:test-fallback-bodies, r…
7c299d7 
…=folkertdev

add core test run with `-Zforce-intrinsic-fallback`

Some discussion at [#t-infra > CI for -Zforce-intrinsic-fallback](https://rust-lang.zulipchat.com/#narrow/channel/242791-t-infra/topic/CI.20for.20-Zforce-intrinsic-fallback/with/608129693).

In rust-lang#158377 we added `-Zforce-intrinsic-fallback` which will use an intrinsic's fallback body if there is one.

I'm basing this on rust-lang#125011, but for now only run the core tests which I think should be sufficient? But maybe I'm missing something, or maybe the alloc/std tests are fast enough that we might as well run them.

One concern I have is how clearly it is reported that the `optimize_for_size` or `-Zforce-intrinsic-fallback` runs fail. Because in those cases the standard run succeeded, and so if you miss that an extra flag was passed that can waste a lot of debugging time.

r? Kobzol
@GuillaumeGomez GuillaumeGomez mentioned this pull request Jul 8, 2026
Closed
JonathanBrouwer added a commit to JonathanBrouwer/rust that referenced this pull request Jul 8, 2026
@JonathanBrouwer
Rollup merge of rust-lang#158927 - folkertdev:test-fallback-bodies, r…
3d24385 
…=folkertdev

add core test run with `-Zforce-intrinsic-fallback`

Some discussion at [#t-infra > CI for -Zforce-intrinsic-fallback](https://rust-lang.zulipchat.com/#narrow/channel/242791-t-infra/topic/CI.20for.20-Zforce-intrinsic-fallback/with/608129693).

In rust-lang#158377 we added `-Zforce-intrinsic-fallback` which will use an intrinsic's fallback body if there is one.

I'm basing this on rust-lang#125011, but for now only run the core tests which I think should be sufficient? But maybe I'm missing something, or maybe the alloc/std tests are fast enough that we might as well run them.

One concern I have is how clearly it is reported that the `optimize_for_size` or `-Zforce-intrinsic-fallback` runs fail. Because in those cases the standard run succeeded, and so if you miss that an extra flag was passed that can waste a lot of debugging time.

r? Kobzol
@JonathanBrouwer JonathanBrouwer mentioned this pull request Jul 8, 2026
Closed
rust-bors Bot pushed a commit that referenced this pull request Jul 8, 2026
@bors
Auto merge of #158958 - JonathanBrouwer:rollup-jBryWjn, r=JonathanBro…
bd8a819 
…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)
rust-bors Bot pushed a commit that referenced this pull request Jul 8, 2026
@bors
Auto merge of #158958 - JonathanBrouwer:rollup-jBryWjn, r=JonathanBro…
a02d326 
…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)
rust-bors Bot pushed a commit that referenced this pull request Jul 8, 2026
@bors
Auto merge of #158958 - JonathanBrouwer:rollup-jBryWjn, r=JonathanBro…
b4ae8d4 
…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)
JonathanBrouwer added a commit to JonathanBrouwer/rust that referenced this pull request Jul 8, 2026
@JonathanBrouwer
Rollup merge of rust-lang#158927 - folkertdev:test-fallback-bodies, r…
d1e3437 
…=folkertdev

add core test run with `-Zforce-intrinsic-fallback`

Some discussion at [#t-infra > CI for -Zforce-intrinsic-fallback](https://rust-lang.zulipchat.com/#narrow/channel/242791-t-infra/topic/CI.20for.20-Zforce-intrinsic-fallback/with/608129693).

In rust-lang#158377 we added `-Zforce-intrinsic-fallback` which will use an intrinsic's fallback body if there is one.

I'm basing this on rust-lang#125011, but for now only run the core tests which I think should be sufficient? But maybe I'm missing something, or maybe the alloc/std tests are fast enough that we might as well run them.

One concern I have is how clearly it is reported that the `optimize_for_size` or `-Zforce-intrinsic-fallback` runs fail. Because in those cases the standard run succeeded, and so if you miss that an extra flag was passed that can waste a lot of debugging time.

r? Kobzol
@JonathanBrouwer JonathanBrouwer mentioned this pull request Jul 8, 2026
Closed
@folkertdev folkertdev mentioned this pull request Jul 8, 2026
Open
JonathanBrouwer added a commit to JonathanBrouwer/rust that referenced this pull request Jul 8, 2026
@JonathanBrouwer
Rollup merge of rust-lang#158927 - folkertdev:test-fallback-bodies, r…
e3d5c6d 
…=folkertdev

add core test run with `-Zforce-intrinsic-fallback`

Some discussion at [#t-infra > CI for -Zforce-intrinsic-fallback](https://rust-lang.zulipchat.com/#narrow/channel/242791-t-infra/topic/CI.20for.20-Zforce-intrinsic-fallback/with/608129693).

In rust-lang#158377 we added `-Zforce-intrinsic-fallback` which will use an intrinsic's fallback body if there is one.

I'm basing this on rust-lang#125011, but for now only run the core tests which I think should be sufficient? But maybe I'm missing something, or maybe the alloc/std tests are fast enough that we might as well run them.

One concern I have is how clearly it is reported that the `optimize_for_size` or `-Zforce-intrinsic-fallback` runs fail. Because in those cases the standard run succeeded, and so if you miss that an extra flag was passed that can waste a lot of debugging time.

r? Kobzol
@JonathanBrouwer JonathanBrouwer mentioned this pull request Jul 8, 2026
Closed
rust-bors Bot pushed a commit that referenced this pull request Jul 8, 2026
@bors
Auto merge of #158977 - JonathanBrouwer:rollup-Rg07RhL, r=JonathanBro…
1bf22f7 
…uwer

Rollup of 25 pull requests

Successful merges:

 - #158871 (add relnotes for 1.97.0)
 - #158968 (stdarch subtree update)
 - #154445 (rustdoc: Represent `--output-format=json` coverage and ir differently)
 - #156370 (Reject linked dylib EII default overrides)
 - #157153 (allow `Allocator`s to be used as `#[global_allocator]`s)
 - #158495 (Rename HAS_CT_PROJECTION to HAS_CONST_ALIAS)
 - #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`)
 - #158912 (Introduce new bootstrap config section for PGO configuration)
 - #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`)
 - #158932 (Do not build the compiler when invoking `x perf compare`)
 - #158937 (Emit the emscripten entry point as `__main_argc_argv`)
 - #151379 (Stabilize `VecDeque::retain_back` from `truncate_front`)
 - #156548 ( Library support for aarch64-unknown-linux-pauthtest target)
 - #158307 (CI job for parallel frontend ui tests)
 - #158347 (Improve generic parameters handling for #[diagnostic::on_const])
 - #158722 (delegation: do not always inherit `ConstArgHasType` predicates)
 - #158741 (Simplify `Option::into_flat_iter` signature)
 - #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)
jhpratt added a commit to jhpratt/rust that referenced this pull request Jul 8, 2026
@jhpratt
Rollup merge of rust-lang#158927 - folkertdev:test-fallback-bodies, r…
71baa06 
…=folkertdev

add core test run with `-Zforce-intrinsic-fallback`

Some discussion at [#t-infra > CI for -Zforce-intrinsic-fallback](https://rust-lang.zulipchat.com/#narrow/channel/242791-t-infra/topic/CI.20for.20-Zforce-intrinsic-fallback/with/608129693).

In rust-lang#158377 we added `-Zforce-intrinsic-fallback` which will use an intrinsic's fallback body if there is one.

I'm basing this on rust-lang#125011, but for now only run the core tests which I think should be sufficient? But maybe I'm missing something, or maybe the alloc/std tests are fast enough that we might as well run them.

One concern I have is how clearly it is reported that the `optimize_for_size` or `-Zforce-intrinsic-fallback` runs fail. Because in those cases the standard run succeeded, and so if you miss that an extra flag was passed that can waste a lot of debugging time.

r? Kobzol
@jhpratt jhpratt mentioned this pull request Jul 8, 2026
Closed
rust-bors Bot pushed a commit that referenced this pull request Jul 8, 2026
@bors
Auto merge of #158986 - jhpratt:rollup-l8AsZC3, r=jhpratt
e0a8b8a 
Rollup of 25 pull requests

Successful merges:

 - #158871 (add relnotes for 1.97.0)
 - #158968 (stdarch subtree update)
 - #157690 (codegen_ssa: pack small const aggregates into immediate stores)
 - #158541 (Move `std::io::Write` to `core::io`)
 - #154445 (rustdoc: Represent `--output-format=json` coverage and ir differently)
 - #156370 (Reject linked dylib EII default overrides)
 - #157153 (allow `Allocator`s to be used as `#[global_allocator]`s)
 - #158495 (Rename HAS_CT_PROJECTION to HAS_CONST_ALIAS)
 - #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`)
 - #158870 (std: merge the unix-like io::error modules into one file)
 - #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`)
 - #158932 (Do not build the compiler when invoking `x perf compare`)
 - #158937 (Emit the emscripten entry point as `__main_argc_argv`)
 - #151379 (Stabilize `VecDeque::retain_back` from `truncate_front`)
 - #156144 (Better docs for PartialEq (includes macro rename))
 - #156548 ( Library support for aarch64-unknown-linux-pauthtest target)
 - #158307 (CI job for parallel frontend ui tests)
 - #158347 (Improve generic parameters handling for #[diagnostic::on_const])
 - #158722 (delegation: do not always inherit `ConstArgHasType` predicates)
 - #158741 (Simplify `Option::into_flat_iter` signature)
jhpratt added a commit to jhpratt/rust that referenced this pull request Jul 9, 2026
@jhpratt
Rollup merge of rust-lang#158927 - folkertdev:test-fallback-bodies, r…
498316c 
…=folkertdev

add core test run with `-Zforce-intrinsic-fallback`

Some discussion at [#t-infra > CI for -Zforce-intrinsic-fallback](https://rust-lang.zulipchat.com/#narrow/channel/242791-t-infra/topic/CI.20for.20-Zforce-intrinsic-fallback/with/608129693).

In rust-lang#158377 we added `-Zforce-intrinsic-fallback` which will use an intrinsic's fallback body if there is one.

I'm basing this on rust-lang#125011, but for now only run the core tests which I think should be sufficient? But maybe I'm missing something, or maybe the alloc/std tests are fast enough that we might as well run them.

One concern I have is how clearly it is reported that the `optimize_for_size` or `-Zforce-intrinsic-fallback` runs fail. Because in those cases the standard run succeeded, and so if you miss that an extra flag was passed that can waste a lot of debugging time.

r? Kobzol
This was referenced Jul 9, 2026
Closed
Merged
rust-bors Bot pushed a commit that referenced this pull request Jul 9, 2026
@bors
Auto merge of #158991 - jhpratt:rollup-dpRq53N, r=jhpratt
561ea2b 
Rollup of 23 pull requests

Successful merges:

 - #158968 (stdarch subtree update)
 - #154445 (rustdoc: Represent `--output-format=json` coverage and ir differently)
 - #158495 (Rename HAS_CT_PROJECTION to HAS_CONST_ALIAS)
 - #158666 (Carry the `b_offset` inside `BackendRepr::ScalarPair`)
 - #158870 (std: merge the unix-like io::error modules into one file)
 - #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`)
 - #158932 (Do not build the compiler when invoking `x perf compare`)
 - #158937 (Emit the emscripten entry point as `__main_argc_argv`)
 - #151379 (Stabilize `VecDeque::retain_back` from `truncate_front`)
 - #156144 (Better docs for PartialEq (includes macro rename))
 - #156548 ( Library support for aarch64-unknown-linux-pauthtest target)
 - #157995 (`Vec::dedup_by` docs explicit function argument order)
 - #158307 (CI job for parallel frontend ui tests)
 - #158741 (Simplify `Option::into_flat_iter` signature)
 - #158807 (Add regression test for CString::clone_into unwind safety)
 - #158862 (Fix the span for parameter suggestion )
 - #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)
 - #158978 (Add regression test for too-big by-value ABI args)
@rust-bors rust-bors Bot merged commit f9f0989 into rust-lang:main Jul 9, 2026
13 checks passed
@rustbot rustbot added this to the 1.99.0 milestone Jul 9, 2026
rust-timer added a commit that referenced this pull request Jul 9, 2026
@rust-timer
Unrolled build for #158927
4bf450a 
Rollup merge of #158927 - folkertdev:test-fallback-bodies, r=folkertdev

add core test run with `-Zforce-intrinsic-fallback`

Some discussion at [#t-infra > CI for -Zforce-intrinsic-fallback](https://rust-lang.zulipchat.com/#narrow/channel/242791-t-infra/topic/CI.20for.20-Zforce-intrinsic-fallback/with/608129693).

In #158377 we added `-Zforce-intrinsic-fallback` which will use an intrinsic's fallback body if there is one.

I'm basing this on #125011, but for now only run the core tests which I think should be sufficient? But maybe I'm missing something, or maybe the alloc/std tests are fast enough that we might as well run them.

One concern I have is how clearly it is reported that the `optimize_for_size` or `-Zforce-intrinsic-fallback` runs fail. Because in those cases the standard run succeeded, and so if you miss that an extra flag was passed that can waste a lot of debugging time.

r? Kobzol
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

No reviews

Assignees

@Kobzol Kobzol

Labels

A-CI Area: Our Github Actions CI A-testsuite Area: The testsuite used to check the correctness of rustc S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. T-infra Relevant to the infrastructure team, which will review and decide on the PR/issue.

Projects

None yet

Milestone

1.99.0

Development

Successfully merging this pull request may close these issues.

3 participants

@folkertdev @rustbot @Kobzol