Test: Ambigious bindings in same namespace with the same res

[LorrensP-2158466]

Add a test based on the discussion here and related to #145575 (comment).

This is the most reduced form I could create that passes on nightly but fails with #145108 (see #gsoc > Project: Parallel Macro Expansion @ 💬).

Also not sure about the test names.

r? @petrochenkov

[petrochenkov]

This is the most reduced form I could create that passes on nightly

I mostly wanted a version of the same issue that fails on nightly, but having both would be even better.

[LorrensP-2158466]

Added a revision that uses the version where the glob import is inserted by a macro. I have confirmed this fails when using cargo +stage1 check on my own crates, but for some reason, this is not working in ui tests. I'm probably doing something wrong, but I can't figure it out from the docs.

[LorrensP-2158466]

@rustbot ready

I'm still confused why the nightly-fail doesn't fail in the tests but fails when I extract them into their own separate crates and compile them myself.

[petrochenkov]

@rustbot ready

I'm still confused why the nightly-fail doesn't fail in the tests but fails when I extract them into their own separate crates and compile them myself.

Need to figure this out, split the test if necessary.
@rustbot author

[rustbot]

Reminder, once the PR becomes ready for a review, use @rustbot ready.

[petrochenkov]

Default edition may be different in ui tests (2015) and your local setup, it affects import resolution.

[LorrensP-2158466]

Ah, right, editions. I set them up correctly based on the output I get on my local setup with cargo +stage1 build -v. Both crates are compiled with edition 2018, and the pulling crate in 2024. The error is still different, with it now reporting that the macro is private instead of not accessible in the scope.

The only difference I see is that ambiguous_extern is passed as a dylib in the tests and as a .rmeta file in my local setup. I have been trying to understand how to change this, but i have not made any progress.

@rustbot ready

[petrochenkov]

The error is still different, with it now reporting that the macro is private instead of not accessible in the scope.

This version is even better, the issue can be seen more directly.

The only difference I see is that ambiguous_extern is passed as a dylib in the tests and as a .rmeta file in my local setup.

This is not important.

r=me with green CI (stderr files need to be updated) and after squashing commits.

[LorrensP-2158466]

This version is even better, the issue can be seen more directly.

Nice!

r=me with green CI (stderr files need to be updated) and after squashing commits.

You'll have to r+ this :), I don't have those privileges. @rustbot ready

[petrochenkov]

@bors r+

[bors]

📌 Commit a7eed08 has been approved by petrochenkov

It is now in the queue for this repository.

[bors]

⌛ Testing commit a7eed08 with merge 5c7ae0c...

[bors]

☀️ Test successful - checks-actions
Approved by: petrochenkov
Pushing 5c7ae0c to master...

[github-actions]

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 94ecb52 (parent) -> 5c7ae0c (this PR)

Test differences

Show 8 test diffs

Stage 1

• [ui] tests/ui/imports/same-res-ambigious.rs#fail: [missing] -> pass (J0)
• [ui] tests/ui/imports/same-res-ambigious.rs#pass: [missing] -> pass (J0)

Stage 2

• [ui] tests/ui/imports/same-res-ambigious.rs#fail: [missing] -> pass (J1)
• [ui] tests/ui/imports/same-res-ambigious.rs#pass: [missing] -> pass (J1)

Additionally, 4 doctest diffs were found. These are ignored, as they are noisy.

Job group index

• J0: x86_64-gnu-llvm-20-3
• J1: aarch64-apple, aarch64-gnu, aarch64-gnu-llvm-20-1, aarch64-msvc-1, arm-android, armhf-gnu, dist-i586-gnu-i586-i686-musl, i686-gnu-1, i686-gnu-nopt-1, i686-msvc-1, test-various, x86_64-gnu, x86_64-gnu-debug, x86_64-gnu-llvm-20, x86_64-gnu-llvm-20-2, x86_64-gnu-nopt, x86_64-gnu-stable, x86_64-mingw-1, x86_64-msvc-1

Test dashboard

Run

cargo run --manifest-path src/ci/citool/Cargo.toml -- \
    test-dashboard 5c7ae0c7ed184c603e5224604a9f33ca0e8e0b36 --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

1. dist-apple-various: 3655.4s -> 4603.5s (25.9%)
2. dist-x86_64-freebsd: 5028.6s -> 6227.8s (23.8%)
3. x86_64-gnu-distcheck: 7106.5s -> 6188.6s (-12.9%)
4. x86_64-gnu-llvm-20: 2753.5s -> 2406.6s (-12.6%)
5. tidy: 182.1s -> 202.4s (11.1%)
6. i686-gnu-2: 6144.3s -> 5489.7s (-10.7%)
7. aarch64-gnu-llvm-20-2: 2427.3s -> 2169.7s (-10.6%)
8. aarch64-gnu: 6769.6s -> 6060.2s (-10.5%)
9. i686-gnu-nopt-1: 8043.4s -> 7257.2s (-9.8%)
10. dist-aarch64-msvc: 5626.9s -> 6172.1s (9.7%)

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]

Finished benchmarking commit (5c7ae0c): 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
Improvements ✅ (primary)	-2.9%	[-2.9%, -2.9%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-2.9%	[-2.9%, -2.9%]	1

Max RSS (memory usage)

Results (primary 0.8%)

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

	mean	range	count
Regressions ❌ (primary)	0.8%	[0.8%, 0.8%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.8%	[0.8%, 0.8%]	1

Cycles

Results (primary -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)	-	-	0
Improvements ✅ (primary)	-2.6%	[-2.6%, -2.6%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-2.6%	[-2.6%, -2.6%]	1

Binary size

Results (primary -1.1%)

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)	-1.1%	[-1.1%, -1.1%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-1.1%	[-1.1%, -1.1%]	1

Bootstrap: 470.352s -> 471.823s (0.31%)
Artifact size: 387.80 MiB -> 387.78 MiB (-0.00%)