Implement `//@ needs-target-std` compiletest directive #142297

jieyouxu · 2025-06-10T14:33:26Z

Closes #141863.
Needed to unblock #139244 and #141856.

Summary

This PR implements a //@ needs-target-std compiletest directive that gates test execution based on whether the target supports std or not. For some cases, this should be preferred over e.g. some combination of //@ ignore-none, //@ ignore-nvptx and more¹.

Implementation limitation

Unfortunately, since there is currently no reliable way to determine from metadata whether a given target supports std or not, we have to resort to a hack. Bootstrap currently determines whether or not a target supports std by a naive target tuple substring comparison: a target supports std if its target tuple does not contain one of ["-none", "nvptx", "switch"] substrings. This PR simply pulls that hack out into build_helpers to avoid reimplementing the same hack in compiletest, and uses that logic to inform //@ needs-target-std.

Auxiliary changes

This PR additionally changes a few run-make tests to use //@ needs-target-std over an inconsistent combination of target-based ignores. This should help with #139244.

r? bootstrap

Notably, target_os = "none" is not a sufficient condition for "target does not support std" ↩

To centralize this hack in one place with a backlink to the issue tracking this hack, as this logic is also needed by compiletest to implement a `//@ needs-target-std` directive.

To support tests to condition their (potentially cross-compile) execution based on whether the target supports std.

rustbot · 2025-06-10T14:33:35Z

This PR modifies src/bootstrap/src/core/config.

If appropriate, please update CONFIG_CHANGE_HISTORY in src/bootstrap/src/utils/change_tracker.rs.

The rustc-dev-guide subtree was changed. If this PR only touches the dev guide consider submitting a PR directly to rust-lang/rustc-dev-guide otherwise thank you for updating the dev guide with your changes.

cc @BoxyUwU, @jieyouxu, @Kobzol

Kobzol

Looks reasonable.

tests/run-make/cpp-global-destructors/rmake.rs

tests/run-make/export-executable-symbols/rmake.rs

Instead of a jumble of `ignore-$target`s, `ignore-none` and `ignore-nvptx`.

jieyouxu · 2025-06-10T15:32:08Z

Since you're already looking at it, r? Kobzol

Kobzol · 2025-06-10T15:33:31Z

Maybe you could do the usual try build with "annoying CI jobs that cross-compile". Feel free to r=me with or without doing that.

Urgau · 2025-06-10T15:52:14Z

We have some metadata for that inn the Target json input/output.

rust/compiler/rustc_target/src/json.rs

Line 101 in 100199c

"std": self.std,

jieyouxu · 2025-06-10T15:53:02Z

We have some metadata for that inn the Target json input/output.

rust/compiler/rustc_target/src/json.rs

Line 101 in 100199c

"std": self.std,

Please see #142296, I've looked at that avenue already. TL;DR not all built-in target specs have this metadata std field

rustc similarly does not have any way to convey this information. For instance, the closest thing is the target spec metadata.std field, but not all built-in target specs actually populate this field[^intent]. Built-in target specs currently without std support field

(Which additionally, the metadata field is only intended for doc generation purposes, and I don't think we can rely on that as-is even if all target specs do have this metadata available.)

jieyouxu · 2025-06-10T15:53:30Z

@bors2 try jobs=test-various,armhf-gnu

rust-bors · 2025-06-10T15:53:34Z

⌛ Trying commit c558db3 with merge 5a1574d…

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

Implement `//@ needs-target-std` compiletest directive Closes #141863. Needed to unblock #139244 and #141856. ### Summary This PR implements a `//@ needs-target-std` compiletest directive that gates test execution based on whether the target supports std or not. For some cases, this should be preferred over e.g. some combination of `//@ ignore-none`, `//@ ignore-nvptx` and more[^none-limit]. ### Implementation limitation Unfortunately, since there is currently [no reliable way to determine from metadata whether a given target supports std or not](#142296), we have to resort to a hack. Bootstrap currently determines whether or not a target supports std by a naive target tuple substring comparison: a target supports std if its target tuple does *not* contain one of `["-none", "nvptx", "switch"]` substrings. This PR simply pulls that hack out into `build_helpers` to avoid reimplementing the same hack in compiletest, and uses that logic to inform `//@ needs-target-std`. ### Auxiliary changes This PR additionally changes a few run-make tests to use `//@ needs-target-std` over an inconsistent combination of target-based `ignore`s. This should help with #139244. --- r? bootstrap [^none-limit]: Notably, `target_os = "none"` is **not** a sufficient condition for "target does not support std" try-job: test-various try-job: armhf-gnu

jieyouxu · 2025-06-10T16:36:23Z

@rustbot author

rust-bors · 2025-06-10T17:36:58Z

☀️ Try build successful (CI)
Build commit: 5a1574d (5a1574d9d1d5c87041fdcc35c5794fbf60746c7c)

jieyouxu · 2025-06-10T18:18:36Z

@bors r=Kobzol rollup

bors · 2025-06-10T18:18:39Z

📌 Commit c558db3 has been approved by Kobzol

It is now in the queue for this repository.

Implement `//@ needs-target-std` compiletest directive Closes rust-lang#141863. Needed to unblock rust-lang#139244 and rust-lang#141856. ### Summary This PR implements a `//@ needs-target-std` compiletest directive that gates test execution based on whether the target supports std or not. For some cases, this should be preferred over e.g. some combination of `//@ ignore-none`, `//@ ignore-nvptx` and more[^none-limit]. ### Implementation limitation Unfortunately, since there is currently [no reliable way to determine from metadata whether a given target supports std or not](rust-lang#142296), we have to resort to a hack. Bootstrap currently determines whether or not a target supports std by a naive target tuple substring comparison: a target supports std if its target tuple does *not* contain one of `["-none", "nvptx", "switch"]` substrings. This PR simply pulls that hack out into `build_helpers` to avoid reimplementing the same hack in compiletest, and uses that logic to inform `//@ needs-target-std`. ### Auxiliary changes This PR additionally changes a few run-make tests to use `//@ needs-target-std` over an inconsistent combination of target-based `ignore`s. This should help with rust-lang#139244. --- r? bootstrap [^none-limit]: Notably, `target_os = "none"` is **not** a sufficient condition for "target does not support std"

Rollup of 13 pull requests Successful merges: - #128425 (Make `missing_fragment_specifier` an unconditional error) - #141639 (Expose discriminant values in stable_mir) - #141967 (Configure bootstrap backport nominations through triagebot) - #142042 (Make E0621 missing lifetime suggestion verbose) - #142176 (tests: Split dont-shuffle-bswaps along opt-levels and arches) - #142235 (Build rustc with assertions in `dist-alt` jobs) - #142248 (Add supported asm types for LoongArch32) - #142272 (tests: Change ABIs in tests to more future-resilient ones) - #142282 (Only run `citool` tests on the `auto` branch) - #142285 (tests: Do not run afoul of asm.validity.non-exhaustive in input-stats) - #142297 (Implement `//@ needs-target-std` compiletest directive) - #142298 (Make loongarch-none target maintainers more easily pingable) - #142306 (Dont unwrap and re-wrap typing envs) Failed merges: - #141942 (Implement representation options to smir) r? `@ghost` `@rustbot` modify labels: rollup

Implement `//@ needs-target-std` compiletest directive Closes rust-lang#141863. Needed to unblock rust-lang#139244 and rust-lang#141856. ### Summary This PR implements a `//@ needs-target-std` compiletest directive that gates test execution based on whether the target supports std or not. For some cases, this should be preferred over e.g. some combination of `//@ ignore-none`, `//@ ignore-nvptx` and more[^none-limit]. ### Implementation limitation Unfortunately, since there is currently [no reliable way to determine from metadata whether a given target supports std or not](rust-lang#142296), we have to resort to a hack. Bootstrap currently determines whether or not a target supports std by a naive target tuple substring comparison: a target supports std if its target tuple does *not* contain one of `["-none", "nvptx", "switch"]` substrings. This PR simply pulls that hack out into `build_helpers` to avoid reimplementing the same hack in compiletest, and uses that logic to inform `//@ needs-target-std`. ### Auxiliary changes This PR additionally changes a few run-make tests to use `//@ needs-target-std` over an inconsistent combination of target-based `ignore`s. This should help with rust-lang#139244. --- r? bootstrap [^none-limit]: Notably, `target_os = "none"` is **not** a sufficient condition for "target does not support std"

Rollup of 13 pull requests Successful merges: - #134841 (Look at proc-macro attributes when encountering unknown attribute) - #141639 (Expose discriminant values in stable_mir) - #141967 (Configure bootstrap backport nominations through triagebot) - #142042 (Make E0621 missing lifetime suggestion verbose) - #142176 (tests: Split dont-shuffle-bswaps along opt-levels and arches) - #142248 (Add supported asm types for LoongArch32) - #142272 (tests: Change ABIs in tests to more future-resilient ones) - #142282 (Only run `citool` tests on the `auto` branch) - #142297 (Implement `//@ needs-target-std` compiletest directive) - #142298 (Make loongarch-none target maintainers more easily pingable) - #142306 (Dont unwrap and re-wrap typing envs) - #142324 (Remove unneeded `FunctionCx` from some codegen methods) - #142328 (feat: Add `bit_width` for unsigned integer types) r? `@ghost` `@rustbot` modify labels: rollup

Implement `//@ needs-target-std` compiletest directive Closes rust-lang#141863. Needed to unblock rust-lang#139244 and rust-lang#141856. ### Summary This PR implements a `//@ needs-target-std` compiletest directive that gates test execution based on whether the target supports std or not. For some cases, this should be preferred over e.g. some combination of `//@ ignore-none`, `//@ ignore-nvptx` and more[^none-limit]. ### Implementation limitation Unfortunately, since there is currently [no reliable way to determine from metadata whether a given target supports std or not](rust-lang#142296), we have to resort to a hack. Bootstrap currently determines whether or not a target supports std by a naive target tuple substring comparison: a target supports std if its target tuple does *not* contain one of `["-none", "nvptx", "switch"]` substrings. This PR simply pulls that hack out into `build_helpers` to avoid reimplementing the same hack in compiletest, and uses that logic to inform `//@ needs-target-std`. ### Auxiliary changes This PR additionally changes a few run-make tests to use `//@ needs-target-std` over an inconsistent combination of target-based `ignore`s. This should help with rust-lang#139244. --- r? bootstrap [^none-limit]: Notably, `target_os = "none"` is **not** a sufficient condition for "target does not support std"

Rollup of 9 pull requests Successful merges: - #141967 (Configure bootstrap backport nominations through triagebot) - #142042 (Make E0621 missing lifetime suggestion verbose) - #142272 (tests: Change ABIs in tests to more future-resilient ones) - #142282 (Only run `citool` tests on the `auto` branch) - #142297 (Implement `//@ needs-target-std` compiletest directive) - #142298 (Make loongarch-none target maintainers more easily pingable) - #142306 (Dont unwrap and re-wrap typing envs) - #142324 (Remove unneeded `FunctionCx` from some codegen methods) - #142328 (feat: Add `bit_width` for unsigned integer types) Failed merges: - #141639 (Expose discriminant values in stable_mir) r? `@ghost` `@rustbot` modify labels: rollup

Rollup merge of #142297 - jieyouxu:needs-target-std, r=Kobzol Implement `//@ needs-target-std` compiletest directive Closes #141863. Needed to unblock #139244 and #141856. ### Summary This PR implements a `//@ needs-target-std` compiletest directive that gates test execution based on whether the target supports std or not. For some cases, this should be preferred over e.g. some combination of `//@ ignore-none`, `//@ ignore-nvptx` and more[^none-limit]. ### Implementation limitation Unfortunately, since there is currently [no reliable way to determine from metadata whether a given target supports std or not](#142296), we have to resort to a hack. Bootstrap currently determines whether or not a target supports std by a naive target tuple substring comparison: a target supports std if its target tuple does *not* contain one of `["-none", "nvptx", "switch"]` substrings. This PR simply pulls that hack out into `build_helpers` to avoid reimplementing the same hack in compiletest, and uses that logic to inform `//@ needs-target-std`. ### Auxiliary changes This PR additionally changes a few run-make tests to use `//@ needs-target-std` over an inconsistent combination of target-based `ignore`s. This should help with #139244. --- r? bootstrap [^none-limit]: Notably, `target_os = "none"` is **not** a sufficient condition for "target does not support std"

Rollup of 9 pull requests Successful merges: - rust-lang/rust#141967 (Configure bootstrap backport nominations through triagebot) - rust-lang/rust#142042 (Make E0621 missing lifetime suggestion verbose) - rust-lang/rust#142272 (tests: Change ABIs in tests to more future-resilient ones) - rust-lang/rust#142282 (Only run `citool` tests on the `auto` branch) - rust-lang/rust#142297 (Implement `//@ needs-target-std` compiletest directive) - rust-lang/rust#142298 (Make loongarch-none target maintainers more easily pingable) - rust-lang/rust#142306 (Dont unwrap and re-wrap typing envs) - rust-lang/rust#142324 (Remove unneeded `FunctionCx` from some codegen methods) - rust-lang/rust#142328 (feat: Add `bit_width` for unsigned integer types) Failed merges: - rust-lang/rust#141639 (Expose discriminant values in stable_mir) r? `@ghost` `@rustbot` modify labels: rollup

ignore `run-make` tests that need `std` on targets without `std` In particular, anything that includes `none` in the target triple, and `nvptx64-nvidia-cuda`. Right now we don't cross-compile the `run-make` tests, but we want to in the future. This uses `//@ needs-target-std` introduced in #142297. Useful for #139244 and #141856. The modified files are based on running #141856 locally. It might be that #139244 uncovers some additional files, but that PR needs to be rebased (though actually I'd advice to rebase the non-test changes onto this PR, probably faster that way). r? `@jieyouxu` <details> <summary>vim notes for future me</summary> Make a file with lines like this ``` /home/folkertdev/rust/rust/tests/run-make/export/disambiguator/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/invalid-so/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/no-builtins-attribute/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/export/extern-opt/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/link-dedup/rmake.rs:1:1 ``` then ``` :set errorformat=%f:%l:%c :cfile /tmp/files-to-fix.txt ``` ``` :copen :cnext :cprev ``` are your friends </details> try-job: test-various try-job: armhf-gnu

…ieyouxu ignore `run-make` tests that need `std` on targets without `std` In particular, anything that includes `none` in the target triple, and `nvptx64-nvidia-cuda`. Right now we don't cross-compile the `run-make` tests, but we want to in the future. This uses `//@ needs-target-std` introduced in rust-lang#142297. Useful for rust-lang#139244 and rust-lang#141856. The modified files are based on running rust-lang#141856 locally. It might be that rust-lang#139244 uncovers some additional files, but that PR needs to be rebased (though actually I'd advice to rebase the non-test changes onto this PR, probably faster that way). r? `@jieyouxu` <details> <summary>vim notes for future me</summary> Make a file with lines like this ``` /home/folkertdev/rust/rust/tests/run-make/export/disambiguator/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/invalid-so/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/no-builtins-attribute/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/export/extern-opt/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/link-dedup/rmake.rs:1:1 ``` then ``` :set errorformat=%f:%l:%c :cfile /tmp/files-to-fix.txt ``` ``` :copen :cnext :cprev ``` are your friends </details>

…ieyouxu ignore `run-make` tests that need `std` on targets without `std` In particular, anything that includes `none` in the target triple, and `nvptx64-nvidia-cuda`. Right now we don't cross-compile the `run-make` tests, but we want to in the future. This uses `//@ needs-target-std` introduced in rust-lang#142297. Useful for rust-lang#139244 and rust-lang#141856. The modified files are based on running rust-lang#141856 locally. It might be that rust-lang#139244 uncovers some additional files, but that PR needs to be rebased (though actually I'd advice to rebase the non-test changes onto this PR, probably faster that way). r? ``@jieyouxu`` <details> <summary>vim notes for future me</summary> Make a file with lines like this ``` /home/folkertdev/rust/rust/tests/run-make/export/disambiguator/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/invalid-so/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/no-builtins-attribute/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/export/extern-opt/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/link-dedup/rmake.rs:1:1 ``` then ``` :set errorformat=%f:%l:%c :cfile /tmp/files-to-fix.txt ``` ``` :copen :cnext :cprev ``` are your friends </details>

Rollup merge of #142414 - folkertdev:ignore-nostd-tests, r=jieyouxu ignore `run-make` tests that need `std` on targets without `std` In particular, anything that includes `none` in the target triple, and `nvptx64-nvidia-cuda`. Right now we don't cross-compile the `run-make` tests, but we want to in the future. This uses `//@ needs-target-std` introduced in #142297. Useful for #139244 and #141856. The modified files are based on running #141856 locally. It might be that #139244 uncovers some additional files, but that PR needs to be rebased (though actually I'd advice to rebase the non-test changes onto this PR, probably faster that way). r? ``@jieyouxu`` <details> <summary>vim notes for future me</summary> Make a file with lines like this ``` /home/folkertdev/rust/rust/tests/run-make/export/disambiguator/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/invalid-so/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/no-builtins-attribute/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/export/extern-opt/rmake.rs:1:1 /home/folkertdev/rust/rust/tests/run-make/link-dedup/rmake.rs:1:1 ``` then ``` :set errorformat=%f:%l:%c :cfile /tmp/files-to-fix.txt ``` ``` :copen :cnext :cprev ``` are your friends </details>

jieyouxu added 3 commits June 10, 2025 22:10

Extract target no-std hack to build_helpers

8ef8062

To centralize this hack in one place with a backlink to the issue tracking this hack, as this logic is also needed by compiletest to implement a `//@ needs-target-std` directive.

Implement //@ needs-target-std directive in compiletest

e10b2f6

To support tests to condition their (potentially cross-compile) execution based on whether the target supports std.

Document //@ needs-target-std in rustc-dev-guide

c5b8123

rustbot assigned Mark-Simulacrum Jun 10, 2025

Kobzol reviewed Jun 10, 2025

View reviewed changes

tests/run-make/cpp-global-destructors/rmake.rs Show resolved Hide resolved

jieyouxu force-pushed the needs-target-std branch from 67affa4 to cc61ec7 Compare June 10, 2025 15:29

jieyouxu commented Jun 10, 2025

View reviewed changes

tests/run-make/export-executable-symbols/rmake.rs Outdated Show resolved Hide resolved

Modify some run-make tests to use //@ needs-target-std

c558db3

Instead of a jumble of `ignore-$target`s, `ignore-none` and `ignore-nvptx`.

jieyouxu force-pushed the needs-target-std branch from cc61ec7 to c558db3 Compare June 10, 2025 15:31

rustbot assigned Kobzol and unassigned Mark-Simulacrum Jun 10, 2025

rustbot added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Jun 10, 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-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Jun 10, 2025

fmease mentioned this pull request Jun 10, 2025

Rollup of 13 pull requests #142313

Closed

workingjubilee mentioned this pull request Jun 11, 2025

Rollup of 17 pull requests #142332

Closed

workingjubilee mentioned this pull request Jun 11, 2025

Rollup of 13 pull requests #142333

Closed

This was referenced Jun 11, 2025

Rollup of 10 pull requests #142342

Closed

Rollup of 9 pull requests #142358

Merged

bors merged commit 57bb38b into rust-lang:master Jun 11, 2025
10 checks passed

rustbot added this to the 1.89.0 milestone Jun 11, 2025

jieyouxu deleted the needs-target-std branch June 11, 2025 23:07

folkertdev mentioned this pull request Jun 12, 2025

ignore run-make tests that need std on targets without std #142414

Merged

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Implement `//@ needs-target-std` compiletest directive #142297

Implement `//@ needs-target-std` compiletest directive #142297

Uh oh!

jieyouxu commented Jun 10, 2025 •

edited

Loading

Uh oh!

rustbot commented Jun 10, 2025

Uh oh!

Kobzol left a comment

Uh oh!

Uh oh!

Uh oh!

jieyouxu commented Jun 10, 2025

Uh oh!

Kobzol commented Jun 10, 2025

Uh oh!

Urgau commented Jun 10, 2025

Uh oh!

jieyouxu commented Jun 10, 2025 •

edited

Loading

Uh oh!

jieyouxu commented Jun 10, 2025

Uh oh!

rust-bors bot commented Jun 10, 2025

Uh oh!

jieyouxu commented Jun 10, 2025

Uh oh!

rust-bors bot commented Jun 10, 2025

Uh oh!

jieyouxu commented Jun 10, 2025

Uh oh!

bors commented Jun 10, 2025

Uh oh!

Uh oh!

Uh oh!

Implement //@ needs-target-std compiletest directive #142297

Implement //@ needs-target-std compiletest directive #142297

Uh oh!

Conversation

jieyouxu commented Jun 10, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Summary

Implementation limitation

Auxiliary changes

Footnotes

Uh oh!

rustbot commented Jun 10, 2025

Uh oh!

Kobzol left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

jieyouxu commented Jun 10, 2025

Uh oh!

Kobzol commented Jun 10, 2025

Uh oh!

Urgau commented Jun 10, 2025

Uh oh!

jieyouxu commented Jun 10, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

jieyouxu commented Jun 10, 2025

Uh oh!

rust-bors bot commented Jun 10, 2025

Uh oh!

jieyouxu commented Jun 10, 2025

Uh oh!

rust-bors bot commented Jun 10, 2025

Uh oh!

jieyouxu commented Jun 10, 2025

Uh oh!

bors commented Jun 10, 2025

Uh oh!

Uh oh!

Uh oh!

Implement `//@ needs-target-std` compiletest directive #142297

Implement `//@ needs-target-std` compiletest directive #142297

jieyouxu commented Jun 10, 2025 •

edited

Loading

jieyouxu commented Jun 10, 2025 •

edited

Loading