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@heiher heiher commented Aug 30, 2025

The loongarch64-unknown-none target is a bare-metal target with hardware floating-point support and should not enable SIMD extensions by default. However, LLVM's LoongArch64 backend enables LSX implicitly, inadvertently activating SIMD instructions for this target. This patch explicitly disable LSX feature to prevent unintended SIMD usage.

The `loongarch64-unknown-none` target is a bare-metal target with
hardware floating-point support and should not enable SIMD extensions
by default. However, LLVM's LoongArch64 backend enables LSX implicitly,
inadvertently activating SIMD instructions for this target. This patch
explicitly disable LSX feature to prevent unintended SIMD usage.
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rustbot commented Aug 30, 2025

r? @jackh726

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@rustbot rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Aug 30, 2025
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rustbot commented Aug 30, 2025

These commits modify compiler targets.
(See the Target Tier Policy.)

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lqd commented Sep 2, 2025

Thanks!

r? lqd @bors r+ rollup

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bors commented Sep 2, 2025

📌 Commit 0b1bc65 has been approved by lqd

It is now in the queue for this repository.

@bors 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 Sep 2, 2025
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jackh726 commented Sep 2, 2025

I wanted to ask

bare-metal target with hardware floating-point support and should not enable SIMD extensions by default

why is this?

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lqd commented Sep 2, 2025

It should be like x86, they are extensions that are not necessarily supported by the cpu baseline defined by the target.

GuillaumeGomez added a commit to GuillaumeGomez/rust that referenced this pull request Sep 2, 2025
Explicity disable LSX feature for `loongarch64-unknown-none` target

The `loongarch64-unknown-none` target is a bare-metal target with hardware floating-point support and should not enable SIMD extensions by default. However, LLVM's LoongArch64 backend enables LSX implicitly, inadvertently activating SIMD instructions for this target. This patch explicitly disable LSX feature to prevent unintended SIMD usage.
GuillaumeGomez added a commit to GuillaumeGomez/rust that referenced this pull request Sep 2, 2025
Explicity disable LSX feature for `loongarch64-unknown-none` target

The `loongarch64-unknown-none` target is a bare-metal target with hardware floating-point support and should not enable SIMD extensions by default. However, LLVM's LoongArch64 backend enables LSX implicitly, inadvertently activating SIMD instructions for this target. This patch explicitly disable LSX feature to prevent unintended SIMD usage.
bors added a commit that referenced this pull request Sep 2, 2025
Rollup of 8 pull requests

Successful merges:

 - #139113 (unstable book: in a sanitizer example, check the code)
 - #145823 (editorconfig: don't use nonexistent syntax)
 - #145962 (Ensure we emit an allocator shim when only some crate types need one)
 - #146032 (Explicity disable LSX feature for `loongarch64-unknown-none` target)
 - #146090 (Derive `PartialEq` for `InvisibleOrigin`)
 - #146120 (Correct typo in `rustc_errors` comment)
 - #146121 (fix: Filter suggestion parts that match existing code)
 - #146134 (llvm: nvptx: Layout update to match LLVM)

r? `@ghost`
`@rustbot` modify labels: rollup
tgross35 added a commit to tgross35/rust that referenced this pull request Sep 3, 2025
Explicity disable LSX feature for `loongarch64-unknown-none` target

The `loongarch64-unknown-none` target is a bare-metal target with hardware floating-point support and should not enable SIMD extensions by default. However, LLVM's LoongArch64 backend enables LSX implicitly, inadvertently activating SIMD instructions for this target. This patch explicitly disable LSX feature to prevent unintended SIMD usage.
bors added a commit that referenced this pull request Sep 3, 2025
Rollup of 8 pull requests

Successful merges:

 - #139113 (unstable book: in a sanitizer example, check the code)
 - #145279 (Constify conversion traits (part 1))
 - #145414 (unicode-table-generator refactors)
 - #145823 (editorconfig: don't use nonexistent syntax)
 - #145944 (std: Start supporting WASIp2 natively )
 - #145961 (resolve: Avoid a regression from splitting prelude into two scopes)
 - #146032 (Explicity disable LSX feature for `loongarch64-unknown-none` target)
 - #146106 (fix(lexer): Only allow horizontal whitespace in frontmatter )

r? `@ghost`
`@rustbot` modify labels: rollup
bors added a commit that referenced this pull request Sep 3, 2025
Rollup of 8 pull requests

Successful merges:

 - #139113 (unstable book: in a sanitizer example, check the code)
 - #145279 (Constify conversion traits (part 1))
 - #145414 (unicode-table-generator refactors)
 - #145823 (editorconfig: don't use nonexistent syntax)
 - #145944 (std: Start supporting WASIp2 natively )
 - #145961 (resolve: Avoid a regression from splitting prelude into two scopes)
 - #146032 (Explicity disable LSX feature for `loongarch64-unknown-none` target)
 - #146106 (fix(lexer): Only allow horizontal whitespace in frontmatter )

r? `@ghost`
`@rustbot` modify labels: rollup
Zalathar added a commit to Zalathar/rust that referenced this pull request Sep 3, 2025
Explicity disable LSX feature for `loongarch64-unknown-none` target

The `loongarch64-unknown-none` target is a bare-metal target with hardware floating-point support and should not enable SIMD extensions by default. However, LLVM's LoongArch64 backend enables LSX implicitly, inadvertently activating SIMD instructions for this target. This patch explicitly disable LSX feature to prevent unintended SIMD usage.
bors added a commit that referenced this pull request Sep 3, 2025
Rollup of 9 pull requests

Successful merges:

 - #145279 (Constify conversion traits (part 1))
 - #145414 (unicode-table-generator refactors)
 - #145823 (editorconfig: don't use nonexistent syntax)
 - #145944 (std: Start supporting WASIp2 natively )
 - #145961 (resolve: Avoid a regression from splitting prelude into two scopes)
 - #146032 (Explicity disable LSX feature for `loongarch64-unknown-none` target)
 - #146106 (fix(lexer): Only allow horizontal whitespace in frontmatter )
 - #146112 (don't uppercase error messages)
 - #146154 (CI: rfl: move job forward to Linux v6.17-rc3 plus 2 commits)

r? `@ghost`
`@rustbot` modify labels: rollup
bors added a commit that referenced this pull request Sep 3, 2025
Rollup of 8 pull requests

Successful merges:

 - #145279 (Constify conversion traits (part 1))
 - #145414 (unicode-table-generator refactors)
 - #145823 (editorconfig: don't use nonexistent syntax)
 - #145944 (std: Start supporting WASIp2 natively )
 - #145961 (resolve: Avoid a regression from splitting prelude into two scopes)
 - #146032 (Explicity disable LSX feature for `loongarch64-unknown-none` target)
 - #146106 (fix(lexer): Only allow horizontal whitespace in frontmatter )
 - #146154 (CI: rfl: move job forward to Linux v6.17-rc3 plus 2 commits)

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit 1ec369e into rust-lang:master Sep 3, 2025
10 checks passed
@rustbot rustbot added this to the 1.91.0 milestone Sep 3, 2025
rust-timer added a commit that referenced this pull request Sep 3, 2025
Rollup merge of #146032 - heiher:loong64-none-no-lsx, r=lqd

Explicity disable LSX feature for `loongarch64-unknown-none` target

The `loongarch64-unknown-none` target is a bare-metal target with hardware floating-point support and should not enable SIMD extensions by default. However, LLVM's LoongArch64 backend enables LSX implicitly, inadvertently activating SIMD instructions for this target. This patch explicitly disable LSX feature to prevent unintended SIMD usage.
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