NVPTX: Drop support for old architectures and old ISAs by kjetilkjeka · Pull Request #152443 · rust-lang/rust

kjetilkjeka · 2026-02-10T16:29:16Z

This is the implementation of this MCP

I believe it was said that no FCP was needed, but if that is incorrect then the FCP is anyway scheduled to finish in 2 days so it can in any case be merged then.

rustbot · 2026-02-10T16:29:21Z

Some changes occurred in src/doc/rustc/src/platform-support

cc @Noratrieb

rustbot · 2026-02-10T16:29:24Z

r? @jackh726

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kjetilkjeka · 2026-02-10T16:30:19Z

r? @ZuseZ4

kjetilkjeka · 2026-02-10T16:31:27Z

CC: @workingjubilee @kulst

kjetilkjeka · 2026-02-10T16:32:04Z

@rustbot label +O-NVPTX

ZuseZ4 · 2026-02-11T21:13:34Z

Changing a target baseline officially doesn't require a blog post: https://forge.rust-lang.org/compiler/proposals-and-stabilization.html#other-kind-of-target-changes

But since it's afaik the first time that we raise it for a GPU target and since nvptx is Tier 2, would you mind to still write one, so that we could merge it simultaneously?

https://blog.rust-lang.org/2023/09/25/Increasing-Apple-Version-Requirements/ and https://blog.rust-lang.org/2025/08/19/demoting-x86-64-apple-darwin-to-tier-2-with-host-tools/ are two related examples, but there are more if you want some inspiration.

Just a more user-friendly, short version of your MCP. Something motivating the change, mentioning the new behaviour, and saying that we will likely raise it further in the future, would be enough.

CodesInChaos · 2026-02-12T10:50:12Z

So this drops support for Pascal (10 series, P100), while keeping support for Volta (V100) and Turing (16 and 20 series)? Perhaps including that information in the docs would be helpful.

kjetilkjeka · 2026-03-04T17:01:30Z

With regards to blogpost, is something like this acceptable? rust-lang/blog.rust-lang.org#1810

So this drops support for Pascal (10 series, P100), while keeping support for Volta (V100) and Turing (16 and 20 series)? Perhaps including that information in the docs would be helpful.

Yes. I linked to the document by Nvidia listing all their GPUs as it will quickly become very verbose to explicitly list a lot of GPUs. Let me know if you think it's easier to get hold of this information with these changes.

Since the branch date for 1.95 was approaching I decided to instead wait for 1.96. The version is stated to be 1.96 in the docs and blogpost right now and we should have plenty of time for that branch date.

ZuseZ4 · 2026-03-29T23:05:40Z

 While the compiler accepts `#[target_feature(enable = "ptx80", enable = "sm_89")]`, it is not supported, may not behave as intended, and may become erroneous in the future.

+## Minimum SM and PTX support by Rust version
+Old hardware architectures and PTX ISA versions are periodically dropped support for. This table shows the minimum supported versions per Rust version.


Nit: Might just be because I'm not native, but it reads a bit awkward to me. Does

Support for old hardware architectures and PTX ISA versions is periodically dropped.

sound better?

Much more natural, thanks ❤️

ZuseZ4 · 2026-03-29T23:56:57Z

        },
    );

+    // This is needed to ensure that we don't use PTX ISA versions that we do not support


I just looked up the ptx-release-history link from this PR to verify that we don't need to handle sm_80. Can you make it slightly more explicit for the next reader by saying that sm_{70,72,75} would default to ptx60, which is unsupported, whereas sm_80 would default to ptx70, which is supported?

I made an attempt at making the comment a bit clearer and add that piece of information. I hope it's better now

rustbot · 2026-04-22T17:31:39Z

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

rustbot · 2026-04-22T19:59:30Z

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

kjetilkjeka · 2026-04-22T20:02:18Z

I addressed your review comments and updated the table of Rust releases to the correct set assuming this is merged before the next release. It should be ready for review

ZuseZ4 · 2026-04-26T19:14:48Z

Are you sure with the versions? I just checked releases.rs/docs/1.97.0/,
which says that the next time we'll branch off on May 22nd is gonna be for 1.97.
Otherwise lgtm.

kjetilkjeka · 2026-04-26T20:03:20Z

Are you sure with the versions? I just checked releases.rs/docs/1.97.0/, which says that the next time we'll branch off on May 22nd is gonna be for 1.97. Otherwise lgtm.

Are you referring to the blogpost MR? In that case it's fixed now. I believe this one states that the new behaviour is from 1.97

ZuseZ4 · 2026-04-26T20:14:07Z

Right. Thanks!

@bors r+

rust-bors · 2026-04-26T20:14:11Z

📌 Commit 1a8d8ae has been approved by ZuseZ4

It is now in the queue for this repository.

…_hw_and_isa, r=ZuseZ4 NVPTX: Drop support for old architectures and old ISAs This is the implementation of [this MCP](rust-lang/compiler-team#965 (comment)) I believe it was said that no FCP was needed, but if that is incorrect then the FCP is anyway scheduled to finish in 2 days so it can in any case be merged then.

…uwer Rollup of 9 pull requests Successful merges: - #149624 (Fix requires_lto targets needing lto set in cargo) - #152443 (NVPTX: Drop support for old architectures and old ISAs) - #155317 (`std::io::Take`: Clarify & optimize `BorrowedBuf::set_init` usage.) - #155588 (Implement more traits for FRTs) - #155682 (Add boxing suggestions for `impl Trait` return type mismatches) - #155770 (Avoid misleading closure return type note) - #155818 (Convert attribute `FinalizeFn` to fn pointer) - #155829 (rustc_attr_parsing: use a `try {}` in `or_malformed`) - #155835 (couple of `crate_name` cleanups)

jhpratt · 2026-04-27T01:56:06Z

@bors r-

#155845 (comment)

rust-bors · 2026-04-27T01:56:12Z

This pull request was unapproved.

This PR was contained in a rollup (#155845), which was unapproved.

View changes since this unapproval

rustbot assigned jackh726 Feb 10, 2026

rustbot assigned ZuseZ4 and unassigned jackh726 Feb 10, 2026

rustbot added the O-NVPTX Target: the NVPTX LLVM backend for running rust on GPUs, https://llvm.org/docs/NVPTXUsage.html label Feb 10, 2026

kjetilkjeka commented Feb 10, 2026

View reviewed changes

Comment thread compiler/rustc_target/src/target_features.rs

kjetilkjeka changed the title ~~NVPTX: Drop support for old hw and old ISAs~~ NVPTX: Drop support for old architectures and old ISAs Feb 10, 2026