Re: [PATCH] rust: Kbuild: set frame-pointer llvm module flag for CONFIG_FRAME_POINTER

[Miguel Ojeda]

On Tue, Jun 16, 2026 at 2:30 PM Alice Ryhl <aliceryhl@xxxxxxxxxx> wrote:
>
> Cc: stable@xxxxxxxxxx
> Fixes: 2f7ab1267dc9 ("Kbuild: add Rust support")

For 6.1.y, we use Rust 1.62.0, so we don't have `-Zllvm_module_flag`,
so we cannot go that far back. I guess we will need to accept the
issue there.

For 6.6.y, we use Rust 1.73.0, so we don't have it either.

For 6.12.y onward, we support Rust 1.78.0, so it is fine --
`-Zllvm_module_flag` got added in Rust 1.76.0.

In both 6.1.y and 6.6.y, we also don't have `rustc-min-version`,
because the version is pinned there. That part happens to work,
though, just due to how lax Make is... However, if the flag had been
available, then we should probably still do it cleanly with a custom
patch to avoid confusion.

So I will instead do:

Cc: stable@xxxxxxxxxxxxxxx # 6.12.y and later (flag not available in
pinned Rust in older LTSs).

Cheers,
Miguel