Rust-analyzer fails to start with the latest nightly due to `--lockfile-path`

[theoparis]

2026-02-26T22:06:26.026236-08:00  WARN `cargo metadata` failed and returning succeeded result with `--no-deps` error=`cargo metadata` exited with an error: error: unexpected argument '--lockfile-path' found

  tip: a similar argument exists: '--locked'

Usage: cargo metadata --format-version <VERSION> --manifest-path <PATH> --filter-platform <TRIPLE> --locked

For more information, try '--help'.


Stack backtrace:
   0: <std::backtrace::Backtrace>::create
   1: <anyhow::Error as core::convert::From<cargo_metadata::errors::Error>>::from
   2: <project_model::cargo_workspace::FetchMetadata>::exec::{closure#2}
   3: <project_model::cargo_workspace::FetchMetadata>::exec
   4: <project_model::sysroot::Sysroot>::load_workspace
   5: std::sys::backtrace::__rust_begin_short_backtrace::<<project_model::workspace::ProjectWorkspace>::load_cargo::{closure#1}::{closure#4}, core::option::Option<project_model::sysroot::RustLibSrcWorkspace>>
   6: <std::thread::lifecycle::spawn_unchecked<<project_model::workspace::ProjectWorkspace>::load_cargo::{closure#1}::{closure#4}, core::option::Option<project_model::sysroot::RustLibSrcWorkspace>>::{closure#1} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
   7: <std::sys::thread::unix::Thread>::new::thread_start
   8: __pthread_cond_wait

theo@Theos-MacBook-Pro theos % rustc -Vv
rustc 1.95.0-nightly (6a979b3e3 2026-02-26)
binary: rustc
commit-hash: 6a979b3e32522049d0acb4a47f7ae44b7c8abfd5
commit-date: 2026-02-26
host: aarch64-apple-darwin
release: 1.95.0-nightly
LLVM version: 22.1.0
theo@Theos-MacBook-Pro theos % rust-analyzer --version
rust-analyzer 1.95.0-nightly (6a979b3e 2026-02-26)

[theoparis]

Hm.... I guess i could revert to an older commit #21630

Downgrading cargo to 9b1b7a492975506b5a0c0325f8728f3740762830 does fix it for now.

[lnicola]

rust-lang/rust#153067 maybe?

[ShoyuVanilla]

rust-lang/rust#153067 maybe?

Haven't we synced r-a with the fix before it with rust-lang/rust#153007 ?
Maybe I have messed up sth?

Do the latest binaries from the rust-analyzer release page have the same problem?

[lnicola]

Hmm, I thought it's because we synced too early (before the cargo subtree sync), but it's actually complaining about --lockfile-path, not -Zlockfile-path, so that's not it.

[ShoyuVanilla]

Hmm, I thought it's because we synced too early (before the cargo subtree sync), but it's actually complaining about --lockfile-path, not -Zlockfile-path, so that's not it.

Yeah, that wouldn't be the case.

Or there's another possibility. @theoparis Are you on some text editors like visual studio code and installed rust-analyzer extension from editor's marketplace? If so, the rust-analyzer version you are getting from the terminal (from toolchain) is different from the editor's one (a binary that bundled with the extension). In that case, your rust-analyzer extension might not be the latest version.

[lnicola]

I suspect it's the way we compare them:

toolchain_version=Version { major: 1, minor: 95, patch: 0, pre: Prerelease("nightly") }
MINIMUM_TOOLCHAIN_VERSION_SUPPORTING_LOCKFILE_PATH_ENV=Version { major: 1, minor: 95, patch: 0 }
new_enough=false

let new_enough = *toolchain_version >= MINIMUM_TOOLCHAIN_VERSION_SUPPORTING_LOCKFILE_PATH_ENV;
tracing::error!(
    ?toolchain_version,
    ?MINIMUM_TOOLCHAIN_VERSION_SUPPORTING_LOCKFILE_PATH_ENV,
    ?new_enough
);

We can set pre in MINIMUM_TOOLCHAIN_VERSION_SUPPORTING_LOCKFILE_PATH_ENV, but that will lose compatibility with earlier nightlies (which is fine by me).

[theoparis]

I am using VSCode, however I did try setting the server path to /Users/theo/.cargo/bin/rust-analyzer earlier.

[ShoyuVanilla]

I suspect it's the way we compare them:

toolchain_version=Version { major: 1, minor: 95, patch: 0, pre: Prerelease("nightly") }
MINIMUM_TOOLCHAIN_VERSION_SUPPORTING_LOCKFILE_PATH_ENV=Version { major: 1, minor: 95, patch: 0 }
new_enough=false

let new_enough = *toolchain_version >= MINIMUM_TOOLCHAIN_VERSION_SUPPORTING_LOCKFILE_PATH_ENV;
tracing::error!(
?toolchain_version,
?MINIMUM_TOOLCHAIN_VERSION_SUPPORTING_LOCKFILE_PATH_ENV,
?new_enough
);

We can set pre in MINIMUM_TOOLCHAIN_VERSION_SUPPORTING_LOCKFILE_PATH_ENV, but that will lose compatibility with earlier nightlies (which is fine by me).

Oh, this feels most plausible. Yeah, my bad not considering nigthly rustc 😭

[RalfJung]

Thanks for the quick fix! Would be nice to get this synced to the rustc repo to unbreak RA on projects like Miri. :)

[lnicola]

I'll try to do a sync tomorrow, then backport it to the new beta.