matrix-sdk-crypto from crates.io fails to compile

[VerdeQuar]

Maintainer update

The issue has been identified as an accidental breaking change in a dependency. While we are looking into the best way foward, you can work around the issue by downgrading tracing-attributes:

cargo update -p tracing-attributes --precise 0.1.28

Original issue description

I was doing some work on a different project and everything was working fine, until i did cargo update, despite matrix_sdk being still in version 0.11.0 like it was before, it for some reason stopped compiling and gave me this error:

error[E0573]: expected type, found variant `CryptoStoreError`
    --> /home/verdek/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/matrix-sdk-crypto-0.11.0/src/identities/manager.rs:1182:21
     |
44   |     CryptoStoreError, LocalTrust, OwnUserIdentity, SignatureError, UserIdentity,
     |     ---------------- you might have meant to refer to this enum
...
1182 |     ) -> Result<(), CryptoStoreError> {
     |                     ^^^^^^^^^^^^^^^^ not a type

For more information about this error, try `rustc --explain E0573`.
error: could not compile `matrix-sdk-crypto` (lib) due to 1 previous error

i tested it on an empty project in which i just did cargo add matrix_sdk and it also doesn't compile
i'm on stable rust 1.87.0 but when i switched to 1.86.0 i got the same error
same thing with downgrading to matrix_sdk 0.10.0

seems very weird that that kind of error would go unnoticed for so long, so i have no idea if this is even reproducible, but i found that removing this wildcard import solves the issue
which seems even weirder cause i would assume that import would only work inside the scope of the function, but it somehow triggers an error in its signature
in any case, wildcard imports of enum variants are very error prone so it shouldn't even be there in the first place, should i make a pr?

[jplatte]

What an interesting bug! I suspect you will be able to reproduce it here in the repo but updating the lockfile with cargo update. And I agree with removing the wildcard import as a fix.

[VerdeQuar]

Actually this repo as well as crates/matrix-sdk-crypto on its own, both do compile for me after cargo update
both on main and on matrix-sdk-0.11.0 tag so i'm not sure what's wrong
either way, i'm sending the pr

[jplatte]

What if you update your own lockfile in the project where you got this error? Does that fix the issue? If yes, which packages just updated?

[VerdeQuar]

no, that introduced the error before, i was using matrix-sdk just fine before runing cargo update
unfortunately i did not have that project in a git repo at that time so i'm unable to go back to the previous version of the lockfile to compare, but the project was created 5 days ago and at that time cargo add matrix-sdk should have downloaded the same version cargo update and cargo add on a fresh project both do today
i also did a system update(arch linux) in the meantime, but rust is managed by rustup so that also shouldn't make any difference, rust itself did not update nor did cargo
i'm guessing you cannot reproduce the issue on an empty rust project?

[VerdeQuar]

so it turns out that rustup did update to 1.28.2-2, not sure if it updates the toolchain automatically along with itself, but that seems to be the only thing that changed

[m13253]

I can reproduce it today.

macOS 15.5 (24F74)
rustc 1.87.0 (17067e9ac 2025-05-09)
matrix-sdk-crypto v0.11.0

error[E0573]: expected type, found variant `CryptoStoreError`
    --> ~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/matrix-sdk-crypto-0.11.0/src/identities/manager.rs:1126:21
     |
44   |     CryptoStoreError, LocalTrust, OwnUserIdentity, SignatureError, UserIdentity,
     |     ---------------- you might have meant to refer to this enum
...
1126 |     ) -> Result<(), CryptoStoreError> {
     |                     ^^^^^^^^^^^^^^^^ not a type

Interestingly, yesterday it was all good.
It only became bad today.

I updated nothing.

[jplatte]

@m13253 Can you rename your target directory (i.e. reset all caches without deleting them) and try again? I wonder whether this is an incremental compilation bug or something along those lines 🤔

[m13253]

@jplatte

I deleted target, deleted Cargo.lock, and cleaned system-wide ~/.cargo/registry cache through cargo-cache -a.

Still the same error.

[jplatte]

so it turns out that rustup did update to 1.28.2-2, not sure if it updates the toolchain automatically along with itself, but that seems to be the only thing that changed

Updating rustup should not change anything about the toolchain, as far as I know.

[jplatte]

I'll reopen this because I think #5191 should be backported to 0.11.x and maybe also 0.10.x on crates.io.

I just tested by adding matrix-sdk-crypto = "0.11.0" to a project that otherwise has no dependencies, and could reproduce the issue.

[m13253]

I'll reopen this because I think #5191 should be backported to 0.11.x and maybe also 0.10.x on crates.io.

I agree with you.
A lot of downstream applications can’t yet use the “git head” version of matrix-rust-sdk due to their complex indirect-dependency trees.

When are we going to have a crate publish?
I think we should only be safe to close the issue after that.

[jplatte]

Alright, I figured it out. It's nothing to do with the Rust toolchain. The function that is causing the issue uses the tracing::instrument proc-macro attribute (re-exported from tracing-attributes). Downgrading tracing-attributes fixes it:

cargo update -p tracing-attributes --precise 0.1.28

I'm now looking into what happened. May actually be a PR I personally merged into tracing-attributes 🥲