rust-analyzer failed to load workspace again

[rsignavong]

Sorry to reopen this issue #4172 but the issue is still running and is not due to local toolchain installation.
It is more the difference of folders of rust-src between stable and nightly.

I have both stable and nightly and both have rust-src component installed but the folder inside rust-src is not the same for both toolchains.

In stable, rust-src contains an src folder and the requested libcore folder inside to load the workspace.
In nightly, rust-src contains only library and so rust-analyzer still tries to load src/libcore in nightly active toolchain.

And so the following still error occurs:

rust-analyzer failed to load workspace: Failed to find sysroot for Cargo.toml file /Users/.../workspace/.../Cargo.toml. Is rust-src installed?:
 could not find libcore in sysroot path `/Users/.../.rustup/toolchains/nightly-x86_64-apple-darwin/lib/rustlib/src/rust/src`

[bjorn3]

What rust-analyzer version are you using?

[rsignavong]

I tried the latest release 0d03fe6.
And just now I tried with 3877421 built from source master branch, I still got the same error.

[bjorn3]

What is the output of ls -R $(rustc --print sysroor)/lib/rustlib/src/rust?

[rsignavong]

There are many lines with the -R option.

Here is what I have

~ on ☁️  us-east-1
❯ rustup override set stable
info: using existing install for 'stable-x86_64-apple-darwin'
info: override toolchain for '/Users/rockysignavong' set to 'stable-x86_64-apple-darwin'

  stable-x86_64-apple-darwin unchanged - rustc 1.46.0 (04488afe3 2020-08-24)


~ on ☁️  us-east-1
❯ rustup show
Default host: x86_64-apple-darwin
rustup home:  /Users/rockysignavong/.rustup

installed toolchains
--------------------

stable-x86_64-apple-darwin (default)
nightly-x86_64-apple-darwin

active toolchain
----------------

stable-x86_64-apple-darwin (directory override for '/Users/rockysignavong')
rustc 1.46.0 (04488afe3 2020-08-24)


~ on ☁️  us-east-1
❯ ls $(rustc --print sysroot)/lib/rustlib/src/rust

 Cargo.lock   src

~ on ☁️  us-east-1
❯ rustup override set nightly
info: using existing install for 'nightly-x86_64-apple-darwin'
info: override toolchain for '/Users/rockysignavong' set to 'nightly-x86_64-apple-darwin'

  nightly-x86_64-apple-darwin unchanged - rustc 1.48.0-nightly (6af1bdda5 2020-09-15)


~ on ☁️  us-east-1
❯ rustup show
Default host: x86_64-apple-darwin
rustup home:  /Users/rockysignavong/.rustup

installed toolchains
--------------------

stable-x86_64-apple-darwin (default)
nightly-x86_64-apple-darwin

installed targets for active toolchain
--------------------------------------

wasm32-unknown-unknown
x86_64-apple-darwin

active toolchain
----------------

nightly-x86_64-apple-darwin (directory override for '/Users/rockysignavong')
rustc 1.48.0-nightly (6af1bdda5 2020-09-15)


~ on ☁️  us-east-1
❯ ls $(rustc --print sysroot)/lib/rustlib/src/rust

 Cargo.lock   library

[rsignavong]

as you can see, there is src in stable and library in nightly

[rsignavong]

and using grep libcore

~ on ☁️  us-east-1
❯ rustup override set stable
info: using existing install for 'stable-x86_64-apple-darwin'
info: override toolchain for '/Users/rockysignavong' set to 'stable-x86_64-apple-darwin'

  stable-x86_64-apple-darwin unchanged - rustc 1.46.0 (04488afe3 2020-08-24)


~ on ☁️  us-east-1
❯ ls -R $(rustc --print sysroot)/lib/rustlib/src/rust | rg libcore

libcore
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/alloc:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/array:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/benches:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/benches/ascii:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/benches/char:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/benches/hash:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/benches/num:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/benches/num/dec2flt:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/benches/num/flt2dec:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/benches/num/flt2dec/strategy:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/char:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/convert:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/fmt:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/fmt/rt:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/future:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/hash:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/iter:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/iter/adapters:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/iter/traits:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/macros:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/mem:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/num:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/num/dec2flt:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/num/flt2dec:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/num/flt2dec/strategy:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/ops:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/prelude:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/ptr:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/slice:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/str:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/sync:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/task:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/tests:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/tests/fmt:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/tests/hash:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/tests/num:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/tests/num/dec2flt:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/tests/num/flt2dec:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/tests/num/flt2dec/strategy:
/Users/rockysignavong/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/unicode:

~ on ☁️  us-east-1
❯ rustup override set nightly
info: using existing install for 'nightly-x86_64-apple-darwin'
info: override toolchain for '/Users/rockysignavong' set to 'nightly-x86_64-apple-darwin'

  nightly-x86_64-apple-darwin unchanged - rustc 1.48.0-nightly (6af1bdda5 2020-09-15)


~ on ☁️  us-east-1
❯ ls -R $(rustc --print sysroot)/lib/rustlib/src/rust | rg libcore


~ on ☁️  us-east-1
❯

[sunjay]

It looks like this issue is being caused by the recent reorg of the rust-lang/rust repo. As mentioned in the original issue, the src directory is now named library.

I ran rustup update so the info below is with rustc 1.48.0-nightly (6af1bdda5 2020-09-15) (from rustc 1.48.0-nightly (a1947b3f9 2020-09-10)).

rust-analyzer is trying to find the path:

~/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/src

But the actual path that exists is:

~/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library

If anyone else is looking to temporarily work around the solution just to get their setup working again, you can use:

ln -s ~/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library ~/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/src

Simply renaming the directory to src will probably work too, though I haven't tried that.

[rsignavong]

I didn't think that aliasing will work as I thought rust-analyzer was looking for libcore that doesn't exist inside library but I tried @sunjay temporary solution with alias ln -s library src for nightly toolchain and it works! 👍

Thank you!

I hope this will be fixed soon.

[lnicola]

This should have been fixed in #5586. Do you have a RUST_SRC RUST_SRC_PATH environment variable?

[rsignavong]

I have RUST_SRC_PATH and changing src to library didn't work.
So I added RUST_SRC that target library and it works without the symlink src -> library (that I removed before testing).

Here is my .zshrc config for rust

# Rust
export RUST_SRC_PATH="$(rustc --print sysroot)/lib/rustlib/src/rust/src"
export RUST_SRC="$(rustc --print sysroot)/lib/rustlib/src/rust/library"

[lnicola]

Try unsetting those.

[rsignavong]

It works without those environment variable. Thank you! 👍
I thought it was mandatory to specify those. I don't really remember why I needed to set RUST_SRC_PATH, maybe for RLS and Racer.