Make miri easier to install

[RalfJung]

It would be great if we could make miri easier to install.

miri + cargo miri

One thing is getting miri (and cargo-miri) itself. The ideal solution here would be making this a component in rustup so that it comes with a matching nightly. The dev-tools team has said they would support us in getting that done, after the edition.

libstd

However, miri isn't extremely useful if libstd comes without all the MIR. Right now, I don't think just making it a component is going to do much good, if people still have to then clone our repo to run xargo/build.sh.

The best I can think of here is to do this automatically in miri itself: Basically, to move xargo/* into the miri library, and have a setup step in the beginning which automatically compiles and then uses an appropriate libstd. Sounds rather hacky, but does anyone have a better idea?

[RalfJung]

The second item above is solved: cargo miri now automatically installs and uses xargo.

What remains is distributing miri itself. @oli-obk you have some experience with clippy, can you help making miri a rustup component?

[oli-obk]

I'll do it over the holidays. I'll want to deduplicate some work between e.g. clippy and miri distribution instead of just copypasting everything.

[RalfJung]

Sounds great :)

[RalfJung]

@oli-obk what is the state of making Miri a rustup component?

[mati865]

I believe it should be available with next release of rustup (or with git checkout).

[RalfJung]

I thought rustup needs patching to hook cargo-miri, or so?

[mati865]

You mean rust-lang/rustup#1606?

[RalfJung]

Ah, I didn't know that already landed!

Whom should we bug for a rustup release?

[mati865]

Most of the releases were made by alexcrichton, Idk about the preferred way to contact.

[RalfJung]

@alexcrichton When do you usually make rustup releases? Would be nice to get one that includes the Miri support.

[alexcrichton]

It's just on-demand, there's no schedule currently. There's development happening on rustup right now and presumably when that reaches a good point a release can be made.

[aleksmelnikov]

@alexcrichton , new rustup release needs to testing of the first miri component installation.

[RalfJung]

It seems there was a new rustup release. What's next?

[oli-obk]

Curious:

➜  cargo miri
error: 'cargo-miri' is not installed for the toolchain 'nightly-x86_64-unknown-linux-gnu'
To install, run `rustup component add miri --toolchain nightly-x86_64-unknown-linux-gnu`
➜  rustup component add miri --toolchain nightly-x86_64-unknown-linux-gnu
error: toolchain 'nightly-x86_64-unknown-linux-gnu' does not contain component 'miri' for target 'x86_64-unknown-linux-gnu'

[mati865]

@oli-obk you didn't add it to https://github.com/rust-lang/rust/blob/88f755f8a84df1d9e6b17cf10c96ae8b93481b2e/src/tools/build-manifest/src/main.rs#L344

[oli-obk]

That explains it. I was sure I checked every clippy mention, but I might've only looked in bootstrap.

Thanks!

[mati865]

rust-lang/rust#58990 was merged, it should work with next nightly.

[aleksmelnikov]

Yes, miri is available in rustup component list now.

 rustup component list | grep miri
miri-x86_64-unknown-linux-gnu

But I cannot install it:

rustup component add miri
info: downloading component 'miri'
info: installing component 'miri'
info: rolling back changes
error: component manifest for 'miri' is corrupt

[RalfJung]

Also, shouldn't it be called miri-preview?

[aleksmelnikov]

@RalfJung ,

rustup component add miri-preview
error: toolchain 'nightly-x86_64-unknown-linux-gnu' does not contain component 'miri-preview' for target 'x86_64-unknown-linux-gnu'

[mati865]

I debugged rustup and there is mismatch between miri and miri-preview.
Rust's dist crates directory miri-preview but but the manifest tells rustup to look for miri.
Chaning miri-preview to miri is simple, the other way around requires a bit more work.

I can try to fix it but which name should be used miri or miri-preview?

[oli-obk]

if there's a discrepancy anyway, let's go with miri-preview in order to communicate the unstable nature of it

[mati865]

Opened rust-lang/rust#59236

[RalfJung]

@mati865 awesome, thanks!

But then I assume rustup also needs updating? With https://github.com/rust-lang/rustup.rs/pull/1606/files, it says to install miri when the cargo-miri binary is missing.

[mati865]

IIRC both miri and miri-preview should work because of rename.

[aleksmelnikov]

rustup component list | grep miri
miri-x86_64-unknown-linux-gnu

rustup component add miri
info: downloading component 'miri'
info: installing component 'miri'
info: rolling back changes
error: component manifest for 'miri' is corrupt

rustup component add miri-preview
error: toolchain 'nightly-x86_64-unknown-linux-gnu' does not contain component 'miri-preview' for target 'x86_64-unknown-linux-gnu'

Ping. It's still unavailable.

[mati865]

@superriva the PR isn't merged yet.

[orium]

rust-lang/rust#59236 landed. Does rustup need to be updated as well?

[mati865]

It landed 35 minutes late for the nightly, it should work tomorrow. sob., 23 mar 2019, 11:45 użytkownik Diogo Sousa <notifications@github.com> napisał:

…

rust-lang/rust#59236 <rust-lang/rust#59236> landed. Does rustup need to be updated as well? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#520 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABHsdpbSpSXcr2BejHrDT90X5D7hfGQiks5vZgXKgaJpZM4YdMdi> .

[mati865]

🎊 Seems to be finally fixed, running in clear container:

root@bc89da8c8ed5:/# rustup component add miri
info: downloading component 'miri'
info: installing component 'miri'
root@bc89da8c8ed5:/# cargo miri
It seems you do not have a recent enough xargo installed. I will run `cargo install xargo -f`. Proceed? [Y/n]
...

[oli-obk]

cc @shepmaster you can now install miri as a component instead of building it yourself

[RalfJung]

Awesome. :)

[orium]

The component doesn't seem to be available anymore:

$ rustup component add --toolchain nightly miri-preview
error: component 'miri' for target 'x86_64-unknown-linux-gnu' is unavailable for download for channel 'nightly'

[RalfJung]

Yeah, that is waiting for rust-lang/rust#59555 to land.

Just like Clippy and RLS, Miri sometimes gets broken by rustc changes and then a fix has to land before it can be installed via rustup again.