[INFO] cloning repository https://github.com/semtexzv/vmaas-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/semtexzv/vmaas-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsemtexzv%2Fvmaas-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsemtexzv%2Fvmaas-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a23ef890d5d76dc910525d1eca04a5ea0182aa95
[INFO] checking semtexzv/vmaas-rs against beta-2021-10-15 for beta-1.56-3
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsemtexzv%2Fvmaas-rs" "/workspace/builds/worker-44/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-44/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/semtexzv/vmaas-rs on toolchain beta-2021-10-15
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-10-15" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/semtexzv/vmaas-rs
[INFO] finished tweaking git repo https://github.com/semtexzv/vmaas-rs
[INFO] tweaked toml for git repo https://github.com/semtexzv/vmaas-rs written to /workspace/builds/worker-44/source/Cargo.toml
[INFO] crate git repo https://github.com/semtexzv/vmaas-rs already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-10-15" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
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[INFO] [stderr]     Blocking waiting for file lock on package cache
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[INFO] running `Command { std: "docker" "start" "-a" "8610ee9060bc45c6f7c4cfa4b91f25e5f2179f64852d3a0e0be7f72a5c93c238", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8610ee9060bc45c6f7c4cfa4b91f25e5f2179f64852d3a0e0be7f72a5c93c238", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8610ee9060bc45c6f7c4cfa4b91f25e5f2179f64852d3a0e0be7f72a5c93c238", kill_on_drop: false }`
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[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-44/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-44/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-10-15" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
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[INFO] [stderr]     Checking jtool v0.1.0 (/opt/rustwide/workdir/jtool)
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a closure that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]    --> jtool/src/main.rs:4:59
[INFO] [stdout]     |
[INFO] [stdout] 4   |             arr.sort_by_cached_key(|v| json::to_string(&v)?);
[INFO] [stdout]     |                                    -----------------------^
[INFO] [stdout]     |                                    |                      |
[INFO] [stdout]     |                                    |                      cannot use the `?` operator in a closure that returns `std::string::String`
[INFO] [stdout]     |                                    this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]     |
[INFO] [stdout]     = help: the trait `FromResidual<Result<Infallible, serde_json::Error>>` is not implemented for `std::string::String`
[INFO] [stdout] note: required by `from_residual`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a closure that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]    --> jtool/src/main.rs:4:59
[INFO] [stdout]     |
[INFO] [stdout] 4   |             arr.sort_by_cached_key(|v| json::to_string(&v)?);
[INFO] [stdout]     |                                    -----------------------^
[INFO] [stdout]     |                                    |                      |
[INFO] [stdout]     |                                    |                      cannot use the `?` operator in a closure that returns `std::string::String`
[INFO] [stdout]     |                                    this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]     |
[INFO] [stdout]     = help: the trait `FromResidual<Result<Infallible, serde_json::Error>>` is not implemented for `std::string::String`
[INFO] [stdout] note: required by `from_residual`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]  --> jtool/src/main.rs:5:13
[INFO] [stdout]   |
[INFO] [stdout] 1 |   pub fn process(v: &mut json::Value) -> std::io::Result<()> {
[INFO] [stdout]   |                                          ------------------- expected `Result<(), std::io::Error>` because of return type
[INFO] [stdout] ...
[INFO] [stdout] 5 | /             arr.iter_mut().for_each(|v| {
[INFO] [stdout] 6 | |                 process(v);
[INFO] [stdout] 7 | |             })
[INFO] [stdout]   | |______________^ expected enum `Result`, found `()`
[INFO] [stdout]   |
[INFO] [stdout]   = note:   expected enum `Result<(), std::io::Error>`
[INFO] [stdout]           found unit type `()`
[INFO] [stdout] help: try using a variant of the expected enum
[INFO] [stdout]   |
[INFO] [stdout] 5 ~             Ok(arr.iter_mut().for_each(|v| {
[INFO] [stdout] 6 +                 process(v);
[INFO] [stdout] 7 +             }))
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking upcache v0.1.0 (/opt/rustwide/workdir/upcache)
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]  --> jtool/src/main.rs:5:13
[INFO] [stdout]   |
[INFO] [stdout] 1 |   pub fn process(v: &mut json::Value) -> std::io::Result<()> {
[INFO] [stdout]   |                                          ------------------- expected `Result<(), std::io::Error>` because of return type
[INFO] [stdout] ...
[INFO] [stdout] 5 | /             arr.iter_mut().for_each(|v| {
[INFO] [stdout] 6 | |                 process(v);
[INFO] [stdout] 7 | |             })
[INFO] [stdout]   | |______________^ expected enum `Result`, found `()`
[INFO] [stdout]   |
[INFO] [stdout]   = note:   expected enum `Result<(), std::io::Error>`
[INFO] [stdout]           found unit type `()`
[INFO] [stdout] help: try using a variant of the expected enum
[INFO] [stdout]   |
[INFO] [stdout] 5 ~             Ok(arr.iter_mut().for_each(|v| {
[INFO] [stdout] 6 +                 process(v);
[INFO] [stdout] 7 +             }))
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]   --> jtool/src/main.rs:10:13
[INFO] [stdout]    |
[INFO] [stdout] 1  |   pub fn process(v: &mut json::Value) -> std::io::Result<()> {
[INFO] [stdout]    |                                          ------------------- expected `Result<(), std::io::Error>` because of return type
[INFO] [stdout] ...
[INFO] [stdout] 10 | /             obj.iter_mut().for_each(|(k,v)| {
[INFO] [stdout] 11 | |                 process(v);
[INFO] [stdout] 12 | |             })
[INFO] [stdout]    | |______________^ expected enum `Result`, found `()`
[INFO] [stdout]    |
[INFO] [stdout]    = note:   expected enum `Result<(), std::io::Error>`
[INFO] [stdout]            found unit type `()`
[INFO] [stdout] help: try using a variant of the expected enum
[INFO] [stdout]    |
[INFO] [stdout] 10 ~             Ok(obj.iter_mut().for_each(|(k,v)| {
[INFO] [stdout] 11 +                 process(v);
[INFO] [stdout] 12 +             }))
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]   --> jtool/src/main.rs:14:14
[INFO] [stdout]    |
[INFO] [stdout] 14 |         _ => {}
[INFO] [stdout]    |              ^^ expected enum `Result`, found `()`
[INFO] [stdout]    |
[INFO] [stdout]    = note:   expected enum `Result<(), std::io::Error>`
[INFO] [stdout]            found unit type `()`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0308.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]   --> jtool/src/main.rs:10:13
[INFO] [stdout]    |
[INFO] [stdout] 1  |   pub fn process(v: &mut json::Value) -> std::io::Result<()> {
[INFO] [stdout]    |                                          ------------------- expected `Result<(), std::io::Error>` because of return type
[INFO] [stdout] ...
[INFO] [stdout] 10 | /             obj.iter_mut().for_each(|(k,v)| {
[INFO] [stdout] 11 | |                 process(v);
[INFO] [stdout] 12 | |             })
[INFO] [stdout]    | |______________^ expected enum `Result`, found `()`
[INFO] [stdout]    |
[INFO] [stdout]    = note:   expected enum `Result<(), std::io::Error>`
[INFO] [stdout]            found unit type `()`
[INFO] [stdout] help: try using a variant of the expected enum
[INFO] [stdout]    |
[INFO] [stdout] 10 ~             Ok(obj.iter_mut().for_each(|(k,v)| {
[INFO] [stdout] 11 +                 process(v);
[INFO] [stdout] 12 +             }))
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]   --> jtool/src/main.rs:14:14
[INFO] [stdout]    |
[INFO] [stdout] 14 |         _ => {}
[INFO] [stdout]    |              ^^ expected enum `Result`, found `()`
[INFO] [stdout]    |
[INFO] [stdout]    = note:   expected enum `Result<(), std::io::Error>`
[INFO] [stdout]            found unit type `()`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0308.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `jtool` due to 5 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: `extern` fn uses type `str`, which is not FFI-safe
[INFO] [stdout]    --> upcache/src/cache/mod.rs:392:30
[INFO] [stdout]     |
[INFO] [stdout] 392 | pub extern "C" fn load(name: &str) -> Result<Cache> {
[INFO] [stdout]     |                              ^^^^ not FFI-safe
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(improper_ctypes_definitions)]` on by default
[INFO] [stdout]     = help: consider using `*const u8` and a length instead
[INFO] [stdout]     = note: string slices have no C equivalent
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `extern` fn uses type `std::result::Result<Cache, Box<dyn StdError>>`, which is not FFI-safe
[INFO] [stdout]    --> upcache/src/cache/mod.rs:392:39
[INFO] [stdout]     |
[INFO] [stdout] 392 | pub extern "C" fn load(name: &str) -> Result<Cache> {
[INFO] [stdout]     |                                       ^^^^^^^^^^^^^ not FFI-safe
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stdout]     = note: enum has no representation hint
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `extern` fn uses type `str`, which is not FFI-safe
[INFO] [stdout]    --> upcache/src/cache/mod.rs:392:30
[INFO] [stdout]     |
[INFO] [stdout] 392 | pub extern "C" fn load(name: &str) -> Result<Cache> {
[INFO] [stdout]     |                              ^^^^ not FFI-safe
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(improper_ctypes_definitions)]` on by default
[INFO] [stdout]     = help: consider using `*const u8` and a length instead
[INFO] [stdout]     = note: string slices have no C equivalent
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `extern` fn uses type `std::result::Result<Cache, Box<dyn StdError>>`, which is not FFI-safe
[INFO] [stdout]    --> upcache/src/cache/mod.rs:392:39
[INFO] [stdout]     |
[INFO] [stdout] 392 | pub extern "C" fn load(name: &str) -> Result<Cache> {
[INFO] [stdout]     |                                       ^^^^^^^^^^^^^ not FFI-safe
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stdout]     = note: enum has no representation hint
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "20f94d0299da284f3482a535f3821bcf8d21c22e850bf30ee0b49aebf5eb4537", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "20f94d0299da284f3482a535f3821bcf8d21c22e850bf30ee0b49aebf5eb4537", kill_on_drop: false }`
[INFO] [stdout] 20f94d0299da284f3482a535f3821bcf8d21c22e850bf30ee0b49aebf5eb4537
