[INFO] fetching crate wxf-converter 0.3.0...
[INFO] checking wxf-converter-0.3.0 against 1.55.0 for beta-1.56-3
[INFO] extracting crate wxf-converter 0.3.0 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate wxf-converter 0.3.0 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate wxf-converter 0.3.0
[INFO] finished tweaking crates.io crate wxf-converter 0.3.0
[INFO] tweaked toml for crates.io crate wxf-converter 0.3.0 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate crates.io crate wxf-converter 0.3.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded iter-read v0.2.1
[INFO] [stderr]   Downloaded wolfram_wxf v0.2.2
[INFO] [stderr]   Downloaded serde-pickle v0.6.0
[INFO] [stderr]   Downloaded clap v2.27.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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_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" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 719c1b5c937bbaf599fafab6b3d006c1563bea1b2f316ea7cbd1ca4f408e7053
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "719c1b5c937bbaf599fafab6b3d006c1563bea1b2f316ea7cbd1ca4f408e7053", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "719c1b5c937bbaf599fafab6b3d006c1563bea1b2f316ea7cbd1ca4f408e7053", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "719c1b5c937bbaf599fafab6b3d006c1563bea1b2f316ea7cbd1ca4f408e7053", kill_on_drop: false }`
[INFO] [stdout] 719c1b5c937bbaf599fafab6b3d006c1563bea1b2f316ea7cbd1ca4f408e7053
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "+1.55.0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] eabb1e4b391ab65e2f80b143d35bfcabc29cad97305613c55f276cdf59ead9a1
[INFO] running `Command { std: "docker" "start" "-a" "eabb1e4b391ab65e2f80b143d35bfcabc29cad97305613c55f276cdf59ead9a1", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde v1.0.105
[INFO] [stderr]     Checking iter-read v0.2.1
[INFO] [stderr]    Compiling num-bigint v0.2.6
[INFO] [stderr]    Compiling num-rational v0.2.4
[INFO] [stderr]     Checking textwrap v0.9.0
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking flate2 v1.0.14
[INFO] [stderr]     Checking clap v2.27.1
[INFO] [stderr]     Checking num v0.2.1
[INFO] [stderr]     Checking serde_json v1.0.48
[INFO] [stderr]     Checking serde-pickle v0.6.0
[INFO] [stderr]     Checking wolfram_wxf v0.2.2
[INFO] [stderr]     Checking wxf-converter v0.3.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0412]: cannot find type `NoneError` in module `std::option`
[INFO] [stdout]   --> src/utils.rs:46:24
[INFO] [stdout]    |
[INFO] [stdout] 46 | impl From<std::option::NoneError> for Error {
[INFO] [stdout]    |                        ^^^^^^^^^ not found in `std::option`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0412]: cannot find type `NoneError` in module `std::option`
[INFO] [stdout]   --> src/utils.rs:47:29
[INFO] [stdout]    |
[INFO] [stdout] 47 |     fn from(_: std::option::NoneError) -> Self {
[INFO] [stdout]    |                             ^^^^^^^^^ not found in `std::option`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(try_trait)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0412]: cannot find type `NoneError` in module `std::option`
[INFO] [stdout]   --> src/utils.rs:46:24
[INFO] [stdout]    |
[INFO] [stdout] 46 | impl From<std::option::NoneError> for Error {
[INFO] [stdout]    |                        ^^^^^^^^^ not found in `std::option`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0412]: cannot find type `NoneError` in module `std::option`
[INFO] [stdout]   --> src/utils.rs:47:29
[INFO] [stdout]    |
[INFO] [stdout] 47 |     fn from(_: std::option::NoneError) -> Self {
[INFO] [stdout]    |                             ^^^^^^^^^ not found in `std::option`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(try_trait)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used on `Result`s, not `Option`s, in a function that returns `Result`
[INFO] [stdout]    --> src/utils.rs:13:39
[INFO] [stdout]     |
[INFO] [stdout] 9   | / pub fn parse_file(path: &str, format: Option<&str>) -> Result<WolframValue, Error> {
[INFO] [stdout] 10  | |     let s = fs::read_to_string(path)?;
[INFO] [stdout] 11  | |     let suffix = match format {
[INFO] [stdout] 12  | |         Some(s) => s,
[INFO] [stdout] 13  | |         None => path.split('/').last()?.split('.').last()?,
[INFO] [stdout]     | |                                       ^ use `.ok_or(...)?` to provide an error compatible with `Result<WolframValue, Error>`
[INFO] [stdout] ...   |
[INFO] [stdout] 26  | |     }
[INFO] [stdout] 27  | | }
[INFO] [stdout]     | |_- this function returns a `Result`
[INFO] [stdout]     |
[INFO] [stdout]     = help: the trait `FromResidual<Option<Infallible>>` is not implemented for `Result<WolframValue, Error>`
[INFO] [stdout] note: required by `from_residual`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used on `Result`s, not `Option`s, in a function that returns `Result`
[INFO] [stdout]    --> src/utils.rs:13:58
[INFO] [stdout]     |
[INFO] [stdout] 9   | / pub fn parse_file(path: &str, format: Option<&str>) -> Result<WolframValue, Error> {
[INFO] [stdout] 10  | |     let s = fs::read_to_string(path)?;
[INFO] [stdout] 11  | |     let suffix = match format {
[INFO] [stdout] 12  | |         Some(s) => s,
[INFO] [stdout] 13  | |         None => path.split('/').last()?.split('.').last()?,
[INFO] [stdout]     | |                                                          ^ use `.ok_or(...)?` to provide an error compatible with `Result<WolframValue, Error>`
[INFO] [stdout] ...   |
[INFO] [stdout] 26  | |     }
[INFO] [stdout] 27  | | }
[INFO] [stdout]     | |_- this function returns a `Result`
[INFO] [stdout]     |
[INFO] [stdout]     = help: the trait `FromResidual<Option<Infallible>>` is not implemented for `Result<WolframValue, Error>`
[INFO] [stdout] note: required by `from_residual`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 5 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0412, E0554.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `wxf-converter` due to 6 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error[E0277]: the `?` operator can only be used on `Result`s, not `Option`s, in a function that returns `Result`
[INFO] [stdout]    --> src/utils.rs:13:39
[INFO] [stdout]     |
[INFO] [stdout] 9   | / pub fn parse_file(path: &str, format: Option<&str>) -> Result<WolframValue, Error> {
[INFO] [stdout] 10  | |     let s = fs::read_to_string(path)?;
[INFO] [stdout] 11  | |     let suffix = match format {
[INFO] [stdout] 12  | |         Some(s) => s,
[INFO] [stdout] 13  | |         None => path.split('/').last()?.split('.').last()?,
[INFO] [stdout]     | |                                       ^ use `.ok_or(...)?` to provide an error compatible with `Result<WolframValue, Error>`
[INFO] [stdout] ...   |
[INFO] [stdout] 26  | |     }
[INFO] [stdout] 27  | | }
[INFO] [stdout]     | |_- this function returns a `Result`
[INFO] [stdout]     |
[INFO] [stdout]     = help: the trait `FromResidual<Option<Infallible>>` is not implemented for `Result<WolframValue, Error>`
[INFO] [stdout] note: required by `from_residual`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used on `Result`s, not `Option`s, in a function that returns `Result`
[INFO] [stdout]    --> src/utils.rs:13:58
[INFO] [stdout]     |
[INFO] [stdout] 9   | / pub fn parse_file(path: &str, format: Option<&str>) -> Result<WolframValue, Error> {
[INFO] [stdout] 10  | |     let s = fs::read_to_string(path)?;
[INFO] [stdout] 11  | |     let suffix = match format {
[INFO] [stdout] 12  | |         Some(s) => s,
[INFO] [stdout] 13  | |         None => path.split('/').last()?.split('.').last()?,
[INFO] [stdout]     | |                                                          ^ use `.ok_or(...)?` to provide an error compatible with `Result<WolframValue, Error>`
[INFO] [stdout] ...   |
[INFO] [stdout] 26  | |     }
[INFO] [stdout] 27  | | }
[INFO] [stdout]     | |_- this function returns a `Result`
[INFO] [stdout]     |
[INFO] [stdout]     = help: the trait `FromResidual<Option<Infallible>>` is not implemented for `Result<WolframValue, Error>`
[INFO] [stdout] note: required by `from_residual`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 5 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0412, E0554.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "eabb1e4b391ab65e2f80b143d35bfcabc29cad97305613c55f276cdf59ead9a1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "eabb1e4b391ab65e2f80b143d35bfcabc29cad97305613c55f276cdf59ead9a1", kill_on_drop: false }`
[INFO] [stdout] eabb1e4b391ab65e2f80b143d35bfcabc29cad97305613c55f276cdf59ead9a1
