[INFO] cloning repository https://github.com/Basharkhan7776/rustling
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Basharkhan7776/rustling" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FBasharkhan7776%2Frustling", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FBasharkhan7776%2Frustling'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 3faf47afa812ec54f141871d32adb525e0e2d602
[INFO] checking Basharkhan7776/rustling against master#da2544bfbe84df7b24d83c029c74299ebf6112c6 for pr-149681
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FBasharkhan7776%2Frustling" "/workspace/builds/worker-5-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/Basharkhan7776/rustling
[INFO] finished tweaking git repo https://github.com/Basharkhan7776/rustling
[INFO] tweaked toml for git repo https://github.com/Basharkhan7776/rustling written to /workspace/builds/worker-5-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/Basharkhan7776/rustling on toolchain da2544bfbe84df7b24d83c029c74299ebf6112c6
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+da2544bfbe84df7b24d83c029c74299ebf6112c6" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/Basharkhan7776/rustling already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+da2544bfbe84df7b24d83c029c74299ebf6112c6" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/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@sha256:845e597a41426bbf2703be69acdb67d10b6de511142d05cba7bbe119c898b2c7" "/opt/rustwide/cargo-home/bin/cargo" "+da2544bfbe84df7b24d83c029c74299ebf6112c6" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8e35b3c33aa7b3142fde89bbafdcfd9a82ba8a23ea2777f2d452c7e459898f8c
[INFO] running `Command { std: "docker" "start" "-a" "8e35b3c33aa7b3142fde89bbafdcfd9a82ba8a23ea2777f2d452c7e459898f8c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8e35b3c33aa7b3142fde89bbafdcfd9a82ba8a23ea2777f2d452c7e459898f8c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8e35b3c33aa7b3142fde89bbafdcfd9a82ba8a23ea2777f2d452c7e459898f8c", kill_on_drop: false }`
[INFO] [stdout] 8e35b3c33aa7b3142fde89bbafdcfd9a82ba8a23ea2777f2d452c7e459898f8c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/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=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-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@sha256:845e597a41426bbf2703be69acdb67d10b6de511142d05cba7bbe119c898b2c7" "/opt/rustwide/cargo-home/bin/cargo" "+da2544bfbe84df7b24d83c029c74299ebf6112c6" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8fbfa15143f5887e6728955d1083487bead552d7c3910db396e8e7d295d3476c
[INFO] running `Command { std: "docker" "start" "-a" "8fbfa15143f5887e6728955d1083487bead552d7c3910db396e8e7d295d3476c", kill_on_drop: false }`
[INFO] [stderr]     Checking exercises v0.0.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]   --> exercises/13_error_handling/errors3.rs:23:46
[INFO] [stdout]    |
[INFO] [stdout] 18 | fn main() {
[INFO] [stdout]    | --------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 23 |     let cost = total_cost(pretend_user_input)?;
[INFO] [stdout]    |                                              ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout] 18 | fn main() -> Result<(), Box<dyn std::error::Error>> {
[INFO] [stdout]    |           +++++++++++++++++++++++++++++++++++++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]   --> exercises/13_error_handling/errors5.rs:53:44
[INFO] [stdout]    |
[INFO] [stdout] 51 | fn main() {
[INFO] [stdout]    | --------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] 52 |     let pretend_user_input = "42";
[INFO] [stdout] 53 |     let x: i64 = pretend_user_input.parse()?;
[INFO] [stdout]    |                                            ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout] 51 | fn main() -> Result<(), Box<dyn std::error::Error>> {
[INFO] [stdout]    |           +++++++++++++++++++++++++++++++++++++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]   --> exercises/13_error_handling/errors5.rs:54:59
[INFO] [stdout]    |
[INFO] [stdout] 51 | fn main() {
[INFO] [stdout]    | --------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 54 |     println!("output={:?}", PositiveNonzeroInteger::new(x)?);
[INFO] [stdout]    |                                                           ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout] 51 | fn main() -> Result<(), Box<dyn std::error::Error>> {
[INFO] [stdout]    |           +++++++++++++++++++++++++++++++++++++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]   --> exercises/13_error_handling/errors5.rs:55:5
[INFO] [stdout]    |
[INFO] [stdout] 51 | fn main() {
[INFO] [stdout]    |          - expected `()` because of default return type
[INFO] [stdout] ...
[INFO] [stdout] 55 |     Ok(())
[INFO] [stdout]    |     ^^^^^^ expected `()`, found `Result<(), _>`
[INFO] [stdout]    |
[INFO] [stdout]    = note: expected unit type `()`
[INFO] [stdout]                    found enum `Result<(), _>`
[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 `exercises` (bin "errors5") due to 3 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: could not compile `exercises` (bin "errors3") due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "8fbfa15143f5887e6728955d1083487bead552d7c3910db396e8e7d295d3476c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8fbfa15143f5887e6728955d1083487bead552d7c3910db396e8e7d295d3476c", kill_on_drop: false }`
[INFO] [stdout] 8fbfa15143f5887e6728955d1083487bead552d7c3910db396e8e7d295d3476c
