[INFO] cloning repository https://github.com/prowe/rust_guessing_game
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/prowe/rust_guessing_game" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fprowe%2Frust_guessing_game", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fprowe%2Frust_guessing_game'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1758a22df4bc58622ae526b8dc6b8d5102aabfa2
[INFO] testing prowe/rust_guessing_game against 1.54.0 for beta-1.55-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fprowe%2Frust_guessing_game" "/workspace/builds/worker-22/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-22/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/prowe/rust_guessing_game on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/prowe/rust_guessing_game
[INFO] finished tweaking git repo https://github.com/prowe/rust_guessing_game
[INFO] tweaked toml for git repo https://github.com/prowe/rust_guessing_game written to /workspace/builds/worker-22/source/Cargo.toml
[INFO] crate git repo https://github.com/prowe/rust_guessing_game already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "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-22/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-22/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 96417b2d4189acb2e34b0b42c71868918318a777289a88d8ef9c5d31ae24793d
[INFO] running `Command { std: "docker" "start" "-a" "96417b2d4189acb2e34b0b42c71868918318a777289a88d8ef9c5d31ae24793d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "96417b2d4189acb2e34b0b42c71868918318a777289a88d8ef9c5d31ae24793d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "96417b2d4189acb2e34b0b42c71868918318a777289a88d8ef9c5d31ae24793d", kill_on_drop: false }`
[INFO] [stdout] 96417b2d4189acb2e34b0b42c71868918318a777289a88d8ef9c5d31ae24793d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-22/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-22/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f12336056937f3ddfbcb695283b16f84ffb09a2602699de66290d3d264f543eb
[INFO] running `Command { std: "docker" "start" "-a" "f12336056937f3ddfbcb695283b16f84ffb09a2602699de66290d3d264f543eb", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.28
[INFO] [stderr]    Compiling rand v0.3.16
[INFO] [stderr]    Compiling guessing_game v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::result`
[INFO] [stdout]  --> src/main.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use std::result;
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:29:32
[INFO] [stdout]    |
[INFO] [stdout] 29 | fn read_guess() -> Result<u32, Error> {
[INFO] [stdout]    |                                ^^^^^ help: use `dyn`: `dyn Error`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2021 edition!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the size for values of type `(dyn std::error::Error + 'static)` cannot be known at compilation time
[INFO] [stdout]    --> src/main.rs:29:20
[INFO] [stdout]     |
[INFO] [stdout] 29  | fn read_guess() -> Result<u32, Error> {
[INFO] [stdout]     |                    ^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
[INFO] [stdout]     |
[INFO] [stdout]     = help: the trait `Sized` is not implemented for `(dyn std::error::Error + 'static)`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `guessing_game`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "f12336056937f3ddfbcb695283b16f84ffb09a2602699de66290d3d264f543eb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f12336056937f3ddfbcb695283b16f84ffb09a2602699de66290d3d264f543eb", kill_on_drop: false }`
[INFO] [stdout] f12336056937f3ddfbcb695283b16f84ffb09a2602699de66290d3d264f543eb
