[INFO] cloning repository https://github.com/AHSPONTES/building_a_library
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/AHSPONTES/building_a_library" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAHSPONTES%2Fbuilding_a_library", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAHSPONTES%2Fbuilding_a_library'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] b4e81747aa8b98ed4e5a47105b60e9f82cca14ca
[INFO] checking AHSPONTES/building_a_library against master#c90bcb9571b7aab0d8beaa2ce8a998ffaf079d38 for pr-146470
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAHSPONTES%2Fbuilding_a_library" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/AHSPONTES/building_a_library
[INFO] finished tweaking git repo https://github.com/AHSPONTES/building_a_library
[INFO] tweaked toml for git repo https://github.com/AHSPONTES/building_a_library written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/AHSPONTES/building_a_library on toolchain c90bcb9571b7aab0d8beaa2ce8a998ffaf079d38
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+c90bcb9571b7aab0d8beaa2ce8a998ffaf079d38" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/AHSPONTES/building_a_library 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" "+c90bcb9571b7aab0d8beaa2ce8a998ffaf079d38" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded itoa v0.4.7
[INFO] [stderr]   Downloaded serde_derive v1.0.126
[INFO] [stderr]   Downloaded ryu v1.0.5
[INFO] [stderr]   Downloaded proc-macro2 v1.0.27
[INFO] [stderr]   Downloaded syn v1.0.73
[INFO] [stderr]   Downloaded serde v1.0.126
[INFO] [stderr]   Downloaded quote v1.0.9
[INFO] [stderr]   Downloaded serde_json v1.0.64
[INFO] [stderr]   Downloaded unicode-xid v0.2.2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+c90bcb9571b7aab0d8beaa2ce8a998ffaf079d38" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] bd8af3daede28a238e5457ceea3ad603c1bbdf00852318b0ea6c53c72b5f49a4
[INFO] running `Command { std: "docker" "start" "-a" "bd8af3daede28a238e5457ceea3ad603c1bbdf00852318b0ea6c53c72b5f49a4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bd8af3daede28a238e5457ceea3ad603c1bbdf00852318b0ea6c53c72b5f49a4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bd8af3daede28a238e5457ceea3ad603c1bbdf00852318b0ea6c53c72b5f49a4", kill_on_drop: false }`
[INFO] [stdout] bd8af3daede28a238e5457ceea3ad603c1bbdf00852318b0ea6c53c72b5f49a4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+c90bcb9571b7aab0d8beaa2ce8a998ffaf079d38" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f95413ac0dbf0ad249841937e3178c9c12e15b957bd54c77dcf583cac05d67e0
[INFO] running `Command { std: "docker" "start" "-a" "f95413ac0dbf0ad249841937e3178c9c12e15b957bd54c77dcf583cac05d67e0", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.27
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling syn v1.0.73
[INFO] [stderr]    Compiling serde_derive v1.0.126
[INFO] [stderr]    Compiling serde v1.0.126
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]    Compiling serde_json v1.0.64
[INFO] [stderr]     Checking itoa v0.4.7
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]     Checking building_a_library v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `serde_json::Result`
[INFO] [stdout]  --> src/main.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use serde_json::Result;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `serde_json::Result`
[INFO] [stdout]  --> src/main.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use serde_json::Result;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:27:5
[INFO] [stdout]    |
[INFO] [stdout] 27 |     serde_json::to_writer(file, &d);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let _ = serde_json::to_writer(file, &d);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:27:5
[INFO] [stdout]    |
[INFO] [stdout] 27 |     serde_json::to_writer(file, &d);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let _ = serde_json::to_writer(file, &d);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 6.27s
[INFO] running `Command { std: "docker" "inspect" "f95413ac0dbf0ad249841937e3178c9c12e15b957bd54c77dcf583cac05d67e0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f95413ac0dbf0ad249841937e3178c9c12e15b957bd54c77dcf583cac05d67e0", kill_on_drop: false }`
[INFO] [stdout] f95413ac0dbf0ad249841937e3178c9c12e15b957bd54c77dcf583cac05d67e0
