[INFO] fetching crate ent 0.0.4...
[INFO] checking ent-0.0.4 against master#31ee872db5aae4750e3da1ca4ed1523c4356947f for pr-78461
[INFO] extracting crate ent 0.0.4 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate ent 0.0.4 on toolchain 31ee872db5aae4750e3da1ca4ed1523c4356947f
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+31ee872db5aae4750e3da1ca4ed1523c4356947f" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate ent 0.0.4
[INFO] finished tweaking crates.io crate ent 0.0.4
[INFO] tweaked toml for crates.io crate ent 0.0.4 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+31ee872db5aae4750e3da1ca4ed1523c4356947f" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+31ee872db5aae4750e3da1ca4ed1523c4356947f" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+31ee872db5aae4750e3da1ca4ed1523c4356947f" "metadata" "--no-deps" "--format-version=1", 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] 07e6b5e436500a20098fa239d3ddbd5c220b6f2f8493c7fb956681152bc468df
[INFO] running `Command { std: "docker" "start" "-a" "07e6b5e436500a20098fa239d3ddbd5c220b6f2f8493c7fb956681152bc468df", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "07e6b5e436500a20098fa239d3ddbd5c220b6f2f8493c7fb956681152bc468df", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "07e6b5e436500a20098fa239d3ddbd5c220b6f2f8493c7fb956681152bc468df", kill_on_drop: false }`
[INFO] [stdout] 07e6b5e436500a20098fa239d3ddbd5c220b6f2f8493c7fb956681152bc468df
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+31ee872db5aae4750e3da1ca4ed1523c4356947f" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 98eaa86cd5ac0c2639958d4e91d1b04aae3be7a4273a233daa4506299c4ab2f3
[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" "98eaa86cd5ac0c2639958d4e91d1b04aae3be7a4273a233daa4506299c4ab2f3", kill_on_drop: false }`
[INFO] [stderr]     Checking ent v0.0.4 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared crate or module `serde_json`
[INFO] [stdout]   --> tests/basic.rs:10:12
[INFO] [stdout]    |
[INFO] [stdout] 10 |     let v: serde_json::Value = serde_json::from_str(r#"{"name":"test"}"#).unwrap();
[INFO] [stdout]    |            ^^^^^^^^^^ use of undeclared crate or module `serde_json`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared crate or module `serde_json`
[INFO] [stdout]   --> tests/basic.rs:10:32
[INFO] [stdout]    |
[INFO] [stdout] 10 |     let v: serde_json::Value = serde_json::from_str(r#"{"name":"test"}"#).unwrap();
[INFO] [stdout]    |                                ^^^^^^^^^^ use of undeclared crate or module `serde_json`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0433`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `ent`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "98eaa86cd5ac0c2639958d4e91d1b04aae3be7a4273a233daa4506299c4ab2f3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "98eaa86cd5ac0c2639958d4e91d1b04aae3be7a4273a233daa4506299c4ab2f3", kill_on_drop: false }`
[INFO] [stdout] 98eaa86cd5ac0c2639958d4e91d1b04aae3be7a4273a233daa4506299c4ab2f3