[INFO] cloning repository https://github.com/jit-y/diff_json
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/jit-y/diff_json" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjit-y%2Fdiff_json", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjit-y%2Fdiff_json'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 71764bdfc8d7f81964338b529e508948d93029d0
[INFO] checking jit-y/diff_json against master#5e3f1b148db5bfa27fee52464ae1f5d34c49d77b for pr-75502
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjit-y%2Fdiff_json" "/workspace/builds/worker-9/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-9/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/jit-y/diff_json on toolchain 5e3f1b148db5bfa27fee52464ae1f5d34c49d77b
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5e3f1b148db5bfa27fee52464ae1f5d34c49d77b" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/jit-y/diff_json
[INFO] finished tweaking git repo https://github.com/jit-y/diff_json
[INFO] tweaked toml for git repo https://github.com/jit-y/diff_json written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] crate git repo https://github.com/jit-y/diff_json already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5e3f1b148db5bfa27fee52464ae1f5d34c49d77b" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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:e18d859f9e32a1da89bc7b2d7d51e13b57342044d1295d9fc0dd0068c58eb3d1" "/opt/rustwide/cargo-home/bin/cargo" "+5e3f1b148db5bfa27fee52464ae1f5d34c49d77b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4d2798302027886756f2731ce8e270935a3ad26370f6dc6d392e696eab1c2ff0
[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" "4d2798302027886756f2731ce8e270935a3ad26370f6dc6d392e696eab1c2ff0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4d2798302027886756f2731ce8e270935a3ad26370f6dc6d392e696eab1c2ff0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4d2798302027886756f2731ce8e270935a3ad26370f6dc6d392e696eab1c2ff0", kill_on_drop: false }`
[INFO] [stdout] 4d2798302027886756f2731ce8e270935a3ad26370f6dc6d392e696eab1c2ff0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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:e18d859f9e32a1da89bc7b2d7d51e13b57342044d1295d9fc0dd0068c58eb3d1" "/opt/rustwide/cargo-home/bin/cargo" "+5e3f1b148db5bfa27fee52464ae1f5d34c49d77b" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 78099bd89c418f926e52c1c6ec6de7f1bbd6c224933f27b182f62c04d660be47
[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" "78099bd89c418f926e52c1c6ec6de7f1bbd6c224933f27b182f62c04d660be47", kill_on_drop: false }`
[INFO] [stderr]     Checking itoa v0.3.4
[INFO] [stderr]     Checking serde v1.0.27
[INFO] [stderr]     Checking difference v1.0.0
[INFO] [stderr]     Checking serde_json v1.0.9
[INFO] [stderr]     Checking diff_json v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: struct is never constructed: `JSONPrettier`
[INFO] [stdout]  --> src/prettier.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 4 | struct JSONPrettier {
[INFO] [stdout]   |        ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `to_pretty`
[INFO] [stdout]  --> src/prettier.rs:9:12
[INFO] [stdout]   |
[INFO] [stdout] 9 |     pub fn to_pretty() {
[INFO] [stdout]   |            ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `JSONPrettier`
[INFO] [stdout]  --> src/prettier.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 4 | struct JSONPrettier {
[INFO] [stdout]   |        ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `to_pretty`
[INFO] [stdout]  --> src/prettier.rs:9:12
[INFO] [stdout]   |
[INFO] [stdout] 9 |     pub fn to_pretty() {
[INFO] [stdout]   |            ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 8.86s
[INFO] running `Command { std: "docker" "inspect" "78099bd89c418f926e52c1c6ec6de7f1bbd6c224933f27b182f62c04d660be47", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "78099bd89c418f926e52c1c6ec6de7f1bbd6c224933f27b182f62c04d660be47", kill_on_drop: false }`
[INFO] [stdout] 78099bd89c418f926e52c1c6ec6de7f1bbd6c224933f27b182f62c04d660be47