[INFO] fetching crate serde-json-helpers 0.1.2...
[INFO] checking serde-json-helpers-0.1.2 against try#cac44d9528e3bbbdaa1537d187bd489ccc5de18c for pr-91141
[INFO] extracting crate serde-json-helpers 0.1.2 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate serde-json-helpers 0.1.2 on toolchain cac44d9528e3bbbdaa1537d187bd489ccc5de18c
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate serde-json-helpers 0.1.2
[INFO] finished tweaking crates.io crate serde-json-helpers 0.1.2
[INFO] tweaked toml for crates.io crate serde-json-helpers 0.1.2 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 458a700d0b1bb6f227d6ffdf82d68390491662c927fc0f1a3d5e9f797c1767da
[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" "458a700d0b1bb6f227d6ffdf82d68390491662c927fc0f1a3d5e9f797c1767da", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "458a700d0b1bb6f227d6ffdf82d68390491662c927fc0f1a3d5e9f797c1767da", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "458a700d0b1bb6f227d6ffdf82d68390491662c927fc0f1a3d5e9f797c1767da", kill_on_drop: false }`
[INFO] [stdout] 458a700d0b1bb6f227d6ffdf82d68390491662c927fc0f1a3d5e9f797c1767da
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 81586c274010483dd28f8d83feb4ab56f1f763f1202e82ad6d26478b46c4214a
[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" "81586c274010483dd28f8d83feb4ab56f1f763f1202e82ad6d26478b46c4214a", kill_on_drop: false }`
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling serde v1.0.130
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking unicode-xid v0.1.0
[INFO] [stderr]    Compiling ryu v1.0.6
[INFO] [stderr]    Compiling serde_json v1.0.72
[INFO] [stderr]     Checking itoa v0.4.8
[INFO] [stderr]    Compiling proc-macro2 v1.0.32
[INFO] [stderr]    Compiling quote v1.0.10
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]    Compiling syn v1.0.82
[INFO] [stderr]    Compiling serde_derive v1.0.130
[INFO] [stderr]     Checking serde-json-helpers v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `str::<impl str>::to_ascii_uppercase` that must be used
[INFO] [stdout]   --> src/string_transform.rs:99:21
[INFO] [stdout]    |
[INFO] [stdout] 99 |                     s.to_ascii_uppercase();
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: to uppercase the value in-place, use `make_ascii_uppercase()`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `str::<impl str>::to_ascii_lowercase` that must be used
[INFO] [stdout]    --> src/string_transform.rs:115:13
[INFO] [stdout]     |
[INFO] [stdout] 115 |             s.to_ascii_lowercase();
[INFO] [stdout]     |             ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: to lowercase the value in-place, use `make_ascii_lowercase()`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `str::<impl str>::to_ascii_uppercase` that must be used
[INFO] [stdout]   --> src/string_transform.rs:99:21
[INFO] [stdout]    |
[INFO] [stdout] 99 |                     s.to_ascii_uppercase();
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: to uppercase the value in-place, use `make_ascii_uppercase()`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `str::<impl str>::to_ascii_lowercase` that must be used
[INFO] [stdout]    --> src/string_transform.rs:115:13
[INFO] [stdout]     |
[INFO] [stdout] 115 |             s.to_ascii_lowercase();
[INFO] [stdout]     |             ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: to lowercase the value in-place, use `make_ascii_lowercase()`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `str::<impl str>::to_ascii_uppercase` that must be used
[INFO] [stdout]   --> src/string_transform.rs:99:21
[INFO] [stdout]    |
[INFO] [stdout] 99 |                     s.to_ascii_uppercase();
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: to uppercase the value in-place, use `make_ascii_uppercase()`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `str::<impl str>::to_ascii_lowercase` that must be used
[INFO] [stdout]    --> src/string_transform.rs:115:13
[INFO] [stdout]     |
[INFO] [stdout] 115 |             s.to_ascii_lowercase();
[INFO] [stdout]     |             ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: to lowercase the value in-place, use `make_ascii_lowercase()`
[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 45.51s
[INFO] running `Command { std: "docker" "inspect" "81586c274010483dd28f8d83feb4ab56f1f763f1202e82ad6d26478b46c4214a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "81586c274010483dd28f8d83feb4ab56f1f763f1202e82ad6d26478b46c4214a", kill_on_drop: false }`
[INFO] [stdout] 81586c274010483dd28f8d83feb4ab56f1f763f1202e82ad6d26478b46c4214a