[INFO] fetching crate polars-io 0.15.1...
[INFO] testing polars-io-0.15.1 against 1.55.0 for beta-1.56-1
[INFO] extracting crate polars-io 0.15.1 into /workspace/builds/worker-87/source
[INFO] validating manifest of crates.io crate polars-io 0.15.1 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate polars-io 0.15.1
[INFO] finished tweaking crates.io crate polars-io 0.15.1
[INFO] tweaked toml for crates.io crate polars-io 0.15.1 written to /workspace/builds/worker-87/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-87/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-87/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5cc9ef27c4b55faffd4e91f61b65530f3b0644d1786c5d68632d7bfdde9766ec
[INFO] running `Command { std: "docker" "start" "-a" "5cc9ef27c4b55faffd4e91f61b65530f3b0644d1786c5d68632d7bfdde9766ec", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5cc9ef27c4b55faffd4e91f61b65530f3b0644d1786c5d68632d7bfdde9766ec", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5cc9ef27c4b55faffd4e91f61b65530f3b0644d1786c5d68632d7bfdde9766ec", kill_on_drop: false }`
[INFO] [stdout] 5cc9ef27c4b55faffd4e91f61b65530f3b0644d1786c5d68632d7bfdde9766ec
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-87/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-87/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] cadea2dc870c497c95903c01fe29669938a732ba29250f8c637e2004935cad11
[INFO] running `Command { std: "docker" "start" "-a" "cadea2dc870c497c95903c01fe29669938a732ba29250f8c637e2004935cad11", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling libc v0.2.101
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling crossbeam-utils v0.8.5
[INFO] [stderr]    Compiling proc-macro2 v1.0.29
[INFO] [stderr]    Compiling lazy_static v1.4.0
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.5
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling rayon-core v1.9.1
[INFO] [stderr]    Compiling scopeguard v1.1.0
[INFO] [stderr]    Compiling syn v1.0.76
[INFO] [stderr]    Compiling version_check v0.9.3
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]    Compiling once_cell v1.8.0
[INFO] [stderr]    Compiling memchr v2.4.1
[INFO] [stderr]    Compiling serde v1.0.130
[INFO] [stderr]    Compiling lexical-core v0.7.6
[INFO] [stderr]    Compiling serde_derive v1.0.130
[INFO] [stderr]    Compiling serde_json v1.0.67
[INFO] [stderr]    Compiling bitflags v1.3.2
[INFO] [stderr]    Compiling itoa v0.4.8
[INFO] [stderr]    Compiling static_assertions v1.1.0
[INFO] [stderr]    Compiling regex-syntax v0.6.25
[INFO] [stderr]    Compiling arrayvec v0.5.2
[INFO] [stderr]    Compiling rand_core v0.6.3
[INFO] [stderr]    Compiling hex v0.4.3
[INFO] [stderr]    Compiling anyhow v1.0.43
[INFO] [stderr]    Compiling unsafe_unwrap v0.1.0
[INFO] [stderr]    Compiling itertools v0.10.1
[INFO] [stderr]    Compiling rand v0.8.4
[INFO] [stderr]    Compiling memoffset v0.6.4
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling rayon v1.5.1
[INFO] [stderr]    Compiling num-bigint v0.4.2
[INFO] [stderr]    Compiling num-rational v0.4.0
[INFO] [stderr]    Compiling num-iter v0.1.42
[INFO] [stderr]    Compiling indexmap v1.7.0
[INFO] [stderr]    Compiling ahash v0.7.4
[INFO] [stderr]    Compiling crossbeam-channel v0.5.1
[INFO] [stderr]    Compiling aho-corasick v0.7.18
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling getrandom v0.2.3
[INFO] [stderr]    Compiling time v0.1.43
[INFO] [stderr]    Compiling dirs-sys v0.3.6
[INFO] [stderr]    Compiling crossbeam-deque v0.8.1
[INFO] [stderr]    Compiling dirs v3.0.2
[INFO] [stderr]    Compiling num-complex v0.4.0
[INFO] [stderr]    Compiling chrono v0.4.19
[INFO] [stderr]    Compiling regex v1.5.4
[INFO] [stderr]    Compiling num v0.4.0
[INFO] [stderr]    Compiling hashbrown v0.11.2
[INFO] [stderr]    Compiling multiversion-macros v0.6.1
[INFO] [stderr]    Compiling thiserror-impl v1.0.29
[INFO] [stderr]    Compiling multiversion v0.6.1
[INFO] [stderr]    Compiling thiserror v1.0.29
[INFO] [stderr]    Compiling arrow v5.3.0
[INFO] [stderr]    Compiling polars-arrow v0.15.1
[INFO] [stderr]    Compiling polars-core v0.15.1
[INFO] [stderr]    Compiling polars-io v0.15.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: function is never used: `to_arrow_compatible_df`
[INFO] [stdout]  --> src/utils.rs:5:15
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub(crate) fn to_arrow_compatible_df(df: &DataFrame) -> DataFrame {
[INFO] [stdout]   |               ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `resolve_homedir`
[INFO] [stdout]   --> src/utils.rs:18:8
[INFO] [stdout]    |
[INFO] [stdout] 18 | pub fn resolve_homedir(path: &Path) -> PathBuf {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `finish`
[INFO] [stdout]    --> src/lib.rs:178:19
[INFO] [stdout]     |
[INFO] [stdout] 178 |     pub(crate) fn finish(&self, df: &DataFrame) -> Result<Series> {
[INFO] [stdout]     |                   ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `polars-core`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustc --crate-name polars_core --edition=2018 /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/polars-core-0.15.1/src/lib.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts --crate-type lib --emit=dep-info,metadata,link -C embed-bitcode=no -C debuginfo=2 --cfg 'feature="private"' -C metadata=f943d83030804faf -C extra-filename=-f943d83030804faf --out-dir /opt/rustwide/target/debug/deps -L dependency=/opt/rustwide/target/debug/deps --extern ahash=/opt/rustwide/target/debug/deps/libahash-908cbf8b6eabde98.rmeta --extern anyhow=/opt/rustwide/target/debug/deps/libanyhow-a6de331f7eb7ef5b.rmeta --extern arrow=/opt/rustwide/target/debug/deps/libarrow-03417d03797c1d47.rmeta --extern hashbrown=/opt/rustwide/target/debug/deps/libhashbrown-4908f392379e5a88.rmeta --extern itertools=/opt/rustwide/target/debug/deps/libitertools-c0ea5b4b1d6f2c02.rmeta --extern lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-df981c5871754530.rmeta --extern num=/opt/rustwide/target/debug/deps/libnum-1f27d7e81dd40434.rmeta --extern num_cpus=/opt/rustwide/target/debug/deps/libnum_cpus-6aa8c0f7f41c04d4.rmeta --extern polars_arrow=/opt/rustwide/target/debug/deps/libpolars_arrow-6f6daf805b9bce70.rmeta --extern rayon=/opt/rustwide/target/debug/deps/librayon-3420e84d71a91800.rmeta --extern thiserror=/opt/rustwide/target/debug/deps/libthiserror-17a713c032b59283.rmeta --extern unsafe_unwrap=/opt/rustwide/target/debug/deps/libunsafe_unwrap-d1fec151c6d3142a.rmeta --cap-lints allow --cap-lints=warn` (signal: 9, SIGKILL: kill)
[INFO] running `Command { std: "docker" "inspect" "cadea2dc870c497c95903c01fe29669938a732ba29250f8c637e2004935cad11", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cadea2dc870c497c95903c01fe29669938a732ba29250f8c637e2004935cad11", kill_on_drop: false }`
[INFO] [stdout] cadea2dc870c497c95903c01fe29669938a732ba29250f8c637e2004935cad11