[INFO] updating cached repository https://github.com/zhaihj/rust-play-ground
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/big/crater/work/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 7518e53f966e8c30644755ca289ee59c1d0e0a21
[INFO] checking zhaihj/rust-play-ground against master#4ff32c07da9d97e6dc315a4a5c9ffbb797cb27bb for pr-64672
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzhaihj%2Frust-play-ground" "work/builds/worker-4/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/zhaihj/rust-play-ground on toolchain 4ff32c07da9d97e6dc315a4a5c9ffbb797cb27bb
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+4ff32c07da9d97e6dc315a4a5c9ffbb797cb27bb" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/zhaihj/rust-play-ground
[INFO] finished tweaking git repo https://github.com/zhaihj/rust-play-ground
[INFO] tweaked toml for git repo https://github.com/zhaihj/rust-play-ground written to work/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/zhaihj/rust-play-ground already has a lockfile, it will not be regenerated
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+4ff32c07da9d97e6dc315a4a5c9ffbb797cb27bb" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+4ff32c07da9d97e6dc315a4a5c9ffbb797cb27bb" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] d6240f17aa95699aa1fec10a190991cf9917d534c2c00f4b32991792b821c2eb
[INFO] running `"docker" "start" "-a" "d6240f17aa95699aa1fec10a190991cf9917d534c2c00f4b32991792b821c2eb"`
[INFO] [stderr]     Checking libc v0.2.19
[INFO] [stderr]     Checking memchr v1.0.1
[INFO] [stderr]     Checking csv v0.15.0
[INFO] [stderr]     Checking csv-read-test v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]  --> src/bin/read-csv-matrix.rs:8:5
[INFO] [stderr]   |
[INFO] [stderr] 8 |     f.read_to_string(&mut s);
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]   = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]  --> src/bin/read-csv-matrix.rs:8:5
[INFO] [stderr]   |
[INFO] [stderr] 8 |     f.read_to_string(&mut s);
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]   = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 2.95s
[INFO] running `"docker" "inspect" "d6240f17aa95699aa1fec10a190991cf9917d534c2c00f4b32991792b821c2eb"`
[INFO] running `"docker" "rm" "-f" "d6240f17aa95699aa1fec10a190991cf9917d534c2c00f4b32991792b821c2eb"`
[INFO] [stdout] d6240f17aa95699aa1fec10a190991cf9917d534c2c00f4b32991792b821c2eb