[INFO] updating cached repository https://github.com/myself659/avltree
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/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] 2408a6a6eadad2c48086268f33aba7039affcde8
[INFO] checking myself659/avltree against master#bd0bacc694d7d8175804bb6f690cb846bfa4a9ee for pr-71665
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmyself659%2Favltree" "/workspace/builds/worker-11/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-11/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/myself659/avltree on toolchain bd0bacc694d7d8175804bb6f690cb846bfa4a9ee
[INFO] running `"/workspace/cargo-home/bin/cargo" "+bd0bacc694d7d8175804bb6f690cb846bfa4a9ee" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/myself659/avltree
[INFO] finished tweaking git repo https://github.com/myself659/avltree
[INFO] tweaked toml for git repo https://github.com/myself659/avltree written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] crate git repo https://github.com/myself659/avltree already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+bd0bacc694d7d8175804bb6f690cb846bfa4a9ee" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "MAP_USER_ID=0" "-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" "+bd0bacc694d7d8175804bb6f690cb846bfa4a9ee" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 35f4181e685066db4ad649f3a6cbc97d2250594fa6c1729eacd8dec47f3cbad9
[INFO] running `"docker" "start" "-a" "35f4181e685066db4ad649f3a6cbc97d2250594fa6c1729eacd8dec47f3cbad9"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]     Checking rand_core v0.4.2
[INFO] [stderr]    Compiling autocfg v0.1.5
[INFO] [stderr]    Compiling memchr v2.2.1
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]     Checking lazy_static v1.3.0
[INFO] [stderr]     Checking regex-syntax v0.6.11
[INFO] [stderr]     Checking cfg-if v0.1.9
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking either v1.5.2
[INFO] [stderr]     Checking avltree v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking thread_local v0.3.6
[INFO] [stderr]     Checking itertools v0.8.0
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/set.rs:118:17
[INFO] [stderr]     |
[INFO] [stderr] 118 |                 replace(&mut target_node.right, right_node.right.take());
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/set.rs:139:17
[INFO] [stderr]     |
[INFO] [stderr] 139 |                 replace(&mut parent_left_node.left, leftmost_node.right.take());
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr] warning: 2 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Checking rand_jitter v0.1.4
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]     Checking rand_hc v0.1.0
[INFO] [stderr]     Checking rand_isaac v0.1.1
[INFO] [stderr]     Checking rand_xorshift v0.1.1
[INFO] [stderr]     Checking aho-corasick v0.7.6
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]     Checking regex v1.2.1
[INFO] [stderr]     Checking env_logger v0.6.2
[INFO] [stderr]     Checking quickcheck v0.8.5
[INFO] [stderr]    Compiling quickcheck_macros v0.8.0
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/set.rs:118:17
[INFO] [stderr]     |
[INFO] [stderr] 118 |                 replace(&mut target_node.right, right_node.right.take());
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/set.rs:139:17
[INFO] [stderr]     |
[INFO] [stderr] 139 |                 replace(&mut parent_left_node.left, leftmost_node.right.take());
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: 2 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 37.46s
[INFO] running `"docker" "inspect" "35f4181e685066db4ad649f3a6cbc97d2250594fa6c1729eacd8dec47f3cbad9"`
[INFO] running `"docker" "rm" "-f" "35f4181e685066db4ad649f3a6cbc97d2250594fa6c1729eacd8dec47f3cbad9"`
[INFO] [stdout] 35f4181e685066db4ad649f3a6cbc97d2250594fa6c1729eacd8dec47f3cbad9