[INFO] cloning repository https://github.com/kpfromer/rust-ipv4-dns-resolver
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/kpfromer/rust-ipv4-dns-resolver" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkpfromer%2Frust-ipv4-dns-resolver", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkpfromer%2Frust-ipv4-dns-resolver'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 34660caee66fc5406516f9b19ac6f89eb96fb15c
[INFO] checking kpfromer/rust-ipv4-dns-resolver against master#5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f for pr-87248
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkpfromer%2Frust-ipv4-dns-resolver" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/kpfromer/rust-ipv4-dns-resolver on toolchain 5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/kpfromer/rust-ipv4-dns-resolver
[INFO] finished tweaking git repo https://github.com/kpfromer/rust-ipv4-dns-resolver
[INFO] tweaked toml for git repo https://github.com/kpfromer/rust-ipv4-dns-resolver written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/kpfromer/rust-ipv4-dns-resolver already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded dns-lookup v1.0.6
[INFO] [stderr]   Downloaded num-traits v0.2.14
[INFO] [stderr]   Downloaded autocfg v1.0.1
[INFO] [stderr]   Downloaded num-integer v0.1.44
[INFO] [stderr]   Downloaded anyhow v1.0.40
[INFO] [stderr]   Downloaded time v0.1.44
[INFO] [stderr]   Downloaded chrono v0.4.19
[INFO] [stderr]   Downloaded syn v1.0.67
[INFO] [stderr]   Downloaded socket2 v0.4.0
[INFO] [stderr]   Downloaded libc v0.2.92
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8350dec3c1febdacfdf8ee442a1a2253a5ad2f6e7bb621778f23a83843172ad7
[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" "8350dec3c1febdacfdf8ee442a1a2253a5ad2f6e7bb621778f23a83843172ad7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8350dec3c1febdacfdf8ee442a1a2253a5ad2f6e7bb621778f23a83843172ad7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8350dec3c1febdacfdf8ee442a1a2253a5ad2f6e7bb621778f23a83843172ad7", kill_on_drop: false }`
[INFO] [stdout] 8350dec3c1febdacfdf8ee442a1a2253a5ad2f6e7bb621778f23a83843172ad7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7c8bf44f6e9725525b4127b51bd4e3dffa38c271c66f31794ffce3165bfc26a7
[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" "7c8bf44f6e9725525b4127b51bd4e3dffa38c271c66f31794ffce3165bfc26a7", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.92
[INFO] [stderr]    Compiling version_check v0.9.3
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling syn v1.0.67
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]     Checking unicode-width v0.1.8
[INFO] [stderr]    Compiling unicode-segmentation v1.7.1
[INFO] [stderr]     Checking vec_map v0.8.2
[INFO] [stderr]    Compiling anyhow v1.0.40
[INFO] [stderr]     Checking strsim v0.8.0
[INFO] [stderr]     Checking ansi_term v0.11.0
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling heck v0.3.2
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking socket2 v0.4.0
[INFO] [stderr]     Checking time v0.1.44
[INFO] [stderr]     Checking clap v2.33.3
[INFO] [stderr]     Checking dns-lookup v1.0.6
[INFO] [stderr]     Checking chrono v0.4.19
[INFO] [stderr]    Compiling structopt-derive v0.4.14
[INFO] [stderr]     Checking structopt v0.3.21
[INFO] [stderr]     Checking ipv4-resolver v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:96:17
[INFO] [stdout]    |
[INFO] [stdout] 96 |                 threadprintln!("thread {} serviced {} files", thread_id + 1, serviced_files);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in the macro `writeln` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:110:17
[INFO] [stdout]     |
[INFO] [stdout] 110 |                 threadprintln!("thread {} resolved {} hostnames", thread_id + 1, resolved);
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: this warning originates in the macro `writeln` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/consumer.rs:45:17
[INFO] [stdout]    |
[INFO] [stdout] 45 |                 threadprintln!("Error looking up Address: Name or service not known");
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in the macro `writeln` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:96:17
[INFO] [stdout]    |
[INFO] [stdout] 96 |                 threadprintln!("thread {} serviced {} files", thread_id + 1, serviced_files);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in the macro `writeln` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:110:17
[INFO] [stdout]     |
[INFO] [stdout] 110 |                 threadprintln!("thread {} resolved {} hostnames", thread_id + 1, resolved);
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: this warning originates in the macro `writeln` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/consumer.rs:45:17
[INFO] [stdout]    |
[INFO] [stdout] 45 |                 threadprintln!("Error looking up Address: Name or service not known");
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in the macro `writeln` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 21.24s
[INFO] running `Command { std: "docker" "inspect" "7c8bf44f6e9725525b4127b51bd4e3dffa38c271c66f31794ffce3165bfc26a7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7c8bf44f6e9725525b4127b51bd4e3dffa38c271c66f31794ffce3165bfc26a7", kill_on_drop: false }`
[INFO] [stdout] 7c8bf44f6e9725525b4127b51bd4e3dffa38c271c66f31794ffce3165bfc26a7