[INFO] cloning repository https://github.com/lucaspoffo/markov_chain
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/lucaspoffo/markov_chain" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flucaspoffo%2Fmarkov_chain", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flucaspoffo%2Fmarkov_chain'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] d67657284eacd67f24653a0209b22304c163396b
[INFO] testing lucaspoffo/markov_chain against master#62efba8a050c64249dab942951bb28f710208bc8 for pr-90799
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flucaspoffo%2Fmarkov_chain" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/lucaspoffo/markov_chain on toolchain 62efba8a050c64249dab942951bb28f710208bc8
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+62efba8a050c64249dab942951bb28f710208bc8" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/lucaspoffo/markov_chain
[INFO] finished tweaking git repo https://github.com/lucaspoffo/markov_chain
[INFO] tweaked toml for git repo https://github.com/lucaspoffo/markov_chain written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/lucaspoffo/markov_chain already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+62efba8a050c64249dab942951bb28f710208bc8" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+62efba8a050c64249dab942951bb28f710208bc8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] cfc78ccdfbeb4b10ea9400e41c7af8545666a9a4aa95c46b6d2d8bdfd7c56702
[INFO] running `Command { std: "docker" "start" "-a" "cfc78ccdfbeb4b10ea9400e41c7af8545666a9a4aa95c46b6d2d8bdfd7c56702", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cfc78ccdfbeb4b10ea9400e41c7af8545666a9a4aa95c46b6d2d8bdfd7c56702", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cfc78ccdfbeb4b10ea9400e41c7af8545666a9a4aa95c46b6d2d8bdfd7c56702", kill_on_drop: false }`
[INFO] [stdout] cfc78ccdfbeb4b10ea9400e41c7af8545666a9a4aa95c46b6d2d8bdfd7c56702
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+62efba8a050c64249dab942951bb28f710208bc8" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 569229e026dbb941d538d20170cf683fb10788938fa1311c094bc8b7087158cc
[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" "569229e026dbb941d538d20170cf683fb10788938fa1311c094bc8b7087158cc", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.66
[INFO] [stderr]    Compiling getrandom v0.1.14
[INFO] [stderr]    Compiling ppv-lite86 v0.2.6
[INFO] [stderr]    Compiling c2-chacha v0.2.3
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling rand_chacha v0.2.1
[INFO] [stderr]    Compiling rand v0.7.2
[INFO] [stderr]    Compiling markov_chain v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/lib.rs:133:7
[INFO] [stdout]     |
[INFO] [stdout] 133 |       write!(f, "\t{:?}:\n", key);
[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 `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 10.08s
[INFO] running `Command { std: "docker" "inspect" "569229e026dbb941d538d20170cf683fb10788938fa1311c094bc8b7087158cc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "569229e026dbb941d538d20170cf683fb10788938fa1311c094bc8b7087158cc", kill_on_drop: false }`
[INFO] [stdout] 569229e026dbb941d538d20170cf683fb10788938fa1311c094bc8b7087158cc
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+62efba8a050c64249dab942951bb28f710208bc8" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1b472cc33bb1835aefea9d8e240dcc4d1ce16a0add02099809d0d3eeccbdab58
[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" "1b472cc33bb1835aefea9d8e240dcc4d1ce16a0add02099809d0d3eeccbdab58", kill_on_drop: false }`
[INFO] [stderr]    Compiling markov_chain v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/lib.rs:133:7
[INFO] [stdout]     |
[INFO] [stdout] 133 |       write!(f, "\t{:?}:\n", key);
[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 `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/lib.rs:133:7
[INFO] [stdout]     |
[INFO] [stdout] 133 |       write!(f, "\t{:?}:\n", key);
[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 `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 2.11s
[INFO] running `Command { std: "docker" "inspect" "1b472cc33bb1835aefea9d8e240dcc4d1ce16a0add02099809d0d3eeccbdab58", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1b472cc33bb1835aefea9d8e240dcc4d1ce16a0add02099809d0d3eeccbdab58", kill_on_drop: false }`
[INFO] [stdout] 1b472cc33bb1835aefea9d8e240dcc4d1ce16a0add02099809d0d3eeccbdab58
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+62efba8a050c64249dab942951bb28f710208bc8" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 843ae0c4adeaeb2b4ee653a56429c04410d6de97dd07da9284d95a4187dba0da
[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" "843ae0c4adeaeb2b4ee653a56429c04410d6de97dd07da9284d95a4187dba0da", kill_on_drop: false }`
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]    --> src/lib.rs:133:7
[INFO] [stderr]     |
[INFO] [stderr] 133 |       write!(f, "\t{:?}:\n", key);
[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]     = note: this warning originates in the macro `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stdout] 
[INFO] [stderr] warning: `markov_chain` (lib) generated 1 warning
[INFO] [stdout] running 2 tests
[INFO] [stderr] warning: `markov_chain` (lib test) generated 1 warning (1 duplicate)
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.03s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/markov_chain-f808542eba8c51ab)
[INFO] [stdout] test tests::feed ... ok
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/markov_chain-512427829201b297)
[INFO] [stdout] test tests::generate ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 2 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.01s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests markov_chain
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "843ae0c4adeaeb2b4ee653a56429c04410d6de97dd07da9284d95a4187dba0da", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "843ae0c4adeaeb2b4ee653a56429c04410d6de97dd07da9284d95a4187dba0da", kill_on_drop: false }`
[INFO] [stdout] 843ae0c4adeaeb2b4ee653a56429c04410d6de97dd07da9284d95a4187dba0da