[INFO] cloning repository https://github.com/Snektron/mamba
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Snektron/mamba" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSnektron%2Fmamba", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSnektron%2Fmamba'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 8e16034b3ed9bcf9a5a92b15d9ce65d3bcf8360e
[INFO] testing Snektron/mamba against beta-2021-01-01 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSnektron%2Fmamba" "/workspace/builds/worker-7/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Snektron/mamba on toolchain beta-2021-01-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Snektron/mamba
[INFO] finished tweaking git repo https://github.com/Snektron/mamba
[INFO] tweaked toml for git repo https://github.com/Snektron/mamba written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded diff v0.1.12
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3c96cf8cd222441d5cca8e6cb9a16b335da662bda4d594a4065e7373f8cd3043
[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" "3c96cf8cd222441d5cca8e6cb9a16b335da662bda4d594a4065e7373f8cd3043", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3c96cf8cd222441d5cca8e6cb9a16b335da662bda4d594a4065e7373f8cd3043", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3c96cf8cd222441d5cca8e6cb9a16b335da662bda4d594a4065e7373f8cd3043", kill_on_drop: false }`
[INFO] [stdout] 3c96cf8cd222441d5cca8e6cb9a16b335da662bda4d594a4065e7373f8cd3043
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "build" "--frozen" "--message-format=json", 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] 25ecfe9b3d7b98f567d8610a53ee3d43b57643234453c1abfaa0e9e203efc12f
[INFO] running `Command { std: "docker" "start" "-a" "25ecfe9b3d7b98f567d8610a53ee3d43b57643234453c1abfaa0e9e203efc12f", kill_on_drop: false }`
[INFO] [stderr]    Compiling siphasher v0.2.3
[INFO] [stderr]    Compiling syn v1.0.58
[INFO] [stderr]    Compiling serde_derive v1.0.118
[INFO] [stderr]    Compiling serde v1.0.118
[INFO] [stderr]    Compiling string_cache_shared v0.3.0
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]    Compiling byte-tools v0.3.1
[INFO] [stderr]    Compiling new_debug_unreachable v1.0.4
[INFO] [stderr]    Compiling fixedbitset v0.1.9
[INFO] [stderr]    Compiling opaque-debug v0.2.3
[INFO] [stderr]    Compiling precomputed-hash v0.1.1
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]    Compiling ordermap v0.3.5
[INFO] [stderr]    Compiling term v0.4.6
[INFO] [stderr]    Compiling lalrpop-util v0.16.3
[INFO] [stderr]    Compiling diff v0.1.12
[INFO] [stderr]    Compiling block-padding v0.1.5
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling generic-array v0.12.3
[INFO] [stderr]    Compiling ena v0.11.0
[INFO] [stderr]    Compiling itertools v0.8.2
[INFO] [stderr]    Compiling phf_shared v0.7.24
[INFO] [stderr]    Compiling regex v1.4.2
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling petgraph v0.4.13
[INFO] [stderr]    Compiling ascii-canvas v1.0.0
[INFO] [stderr]    Compiling digest v0.8.1
[INFO] [stderr]    Compiling block-buffer v0.7.3
[INFO] [stderr]    Compiling sha2 v0.8.2
[INFO] [stderr]    Compiling phf_generator v0.7.24
[INFO] [stderr]    Compiling string_cache_codegen v0.4.4
[INFO] [stderr]    Compiling string_cache v0.7.5
[INFO] [stderr]    Compiling docopt v1.1.0
[INFO] [stderr]    Compiling lalrpop v0.16.3
[INFO] [stderr]    Compiling mamba v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:1861:5
[INFO] [stdout]      |
[INFO] [stdout] 1861 |     (__0)
[INFO] [stdout]      |     ^^^^^ help: remove these parentheses
[INFO] [stdout]      |
[INFO] [stdout]      = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:1934:5
[INFO] [stdout]      |
[INFO] [stdout] 1934 |     (__0)
[INFO] [stdout]      |     ^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:1947:5
[INFO] [stdout]      |
[INFO] [stdout] 1947 |     (__0)
[INFO] [stdout]      |     ^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:1995:5
[INFO] [stdout]      |
[INFO] [stdout] 1995 |     (__0)
[INFO] [stdout]      |     ^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:2009:5
[INFO] [stdout]      |
[INFO] [stdout] 2009 |     (__0)
[INFO] [stdout]      |     ^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:2216:5
[INFO] [stdout]      |
[INFO] [stdout] 2216 |     (__0)
[INFO] [stdout]      |     ^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/ast/construct.rs:188:13
[INFO] [stdout]     |
[INFO] [stdout] 188 |         let mut t = check_arms(&from, arms, &states, &alphabet)?;
[INFO] [stdout]     |             ----^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1m 50s
[INFO] running `Command { std: "docker" "inspect" "25ecfe9b3d7b98f567d8610a53ee3d43b57643234453c1abfaa0e9e203efc12f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "25ecfe9b3d7b98f567d8610a53ee3d43b57643234453c1abfaa0e9e203efc12f", kill_on_drop: false }`
[INFO] [stdout] 25ecfe9b3d7b98f567d8610a53ee3d43b57643234453c1abfaa0e9e203efc12f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c069cf60ca70baa83d3ddfd0e793723651713ec27f0d7a7e73b40eb54c45ec03
[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" "c069cf60ca70baa83d3ddfd0e793723651713ec27f0d7a7e73b40eb54c45ec03", kill_on_drop: false }`
[INFO] [stderr]    Compiling mamba v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:1861:5
[INFO] [stdout]      |
[INFO] [stdout] 1861 |     (__0)
[INFO] [stdout]      |     ^^^^^ help: remove these parentheses
[INFO] [stdout]      |
[INFO] [stdout]      = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:1934:5
[INFO] [stdout]      |
[INFO] [stdout] 1934 |     (__0)
[INFO] [stdout]      |     ^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:1947:5
[INFO] [stdout]      |
[INFO] [stdout] 1947 |     (__0)
[INFO] [stdout]      |     ^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:1995:5
[INFO] [stdout]      |
[INFO] [stdout] 1995 |     (__0)
[INFO] [stdout]      |     ^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:2009:5
[INFO] [stdout]      |
[INFO] [stdout] 2009 |     (__0)
[INFO] [stdout]      |     ^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:2216:5
[INFO] [stdout]      |
[INFO] [stdout] 2216 |     (__0)
[INFO] [stdout]      |     ^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/ast/construct.rs:188:13
[INFO] [stdout]     |
[INFO] [stdout] 188 |         let mut t = check_arms(&from, arms, &states, &alphabet)?;
[INFO] [stdout]     |             ----^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 1.79s
[INFO] running `Command { std: "docker" "inspect" "c069cf60ca70baa83d3ddfd0e793723651713ec27f0d7a7e73b40eb54c45ec03", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c069cf60ca70baa83d3ddfd0e793723651713ec27f0d7a7e73b40eb54c45ec03", kill_on_drop: false }`
[INFO] [stdout] c069cf60ca70baa83d3ddfd0e793723651713ec27f0d7a7e73b40eb54c45ec03
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] cc0ce8596a99d64242a8f26ab5738859d28917337aad8cc939164b91cc33a3f7
[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" "cc0ce8596a99d64242a8f26ab5738859d28917337aad8cc939164b91cc33a3f7", kill_on_drop: false }`
[INFO] [stderr] warning: unnecessary parentheses around block return value
[INFO] [stderr]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:1861:5
[INFO] [stderr]      |
[INFO] [stderr] 1861 |     (__0)
[INFO] [stderr]      |     ^^^^^ help: remove these parentheses
[INFO] [stderr]      |
[INFO] [stderr]      = note: `#[warn(unused_parens)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around block return value
[INFO] [stderr]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:1934:5
[INFO] [stderr]      |
[INFO] [stderr] 1934 |     (__0)
[INFO] [stderr]      |     ^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around block return value
[INFO] [stderr]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:1947:5
[INFO] [stderr]      |
[INFO] [stderr] 1947 |     (__0)
[INFO] [stderr]      |     ^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around block return value
[INFO] [stderr]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:1995:5
[INFO] [stderr]      |
[INFO] [stderr] 1995 |     (__0)
[INFO] [stderr]      |     ^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around block return value
[INFO] [stderr]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:2009:5
[INFO] [stderr]      |
[INFO] [stderr] 2009 |     (__0)
[INFO] [stderr]      |     ^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around block return value
[INFO] [stderr]     --> /opt/rustwide/target/debug/build/mamba-2b63c528356ba49c/out/parser/grammar.rs:2216:5
[INFO] [stderr]      |
[INFO] [stderr] 2216 |     (__0)
[INFO] [stderr]      |     ^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/ast/construct.rs:188:13
[INFO] [stderr]     |
[INFO] [stderr] 188 |         let mut t = check_arms(&from, arms, &states, &alphabet)?;
[INFO] [stderr]     |             ----^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: 7 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.09s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/mamba-0021f2a8cbd68c31
[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" "cc0ce8596a99d64242a8f26ab5738859d28917337aad8cc939164b91cc33a3f7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cc0ce8596a99d64242a8f26ab5738859d28917337aad8cc939164b91cc33a3f7", kill_on_drop: false }`
[INFO] [stdout] cc0ce8596a99d64242a8f26ab5738859d28917337aad8cc939164b91cc33a3f7