[INFO] cloning repository https://github.com/scottgifford/nerdlebot
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/scottgifford/nerdlebot" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscottgifford%2Fnerdlebot", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscottgifford%2Fnerdlebot'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 0024b0d1fbed1b388d4ce0adac14a2eafd7a0c8b
[INFO] checking scottgifford/nerdlebot against master#385fa9d845dd326c6bbfd58c22244215e431948a for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscottgifford%2Fnerdlebot" "/workspace/builds/worker-7-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/scottgifford/nerdlebot on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/scottgifford/nerdlebot
[INFO] finished tweaking git repo https://github.com/scottgifford/nerdlebot
[INFO] tweaked toml for git repo https://github.com/scottgifford/nerdlebot written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/scottgifford/nerdlebot already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded crossbeam-epoch v0.9.8
[INFO] [stderr]   Downloaded crossbeam-utils v0.8.8
[INFO] [stderr]   Downloaded semver v1.0.7
[INFO] [stderr]   Downloaded crossbeam-channel v0.5.4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7b6a19ffa039122e9617a3e0d57266481d221cff1ca4338d90aaa9c5e77e0f21
[INFO] running `Command { std: "docker" "start" "-a" "7b6a19ffa039122e9617a3e0d57266481d221cff1ca4338d90aaa9c5e77e0f21", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7b6a19ffa039122e9617a3e0d57266481d221cff1ca4338d90aaa9c5e77e0f21", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7b6a19ffa039122e9617a3e0d57266481d221cff1ca4338d90aaa9c5e77e0f21", kill_on_drop: false }`
[INFO] [stdout] 7b6a19ffa039122e9617a3e0d57266481d221cff1ca4338d90aaa9c5e77e0f21
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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" "RUSTDOCFLAGS=--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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7f4567fd3ada8070079640158f7f8a1a75aa26d5dbf2e572f79c1c27215cdc83
[INFO] running `Command { std: "docker" "start" "-a" "7f4567fd3ada8070079640158f7f8a1a75aa26d5dbf2e572f79c1c27215cdc83", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.103
[INFO] [stderr]    Compiling crossbeam-utils v0.8.8
[INFO] [stderr]    Compiling semver v1.0.7
[INFO] [stderr]    Compiling serde v1.0.136
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.8
[INFO] [stderr]    Compiling proc-macro2 v1.0.37
[INFO] [stderr]    Compiling rayon-core v1.9.1
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling syn v1.0.91
[INFO] [stderr]    Compiling rayon v1.5.1
[INFO] [stderr]     Checking plotters-backend v0.3.2
[INFO] [stderr]     Checking unicode-width v0.1.9
[INFO] [stderr]     Checking regex-automata v0.1.10
[INFO] [stderr]     Checking csv-core v0.1.10
[INFO] [stderr]     Checking itertools v0.10.3
[INFO] [stderr]     Checking oorandom v11.1.3
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]     Checking plotters-svg v0.3.1
[INFO] [stderr]     Checking clap v2.34.0
[INFO] [stderr]     Checking crossbeam-channel v0.5.4
[INFO] [stderr]    Compiling rustc_version v0.4.0
[INFO] [stderr]     Checking crossbeam-deque v0.8.1
[INFO] [stderr]     Checking plotters v0.3.1
[INFO] [stderr]    Compiling quote v1.0.17
[INFO] [stderr]    Compiling cast v0.2.7
[INFO] [stderr]     Checking getrandom v0.2.3
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking num_cpus v1.13.1
[INFO] [stderr]     Checking colored v2.0.0
[INFO] [stderr]     Checking rand_core v0.6.3
[INFO] [stderr]     Checking criterion-plot v0.4.4
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking rand v0.8.4
[INFO] [stderr]     Checking nerdlebot v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/nerdledata.rs:132:17
[INFO] [stdout]     |
[INFO] [stdout] 132 |             let mut ent = self.char_info.entry(*ch).or_insert(NerdleCharInfo::new());
[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: variable does not need to be mutable
[INFO] [stdout]    --> src/nerdledata.rs:145:21
[INFO] [stdout]     |
[INFO] [stdout] 145 |                 let mut char_info = self.char_info.entry(*ch).or_insert(NerdleCharInfo::new());
[INFO] [stdout]     |                     ----^^^^^^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking serde_json v1.0.79
[INFO] [stderr]     Checking bstr v0.2.17
[INFO] [stderr]     Checking serde_cbor v0.11.2
[INFO] [stderr]     Checking csv v1.1.6
[INFO] [stderr]     Checking tinytemplate v1.2.1
[INFO] [stderr]    Compiling serde_derive v1.0.136
[INFO] [stderr]     Checking criterion v0.3.5
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/nerdledata.rs:132:17
[INFO] [stdout]     |
[INFO] [stdout] 132 |             let mut ent = self.char_info.entry(*ch).or_insert(NerdleCharInfo::new());
[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: variable does not need to be mutable
[INFO] [stdout]    --> src/nerdledata.rs:145:21
[INFO] [stdout]     |
[INFO] [stdout] 145 |                 let mut char_info = self.char_info.entry(*ch).or_insert(NerdleCharInfo::new());
[INFO] [stdout]     |                     ----^^^^^^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 20.32s
[INFO] [stderr] warning: the following packages contain code that will be rejected by a future version of Rust: criterion v0.3.5
[INFO] [stderr] note: to see what the problems were, use the option `--future-incompat-report`, or run `cargo report future-incompatibilities --id 4`
[INFO] running `Command { std: "docker" "inspect" "7f4567fd3ada8070079640158f7f8a1a75aa26d5dbf2e572f79c1c27215cdc83", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7f4567fd3ada8070079640158f7f8a1a75aa26d5dbf2e572f79c1c27215cdc83", kill_on_drop: false }`
[INFO] [stdout] 7f4567fd3ada8070079640158f7f8a1a75aa26d5dbf2e572f79c1c27215cdc83
[INFO] checking scottgifford/nerdlebot against try#2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2 for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscottgifford%2Fnerdlebot" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/scottgifford/nerdlebot on toolchain 2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/scottgifford/nerdlebot
[INFO] finished tweaking git repo https://github.com/scottgifford/nerdlebot
[INFO] tweaked toml for git repo https://github.com/scottgifford/nerdlebot written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/scottgifford/nerdlebot already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d2c120375decdc0cf3fb373e21cc3e4eae7e93e8f18e016f38ea58c22b47dc9f
[INFO] running `Command { std: "docker" "start" "-a" "d2c120375decdc0cf3fb373e21cc3e4eae7e93e8f18e016f38ea58c22b47dc9f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d2c120375decdc0cf3fb373e21cc3e4eae7e93e8f18e016f38ea58c22b47dc9f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d2c120375decdc0cf3fb373e21cc3e4eae7e93e8f18e016f38ea58c22b47dc9f", kill_on_drop: false }`
[INFO] [stdout] d2c120375decdc0cf3fb373e21cc3e4eae7e93e8f18e016f38ea58c22b47dc9f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/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" "RUSTDOCFLAGS=--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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e0b15e613ec43eaa792771ccb047b536f74d98f6d3dc5c688b887ca956070e21
[INFO] running `Command { std: "docker" "start" "-a" "e0b15e613ec43eaa792771ccb047b536f74d98f6d3dc5c688b887ca956070e21", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.103
[INFO] [stderr]    Compiling semver v1.0.7
[INFO] [stderr]    Compiling crossbeam-utils v0.8.8
[INFO] [stderr]    Compiling serde v1.0.136
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.8
[INFO] [stderr]    Compiling proc-macro2 v1.0.37
[INFO] [stderr]    Compiling rayon-core v1.9.1
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling syn v1.0.91
[INFO] [stderr]    Compiling rayon v1.5.1
[INFO] [stderr]     Checking unicode-width v0.1.9
[INFO] [stderr]     Checking plotters-backend v0.3.2
[INFO] [stderr]     Checking regex-automata v0.1.10
[INFO] [stderr]     Checking csv-core v0.1.10
[INFO] [stderr]     Checking itertools v0.10.3
[INFO] [stderr]     Checking oorandom v11.1.3
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]     Checking clap v2.34.0
[INFO] [stderr]     Checking plotters-svg v0.3.1
[INFO] [stderr]     Checking crossbeam-channel v0.5.4
[INFO] [stderr]     Checking crossbeam-deque v0.8.1
[INFO] [stderr]    Compiling rustc_version v0.4.0
[INFO] [stderr]    Compiling cast v0.2.7
[INFO] [stderr]     Checking plotters v0.3.1
[INFO] [stderr]    Compiling quote v1.0.17
[INFO] [stderr]     Checking getrandom v0.2.3
[INFO] [stderr]     Checking num_cpus v1.13.1
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking colored v2.0.0
[INFO] [stderr]     Checking rand_core v0.6.3
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking criterion-plot v0.4.4
[INFO] [stderr]     Checking rand v0.8.4
[INFO] [stderr]     Checking nerdlebot v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/nerdledata.rs:132:17
[INFO] [stdout]     |
[INFO] [stdout] 132 |             let mut ent = self.char_info.entry(*ch).or_insert(NerdleCharInfo::new());
[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: variable does not need to be mutable
[INFO] [stdout]    --> src/nerdledata.rs:145:21
[INFO] [stdout]     |
[INFO] [stdout] 145 |                 let mut char_info = self.char_info.entry(*ch).or_insert(NerdleCharInfo::new());
[INFO] [stdout]     |                     ----^^^^^^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking bstr v0.2.17
[INFO] [stderr]     Checking serde_json v1.0.79
[INFO] [stderr]     Checking serde_cbor v0.11.2
[INFO] [stderr]     Checking csv v1.1.6
[INFO] [stderr]     Checking tinytemplate v1.2.1
[INFO] [stderr]    Compiling serde_derive v1.0.136
[INFO] [stderr]     Checking criterion v0.3.5
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/nerdledata.rs:132:17
[INFO] [stdout]     |
[INFO] [stdout] 132 |             let mut ent = self.char_info.entry(*ch).or_insert(NerdleCharInfo::new());
[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: variable does not need to be mutable
[INFO] [stdout]    --> src/nerdledata.rs:145:21
[INFO] [stdout]     |
[INFO] [stdout] 145 |                 let mut char_info = self.char_info.entry(*ch).or_insert(NerdleCharInfo::new());
[INFO] [stdout]     |                     ----^^^^^^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 13.63s
[INFO] [stderr] warning: the following packages contain code that will be rejected by a future version of Rust: criterion v0.3.5
[INFO] [stderr] note: to see what the problems were, use the option `--future-incompat-report`, or run `cargo report future-incompatibilities --id 4`
[INFO] running `Command { std: "docker" "inspect" "e0b15e613ec43eaa792771ccb047b536f74d98f6d3dc5c688b887ca956070e21", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e0b15e613ec43eaa792771ccb047b536f74d98f6d3dc5c688b887ca956070e21", kill_on_drop: false }`
[INFO] [stdout] e0b15e613ec43eaa792771ccb047b536f74d98f6d3dc5c688b887ca956070e21