[INFO] fetching crate think_cap 0.0.1...
[INFO] testing think_cap-0.0.1 against master#432e145bd5a974c5b6f4dd9b352891bd7502b69d for pr-87041
[INFO] extracting crate think_cap 0.0.1 into /workspace/builds/worker-15/source
[INFO] validating manifest of crates.io crate think_cap 0.0.1 on toolchain 432e145bd5a974c5b6f4dd9b352891bd7502b69d
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate think_cap 0.0.1
[INFO] finished tweaking crates.io crate think_cap 0.0.1
[INFO] tweaked toml for crates.io crate think_cap 0.0.1 written to /workspace/builds/worker-15/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/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" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 9971a4168bb4aaa25c8d1498c32f17a3177328b8dcc41a7aa4160d1dafd4cf19
[INFO] running `Command { std: "docker" "start" "-a" "9971a4168bb4aaa25c8d1498c32f17a3177328b8dcc41a7aa4160d1dafd4cf19", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9971a4168bb4aaa25c8d1498c32f17a3177328b8dcc41a7aa4160d1dafd4cf19", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9971a4168bb4aaa25c8d1498c32f17a3177328b8dcc41a7aa4160d1dafd4cf19", kill_on_drop: false }`
[INFO] [stdout] 9971a4168bb4aaa25c8d1498c32f17a3177328b8dcc41a7aa4160d1dafd4cf19
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/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" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f5c03a22b4725ec0a1ed711d05fa11474f9250bb2edbe6009a8dc2c628c8f8cd
[INFO] running `Command { std: "docker" "start" "-a" "f5c03a22b4725ec0a1ed711d05fa11474f9250bb2edbe6009a8dc2c628c8f8cd", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.98
[INFO] [stderr]    Compiling rustc-serialize v0.3.24
[INFO] [stderr]    Compiling rand v0.4.6
[INFO] [stderr]    Compiling time v0.1.44
[INFO] [stderr]    Compiling rand v0.3.23
[INFO] [stderr]    Compiling think_cap v0.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: use of deprecated macro `RustcDecodable`: rustc-serialize is deprecated and no longer supported
[INFO] [stdout]    --> src/lib.rs:187:24
[INFO] [stdout]     |
[INFO] [stdout] 187 | #[derive(Debug, Clone, RustcDecodable, RustcEncodable)]
[INFO] [stdout]     |                        ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `RustcEncodable`: rustc-serialize is deprecated and no longer supported
[INFO] [stdout]    --> src/lib.rs:187:40
[INFO] [stdout]     |
[INFO] [stdout] 187 | #[derive(Debug, Clone, RustcDecodable, RustcEncodable)]
[INFO] [stdout]     |                                        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:361:17
[INFO] [stdout]     |
[INFO] [stdout] 361 |             let mut layer = &mut self.layers[layer_index];
[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/lib.rs:364:21
[INFO] [stdout]     |
[INFO] [stdout] 364 |                 let mut node = &mut layer[node_index];
[INFO] [stdout]     |                     ----^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:394:21
[INFO] [stdout]     |
[INFO] [stdout] 394 |                 let mut node_error;
[INFO] [stdout]     |                     ----^^^^^^^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:410:25
[INFO] [stdout]     |
[INFO] [stdout] 410 |                     let mut prev_layer_result;
[INFO] [stdout]     |                         ----^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |                         |
[INFO] [stdout]     |                         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 4.27s
[INFO] running `Command { std: "docker" "inspect" "f5c03a22b4725ec0a1ed711d05fa11474f9250bb2edbe6009a8dc2c628c8f8cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f5c03a22b4725ec0a1ed711d05fa11474f9250bb2edbe6009a8dc2c628c8f8cd", kill_on_drop: false }`
[INFO] [stdout] f5c03a22b4725ec0a1ed711d05fa11474f9250bb2edbe6009a8dc2c628c8f8cd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/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" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c1a59fcd7caa5dc14d5c5d8e75498b32005ea8e3745811e0827907cfdc41e291
[INFO] running `Command { std: "docker" "start" "-a" "c1a59fcd7caa5dc14d5c5d8e75498b32005ea8e3745811e0827907cfdc41e291", kill_on_drop: false }`
[INFO] [stderr]    Compiling think_cap v0.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: use of deprecated macro `RustcDecodable`: rustc-serialize is deprecated and no longer supported
[INFO] [stdout]    --> src/lib.rs:187:24
[INFO] [stdout]     |
[INFO] [stdout] 187 | #[derive(Debug, Clone, RustcDecodable, RustcEncodable)]
[INFO] [stdout]     |                        ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `RustcEncodable`: rustc-serialize is deprecated and no longer supported
[INFO] [stdout]    --> src/lib.rs:187:40
[INFO] [stdout]     |
[INFO] [stdout] 187 | #[derive(Debug, Clone, RustcDecodable, RustcEncodable)]
[INFO] [stdout]     |                                        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:361:17
[INFO] [stdout]     |
[INFO] [stdout] 361 |             let mut layer = &mut self.layers[layer_index];
[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/lib.rs:364:21
[INFO] [stdout]     |
[INFO] [stdout] 364 |                 let mut node = &mut layer[node_index];
[INFO] [stdout]     |                     ----^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:394:21
[INFO] [stdout]     |
[INFO] [stdout] 394 |                 let mut node_error;
[INFO] [stdout]     |                     ----^^^^^^^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:410:25
[INFO] [stdout]     |
[INFO] [stdout] 410 |                     let mut prev_layer_result;
[INFO] [stdout]     |                         ----^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |                         |
[INFO] [stdout]     |                         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `RustcDecodable`: rustc-serialize is deprecated and no longer supported
[INFO] [stdout]    --> src/lib.rs:187:24
[INFO] [stdout]     |
[INFO] [stdout] 187 | #[derive(Debug, Clone, RustcDecodable, RustcEncodable)]
[INFO] [stdout]     |                        ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `RustcEncodable`: rustc-serialize is deprecated and no longer supported
[INFO] [stdout]    --> src/lib.rs:187:40
[INFO] [stdout]     |
[INFO] [stdout] 187 | #[derive(Debug, Clone, RustcDecodable, RustcEncodable)]
[INFO] [stdout]     |                                        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:361:17
[INFO] [stdout]     |
[INFO] [stdout] 361 |             let mut layer = &mut self.layers[layer_index];
[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/lib.rs:364:21
[INFO] [stdout]     |
[INFO] [stdout] 364 |                 let mut node = &mut layer[node_index];
[INFO] [stdout]     |                     ----^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:394:21
[INFO] [stdout]     |
[INFO] [stdout] 394 |                 let mut node_error;
[INFO] [stdout]     |                     ----^^^^^^^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:410:25
[INFO] [stdout]     |
[INFO] [stdout] 410 |                     let mut prev_layer_result;
[INFO] [stdout]     |                         ----^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |                         |
[INFO] [stdout]     |                         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.98s
[INFO] running `Command { std: "docker" "inspect" "c1a59fcd7caa5dc14d5c5d8e75498b32005ea8e3745811e0827907cfdc41e291", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c1a59fcd7caa5dc14d5c5d8e75498b32005ea8e3745811e0827907cfdc41e291", kill_on_drop: false }`
[INFO] [stdout] c1a59fcd7caa5dc14d5c5d8e75498b32005ea8e3745811e0827907cfdc41e291
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/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" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 2f91b1a5e06732de82aac5119cc8f590e62a28999d0fbd71df97e6d02f582f9f
[INFO] running `Command { std: "docker" "start" "-a" "2f91b1a5e06732de82aac5119cc8f590e62a28999d0fbd71df97e6d02f582f9f", kill_on_drop: false }`
[INFO] [stderr] warning: use of deprecated macro `RustcDecodable`: rustc-serialize is deprecated and no longer supported
[INFO] [stderr]    --> src/lib.rs:187:24
[INFO] [stderr]     |
[INFO] [stderr] 187 | #[derive(Debug, Clone, RustcDecodable, RustcEncodable)]
[INFO] [stderr]     |                        ^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(deprecated)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated macro `RustcEncodable`: rustc-serialize is deprecated and no longer supported
[INFO] [stderr]    --> src/lib.rs:187:40
[INFO] [stderr]     |
[INFO] [stderr] 187 | #[derive(Debug, Clone, RustcDecodable, RustcEncodable)]
[INFO] [stderr]     |                                        ^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:361:17
[INFO] [stderr]     |
[INFO] [stderr] 361 |             let mut layer = &mut self.layers[layer_index];
[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: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:364:21
[INFO] [stderr]     |
[INFO] [stderr] 364 |                 let mut node = &mut layer[node_index];
[INFO] [stderr]     |                     ----^^^^
[INFO] [stderr]     |                     |
[INFO] [stderr]     |                     help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:394:21
[INFO] [stderr]     |
[INFO] [stderr] 394 |                 let mut node_error;
[INFO] [stderr]     |                     ----^^^^^^^^^^
[INFO] [stderr]     |                     |
[INFO] [stderr]     |                     help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:410:25
[INFO] [stderr]     |
[INFO] [stderr] 410 |                     let mut prev_layer_result;
[INFO] [stderr]     |                         ----^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |                         |
[INFO] [stderr]     |                         help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: 6 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated macro `RustcDecodable`: rustc-serialize is deprecated and no longer supported
[INFO] [stderr]    --> src/lib.rs:187:24
[INFO] [stderr]     |
[INFO] [stderr] 187 | #[derive(Debug, Clone, RustcDecodable, RustcEncodable)]
[INFO] [stderr]     |                        ^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(deprecated)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated macro `RustcEncodable`: rustc-serialize is deprecated and no longer supported
[INFO] [stderr]    --> src/lib.rs:187:40
[INFO] [stderr]     |
[INFO] [stderr] 187 | #[derive(Debug, Clone, RustcDecodable, RustcEncodable)]
[INFO] [stderr]     |                                        ^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:361:17
[INFO] [stderr]     |
[INFO] [stderr] 361 |             let mut layer = &mut self.layers[layer_index];
[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: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:364:21
[INFO] [stderr]     |
[INFO] [stderr] 364 |                 let mut node = &mut layer[node_index];
[INFO] [stderr]     |                     ----^^^^
[INFO] [stderr]     |                     |
[INFO] [stderr]     |                     help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:394:21
[INFO] [stderr]     |
[INFO] [stderr] 394 |                 let mut node_error;
[INFO] [stderr]     |                     ----^^^^^^^^^^
[INFO] [stderr]     |                     |
[INFO] [stderr]     |                     help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:410:25
[INFO] [stderr]     |
[INFO] [stderr] 410 |                     let mut prev_layer_result;
[INFO] [stderr]     |                         ----^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |                         |
[INFO] [stderr]     |                         help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: 6 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/think_cap-6f9073dbbac7b3c7)
[INFO] [stdout] 
[INFO] [stderr]      Running tests/match.rs (/opt/rustwide/target/debug/deps/match-87ad10d3b9913f98)
[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 1 test
[INFO] [stdout] test match_4_layers ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 2.69s
[INFO] [stdout] 
[INFO] [stderr]      Running tests/xor.rs (/opt/rustwide/target/debug/deps/xor-2d3f81339f14e5a6)
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test xor_4layers ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 3.07s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests think_cap
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test src/lib.rs - (line 21) ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 1.39s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "2f91b1a5e06732de82aac5119cc8f590e62a28999d0fbd71df97e6d02f582f9f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2f91b1a5e06732de82aac5119cc8f590e62a28999d0fbd71df97e6d02f582f9f", kill_on_drop: false }`
[INFO] [stdout] 2f91b1a5e06732de82aac5119cc8f590e62a28999d0fbd71df97e6d02f582f9f