[INFO] cloning repository https://github.com/remychantenay/rust-microgrep
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/remychantenay/rust-microgrep" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fremychantenay%2Frust-microgrep", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fremychantenay%2Frust-microgrep'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 85abd52e7bb7023ef68c154747948495bf024fc3
[INFO] checking remychantenay/rust-microgrep against master#dfd7b8d03fb93d0e03147d28b3be6d93260fa94d for pr-87050
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fremychantenay%2Frust-microgrep" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/remychantenay/rust-microgrep on toolchain dfd7b8d03fb93d0e03147d28b3be6d93260fa94d
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/remychantenay/rust-microgrep
[INFO] finished tweaking git repo https://github.com/remychantenay/rust-microgrep
[INFO] tweaked toml for git repo https://github.com/remychantenay/rust-microgrep written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/remychantenay/rust-microgrep already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 01c5761f5826a4db7547153c3baa3f27b2fc68c9c348788b8a85d17095195bcb
[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" "01c5761f5826a4db7547153c3baa3f27b2fc68c9c348788b8a85d17095195bcb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "01c5761f5826a4db7547153c3baa3f27b2fc68c9c348788b8a85d17095195bcb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "01c5761f5826a4db7547153c3baa3f27b2fc68c9c348788b8a85d17095195bcb", kill_on_drop: false }`
[INFO] [stdout] 01c5761f5826a4db7547153c3baa3f27b2fc68c9c348788b8a85d17095195bcb
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 518478e2c9404c3682d7a44c9d7a5df7b7cc08d535d32e16c02b5bbaf2be8afb
[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" "518478e2c9404c3682d7a44c9d7a5df7b7cc08d535d32e16c02b5bbaf2be8afb", kill_on_drop: false }`
[INFO] [stderr]     Checking microgrep v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/io/mod.rs:5:61
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub fn file_to_string(filename: &str) -> Result<String, Box<Error>> {
[INFO] [stdout]   |                                                             ^^^^^ help: use `dyn`: `dyn Error`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout]   = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]   = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:40:46
[INFO] [stdout]    |
[INFO] [stdout] 40 | pub fn run(config: Config) -> Result<(), Box<Error>> {
[INFO] [stdout]    |                                              ^^^^^ help: use `dyn`: `dyn Error`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/lib.rs:44:9
[INFO] [stdout]    |
[INFO] [stdout] 44 |     let mut search_results: Vec<&str>;
[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: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/io/mod.rs:5:61
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub fn file_to_string(filename: &str) -> Result<String, Box<Error>> {
[INFO] [stdout]   |                                                             ^^^^^ help: use `dyn`: `dyn Error`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout]   = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]   = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:40:46
[INFO] [stdout]    |
[INFO] [stdout] 40 | pub fn run(config: Config) -> Result<(), Box<Error>> {
[INFO] [stdout]    |                                              ^^^^^ help: use `dyn`: `dyn Error`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/lib.rs:44:9
[INFO] [stdout]    |
[INFO] [stdout] 44 |     let mut search_results: Vec<&str>;
[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: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.01s
[INFO] running `Command { std: "docker" "inspect" "518478e2c9404c3682d7a44c9d7a5df7b7cc08d535d32e16c02b5bbaf2be8afb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "518478e2c9404c3682d7a44c9d7a5df7b7cc08d535d32e16c02b5bbaf2be8afb", kill_on_drop: false }`
[INFO] [stdout] 518478e2c9404c3682d7a44c9d7a5df7b7cc08d535d32e16c02b5bbaf2be8afb