[INFO] fetching crate mgrrs 0.1.0...
[INFO] checking mgrrs-0.1.0 against beta for pr-78714
[INFO] extracting crate mgrrs 0.1.0 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate mgrrs 0.1.0 on toolchain beta
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mgrrs 0.1.0
[INFO] finished tweaking crates.io crate mgrrs 0.1.0
[INFO] tweaked toml for crates.io crate mgrrs 0.1.0 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate crates.io crate mgrrs 0.1.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 64bcb3cc6b2c1db42afe1953197ca74b691a0ac9cf3cb1e31010c086f4e905b8
[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" "64bcb3cc6b2c1db42afe1953197ca74b691a0ac9cf3cb1e31010c086f4e905b8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "64bcb3cc6b2c1db42afe1953197ca74b691a0ac9cf3cb1e31010c086f4e905b8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "64bcb3cc6b2c1db42afe1953197ca74b691a0ac9cf3cb1e31010c086f4e905b8", kill_on_drop: false }`
[INFO] [stdout] 64bcb3cc6b2c1db42afe1953197ca74b691a0ac9cf3cb1e31010c086f4e905b8
[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" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "check" "--frozen" "--all" "--all-targets" "--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] 1239eae364cb740a5a125ffc48fe115e2c22235b8876534277fdde2971c848fb
[INFO] running `Command { std: "docker" "start" "-a" "1239eae364cb740a5a125ffc48fe115e2c22235b8876534277fdde2971c848fb", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling syn v1.0.8
[INFO] [stderr]    Compiling escargot v0.3.1
[INFO] [stderr]     Checking normalize-line-endings v0.2.2
[INFO] [stderr]    Compiling backtrace-sys v0.1.32
[INFO] [stderr]     Checking float-cmp v0.4.0
[INFO] [stderr]     Checking tempfile v3.1.0
[INFO] [stderr]     Checking console v0.9.1
[INFO] [stderr]     Checking structopt v0.2.18
[INFO] [stderr]     Checking predicates v1.0.1
[INFO] [stderr]     Checking indicatif v0.13.0
[INFO] [stderr]     Checking backtrace v0.3.40
[INFO] [stderr]    Compiling synstructure v0.12.2
[INFO] [stderr]    Compiling failure_derive v0.1.6
[INFO] [stderr]    Compiling serde_derive v1.0.102
[INFO] [stderr]     Checking failure v0.1.6
[INFO] [stderr]     Checking exitfailure v0.5.1
[INFO] [stderr]     Checking mgrrs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]  --> src/lib.rs:4:13
[INFO] [stdout]   |
[INFO] [stdout] 4 |             writeln!(writer, "{}", line);
[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 a macro (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]     Checking serde v1.0.102
[INFO] [stderr]     Checking serde_json v1.0.41
[INFO] [stderr]     Checking assert_cmd v0.10.2
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]  --> src/lib.rs:4:13
[INFO] [stdout]   |
[INFO] [stdout] 4 |             writeln!(writer, "{}", line);
[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 a macro (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 import: `self`
[INFO] [stdout]  --> tests/cli.rs:5:15
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::io::{self, Write};
[INFO] [stdout]   |               ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> tests/cli.rs:9:45
[INFO] [stdout]   |
[INFO] [stdout] 9 | fn find_content_in_file() -> Result<(), Box<std::error::Error>> {
[INFO] [stdout]   |                                             ^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn std::error::Error`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> tests/cli.rs:23:42
[INFO] [stdout]    |
[INFO] [stdout] 23 | fn file_doesnt_exist() -> Result<(), Box<std::error::Error>> {
[INFO] [stdout]    |                                          ^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn std::error::Error`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 35.94s
[INFO] running `Command { std: "docker" "inspect" "1239eae364cb740a5a125ffc48fe115e2c22235b8876534277fdde2971c848fb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1239eae364cb740a5a125ffc48fe115e2c22235b8876534277fdde2971c848fb", kill_on_drop: false }`
[INFO] [stdout] 1239eae364cb740a5a125ffc48fe115e2c22235b8876534277fdde2971c848fb