[INFO] fetching crate mmapio 0.9.1...
[INFO] checking mmapio-0.9.1 against master#ab869e094a907cc5d19b4080f22eccaf347f1f95 for pr-129604
[INFO] extracting crate mmapio 0.9.1 into /workspace/builds/worker-7-tc1/source
[INFO] validating manifest of crates.io crate mmapio 0.9.1 on toolchain ab869e094a907cc5d19b4080f22eccaf347f1f95
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mmapio 0.9.1
[INFO] finished tweaking crates.io crate mmapio 0.9.1
[INFO] tweaked toml for crates.io crate mmapio 0.9.1 written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate crates.io crate mmapio 0.9.1 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" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0cb044901740e11bb95c2e474fe95e3feac0a2cd3d338b104093115dd0c40a35
[INFO] running `Command { std: "docker" "start" "-a" "0cb044901740e11bb95c2e474fe95e3feac0a2cd3d338b104093115dd0c40a35", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0cb044901740e11bb95c2e474fe95e3feac0a2cd3d338b104093115dd0c40a35", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0cb044901740e11bb95c2e474fe95e3feac0a2cd3d338b104093115dd0c40a35", kill_on_drop: false }`
[INFO] [stdout] 0cb044901740e11bb95c2e474fe95e3feac0a2cd3d338b104093115dd0c40a35
[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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f55788b34b75080b476272cec4129dbf9a9be13dcca3de2fa48fcd19cd47b064
[INFO] running `Command { std: "docker" "start" "-a" "f55788b34b75080b476272cec4129dbf9a9be13dcca3de2fa48fcd19cd47b064", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.86
[INFO] [stderr]     Checking remove_dir_all v0.5.3
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]     Checking mmapio v0.9.1 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking tempdir v0.3.7
[INFO] [stdout] warning: unused variable: `path`
[INFO] [stdout]     --> src/lib.rs:1199:13
[INFO] [stdout]      |
[INFO] [stdout] 1199 |         let path = tempdir.path().join("mmap");
[INFO] [stdout]      |             ^^^^ help: if this is intentional, prefix it with an underscore: `_path`
[INFO] [stdout]      |
[INFO] [stdout]      = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]     --> src/lib.rs:1202:13
[INFO] [stdout]      |
[INFO] [stdout] 1202 |         let mut file = OpenOptions::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/lib.rs:1223:17
[INFO] [stdout]      |
[INFO] [stdout] 1223 |             let mut file = OpenOptions::new()
[INFO] [stdout]      |                 ----^^^^
[INFO] [stdout]      |                 |
[INFO] [stdout]      |                 help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/lib.rs:866:9
[INFO] [stdout]     |
[INFO] [stdout] 866 |         file.set_len(0);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 866 |         let _ = file.set_len(0);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]     --> src/lib.rs:1042:13
[INFO] [stdout]      |
[INFO] [stdout] 1042 |             &mmap[..];
[INFO] [stdout]      |             ^^^^^^^^^ the borrow produces a value
[INFO] [stdout]      |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]      |
[INFO] [stdout] 1042 |             let _ = &mmap[..];
[INFO] [stdout]      |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.37s
[INFO] running `Command { std: "docker" "inspect" "f55788b34b75080b476272cec4129dbf9a9be13dcca3de2fa48fcd19cd47b064", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f55788b34b75080b476272cec4129dbf9a9be13dcca3de2fa48fcd19cd47b064", kill_on_drop: false }`
[INFO] [stdout] f55788b34b75080b476272cec4129dbf9a9be13dcca3de2fa48fcd19cd47b064