[INFO] fetching crate shelldraw 0.1.0...
[INFO] checking shelldraw-0.1.0 against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] extracting crate shelldraw 0.1.0 into /workspace/builds/worker-3-tc2/source
[INFO] started tweaking crates.io crate shelldraw 0.1.0
[INFO] finished tweaking crates.io crate shelldraw 0.1.0
[INFO] tweaked toml for crates.io crate shelldraw 0.1.0 written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate shelldraw 0.1.0 on toolchain 4f260f0f20b3133d20cfb50353c0221943af5796
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate shelldraw 0.1.0 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" "+4f260f0f20b3133d20cfb50353c0221943af5796" "fetch" "--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-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e71661c42341a1aeca84dcc094ebf489144fa99b5649879f7c41e6a4b7cd7397
[INFO] running `Command { std: "docker" "start" "-a" "e71661c42341a1aeca84dcc094ebf489144fa99b5649879f7c41e6a4b7cd7397", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e71661c42341a1aeca84dcc094ebf489144fa99b5649879f7c41e6a4b7cd7397", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e71661c42341a1aeca84dcc094ebf489144fa99b5649879f7c41e6a4b7cd7397", kill_on_drop: false }`
[INFO] [stdout] e71661c42341a1aeca84dcc094ebf489144fa99b5649879f7c41e6a4b7cd7397
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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 -Dunmustuse_in_always_ok" "-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] cf2fca1b5c930263aedc839908e1cf36350f39fb9aa05652e68169b48acdaf28
[INFO] running `Command { std: "docker" "start" "-a" "cf2fca1b5c930263aedc839908e1cf36350f39fb9aa05652e68169b48acdaf28", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.78
[INFO] [stderr]    Compiling serde_json v1.0.114
[INFO] [stderr]     Checking itoa v1.0.10
[INFO] [stderr]    Compiling quote v1.0.35
[INFO] [stderr]    Compiling syn v2.0.50
[INFO] [stderr]    Compiling serde_derive v1.0.197
[INFO] [stderr]     Checking serde v1.0.197
[INFO] [stderr]     Checking shelldraw v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `File`
[INFO] [stdout]  --> src/main.rs:4:21
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::fs::{self, File};
[INFO] [stdout]   |                     ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Read` and `Write`
[INFO] [stdout]  --> src/main.rs:5:21
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::io::{self, Read, Write};
[INFO] [stdout]   |                     ^^^^  ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `File`
[INFO] [stdout]  --> src/main.rs:4:21
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::fs::{self, File};
[INFO] [stdout]   |                     ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Read` and `Write`
[INFO] [stdout]  --> src/main.rs:5:21
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::io::{self, Read, Write};
[INFO] [stdout]   |                     ^^^^  ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> src/main.rs:142:9
[INFO] [stdout]     |
[INFO] [stdout] 142 |     for y in 0..height {
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]    --> src/main.rs:144:13
[INFO] [stdout]     |
[INFO] [stdout] 144 |         for x in 0..width {
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<std::string::String, Infallible>
[INFO] [stdout]    --> src/main.rs:101:32
[INFO] [stdout]     |
[INFO] [stdout] 101 |                     let text = args[4].parse::<String>().unwrap();
[INFO] [stdout]     |                                ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<std::string::String, Infallible>
[INFO] [stdout]    --> src/main.rs:117:32
[INFO] [stdout]     |
[INFO] [stdout] 117 |                     let text = args[4].parse::<String>().unwrap();
[INFO] [stdout]     |                                ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `shelldraw` (bin "shelldraw" test) due to 2 previous errors; 4 warnings emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> src/main.rs:142:9
[INFO] [stdout]     |
[INFO] [stdout] 142 |     for y in 0..height {
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]    --> src/main.rs:144:13
[INFO] [stdout]     |
[INFO] [stdout] 144 |         for x in 0..width {
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<std::string::String, Infallible>
[INFO] [stdout]    --> src/main.rs:101:32
[INFO] [stdout]     |
[INFO] [stdout] 101 |                     let text = args[4].parse::<String>().unwrap();
[INFO] [stdout]     |                                ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<std::string::String, Infallible>
[INFO] [stdout]    --> src/main.rs:117:32
[INFO] [stdout]     |
[INFO] [stdout] 117 |                     let text = args[4].parse::<String>().unwrap();
[INFO] [stdout]     |                                ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `shelldraw` (bin "shelldraw") due to 2 previous errors; 4 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "cf2fca1b5c930263aedc839908e1cf36350f39fb9aa05652e68169b48acdaf28", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cf2fca1b5c930263aedc839908e1cf36350f39fb9aa05652e68169b48acdaf28", kill_on_drop: false }`
[INFO] [stdout] cf2fca1b5c930263aedc839908e1cf36350f39fb9aa05652e68169b48acdaf28