[INFO] cloning repository https://github.com/Etc3tera/RustFSExample
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Etc3tera/RustFSExample" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FEtc3tera%2FRustFSExample", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FEtc3tera%2FRustFSExample'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 819834b85797802f3788cd6a24028f7d8ca252a0
[INFO] testing Etc3tera/RustFSExample against master#8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e for pr-74409
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FEtc3tera%2FRustFSExample" "/workspace/builds/worker-5/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Etc3tera/RustFSExample on toolchain 8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Etc3tera/RustFSExample
[INFO] finished tweaking git repo https://github.com/Etc3tera/RustFSExample
[INFO] tweaked toml for git repo https://github.com/Etc3tera/RustFSExample written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] crate git repo https://github.com/Etc3tera/RustFSExample already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:38e1b949b06cde1964af550a6e548bd9b2b2ea170003ae122f8fc0886596cc07" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "metadata" "--no-deps" "--format-version=1", 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] 35d583c397d2445178b7135dc288b43b4415ae80bc72ded611f65760c55c7131
[INFO] running `Command { std: "docker" "start" "-a" "35d583c397d2445178b7135dc288b43b4415ae80bc72ded611f65760c55c7131", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "35d583c397d2445178b7135dc288b43b4415ae80bc72ded611f65760c55c7131", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "35d583c397d2445178b7135dc288b43b4415ae80bc72ded611f65760c55c7131", kill_on_drop: false }`
[INFO] [stdout] 35d583c397d2445178b7135dc288b43b4415ae80bc72ded611f65760c55c7131
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:38e1b949b06cde1964af550a6e548bd9b2b2ea170003ae122f8fc0886596cc07" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e1fda3c98ce8d4c12b2adb3f540740a3c880457a604d50582a4f992da1da14ee
[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" "e1fda3c98ce8d4c12b2adb3f540740a3c880457a604d50582a4f992da1da14ee", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.3
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]    Compiling serde v1.0.100
[INFO] [stderr]    Compiling ryu v1.0.0
[INFO] [stderr]    Compiling autocfg v0.1.6
[INFO] [stderr]    Compiling bincode v1.1.4
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]    Compiling serde_derive v1.0.100
[INFO] [stderr]    Compiling serde_json v1.0.40
[INFO] [stderr]    Compiling rust_fs_io v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 15 |     stdin.lock().read_line(&mut 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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:16:5
[INFO] [stdout]    |
[INFO] [stdout] 16 |     fp.write_all(b"1");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 |     stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:18:5
[INFO] [stdout]    |
[INFO] [stdout] 18 |     fp.write_all(b"2");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:19:5
[INFO] [stdout]    |
[INFO] [stdout] 19 |     stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:20:5
[INFO] [stdout]    |
[INFO] [stdout] 20 |     fp.write_all(b"3");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:21:5
[INFO] [stdout]    |
[INFO] [stdout] 21 |     stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:22:5
[INFO] [stdout]    |
[INFO] [stdout] 22 |     fp.seek(SeekFrom::Start(0));
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 23 |     fp.write_all(b"4");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:24:5
[INFO] [stdout]    |
[INFO] [stdout] 24 |     stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:25:5
[INFO] [stdout]    |
[INFO] [stdout] 25 |     fp.write_all(b"5");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:26:5
[INFO] [stdout]    |
[INFO] [stdout] 26 |     stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::io::SeekFrom`
[INFO] [stdout]  --> src/serialize_binary.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::io::SeekFrom;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `serde_json::Result`
[INFO] [stdout]  --> src/serialize_text.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use serde_json::Result;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/serialize_binary.rs:47:9
[INFO] [stdout]    |
[INFO] [stdout] 47 |         fp.write_all(&bin);
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/serialize_text.rs:44:9
[INFO] [stdout]    |
[INFO] [stdout] 44 |         fp.write_all(json.as_bytes());
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/serialize_text.rs:53:5
[INFO] [stdout]    |
[INFO] [stdout] 53 |     fp.read_to_string(&mut buffer);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 12 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 37.46s
[INFO] running `Command { std: "docker" "inspect" "e1fda3c98ce8d4c12b2adb3f540740a3c880457a604d50582a4f992da1da14ee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e1fda3c98ce8d4c12b2adb3f540740a3c880457a604d50582a4f992da1da14ee", kill_on_drop: false }`
[INFO] [stdout] e1fda3c98ce8d4c12b2adb3f540740a3c880457a604d50582a4f992da1da14ee
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:38e1b949b06cde1964af550a6e548bd9b2b2ea170003ae122f8fc0886596cc07" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0ee83f67ed316bf1089f00a4a6ae59f12f3d5660a2d302ce956b836188c8641e
[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" "0ee83f67ed316bf1089f00a4a6ae59f12f3d5660a2d302ce956b836188c8641e", kill_on_drop: false }`
[INFO] [stderr]    Compiling rust_fs_io v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::io::SeekFrom`
[INFO] [stdout]  --> src/serialize_binary.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::io::SeekFrom;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 15 |     stdin.lock().read_line(&mut 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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:16:5
[INFO] [stdout]    |
[INFO] [stdout] 16 |     fp.write_all(b"1");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 |     stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:18:5
[INFO] [stdout]    |
[INFO] [stdout] 18 |     fp.write_all(b"2");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:19:5
[INFO] [stdout]    |
[INFO] [stdout] 19 |     stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:20:5
[INFO] [stdout]    |
[INFO] [stdout] 20 |     fp.write_all(b"3");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:21:5
[INFO] [stdout]    |
[INFO] [stdout] 21 |     stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:22:5
[INFO] [stdout]    |
[INFO] [stdout] 22 |     fp.seek(SeekFrom::Start(0));
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 23 |     fp.write_all(b"4");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:24:5
[INFO] [stdout]    |
[INFO] [stdout] 24 |     stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:25:5
[INFO] [stdout]    |
[INFO] [stdout] 25 |     fp.write_all(b"5");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/example.rs:26:5
[INFO] [stdout]    |
[INFO] [stdout] 26 |     stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `serde_json::Result`
[INFO] [stdout]  --> src/serialize_text.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use serde_json::Result;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/serialize_binary.rs:47:9
[INFO] [stdout]    |
[INFO] [stdout] 47 |         fp.write_all(&bin);
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/serialize_text.rs:44:9
[INFO] [stdout]    |
[INFO] [stdout] 44 |         fp.write_all(json.as_bytes());
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/serialize_text.rs:53:5
[INFO] [stdout]    |
[INFO] [stdout] 53 |     fp.read_to_string(&mut buffer);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 12 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.87s
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "0ee83f67ed316bf1089f00a4a6ae59f12f3d5660a2d302ce956b836188c8641e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0ee83f67ed316bf1089f00a4a6ae59f12f3d5660a2d302ce956b836188c8641e", kill_on_drop: false }`
[INFO] [stdout] 0ee83f67ed316bf1089f00a4a6ae59f12f3d5660a2d302ce956b836188c8641e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:38e1b949b06cde1964af550a6e548bd9b2b2ea170003ae122f8fc0886596cc07" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] b0db16e651c4ce89ce445bdc79435ea1eead35ce37827dc3435ed52f07c3c250
[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" "b0db16e651c4ce89ce445bdc79435ea1eead35ce37827dc3435ed52f07c3c250", kill_on_drop: false }`
[INFO] [stderr] warning: unused import: `std::io::SeekFrom`
[INFO] [stderr]  --> src/serialize_binary.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use std::io::SeekFrom;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/serialize_binary.rs:47:9
[INFO] [stderr]    |
[INFO] [stderr] 47 |         fp.write_all(&bin);
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: 2 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `serde_json::Result`
[INFO] [stderr]  --> src/serialize_text.rs:2:5
[INFO] [stderr]   |
[INFO] [stderr] 2 | use serde_json::Result;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/serialize_text.rs:44:9
[INFO] [stderr]    |
[INFO] [stderr] 44 |         fp.write_all(json.as_bytes());
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/serialize_text.rs:53:5
[INFO] [stderr]    |
[INFO] [stderr] 53 |     fp.read_to_string(&mut buffer);
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: 3 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/example.rs:15:5
[INFO] [stderr]    |
[INFO] [stderr] 15 |     stdin.lock().read_line(&mut line);
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/example.rs:16:5
[INFO] [stderr]    |
[INFO] [stderr] 16 |     fp.write_all(b"1");
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/example.rs:17:5
[INFO] [stderr]    |
[INFO] [stderr] 17 |     stdin.lock().read_line(&mut line);
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/example.rs:18:5
[INFO] [stderr]    |
[INFO] [stderr] 18 |     fp.write_all(b"2");
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/example.rs:19:5
[INFO] [stderr]    |
[INFO] [stderr] 19 |     stdin.lock().read_line(&mut line);
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/example.rs:20:5
[INFO] [stderr]    |
[INFO] [stderr] 20 |     fp.write_all(b"3");
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/example.rs:21:5
[INFO] [stderr]    |
[INFO] [stderr] 21 |     stdin.lock().read_line(&mut line);
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/example.rs:22:5
[INFO] [stderr]    |
[INFO] [stderr] 22 |     fp.seek(SeekFrom::Start(0));
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/example.rs:23:5
[INFO] [stderr]    |
[INFO] [stderr] 23 |     fp.write_all(b"4");
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/example.rs:24:5
[INFO] [stderr]    |
[INFO] [stderr] 24 |     stdin.lock().read_line(&mut line);
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/example.rs:25:5
[INFO] [stderr]    |
[INFO] [stderr] 25 |     fp.write_all(b"5");
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/example.rs:26:5
[INFO] [stderr]    |
[INFO] [stderr] 26 |     stdin.lock().read_line(&mut line);
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: 12 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.11s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/example-3fe8df7b8c7155b4
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/serialize_binary-6ee1e9bdd8e9e891
[INFO] [stdout] 
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/serialize_text-87ff5e4d7d9d4a11
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "b0db16e651c4ce89ce445bdc79435ea1eead35ce37827dc3435ed52f07c3c250", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b0db16e651c4ce89ce445bdc79435ea1eead35ce37827dc3435ed52f07c3c250", kill_on_drop: false }`
[INFO] [stdout] b0db16e651c4ce89ce445bdc79435ea1eead35ce37827dc3435ed52f07c3c250