[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 try#722e1797249a965b6335aebd65d777f917e498f1 for pr-91031
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FEtc3tera%2FRustFSExample" "/workspace/builds/worker-37/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-37/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Etc3tera/RustFSExample on toolchain 722e1797249a965b6335aebd65d777f917e498f1
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+722e1797249a965b6335aebd65d777f917e498f1" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", 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-37/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" "+722e1797249a965b6335aebd65d777f917e498f1" "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-37/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-37/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+722e1797249a965b6335aebd65d777f917e498f1" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] fb9d90a33310c033bc9250954ce4a7cc7ef8f9d075342596077b53f4df29db23
[INFO] running `Command { std: "docker" "start" "-a" "fb9d90a33310c033bc9250954ce4a7cc7ef8f9d075342596077b53f4df29db23", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "fb9d90a33310c033bc9250954ce4a7cc7ef8f9d075342596077b53f4df29db23", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fb9d90a33310c033bc9250954ce4a7cc7ef8f9d075342596077b53f4df29db23", kill_on_drop: false }`
[INFO] [stdout] fb9d90a33310c033bc9250954ce4a7cc7ef8f9d075342596077b53f4df29db23
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-37/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-37/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+722e1797249a965b6335aebd65d777f917e498f1" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d50d165d0976f8006e4ee983283e4c77d97501c4583a12125cf541bad8f087ad
[INFO] running `Command { std: "docker" "start" "-a" "d50d165d0976f8006e4ee983283e4c77d97501c4583a12125cf541bad8f087ad", 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 byteorder v1.3.2
[INFO] [stderr]    Compiling autocfg v0.1.6
[INFO] [stderr]    Compiling ryu v1.0.0
[INFO] [stderr]    Compiling itoa v0.4.4
[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 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 `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 `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 `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 `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 `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 `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 `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 `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 `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 `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 `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 `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 `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 `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 `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] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1m 40s
[INFO] running `Command { std: "docker" "inspect" "d50d165d0976f8006e4ee983283e4c77d97501c4583a12125cf541bad8f087ad", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d50d165d0976f8006e4ee983283e4c77d97501c4583a12125cf541bad8f087ad", kill_on_drop: false }`
[INFO] [stdout] d50d165d0976f8006e4ee983283e4c77d97501c4583a12125cf541bad8f087ad
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-37/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-37/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+722e1797249a965b6335aebd65d777f917e498f1" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 37f41903a4f2bb48506da9f8e32c58e8ae873c05c1e3b4f9bdeee73593188845
[INFO] running `Command { std: "docker" "start" "-a" "37f41903a4f2bb48506da9f8e32c58e8ae873c05c1e3b4f9bdeee73593188845", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling rust_fs_io v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `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 `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 `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 `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 `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 `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 `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 `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 `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 `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 `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 `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 `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 `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 `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] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.81s
[INFO] running `Command { std: "docker" "inspect" "37f41903a4f2bb48506da9f8e32c58e8ae873c05c1e3b4f9bdeee73593188845", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "37f41903a4f2bb48506da9f8e32c58e8ae873c05c1e3b4f9bdeee73593188845", kill_on_drop: false }`
[INFO] [stdout] 37f41903a4f2bb48506da9f8e32c58e8ae873c05c1e3b4f9bdeee73593188845
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-37/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-37/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+722e1797249a965b6335aebd65d777f917e498f1" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 12cc7b8060919d77cdf3ff820e678992acd0d294ffaa82f5600eb7c51f46bf11
[INFO] running `Command { std: "docker" "start" "-a" "12cc7b8060919d77cdf3ff820e678992acd0d294ffaa82f5600eb7c51f46bf11", 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 `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: unused `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 `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 `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 `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 `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 `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 `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 `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 `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 `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 `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 `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: 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 `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 `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: `rust_fs_io` (bin "serialize_binary" test) generated 2 warnings
[INFO] [stderr] warning: `rust_fs_io` (bin "example" test) generated 12 warnings
[INFO] [stderr] warning: `rust_fs_io` (bin "serialize_text" test) generated 3 warnings
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.09s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/example-19a90caf37875d19)
[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; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/serialize_binary-161d55de1d19e6ca)
[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; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/serialize_text-78be2f92eac21402)
[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; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "12cc7b8060919d77cdf3ff820e678992acd0d294ffaa82f5600eb7c51f46bf11", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "12cc7b8060919d77cdf3ff820e678992acd0d294ffaa82f5600eb7c51f46bf11", kill_on_drop: false }`
[INFO] [stdout] 12cc7b8060919d77cdf3ff820e678992acd0d294ffaa82f5600eb7c51f46bf11