[INFO] cloning repository https://github.com/Lukman-01/rust-learn-by-practice
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Lukman-01/rust-learn-by-practice" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLukman-01%2Frust-learn-by-practice", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLukman-01%2Frust-learn-by-practice'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c49e3c05a5615b27ff984fc371233f6ce0e96e00
[INFO] testing Lukman-01/rust-learn-by-practice against master#1ddedbaa5919b7b3e70d984660e21e844c615c97 for pr-128400
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLukman-01%2Frust-learn-by-practice" "/workspace/builds/worker-0-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Lukman-01/rust-learn-by-practice on toolchain 1ddedbaa5919b7b3e70d984660e21e844c615c97
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1ddedbaa5919b7b3e70d984660e21e844c615c97" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Lukman-01/rust-learn-by-practice
[INFO] finished tweaking git repo https://github.com/Lukman-01/rust-learn-by-practice
[INFO] tweaked toml for git repo https://github.com/Lukman-01/rust-learn-by-practice written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/Lukman-01/rust-learn-by-practice 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" "+1ddedbaa5919b7b3e70d984660e21e844c615c97" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[ERROR] error running command: no output for 300 seconds
[ERROR] this task or one of its parent failed!
[ERROR] no output for 300 seconds
[ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace.
[INFO] testing Lukman-01/rust-learn-by-practice against try#33f1d8bb92813a1bfc23c093c9f443ab09290307 for pr-128400
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLukman-01%2Frust-learn-by-practice" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Lukman-01/rust-learn-by-practice on toolchain 33f1d8bb92813a1bfc23c093c9f443ab09290307
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+33f1d8bb92813a1bfc23c093c9f443ab09290307" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Lukman-01/rust-learn-by-practice
[INFO] finished tweaking git repo https://github.com/Lukman-01/rust-learn-by-practice
[INFO] tweaked toml for git repo https://github.com/Lukman-01/rust-learn-by-practice written to /workspace/builds/worker-0-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/Lukman-01/rust-learn-by-practice 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" "+33f1d8bb92813a1bfc23c093c9f443ab09290307" "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-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+33f1d8bb92813a1bfc23c093c9f443ab09290307" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ded770a249da91ecc62a48db0714d207809015d2c78e8428a3a9c137b1b7ff96
[INFO] running `Command { std: "docker" "start" "-a" "ded770a249da91ecc62a48db0714d207809015d2c78e8428a3a9c137b1b7ff96", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ded770a249da91ecc62a48db0714d207809015d2c78e8428a3a9c137b1b7ff96", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ded770a249da91ecc62a48db0714d207809015d2c78e8428a3a9c137b1b7ff96", kill_on_drop: false }`
[INFO] [stdout] ded770a249da91ecc62a48db0714d207809015d2c78e8428a3a9c137b1b7ff96
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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" "-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" "+33f1d8bb92813a1bfc23c093c9f443ab09290307" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] fec109a3fead98d870192879ad8eb344cc282f2f8fa627100ddbe549d8d4cebe
[INFO] running `Command { std: "docker" "start" "-a" "fec109a3fead98d870192879ad8eb344cc282f2f8fa627100ddbe549d8d4cebe", kill_on_drop: false }`
[INFO] [stderr]    Compiling rust-learn-by-practice v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused label
[INFO] [stdout]   --> src/Flow_Control/flowcontrol11.rs:48:9
[INFO] [stdout]    |
[INFO] [stdout] 48 |         'inner2: loop {
[INFO] [stdout]    |         ^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_labels)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0499]: cannot borrow `s` as mutable more than once at a time
[INFO] [stdout]   --> src/ownership_and_borrowing/ref_and_borrowing/ref_and_borrowing11.rs:17:14
[INFO] [stdout]    |
[INFO] [stdout] 16 |     let r1 = &mut s;
[INFO] [stdout]    |              ------ first mutable borrow occurs here
[INFO] [stdout] 17 |     let r2 = &mut s;
[INFO] [stdout]    |              ^^^^^^ second mutable borrow occurs here
[INFO] [stdout] ...
[INFO] [stdout] 20 |     println!("{}, {}", r1, r2);
[INFO] [stdout]    |                        -- first borrow later used here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: irrefutable `if let` pattern
[INFO] [stdout]   --> src/Pattern_matching/match_and_iflet/match7.rs:26:8
[INFO] [stdout]    |
[INFO] [stdout] 26 |     if let Foo::Bar(i) = a {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this pattern will always match, so the `if let` is useless
[INFO] [stdout]    = help: consider replacing the `if let` with a `let`
[INFO] [stdout]    = note: `#[warn(irrefutable_let_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/collectionTypes/Strings/string2.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 26 |     let mut s = String::from("hello, world");
[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/collectionTypes/Strings/string7.rs:36:5
[INFO] [stdout]    |
[INFO] [stdout] 36 | let mut story = mem::ManuallyDrop::new(story);
[INFO] [stdout]    |     ----^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `width`
[INFO] [stdout]   --> src/formated_output/formating/formating9.rs:38:10
[INFO] [stdout]    |
[INFO] [stdout] 38 |     let (width, precision) = get_format();
[INFO] [stdout]    |          ^^^^^ help: if this is intentional, prefix it with an underscore: `_width`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `precision`
[INFO] [stdout]   --> src/formated_output/formating/formating9.rs:38:17
[INFO] [stdout]    |
[INFO] [stdout] 38 |     let (width, precision) = get_format();
[INFO] [stdout]    |                 ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_precision`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> src/lifetime/basic10.rs:11:32
[INFO] [stdout]    |
[INFO] [stdout] 11 | fn longest<'a, 'b>(x: &'a str, y: &'b str) -> &'a str {
[INFO] [stdout]    |                                ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> src/lifetime/basic5.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |     let y: &i32 = &_x;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 1 previous error; 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0499`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rust-learn-by-practice` (bin "rust-learn-by-practice") due to 2 previous errors; 8 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "fec109a3fead98d870192879ad8eb344cc282f2f8fa627100ddbe549d8d4cebe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fec109a3fead98d870192879ad8eb344cc282f2f8fa627100ddbe549d8d4cebe", kill_on_drop: false }`
[INFO] [stdout] fec109a3fead98d870192879ad8eb344cc282f2f8fa627100ddbe549d8d4cebe