[INFO] cloning repository https://github.com/liurongdong/learn_rust_grammar
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/liurongdong/learn_rust_grammar" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fliurongdong%2Flearn_rust_grammar", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fliurongdong%2Flearn_rust_grammar'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 181b832ad3dd83f6c307cc920385e9248f51006d
[INFO] checking liurongdong/learn_rust_grammar against master#068609ce766e55d2e7371cd2a86143a6d7e8e2e4 for pr-138952
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fliurongdong%2Flearn_rust_grammar" "/workspace/builds/worker-5-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/liurongdong/learn_rust_grammar on toolchain 068609ce766e55d2e7371cd2a86143a6d7e8e2e4
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+068609ce766e55d2e7371cd2a86143a6d7e8e2e4" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/liurongdong/learn_rust_grammar
[INFO] finished tweaking git repo https://github.com/liurongdong/learn_rust_grammar
[INFO] tweaked toml for git repo https://github.com/liurongdong/learn_rust_grammar written to /workspace/builds/worker-5-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/liurongdong/learn_rust_grammar 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" "+068609ce766e55d2e7371cd2a86143a6d7e8e2e4" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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@sha256:4b26683ee3c49f365255c425c23003cbf4366de097804722c29c5bbbee3624d2" "/opt/rustwide/cargo-home/bin/cargo" "+068609ce766e55d2e7371cd2a86143a6d7e8e2e4" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 68f4fc8ded29f474e1124399843e8edc1c293c693d39a19d53fb6b3cfa43bba4
[INFO] running `Command { std: "docker" "start" "-a" "68f4fc8ded29f474e1124399843e8edc1c293c693d39a19d53fb6b3cfa43bba4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "68f4fc8ded29f474e1124399843e8edc1c293c693d39a19d53fb6b3cfa43bba4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "68f4fc8ded29f474e1124399843e8edc1c293c693d39a19d53fb6b3cfa43bba4", kill_on_drop: false }`
[INFO] [stdout] 68f4fc8ded29f474e1124399843e8edc1c293c693d39a19d53fb6b3cfa43bba4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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@sha256:4b26683ee3c49f365255c425c23003cbf4366de097804722c29c5bbbee3624d2" "/opt/rustwide/cargo-home/bin/cargo" "+068609ce766e55d2e7371cd2a86143a6d7e8e2e4" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e5172bc65d2e746f8f75fc8922fd2972f0d6f88a35ebc507c583a03f4d2f36c0
[INFO] running `Command { std: "docker" "start" "-a" "e5172bc65d2e746f8f75fc8922fd2972f0d6f88a35ebc507c583a03f4d2f36c0", kill_on_drop: false }`
[INFO] [stderr]     Checking untitled v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::ptr::write`
[INFO] [stdout]    --> src/formatted_print.rs:116:5
[INFO] [stdout]     |
[INFO] [stdout] 116 | use std::ptr::write;
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::ptr::write`
[INFO] [stdout]    --> src/formatted_print.rs:116:5
[INFO] [stdout]     |
[INFO] [stdout] 116 | use std::ptr::write;
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `c` is never read
[INFO] [stdout]   --> src/formatted_print.rs:64:13
[INFO] [stdout]    |
[INFO] [stdout] 64 |     let mut c = String::from("32233");
[INFO] [stdout]    |             ^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `c` is never read
[INFO] [stdout]   --> src/formatted_print.rs:64:13
[INFO] [stdout]    |
[INFO] [stdout] 64 |     let mut c = String::from("32233");
[INFO] [stdout]    |             ^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/formatted_print.rs:76:22
[INFO] [stdout]    |
[INFO] [stdout] 76 |     struct Structure(i32);
[INFO] [stdout]    |            --------- ^^^
[INFO] [stdout]    |            |
[INFO] [stdout]    |            field in this struct
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider removing this field
[INFO] [stdout]    = note: `Structure` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `name` and `age` are never read
[INFO] [stdout]   --> src/formatted_print.rs:93:5
[INFO] [stdout]    |
[INFO] [stdout] 92 | struct Person<'a>{
[INFO] [stdout]    |        ------ fields in this struct
[INFO] [stdout] 93 |     name: &'a str,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 94 |     age: u8
[INFO] [stdout]    |     ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Person` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/formatted_print.rs:76:22
[INFO] [stdout]    |
[INFO] [stdout] 76 |     struct Structure(i32);
[INFO] [stdout]    |            --------- ^^^
[INFO] [stdout]    |            |
[INFO] [stdout]    |            field in this struct
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider removing this field
[INFO] [stdout]    = note: `Structure` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `name` and `age` are never read
[INFO] [stdout]   --> src/formatted_print.rs:93:5
[INFO] [stdout]    |
[INFO] [stdout] 92 | struct Person<'a>{
[INFO] [stdout]    |        ------ fields in this struct
[INFO] [stdout] 93 |     name: &'a str,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 94 |     age: u8
[INFO] [stdout]    |     ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Person` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.19s
[INFO] running `Command { std: "docker" "inspect" "e5172bc65d2e746f8f75fc8922fd2972f0d6f88a35ebc507c583a03f4d2f36c0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e5172bc65d2e746f8f75fc8922fd2972f0d6f88a35ebc507c583a03f4d2f36c0", kill_on_drop: false }`
[INFO] [stdout] e5172bc65d2e746f8f75fc8922fd2972f0d6f88a35ebc507c583a03f4d2f36c0