[INFO] cloning repository https://github.com/ndanaka/learning-systems-programming-in-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ndanaka/learning-systems-programming-in-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fndanaka%2Flearning-systems-programming-in-rust", kill_on_drop: false }`
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[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] aa2a54e6e926170f1a15d93ca876a37c6ce53257
[INFO] checking ndanaka/learning-systems-programming-in-rust against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fndanaka%2Flearning-systems-programming-in-rust" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }`
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[INFO] [stderr] done.
[INFO] removed /workspace/builds/worker-7-tc2/source/rust-toolchain
[INFO] started tweaking git repo https://github.com/ndanaka/learning-systems-programming-in-rust
[INFO] finished tweaking git repo https://github.com/ndanaka/learning-systems-programming-in-rust
[INFO] tweaked toml for git repo https://github.com/ndanaka/learning-systems-programming-in-rust written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/ndanaka/learning-systems-programming-in-rust 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 git repo https://github.com/ndanaka/learning-systems-programming-in-rust 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 }`
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[INFO] running `Command { std: "docker" "inspect" "ceb6f8a9d5cc3ef7a2f4a9a0652fe30a444407949b72935028286da2391f4cc4", kill_on_drop: false }`
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[INFO] [stdout] 0ebb8b7c8f3e3ff42ece65cb0f4b4a5dac07aa0c89897785a229fca20b3c88a7
[INFO] running `Command { std: "docker" "start" "-a" "0ebb8b7c8f3e3ff42ece65cb0f4b4a5dac07aa0c89897785a229fca20b3c88a7", kill_on_drop: false }`
[INFO] [stderr]    Compiling memchr v2.4.0
[INFO] [stderr]     Checking once_cell v1.7.2
[INFO] [stderr]     Checking regex-syntax v0.6.25
[INFO] [stderr]    Compiling libc v0.2.95
[INFO] [stderr]    Compiling proc-macro2 v1.0.26
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[INFO] [stderr]    Compiling cc v1.0.67
[INFO] [stderr]    Compiling anyhow v1.0.40
[INFO] [stderr]    Compiling httparse v1.4.1
[INFO] [stderr]    Compiling miniz_oxide v0.4.4
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling memoffset v0.6.4
[INFO] [stderr]     Checking walkdir v2.3.2
[INFO] [stderr]    Compiling crossbeam-utils v0.8.5
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.5
[INFO] [stderr]    Compiling rayon-core v1.9.1
[INFO] [stderr]    Compiling serde v1.0.126
[INFO] [stderr]    Compiling serde_json v1.0.64
[INFO] [stderr]    Compiling rayon v1.5.1
[INFO] [stderr]     Checking itoa v0.4.7
[INFO] [stderr]     Checking glob v0.3.0
[INFO] [stderr]    Compiling sysinfo v0.18.1
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[INFO] [stderr]     Checking aho-corasick v0.7.18
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[INFO] [stderr]     Checking chapter9 v0.1.0 (/opt/rustwide/workdir/chapter9)
[INFO] [stderr]     Checking chapter1 v0.1.0 (/opt/rustwide/workdir/chapter1)
[INFO] [stderr]     Checking appendix v0.1.0 (/opt/rustwide/workdir/appendix)
[INFO] [stderr]     Checking chapter8 v0.1.0 (/opt/rustwide/workdir/chapter8)
[INFO] [stderr]     Checking chapter6 v0.1.0 (/opt/rustwide/workdir/chapter6)
[INFO] [stderr]     Checking chapter14 v0.1.0 (/opt/rustwide/workdir/chapter14)
[INFO] [stderr]     Checking chapter16 v0.1.0 (/opt/rustwide/workdir/chapter16)
[INFO] [stderr]     Checking chapter17 v0.1.0 (/opt/rustwide/workdir/chapter17)
[INFO] [stderr]     Checking chapter13 v0.1.0 (/opt/rustwide/workdir/chapter13)
[INFO] [stderr]     Checking chapter15 v0.1.0 (/opt/rustwide/workdir/chapter15)
[INFO] [stderr]     Checking chapter5 v0.1.0 (/opt/rustwide/workdir/chapter5)
[INFO] [stderr]     Checking chapter12 v0.1.0 (/opt/rustwide/workdir/chapter12)
[INFO] [stderr]    Compiling thiserror-impl v1.0.24
[INFO] [stderr]    Compiling tokio-macros v1.2.0
[INFO] [stderr]     Checking chapter2 v0.1.0 (/opt/rustwide/workdir/chapter2)
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> chapter2/src/2_4_3/main.rs:6:13
[INFO] [stdout]   |
[INFO] [stdout] 6 |     IoError(std::io::Error),
[INFO] [stdout]   |     ------- ^^^^^^^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     field in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `BufferError` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]   |
[INFO] [stdout] 6 -     IoError(std::io::Error),
[INFO] [stdout] 6 +     IoError(()),
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> chapter2/src/2_4_3/main.rs:7:14
[INFO] [stdout]   |
[INFO] [stdout] 7 |     StrError(str::Utf8Error),
[INFO] [stdout]   |     -------- ^^^^^^^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     field in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `BufferError` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]   |
[INFO] [stdout] 7 -     StrError(str::Utf8Error),
[INFO] [stdout] 7 +     StrError(()),
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> chapter2/src/2_4_3/main.rs:6:13
[INFO] [stdout]   |
[INFO] [stdout] 6 |     IoError(std::io::Error),
[INFO] [stdout]   |     ------- ^^^^^^^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     field in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `BufferError` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]   |
[INFO] [stdout] 6 -     IoError(std::io::Error),
[INFO] [stdout] 6 +     IoError(()),
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> chapter2/src/2_4_3/main.rs:7:14
[INFO] [stdout]   |
[INFO] [stdout] 7 |     StrError(str::Utf8Error),
[INFO] [stdout]   |     -------- ^^^^^^^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     field in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `BufferError` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]   |
[INFO] [stdout] 7 -     StrError(str::Utf8Error),
[INFO] [stdout] 7 +     StrError(()),
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking thiserror v1.0.24
[INFO] [stderr]     Checking zip v0.5.12
[INFO] [stderr]     Checking chapter11 v0.1.0 (/opt/rustwide/workdir/chapter11)
[INFO] [stderr]     Checking chapter10 v0.1.0 (/opt/rustwide/workdir/chapter10)
[INFO] [stdout] warning: unreachable expression
[INFO] [stdout]   --> chapter11/src/11_8/main.rs:32:82
[INFO] [stdout]    |
[INFO] [stdout] 32 |             execve(&dir, &[dir.clone(), arg], &[env]).expect("execution failed.");
[INFO] [stdout]    |             ---------------------------------------------------------------------^ unreachable expression
[INFO] [stdout]    |             |
[INFO] [stdout]    |             any code following this expression is unreachable
[INFO] [stdout]    |
[INFO] [stdout] note: this expression has type `Infallible`, which is uninhabited
[INFO] [stdout]   --> chapter11/src/11_8/main.rs:32:13
[INFO] [stdout]    |
[INFO] [stdout] 32 |             execve(&dir, &[dir.clone(), arg], &[env]).expect("execution failed.");
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    = note: `#[warn(unreachable_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable expression
[INFO] [stdout]   --> chapter11/src/11_8/main.rs:32:82
[INFO] [stdout]    |
[INFO] [stdout] 32 |             execve(&dir, &[dir.clone(), arg], &[env]).expect("execution failed.");
[INFO] [stdout]    |             ---------------------------------------------------------------------^ unreachable expression
[INFO] [stdout]    |             |
[INFO] [stdout]    |             any code following this expression is unreachable
[INFO] [stdout]    |
[INFO] [stdout] note: this expression has type `Infallible`, which is uninhabited
[INFO] [stdout]   --> chapter11/src/11_8/main.rs:32:13
[INFO] [stdout]    |
[INFO] [stdout] 32 |             execve(&dir, &[dir.clone(), arg], &[env]).expect("execution failed.");
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    = note: `#[warn(unreachable_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking chapter3 v0.1.0 (/opt/rustwide/workdir/chapter3)
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> chapter3/src/3_6_2/main.rs:17:35
[INFO] [stdout]    |
[INFO] [stdout] 17 |         ($(iter.next().map(|word| word.parse::<$x>().ok().expect(&format!("couldn't parse {}", word))).unwrap(),)*)
[INFO] [stdout]    |                                   ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 24 |     let (i, f, g, s) = scan!(SOURCE, char::is_whitespace, i32, f64, f64, String);
[INFO] [stdout]    |                        --------------------------------------------------------- in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout]    = note: this error originates in the macro `scan` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `chapter3` (bin "3_6_2" test) due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> chapter3/src/3_6_2/main.rs:17:35
[INFO] [stdout]    |
[INFO] [stdout] 17 |         ($(iter.next().map(|word| word.parse::<$x>().ok().expect(&format!("couldn't parse {}", word))).unwrap(),)*)
[INFO] [stdout]    |                                   ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 24 |     let (i, f, g, s) = scan!(SOURCE, char::is_whitespace, i32, f64, f64, String);
[INFO] [stdout]    |                        --------------------------------------------------------- in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout]    = note: this error originates in the macro `scan` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `chapter3` (bin "3_6_2") due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "0ebb8b7c8f3e3ff42ece65cb0f4b4a5dac07aa0c89897785a229fca20b3c88a7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0ebb8b7c8f3e3ff42ece65cb0f4b4a5dac07aa0c89897785a229fca20b3c88a7", kill_on_drop: false }`
[INFO] [stdout] 0ebb8b7c8f3e3ff42ece65cb0f4b4a5dac07aa0c89897785a229fca20b3c88a7
