[INFO] fetching crate av-bitstream 0.1.2...
[INFO] checking av-bitstream-0.1.2 against beta-2021-10-15 for beta-1.56-3
[INFO] extracting crate av-bitstream 0.1.2 into /workspace/builds/worker-77/source
[INFO] validating manifest of crates.io crate av-bitstream 0.1.2 on toolchain beta-2021-10-15
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-10-15" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate av-bitstream 0.1.2
[INFO] finished tweaking crates.io crate av-bitstream 0.1.2
[INFO] tweaked toml for crates.io crate av-bitstream 0.1.2 written to /workspace/builds/worker-77/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-10-15" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-10-15" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-77/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-77/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-10-15" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b95cc88f8518629e06823b8204803af030e028b97138ece7780d7e3b9205bf64
[INFO] running `Command { std: "docker" "start" "-a" "b95cc88f8518629e06823b8204803af030e028b97138ece7780d7e3b9205bf64", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b95cc88f8518629e06823b8204803af030e028b97138ece7780d7e3b9205bf64", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b95cc88f8518629e06823b8204803af030e028b97138ece7780d7e3b9205bf64", kill_on_drop: false }`
[INFO] [stdout] b95cc88f8518629e06823b8204803af030e028b97138ece7780d7e3b9205bf64
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-77/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-77/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=warn" "-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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-10-15" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] fc879fa540244b47deb4af7313864b6bcfc44f168aac6111884d5e4a84513c98
[INFO] running `Command { std: "docker" "start" "-a" "fc879fa540244b47deb4af7313864b6bcfc44f168aac6111884d5e4a84513c98", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling version_check v0.9.3
[INFO] [stderr]    Compiling rustversion v1.0.5
[INFO] [stderr]    Compiling proc-macro-hack v0.5.19
[INFO] [stderr]     Checking assert_matches v1.5.0
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling err-derive v0.2.4
[INFO] [stderr]    Compiling paste-impl v0.1.18
[INFO] [stderr]     Checking paste v0.1.18
[INFO] [stderr]     Checking av-bitstream v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:4:9
[INFO] [stdout]    |
[INFO] [stdout] 4  |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 27 |     write_bytes_le!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_le` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 4  |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 32 |     write_bytes_be!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_be` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 11 |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:4:9
[INFO] [stdout]    |
[INFO] [stdout] 4  |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 37 |     write_bytes_le!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_le` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 4  |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 42 |     write_bytes_be!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_be` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 11 |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:4:9
[INFO] [stdout]    |
[INFO] [stdout] 4  |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 47 |     write_bytes_le!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_le` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 4  |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 52 |     write_bytes_be!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_be` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 11 |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:4:9
[INFO] [stdout]    |
[INFO] [stdout] 4  |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 87 |     write_bytes_le!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_le` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 4  |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 92 |     write_bytes_be!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_be` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 11 |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:4:9
[INFO] [stdout]    |
[INFO] [stdout] 4  |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 97 |     write_bytes_le!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_le` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 4  |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/bytewrite.rs:11:9
[INFO] [stdout]     |
[INFO] [stdout] 11  |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 102 |     write_bytes_be!(buf, n);
[INFO] [stdout]     |     ------------------------ in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: this warning originates in the macro `write_bytes_be` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 11  |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 10 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:4:9
[INFO] [stdout]    |
[INFO] [stdout] 4  |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 27 |     write_bytes_le!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_le` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 4  |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 32 |     write_bytes_be!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_be` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 11 |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:4:9
[INFO] [stdout]    |
[INFO] [stdout] 4  |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 37 |     write_bytes_le!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_le` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 4  |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 42 |     write_bytes_be!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_be` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 11 |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:4:9
[INFO] [stdout]    |
[INFO] [stdout] 4  |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 47 |     write_bytes_le!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_le` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 4  |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 52 |     write_bytes_be!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_be` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 11 |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:4:9
[INFO] [stdout]    |
[INFO] [stdout] 4  |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 87 |     write_bytes_le!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_le` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 4  |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 92 |     write_bytes_be!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_be` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 11 |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/bytewrite.rs:4:9
[INFO] [stdout]    |
[INFO] [stdout] 4  |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 97 |     write_bytes_le!(buf, n);
[INFO] [stdout]    |     ------------------------ in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `write_bytes_le` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 4  |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/bytewrite.rs:11:9
[INFO] [stdout]     |
[INFO] [stdout] 11  |         &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout] ...
[INFO] [stdout] 102 |     write_bytes_be!(buf, n);
[INFO] [stdout]     |     ------------------------ in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: this warning originates in the macro `write_bytes_be` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 11  |         let _ = &mut $buf[..bytes.len()].copy_from_slice(&bytes);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 10 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 12.47s
[INFO] running `Command { std: "docker" "inspect" "fc879fa540244b47deb4af7313864b6bcfc44f168aac6111884d5e4a84513c98", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fc879fa540244b47deb4af7313864b6bcfc44f168aac6111884d5e4a84513c98", kill_on_drop: false }`
[INFO] [stdout] fc879fa540244b47deb4af7313864b6bcfc44f168aac6111884d5e4a84513c98
