[INFO] fetching crate mtcp 0.1.0...
[INFO] testing mtcp-0.1.0 against beta-2021-08-01 for beta-1.55-1
[INFO] extracting crate mtcp 0.1.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate mtcp 0.1.0 on toolchain beta-2021-08-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mtcp 0.1.0
[INFO] finished tweaking crates.io crate mtcp 0.1.0
[INFO] tweaked toml for crates.io crate mtcp 0.1.0 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded md5 v0.3.8
[INFO] [stderr]   Downloaded docopt v0.7.0
[INFO] [stderr]   Downloaded android_log-sys v0.1.2
[INFO] [stderr]   Downloaded android_logger v0.2.4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] da4b3cb5443782dcd41fa0f7ad4c07e9dcf7c6a573bcab4efbc28e2d80a305ed
[INFO] running `Command { std: "docker" "start" "-a" "da4b3cb5443782dcd41fa0f7ad4c07e9dcf7c6a573bcab4efbc28e2d80a305ed", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "da4b3cb5443782dcd41fa0f7ad4c07e9dcf7c6a573bcab4efbc28e2d80a305ed", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "da4b3cb5443782dcd41fa0f7ad4c07e9dcf7c6a573bcab4efbc28e2d80a305ed", kill_on_drop: false }`
[INFO] [stdout] da4b3cb5443782dcd41fa0f7ad4c07e9dcf7c6a573bcab4efbc28e2d80a305ed
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e4ac42c34cc7e69290246653d76726871638508873fee6b29b5a8193ea3b29d2
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "e4ac42c34cc7e69290246653d76726871638508873fee6b29b5a8193ea3b29d2", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling md5 v0.3.8
[INFO] [stderr]    Compiling mtcp v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]    Compiling docopt v0.7.0
[INFO] [stdout] warning: use of deprecated type alias `gcc::Config`: gcc::Config has been renamed to gcc::Build
[INFO] [stdout]  --> build.rs:5:10
[INFO] [stdout]   |
[INFO] [stdout] 5 |     gcc::Config::new()
[INFO] [stdout]   |          ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated type alias `gcc::Config`: gcc::Config has been renamed to gcc::Build
[INFO] [stdout]   --> build.rs:12:10
[INFO] [stdout]    |
[INFO] [stdout] 12 |     gcc::Config::new()
[INFO] [stdout]    |          ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `gcc::Build::new`: crate has been renamed to `cc`, the `gcc` name is not maintained
[INFO] [stdout]  --> build.rs:5:18
[INFO] [stdout]   |
[INFO] [stdout] 5 |     gcc::Config::new()
[INFO] [stdout]   |                  ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `gcc::Build::new`: crate has been renamed to `cc`, the `gcc` name is not maintained
[INFO] [stdout]   --> build.rs:12:18
[INFO] [stdout]    |
[INFO] [stdout] 12 |     gcc::Config::new()
[INFO] [stdout]    |                  ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] warning: cbits/checksum.c: In function 'ip_checksum_1':
[INFO] [stderr] warning: cbits/checksum.c:14:16: warning: comparison of integer expressions of different signedness: 'int' and 'unsigned int' [-Wsign-compare]
[INFO] [stderr] warning:    14 |  for (i = 0; i < size - 1; i += 2)
[INFO] [stderr] warning:       |                ^
[INFO] [stdout] warning: use of deprecated macro `RustcDecodable`: rustc-serialize is deprecated and no longer supported
[INFO] [stdout]   --> src/http_proxy_app.rs:56:17
[INFO] [stdout]    |
[INFO] [stdout] 56 | #[derive(Debug, RustcDecodable)]
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call resolves to `<&[T; N] as IntoIterator>::into_iter` (due to backwards compatibility), but will resolve to <[T; N] as IntoIterator>::into_iter in Rust 2021.
[INFO] [stdout]    --> src/structure/socket/tcp.rs:225:15
[INFO] [stdout]     |
[INFO] [stdout] 225 |         flags.into_iter()
[INFO] [stdout]     |               ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(array_into_iter)]` on by default
[INFO] [stdout]     = warning: this changes meaning in Rust 2021
[INFO] [stdout]     = note: for more information, see issue #66145 <https://github.com/rust-lang/rust/issues/66145>
[INFO] [stdout] help: use `.iter()` instead of `.into_iter()` to avoid ambiguity
[INFO] [stdout]     |
[INFO] [stdout] 225 |         flags.iter()
[INFO] [stdout]     |               ^^^^
[INFO] [stdout] help: or use `IntoIterator::into_iter(..)` instead of `.into_iter()` to explicitly iterate by value
[INFO] [stdout]     |
[INFO] [stdout] 225 |         IntoIterator::into_iter(flags)
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^     ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 9.47s
[INFO] running `Command { std: "docker" "inspect" "e4ac42c34cc7e69290246653d76726871638508873fee6b29b5a8193ea3b29d2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e4ac42c34cc7e69290246653d76726871638508873fee6b29b5a8193ea3b29d2", kill_on_drop: false }`
[INFO] [stdout] e4ac42c34cc7e69290246653d76726871638508873fee6b29b5a8193ea3b29d2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d31c6bc45339aefae3a3bb28538dbe1e7e165eb32c24a0cfd6d3f08f2a8ef601
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "d31c6bc45339aefae3a3bb28538dbe1e7e165eb32c24a0cfd6d3f08f2a8ef601", kill_on_drop: false }`
[INFO] [stderr] warning: cbits/checksum.c: In function 'ip_checksum_1':
[INFO] [stderr] warning: cbits/checksum.c:14:16: warning: comparison of integer expressions of different signedness: 'int' and 'unsigned int' [-Wsign-compare]
[INFO] [stderr] warning:    14 |  for (i = 0; i < size - 1; i += 2)
[INFO] [stderr] warning:       |                ^
[INFO] [stderr]    Compiling mtcp v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: use of deprecated type alias `gcc::Config`: gcc::Config has been renamed to gcc::Build
[INFO] [stdout]  --> build.rs:5:10
[INFO] [stdout]   |
[INFO] [stdout] 5 |     gcc::Config::new()
[INFO] [stdout]   |          ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated type alias `gcc::Config`: gcc::Config has been renamed to gcc::Build
[INFO] [stdout]   --> build.rs:12:10
[INFO] [stdout]    |
[INFO] [stdout] 12 |     gcc::Config::new()
[INFO] [stdout]    |          ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `gcc::Build::new`: crate has been renamed to `cc`, the `gcc` name is not maintained
[INFO] [stdout]  --> build.rs:5:18
[INFO] [stdout]   |
[INFO] [stdout] 5 |     gcc::Config::new()
[INFO] [stdout]   |                  ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `gcc::Build::new`: crate has been renamed to `cc`, the `gcc` name is not maintained
[INFO] [stdout]   --> build.rs:12:18
[INFO] [stdout]    |
[INFO] [stdout] 12 |     gcc::Config::new()
[INFO] [stdout]    |                  ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `RustcDecodable`: rustc-serialize is deprecated and no longer supported
[INFO] [stdout]   --> src/http_proxy_app.rs:56:17
[INFO] [stdout]    |
[INFO] [stdout] 56 | #[derive(Debug, RustcDecodable)]
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call resolves to `<&[T; N] as IntoIterator>::into_iter` (due to backwards compatibility), but will resolve to <[T; N] as IntoIterator>::into_iter in Rust 2021.
[INFO] [stdout]    --> src/structure/socket/tcp.rs:225:15
[INFO] [stdout]     |
[INFO] [stdout] 225 |         flags.into_iter()
[INFO] [stdout]     |               ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(array_into_iter)]` on by default
[INFO] [stdout]     = warning: this changes meaning in Rust 2021
[INFO] [stdout]     = note: for more information, see issue #66145 <https://github.com/rust-lang/rust/issues/66145>
[INFO] [stdout] help: use `.iter()` instead of `.into_iter()` to avoid ambiguity
[INFO] [stdout]     |
[INFO] [stdout] 225 |         flags.iter()
[INFO] [stdout]     |               ^^^^
[INFO] [stdout] help: or use `IntoIterator::into_iter(..)` instead of `.into_iter()` to explicitly iterate by value
[INFO] [stdout]     |
[INFO] [stdout] 225 |         IntoIterator::into_iter(flags)
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^     ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `RustcDecodable`: rustc-serialize is deprecated and no longer supported
[INFO] [stdout]   --> src/http_proxy_app.rs:56:17
[INFO] [stdout]    |
[INFO] [stdout] 56 | #[derive(Debug, RustcDecodable)]
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call resolves to `<&[T; N] as IntoIterator>::into_iter` (due to backwards compatibility), but will resolve to <[T; N] as IntoIterator>::into_iter in Rust 2021.
[INFO] [stdout]    --> src/structure/socket/tcp.rs:225:15
[INFO] [stdout]     |
[INFO] [stdout] 225 |         flags.into_iter()
[INFO] [stdout]     |               ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(array_into_iter)]` on by default
[INFO] [stdout]     = warning: this changes meaning in Rust 2021
[INFO] [stdout]     = note: for more information, see issue #66145 <https://github.com/rust-lang/rust/issues/66145>
[INFO] [stdout] help: use `.iter()` instead of `.into_iter()` to avoid ambiguity
[INFO] [stdout]     |
[INFO] [stdout] 225 |         flags.iter()
[INFO] [stdout]     |               ^^^^
[INFO] [stdout] help: or use `IntoIterator::into_iter(..)` instead of `.into_iter()` to explicitly iterate by value
[INFO] [stdout]     |
[INFO] [stdout] 225 |         IntoIterator::into_iter(flags)
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^     ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 2.37s
[INFO] running `Command { std: "docker" "inspect" "d31c6bc45339aefae3a3bb28538dbe1e7e165eb32c24a0cfd6d3f08f2a8ef601", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d31c6bc45339aefae3a3bb28538dbe1e7e165eb32c24a0cfd6d3f08f2a8ef601", kill_on_drop: false }`
[INFO] [stdout] d31c6bc45339aefae3a3bb28538dbe1e7e165eb32c24a0cfd6d3f08f2a8ef601
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "test" "--frozen", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 9e94b8d11859354180393fba8ab019fb9d4597028d07503522a11d5ab61a82ab
[INFO] running `Command { std: "docker" "start" "-a" "9e94b8d11859354180393fba8ab019fb9d4597028d07503522a11d5ab61a82ab", kill_on_drop: false }`
[INFO] [stderr] warning: use of deprecated type alias `gcc::Config`: gcc::Config has been renamed to gcc::Build
[INFO] [stderr]  --> build.rs:5:10
[INFO] [stderr]   |
[INFO] [stderr] 5 |     gcc::Config::new()
[INFO] [stderr]   |          ^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(deprecated)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated type alias `gcc::Config`: gcc::Config has been renamed to gcc::Build
[INFO] [stderr]   --> build.rs:12:10
[INFO] [stderr]    |
[INFO] [stderr] 12 |     gcc::Config::new()
[INFO] [stderr]    |          ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated associated function `gcc::Build::new`: crate has been renamed to `cc`, the `gcc` name is not maintained
[INFO] [stderr]  --> build.rs:5:18
[INFO] [stderr]   |
[INFO] [stderr] 5 |     gcc::Config::new()
[INFO] [stderr]   |                  ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated associated function `gcc::Build::new`: crate has been renamed to `cc`, the `gcc` name is not maintained
[INFO] [stderr]   --> build.rs:12:18
[INFO] [stderr]    |
[INFO] [stderr] 12 |     gcc::Config::new()
[INFO] [stderr]    |                  ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: `mtcp` (build script) generated 4 warnings
[INFO] [stderr] warning: cbits/checksum.c: In function 'ip_checksum_1':
[INFO] [stderr] warning: cbits/checksum.c:14:16: warning: comparison of integer expressions of different signedness: 'int' and 'unsigned int' [-Wsign-compare]
[INFO] [stderr] warning:    14 |  for (i = 0; i < size - 1; i += 2)
[INFO] [stderr] warning:       |                ^
[INFO] [stderr] warning: use of deprecated macro `RustcDecodable`: rustc-serialize is deprecated and no longer supported
[INFO] [stderr]   --> src/http_proxy_app.rs:56:17
[INFO] [stderr]    |
[INFO] [stderr] 56 | #[derive(Debug, RustcDecodable)]
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(deprecated)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: this method call resolves to `<&[T; N] as IntoIterator>::into_iter` (due to backwards compatibility), but will resolve to <[T; N] as IntoIterator>::into_iter in Rust 2021.
[INFO] [stderr]    --> src/structure/socket/tcp.rs:225:15
[INFO] [stderr]     |
[INFO] [stderr] 225 |         flags.into_iter()
[INFO] [stderr]     |               ^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(array_into_iter)]` on by default
[INFO] [stderr]     = warning: this changes meaning in Rust 2021
[INFO] [stderr]     = note: for more information, see issue #66145 <https://github.com/rust-lang/rust/issues/66145>
[INFO] [stderr] help: use `.iter()` instead of `.into_iter()` to avoid ambiguity
[INFO] [stderr]     |
[INFO] [stderr] 225 |         flags.iter()
[INFO] [stderr]     |               ^^^^
[INFO] [stderr] help: or use `IntoIterator::into_iter(..)` instead of `.into_iter()` to explicitly iterate by value
[INFO] [stderr]     |
[INFO] [stderr] 225 |         IntoIterator::into_iter(flags)
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^     ^
[INFO] [stderr] 
[INFO] [stderr] warning: `mtcp` (lib) generated 2 warnings
[INFO] [stderr] warning: `mtcp` (lib test) generated 2 warnings (2 duplicates)
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.03s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/mtcp-57581b003ab86bc9)
[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/mtcp-00c13846d1fba77b)
[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]    Doc-tests mtcp
[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" "9e94b8d11859354180393fba8ab019fb9d4597028d07503522a11d5ab61a82ab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9e94b8d11859354180393fba8ab019fb9d4597028d07503522a11d5ab61a82ab", kill_on_drop: false }`
[INFO] [stdout] 9e94b8d11859354180393fba8ab019fb9d4597028d07503522a11d5ab61a82ab
