[INFO] updating cached repository https://github.com/vrcod/rust-pi-approximation
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/big/crater/work/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] cdfb33f9acef6dfccd7619bcde367b3f804148df
[INFO] testing vrcod/rust-pi-approximation against 1.38.0 for beta-1.39-1
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvrcod%2Frust-pi-approximation" "work/builds/worker-4/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/vrcod/rust-pi-approximation on toolchain 1.38.0
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/vrcod/rust-pi-approximation
[INFO] finished tweaking git repo https://github.com/vrcod/rust-pi-approximation
[INFO] tweaked toml for git repo https://github.com/vrcod/rust-pi-approximation written to work/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/vrcod/rust-pi-approximation already has a lockfile, it will not be regenerated
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr] error: the lock file /big/crater/work/builds/worker-4/source/Cargo.lock needs to be updated but --locked was passed to prevent this
[INFO] the lockfile is outdated, regenerating it
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.38.0" "build" "--frozen"`
[INFO] [stdout] dc0b3e8921635b3995b2ecc602382c879f84865916c19ebf30132db1f4ec12aa
[INFO] running `"docker" "start" "-a" "dc0b3e8921635b3995b2ecc602382c879f84865916c19ebf30132db1f4ec12aa"`
[INFO] [stderr] warning: An explicit [[bin]] section is specified in Cargo.toml which currently
[INFO] [stderr] disables Cargo from automatically inferring other binary targets.
[INFO] [stderr] This inference behavior will change in the Rust 2018 edition and the following
[INFO] [stderr] files will be included as a binary target:
[INFO] [stderr] 
[INFO] [stderr] * /opt/rustwide/workdir/src/main.rs
[INFO] [stderr] 
[INFO] [stderr] This is likely to break cargo build or cargo test as these files may not be
[INFO] [stderr] ready to be compiled as a binary target today. You can future-proof yourself
[INFO] [stderr] and disable this warning by adding `autobins = false` to your [package]
[INFO] [stderr] section. You may also move the files to a location where Cargo would not
[INFO] [stderr] automatically infer them to be a target, such as in subfolders.
[INFO] [stderr] 
[INFO] [stderr] For more information on this warning you can consult
[INFO] [stderr] https://github.com/rust-lang/cargo/issues/5330
[INFO] [stderr]    Compiling rust-stream v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/bin/two_threads.rs:20:4
[INFO] [stderr]    |
[INFO] [stderr] 20 |             task1.send(p);
[INFO] [stderr]    |             ^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/bin/two_threads.rs:30:4
[INFO] [stderr]    |
[INFO] [stderr] 30 |             task2.send(p);
[INFO] [stderr]    |             ^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/bin/max_threads.rs:20:4
[INFO] [stderr]    |
[INFO] [stderr] 20 |             task.send(p);
[INFO] [stderr]    |             ^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.50s
[INFO] running `"docker" "inspect" "dc0b3e8921635b3995b2ecc602382c879f84865916c19ebf30132db1f4ec12aa"`
[INFO] running `"docker" "rm" "-f" "dc0b3e8921635b3995b2ecc602382c879f84865916c19ebf30132db1f4ec12aa"`
[INFO] [stdout] dc0b3e8921635b3995b2ecc602382c879f84865916c19ebf30132db1f4ec12aa
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.38.0" "test" "--frozen" "--no-run"`
[INFO] [stdout] e3a6b11465626f0c5361913ce7cfa5352d858290d4ebdfeff2f0d85a353aee1b
[INFO] running `"docker" "start" "-a" "e3a6b11465626f0c5361913ce7cfa5352d858290d4ebdfeff2f0d85a353aee1b"`
[INFO] [stderr] warning: An explicit [[bin]] section is specified in Cargo.toml which currently
[INFO] [stderr] disables Cargo from automatically inferring other binary targets.
[INFO] [stderr] This inference behavior will change in the Rust 2018 edition and the following
[INFO] [stderr] files will be included as a binary target:
[INFO] [stderr] 
[INFO] [stderr] * /opt/rustwide/workdir/src/main.rs
[INFO] [stderr] 
[INFO] [stderr] This is likely to break cargo build or cargo test as these files may not be
[INFO] [stderr] ready to be compiled as a binary target today. You can future-proof yourself
[INFO] [stderr] and disable this warning by adding `autobins = false` to your [package]
[INFO] [stderr] section. You may also move the files to a location where Cargo would not
[INFO] [stderr] automatically infer them to be a target, such as in subfolders.
[INFO] [stderr] 
[INFO] [stderr] For more information on this warning you can consult
[INFO] [stderr] https://github.com/rust-lang/cargo/issues/5330
[INFO] [stderr]    Compiling rust-stream v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/bin/two_threads.rs:20:4
[INFO] [stderr]    |
[INFO] [stderr] 20 |             task1.send(p);
[INFO] [stderr]    |             ^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/bin/two_threads.rs:30:4
[INFO] [stderr]    |
[INFO] [stderr] 30 |             task2.send(p);
[INFO] [stderr]    |             ^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/bin/max_threads.rs:20:4
[INFO] [stderr]    |
[INFO] [stderr] 20 |             task.send(p);
[INFO] [stderr]    |             ^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.32s
[INFO] running `"docker" "inspect" "e3a6b11465626f0c5361913ce7cfa5352d858290d4ebdfeff2f0d85a353aee1b"`
[INFO] running `"docker" "rm" "-f" "e3a6b11465626f0c5361913ce7cfa5352d858290d4ebdfeff2f0d85a353aee1b"`
[INFO] [stdout] e3a6b11465626f0c5361913ce7cfa5352d858290d4ebdfeff2f0d85a353aee1b
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.38.0" "test" "--frozen"`
[INFO] [stdout] dc2e5aa4d315130ec317af11cc34653606682935e366082ec73fa2492d87632b
[INFO] running `"docker" "start" "-a" "dc2e5aa4d315130ec317af11cc34653606682935e366082ec73fa2492d87632b"`
[INFO] [stderr] warning: An explicit [[bin]] section is specified in Cargo.toml which currently
[INFO] [stderr] disables Cargo from automatically inferring other binary targets.
[INFO] [stderr] This inference behavior will change in the Rust 2018 edition and the following
[INFO] [stderr] files will be included as a binary target:
[INFO] [stderr] 
[INFO] [stderr] * /opt/rustwide/workdir/src/main.rs
[INFO] [stderr] 
[INFO] [stderr] This is likely to break cargo build or cargo test as these files may not be
[INFO] [stderr] ready to be compiled as a binary target today. You can future-proof yourself
[INFO] [stderr] and disable this warning by adding `autobins = false` to your [package]
[INFO] [stderr] section. You may also move the files to a location where Cargo would not
[INFO] [stderr] automatically infer them to be a target, such as in subfolders.
[INFO] [stderr] 
[INFO] [stderr] For more information on this warning you can consult
[INFO] [stderr] https://github.com/rust-lang/cargo/issues/5330
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/max_threads-b156b51c2250ef0f
[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
[INFO] [stdout] 
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/single_thread-8e4652eb7c8494af
[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
[INFO] [stdout] 
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/two_threads-10eac47398feae89
[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
[INFO] [stdout] 
[INFO] running `"docker" "inspect" "dc2e5aa4d315130ec317af11cc34653606682935e366082ec73fa2492d87632b"`
[INFO] running `"docker" "rm" "-f" "dc2e5aa4d315130ec317af11cc34653606682935e366082ec73fa2492d87632b"`
[INFO] [stdout] dc2e5aa4d315130ec317af11cc34653606682935e366082ec73fa2492d87632b