[INFO] cloning repository https://github.com/lynn-hector/concurrency
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/lynn-hector/concurrency" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flynn-hector%2Fconcurrency", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flynn-hector%2Fconcurrency'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] cfeed67ca12dea558911024da7884449a5c7c299
[INFO] testing lynn-hector/concurrency against master#552a959051cebf8f88a8f558399baf733bec9ce0 for pr-136932
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flynn-hector%2Fconcurrency" "/workspace/builds/worker-6-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/lynn-hector/concurrency on toolchain 552a959051cebf8f88a8f558399baf733bec9ce0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+552a959051cebf8f88a8f558399baf733bec9ce0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/lynn-hector/concurrency
[INFO] finished tweaking git repo https://github.com/lynn-hector/concurrency
[INFO] tweaked toml for git repo https://github.com/lynn-hector/concurrency written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/lynn-hector/concurrency 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" "+552a959051cebf8f88a8f558399baf733bec9ce0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:3959728d45483eb673ba100a951a6b9f5012970368db2a9e08e0ac9b67c8a5ad" "/opt/rustwide/cargo-home/bin/cargo" "+552a959051cebf8f88a8f558399baf733bec9ce0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 72185f187c5a9c74f980f15250b5c4d13295fedc3eeb4b7a9f5c0d71f967034b
[INFO] running `Command { std: "docker" "start" "-a" "72185f187c5a9c74f980f15250b5c4d13295fedc3eeb4b7a9f5c0d71f967034b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "72185f187c5a9c74f980f15250b5c4d13295fedc3eeb4b7a9f5c0d71f967034b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "72185f187c5a9c74f980f15250b5c4d13295fedc3eeb4b7a9f5c0d71f967034b", kill_on_drop: false }`
[INFO] [stdout] 72185f187c5a9c74f980f15250b5c4d13295fedc3eeb4b7a9f5c0d71f967034b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:3959728d45483eb673ba100a951a6b9f5012970368db2a9e08e0ac9b67c8a5ad" "/opt/rustwide/cargo-home/bin/cargo" "+552a959051cebf8f88a8f558399baf733bec9ce0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d91c9017faecdacd1ca4ab212b9c05d3670c44077efdf37b2492658f999ff494
[INFO] running `Command { std: "docker" "start" "-a" "d91c9017faecdacd1ca4ab212b9c05d3670c44077efdf37b2492658f999ff494", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.92
[INFO] [stderr]    Compiling unicode-ident v1.0.14
[INFO] [stderr]    Compiling libc v0.2.169
[INFO] [stderr]    Compiling byteorder v1.5.0
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling anyhow v1.0.94
[INFO] [stderr]    Compiling oneshot v0.1.8
[INFO] [stderr]    Compiling quote v1.0.37
[INFO] [stderr]    Compiling syn v2.0.91
[INFO] [stderr]    Compiling getrandom v0.2.15
[INFO] [stderr]    Compiling rand_core v0.6.4
[INFO] [stderr]    Compiling zerocopy-derive v0.7.35
[INFO] [stderr]    Compiling zerocopy v0.7.35
[INFO] [stderr]    Compiling ppv-lite86 v0.2.20
[INFO] [stderr]    Compiling rand_chacha v0.3.1
[INFO] [stderr]    Compiling rand v0.8.5
[INFO] [stderr]    Compiling concurrency v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 7.47s
[INFO] running `Command { std: "docker" "inspect" "d91c9017faecdacd1ca4ab212b9c05d3670c44077efdf37b2492658f999ff494", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d91c9017faecdacd1ca4ab212b9c05d3670c44077efdf37b2492658f999ff494", kill_on_drop: false }`
[INFO] [stdout] d91c9017faecdacd1ca4ab212b9c05d3670c44077efdf37b2492658f999ff494
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:3959728d45483eb673ba100a951a6b9f5012970368db2a9e08e0ac9b67c8a5ad" "/opt/rustwide/cargo-home/bin/cargo" "+552a959051cebf8f88a8f558399baf733bec9ce0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 125990f97dd928c97545db3b51de3a5ef2c48099cab71674733a6bae9dab53f0
[INFO] running `Command { std: "docker" "start" "-a" "125990f97dd928c97545db3b51de3a5ef2c48099cab71674733a6bae9dab53f0", kill_on_drop: false }`
[INFO] [stderr]    Compiling concurrency v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> examples/metrics.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     metrics.inc("req.page.1");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 12 |     let _ = metrics.inc("req.page.1");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> examples/metrics.rs:13:5
[INFO] [stdout]    |
[INFO] [stdout] 13 |     metrics.inc("call.thread.work.1");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 13 |     let _ = metrics.inc("call.thread.work.1");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> examples/metrics.rs:16:9
[INFO] [stdout]    |
[INFO] [stdout] 16 |         task_worker(idx, metrics.clone());
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 16 |         let _ = task_worker(idx, metrics.clone());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> examples/metrics.rs:21:9
[INFO] [stdout]    |
[INFO] [stdout] 21 |         request_worker(metrics.clone());
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 21 |         let _ = request_worker(metrics.clone());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.73s
[INFO] running `Command { std: "docker" "inspect" "125990f97dd928c97545db3b51de3a5ef2c48099cab71674733a6bae9dab53f0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "125990f97dd928c97545db3b51de3a5ef2c48099cab71674733a6bae9dab53f0", kill_on_drop: false }`
[INFO] [stdout] 125990f97dd928c97545db3b51de3a5ef2c48099cab71674733a6bae9dab53f0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:3959728d45483eb673ba100a951a6b9f5012970368db2a9e08e0ac9b67c8a5ad" "/opt/rustwide/cargo-home/bin/cargo" "+552a959051cebf8f88a8f558399baf733bec9ce0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] dfe79d772b854fbba016d97ef9147c70a95a1c5c9af212812b13d1618e8366be
[INFO] running `Command { std: "docker" "start" "-a" "dfe79d772b854fbba016d97ef9147c70a95a1c5c9af212812b13d1618e8366be", kill_on_drop: false }`
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> examples/metrics.rs:12:5
[INFO] [stderr]    |
[INFO] [stderr] 12 |     metrics.inc("req.page.1");
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr] help: use `let _ = ...` to ignore the resulting value
[INFO] [stderr]    |
[INFO] [stderr] 12 |     let _ = metrics.inc("req.page.1");
[INFO] [stderr]    |     +++++++
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> examples/metrics.rs:13:5
[INFO] [stderr]    |
[INFO] [stderr] 13 |     metrics.inc("call.thread.work.1");
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] help: use `let _ = ...` to ignore the resulting value
[INFO] [stderr]    |
[INFO] [stderr] 13 |     let _ = metrics.inc("call.thread.work.1");
[INFO] [stderr]    |     +++++++
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> examples/metrics.rs:16:9
[INFO] [stderr]    |
[INFO] [stderr] 16 |         task_worker(idx, metrics.clone());
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] help: use `let _ = ...` to ignore the resulting value
[INFO] [stderr]    |
[INFO] [stderr] 16 |         let _ = task_worker(idx, metrics.clone());
[INFO] [stderr]    |         +++++++
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> examples/metrics.rs:21:9
[INFO] [stderr]    |
[INFO] [stderr] 21 |         request_worker(metrics.clone());
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] help: use `let _ = ...` to ignore the resulting value
[INFO] [stderr]    |
[INFO] [stderr] 21 |         let _ = request_worker(metrics.clone());
[INFO] [stderr]    |         +++++++
[INFO] [stderr] 
[INFO] [stderr] warning: `concurrency` (example "metrics") generated 4 warnings
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.03s
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/debug/deps/concurrency-5d28639537d4bbdc)
[INFO] [stdout] 
[INFO] [stdout] running 4 tests
[INFO] [stdout] test matrix::tests::test_a_can_not_multiply_b ... ok
[INFO] [stdout] test matrix::tests::test_matrix_display ... ok
[INFO] [stdout] test matrix::tests::test_matrix_multiply ... ok
[INFO] [stderr]      Running unittests src/main.rs (/opt/rustwide/target/debug/deps/concurrency-024f8fc7d0259e9e)
[INFO] [stdout] test matrix::tests::test_a_can_not_multiply_b_panic - should panic ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 4 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.02s
[INFO] [stdout] 
[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 concurrency
[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" "dfe79d772b854fbba016d97ef9147c70a95a1c5c9af212812b13d1618e8366be", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dfe79d772b854fbba016d97ef9147c70a95a1c5c9af212812b13d1618e8366be", kill_on_drop: false }`
[INFO] [stdout] dfe79d772b854fbba016d97ef9147c70a95a1c5c9af212812b13d1618e8366be