[INFO] cloning repository https://github.com/mlsteele/bittles
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/mlsteele/bittles" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmlsteele%2Fbittles", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmlsteele%2Fbittles'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 68441273c2e5aaa5e7e19d35c2b8fdeee0ac92af
[INFO] checking mlsteele/bittles against master#dfd7b8d03fb93d0e03147d28b3be6d93260fa94d for pr-87050
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmlsteele%2Fbittles" "/workspace/builds/worker-12/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-12/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/mlsteele/bittles on toolchain dfd7b8d03fb93d0e03147d28b3be6d93260fa94d
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/mlsteele/bittles
[INFO] finished tweaking git repo https://github.com/mlsteele/bittles
[INFO] tweaked toml for git repo https://github.com/mlsteele/bittles written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate git repo https://github.com/mlsteele/bittles already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "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-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c9c44d91369cee8683478383edc6d243223c6fe8dc199c8f8ac0e980f840323f
[INFO] running `Command { std: "docker" "start" "-a" "c9c44d91369cee8683478383edc6d243223c6fe8dc199c8f8ac0e980f840323f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c9c44d91369cee8683478383edc6d243223c6fe8dc199c8f8ac0e980f840323f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c9c44d91369cee8683478383edc6d243223c6fe8dc199c8f8ac0e980f840323f", kill_on_drop: false }`
[INFO] [stdout] c9c44d91369cee8683478383edc6d243223c6fe8dc199c8f8ac0e980f840323f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "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" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4e388b205aaba18bc6489987489a5371f0c7cecf7b29fe5665955865dec17e9d
[INFO] running `Command { std: "docker" "start" "-a" "4e388b205aaba18bc6489987489a5371f0c7cecf7b29fe5665955865dec17e9d", kill_on_drop: false }`
[INFO] [stderr]     Checking libc v0.2.21
[INFO] [stderr]    Compiling gcc v0.3.45
[INFO] [stderr]     Checking cfg-if v0.1.0
[INFO] [stderr]    Compiling rayon-core v1.0.0
[INFO] [stderr]     Checking log v0.3.7
[INFO] [stderr]    Compiling backtrace v0.3.0
[INFO] [stderr]     Checking matches v0.1.4
[INFO] [stderr]     Checking unicode-normalization v0.1.4
[INFO] [stderr]     Checking rustc-serialize v0.3.23
[INFO] [stderr]     Checking lazycell v0.4.0
[INFO] [stderr]     Checking futures v0.1.13
[INFO] [stderr]     Checking slog v2.0.5
[INFO] [stderr]     Checking take_mut v0.1.3
[INFO] [stderr]     Checking serde v0.9.15
[INFO] [stderr]     Checking either v1.1.0
[INFO] [stderr]     Checking scoped-tls v0.1.0
[INFO] [stderr]     Checking typeable v0.1.2
[INFO] [stderr]     Checking httparse v1.2.2
[INFO] [stderr]     Checking untrusted v0.3.2
[INFO] [stderr]    Compiling unicase v1.4.0
[INFO] [stderr]    Compiling hyper v0.10.8
[INFO] [stderr]    Compiling serde_codegen_internals v0.14.2
[INFO] [stderr]     Checking unicode-bidi v0.2.5
[INFO] [stderr]     Checking itertools v0.6.0
[INFO] [stderr]     Checking mime v0.2.3
[INFO] [stderr]    Compiling rand v0.3.15
[INFO] [stderr]    Compiling num_cpus v1.3.0
[INFO] [stdout] error[E0446]: private type `NeverStruct` in public interface
[INFO] [stdout]     --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/slog-2.0.5/src/lib.rs:1180:5
[INFO] [stdout]      |
[INFO] [stdout] 1180 |     type Err = Never;
[INFO] [stdout]      |     ^^^^^^^^^^^^^^^^^ can't leak private type
[INFO] [stdout] ...
[INFO] [stdout] 2868 | struct NeverStruct(());
[INFO] [stdout]      | ----------------------- `NeverStruct` declared as private
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0446]: private type `NeverStruct` in public interface
[INFO] [stdout]     --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/slog-2.0.5/src/lib.rs:1465:5
[INFO] [stdout]      |
[INFO] [stdout] 1465 |     type Err = Never;
[INFO] [stdout]      |     ^^^^^^^^^^^^^^^^^ can't leak private type
[INFO] [stdout] ...
[INFO] [stdout] 2868 | struct NeverStruct(());
[INFO] [stdout]      | ----------------------- `NeverStruct` declared as private
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0446]: private type `NeverStruct` in public interface
[INFO] [stdout]     --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/slog-2.0.5/src/lib.rs:1630:5
[INFO] [stdout]      |
[INFO] [stdout] 1630 |     type Err = Never;
[INFO] [stdout]      |     ^^^^^^^^^^^^^^^^^ can't leak private type
[INFO] [stdout] ...
[INFO] [stdout] 2868 | struct NeverStruct(());
[INFO] [stdout]      | ----------------------- `NeverStruct` declared as private
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0446]: private type `NeverStruct` in public interface
[INFO] [stdout]     --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/slog-2.0.5/src/lib.rs:1662:5
[INFO] [stdout]      |
[INFO] [stdout] 1662 |     type Err = Never;
[INFO] [stdout]      |     ^^^^^^^^^^^^^^^^^ can't leak private type
[INFO] [stdout] ...
[INFO] [stdout] 2868 | struct NeverStruct(());
[INFO] [stdout]      | ----------------------- `NeverStruct` declared as private
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0446`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `slog`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "4e388b205aaba18bc6489987489a5371f0c7cecf7b29fe5665955865dec17e9d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4e388b205aaba18bc6489987489a5371f0c7cecf7b29fe5665955865dec17e9d", kill_on_drop: false }`
[INFO] [stdout] 4e388b205aaba18bc6489987489a5371f0c7cecf7b29fe5665955865dec17e9d