[INFO] updating cached repository https://github.com/mlsteele/bittles
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/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] 68441273c2e5aaa5e7e19d35c2b8fdeee0ac92af
[INFO] checking mlsteele/bittles against master#6dee5f1126dfd5c9314ee5ae9d9eb010e35ef257 for pr-70872
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmlsteele%2Fbittles" "/workspace/builds/worker-1/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/mlsteele/bittles on toolchain 6dee5f1126dfd5c9314ee5ae9d9eb010e35ef257
[INFO] running `"/workspace/cargo-home/bin/cargo" "+6dee5f1126dfd5c9314ee5ae9d9eb010e35ef257" "read-manifest" "--manifest-path" "Cargo.toml"`
[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-1/source/Cargo.toml
[INFO] crate git repo https://github.com/mlsteele/bittles already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+6dee5f1126dfd5c9314ee5ae9d9eb010e35ef257" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+6dee5f1126dfd5c9314ee5ae9d9eb010e35ef257" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] d5a0768e84f35a8ba8729d38e09d39676f91b74c8bf372c23f2e8580273f3b21
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `"docker" "start" "-a" "d5a0768e84f35a8ba8729d38e09d39676f91b74c8bf372c23f2e8580273f3b21"`
[INFO] [stderr]    Compiling gcc v0.3.45
[INFO] [stderr]    Compiling rayon-core v1.0.0
[INFO] [stderr]     Checking num-traits v0.1.37
[INFO] [stderr]    Compiling lazy_static v0.2.8
[INFO] [stderr]    Compiling backtrace v0.3.0
[INFO] [stderr]     Checking byteorder v1.0.0
[INFO] [stderr]     Checking rustc-demangle v0.1.4
[INFO] [stderr]     Checking regex-syntax v0.4.0
[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 strsim v0.6.0
[INFO] [stderr]     Checking httparse v1.2.2
[INFO] [stderr]     Checking untrusted v0.3.2
[INFO] [stderr]     Checking either v1.1.0
[INFO] [stderr]     Checking serde v0.9.15
[INFO] [stderr]     Checking scoped-tls v0.1.0
[INFO] [stderr]    Compiling rand v0.3.15
[INFO] [stderr]     Checking thread-id v3.0.0
[INFO] [stderr]     Checking iovec v0.1.0
[INFO] [stderr]     Checking net2 v0.2.27
[INFO] [stderr]     Checking isatty v0.1.3
[INFO] [stderr]    Compiling hyper v0.10.8
[INFO] [stderr]     Checking aho-corasick v0.6.3
[INFO] [stderr]     Checking itertools v0.6.0
[INFO] [stderr]     Checking idna v0.1.1
[INFO] [stderr]    Compiling serde_codegen_internals v0.14.2
[INFO] [stderr]     Checking thread_local v0.3.3
[INFO] [stderr]     Checking bytes v0.4.3
[INFO] [stderr] error[E0446]: private type `NeverStruct` in public interface
[INFO] [stderr]     --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/slog-2.0.5/src/lib.rs:1180:5
[INFO] [stderr]      |
[INFO] [stderr] 1180 |     type Err = Never;
[INFO] [stderr]      |     ^^^^^^^^^^^^^^^^^ can't leak private type
[INFO] [stderr] ...
[INFO] [stderr] 2868 | struct NeverStruct(());
[INFO] [stderr]      | - `NeverStruct` declared as private
[INFO] [stderr] 
[INFO] [stderr] error[E0446]: private type `NeverStruct` in public interface
[INFO] [stderr]     --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/slog-2.0.5/src/lib.rs:1465:5
[INFO] [stderr]      |
[INFO] [stderr] 1465 |     type Err = Never;
[INFO] [stderr]      |     ^^^^^^^^^^^^^^^^^ can't leak private type
[INFO] [stderr] ...
[INFO] [stderr] 2868 | struct NeverStruct(());
[INFO] [stderr]      | - `NeverStruct` declared as private
[INFO] [stderr] 
[INFO] [stderr] error[E0446]: private type `NeverStruct` in public interface
[INFO] [stderr]     --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/slog-2.0.5/src/lib.rs:1630:5
[INFO] [stderr]      |
[INFO] [stderr] 1630 |     type Err = Never;
[INFO] [stderr]      |     ^^^^^^^^^^^^^^^^^ can't leak private type
[INFO] [stderr] ...
[INFO] [stderr] 2868 | struct NeverStruct(());
[INFO] [stderr]      | - `NeverStruct` declared as private
[INFO] [stderr] 
[INFO] [stderr] error[E0446]: private type `NeverStruct` in public interface
[INFO] [stderr]     --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/slog-2.0.5/src/lib.rs:1662:5
[INFO] [stderr]      |
[INFO] [stderr] 1662 |     type Err = Never;
[INFO] [stderr]      |     ^^^^^^^^^^^^^^^^^ can't leak private type
[INFO] [stderr] ...
[INFO] [stderr] 2868 | struct NeverStruct(());
[INFO] [stderr]      | - `NeverStruct` declared as private
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 4 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0446`.
[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 `"docker" "inspect" "d5a0768e84f35a8ba8729d38e09d39676f91b74c8bf372c23f2e8580273f3b21"`
[INFO] running `"docker" "rm" "-f" "d5a0768e84f35a8ba8729d38e09d39676f91b74c8bf372c23f2e8580273f3b21"`
[INFO] [stdout] d5a0768e84f35a8ba8729d38e09d39676f91b74c8bf372c23f2e8580273f3b21