[INFO] cloning repository https://github.com/davidbarsky/tracing-reproduction
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/davidbarsky/tracing-reproduction" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdavidbarsky%2Ftracing-reproduction", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdavidbarsky%2Ftracing-reproduction'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 3663f47b17bf5c9f02a73fec6bf623ff562d35bd
[INFO] testing davidbarsky/tracing-reproduction against 1.49.0 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdavidbarsky%2Ftracing-reproduction" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/davidbarsky/tracing-reproduction on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/davidbarsky/tracing-reproduction
[INFO] finished tweaking git repo https://github.com/davidbarsky/tracing-reproduction
[INFO] tweaked toml for git repo https://github.com/davidbarsky/tracing-reproduction written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/davidbarsky/tracing-reproduction already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--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-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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "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] 5b6da71757c54bc126a1617cd871cc021e063d5be257f3927cb000896b5d65e0
[INFO] running `Command { std: "docker" "start" "-a" "5b6da71757c54bc126a1617cd871cc021e063d5be257f3927cb000896b5d65e0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5b6da71757c54bc126a1617cd871cc021e063d5be257f3927cb000896b5d65e0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5b6da71757c54bc126a1617cd871cc021e063d5be257f3927cb000896b5d65e0", kill_on_drop: false }`
[INFO] [stdout] 5b6da71757c54bc126a1617cd871cc021e063d5be257f3927cb000896b5d65e0
[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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ecb817670c520d19652c8b8a7c2c1c0a2c12465c4fd59bc26536471f25f54a3a
[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" "ecb817670c520d19652c8b8a7c2c1c0a2c12465c4fd59bc26536471f25f54a3a", 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] [stderr]    Compiling proc-macro2 v1.0.6
[INFO] [stderr]    Compiling syn v1.0.11
[INFO] [stderr]    Compiling lazy_static v1.4.0
[INFO] [stderr]    Compiling tracing-core v0.1.7
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]    Compiling tracing-attributes v0.1.5
[INFO] [stderr]    Compiling tracing v0.1.10
[INFO] [stderr]    Compiling tracing-reproduction v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0277]: the trait bound `Option<&'a Id>: From<Option<Id>>` is not satisfied
[INFO] [stdout]  --> src/main.rs:6:10
[INFO] [stdout]   |
[INFO] [stdout] 6 |     span.follows_from(curr.id());
[INFO] [stdout]   |          ^^^^^^^^^^^^ the trait `From<Option<Id>>` is not implemented for `Option<&'a Id>`
[INFO] [stdout]   |
[INFO] [stdout]   = help: the following implementations were found:
[INFO] [stdout]             <Option<&'a T> as From<&'a Option<T>>>
[INFO] [stdout]             <Option<&'a mut T> as From<&'a mut Option<T>>>
[INFO] [stdout]             <Option<T> as From<T>>
[INFO] [stdout]   = note: required because of the requirements on the impl of `for<'a> Into<Option<&'a Id>>` for `Option<Id>`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `tracing-reproduction`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "ecb817670c520d19652c8b8a7c2c1c0a2c12465c4fd59bc26536471f25f54a3a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ecb817670c520d19652c8b8a7c2c1c0a2c12465c4fd59bc26536471f25f54a3a", kill_on_drop: false }`
[INFO] [stdout] ecb817670c520d19652c8b8a7c2c1c0a2c12465c4fd59bc26536471f25f54a3a