[INFO] fetching crate back-to-the-future 0.1.7...
[INFO] testing back-to-the-future-0.1.7 against master#a77da2d454e6caa227a85b16410b95f93495e7e0 for pr-91031
[INFO] extracting crate back-to-the-future 0.1.7 into /workspace/builds/worker-110/source
[INFO] validating manifest of crates.io crate back-to-the-future 0.1.7 on toolchain a77da2d454e6caa227a85b16410b95f93495e7e0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate back-to-the-future 0.1.7
[INFO] finished tweaking crates.io crate back-to-the-future 0.1.7
[INFO] tweaked toml for crates.io crate back-to-the-future 0.1.7 written to /workspace/builds/worker-110/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "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-110/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-110/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] bd59b256bc826c290cb112f474959ec6d20c482a24a0ab6b88615417433c2c95
[INFO] running `Command { std: "docker" "start" "-a" "bd59b256bc826c290cb112f474959ec6d20c482a24a0ab6b88615417433c2c95", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bd59b256bc826c290cb112f474959ec6d20c482a24a0ab6b88615417433c2c95", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bd59b256bc826c290cb112f474959ec6d20c482a24a0ab6b88615417433c2c95", kill_on_drop: false }`
[INFO] [stdout] bd59b256bc826c290cb112f474959ec6d20c482a24a0ab6b88615417433c2c95
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-110/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-110/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4485d18116cf41e9f7d89b6757e805f000a3a32b3f405c5de9b40ba910865930
[INFO] running `Command { std: "docker" "start" "-a" "4485d18116cf41e9f7d89b6757e805f000a3a32b3f405c5de9b40ba910865930", kill_on_drop: false }`
[INFO] [stderr]    Compiling futures v0.1.31
[INFO] [stderr]    Compiling back-to-the-future v0.1.7 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]   --> src/lib.rs:36:12
[INFO] [stdout]    |
[INFO] [stdout] 36 | #![feature(await_macro)]
[INFO] [stdout]    |            ^^^^^^^^^^^ feature has been removed
[INFO] [stdout]    |
[INFO] [stdout]    = note: subsumed by `.await` syntax
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]   --> src/lib.rs:40:12
[INFO] [stdout]    |
[INFO] [stdout] 40 | #![feature(specialization)]
[INFO] [stdout]    |            ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]    = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout]    = help: consider using `min_specialization` instead, which is more stable and complete
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0557`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `back-to-the-future` due to 2 previous errors; 1 warning emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "4485d18116cf41e9f7d89b6757e805f000a3a32b3f405c5de9b40ba910865930", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4485d18116cf41e9f7d89b6757e805f000a3a32b3f405c5de9b40ba910865930", kill_on_drop: false }`
[INFO] [stdout] 4485d18116cf41e9f7d89b6757e805f000a3a32b3f405c5de9b40ba910865930