[INFO] fetching crate prongs 0.0.5...
[INFO] testing prongs-0.0.5 against try#d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2 for pr-86479
[INFO] extracting crate prongs 0.0.5 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate prongs 0.0.5 on toolchain d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate prongs 0.0.5
[INFO] finished tweaking crates.io crate prongs 0.0.5
[INFO] tweaked toml for crates.io crate prongs 0.0.5 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded uuid v0.6.5
[INFO] [stderr]   Downloaded libudev-sys v0.1.4
[INFO] [stderr]   Downloaded gcc v0.3.55
[INFO] [stderr]   Downloaded nix v0.10.0
[INFO] [stderr]   Downloaded piston-float v0.3.0
[INFO] [stderr]   Downloaded piston-viewport v0.5.0
[INFO] [stderr]   Downloaded pistoncore-input v0.24.0
[INFO] [stderr]   Downloaded shader_version v0.3.0
[INFO] [stderr]   Downloaded piston v0.41.0
[INFO] [stderr]   Downloaded pistoncore-window v0.36.0
[INFO] [stderr]   Downloaded gilrs v0.6.3
[INFO] [stderr]   Downloaded pistoncore-event_loop v0.41.0
[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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8013a33a7587a4fbe9b6da6aece7fe2b7407d25d231e7cd0183a5ca6c46c9080
[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" "8013a33a7587a4fbe9b6da6aece7fe2b7407d25d231e7cd0183a5ca6c46c9080", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8013a33a7587a4fbe9b6da6aece7fe2b7407d25d231e7cd0183a5ca6c46c9080", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8013a33a7587a4fbe9b6da6aece7fe2b7407d25d231e7cd0183a5ca6c46c9080", kill_on_drop: false }`
[INFO] [stdout] 8013a33a7587a4fbe9b6da6aece7fe2b7407d25d231e7cd0183a5ca6c46c9080
[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=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" "+d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2" "build" "--frozen" "--message-format=json", 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] 3d1f38c6a1efccf9a95806048e84f99070821c5d72b387e1da7b55d77d84140d
[INFO] running `Command { std: "docker" "start" "-a" "3d1f38c6a1efccf9a95806048e84f99070821c5d72b387e1da7b55d77d84140d", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.74
[INFO] [stderr]    Compiling serde_derive v1.0.127
[INFO] [stderr]    Compiling serde v1.0.127
[INFO] [stderr]    Compiling prongs v0.0.5 (/opt/rustwide/workdir)
[INFO] [stdout] error: No backend selected, use features=<backend> in Cargo.toml or --features <backend> when building directly.
[INFO] [stdout]   --> src/lib.rs:14:1
[INFO] [stdout]    |
[INFO] [stdout] 14 | compile_error!("No backend selected, use features=<backend> in Cargo.toml or --features <backend> when building directly.");
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `prongs` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "3d1f38c6a1efccf9a95806048e84f99070821c5d72b387e1da7b55d77d84140d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3d1f38c6a1efccf9a95806048e84f99070821c5d72b387e1da7b55d77d84140d", kill_on_drop: false }`
[INFO] [stdout] 3d1f38c6a1efccf9a95806048e84f99070821c5d72b387e1da7b55d77d84140d