[INFO] fetching crate prongs 0.0.5...
[INFO] checking prongs-0.0.5 against try#ddfd70ee3c3748e597b32f416b0d15a4f6e37685 for pr-87050
[INFO] extracting crate prongs 0.0.5 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate prongs 0.0.5 on toolchain ddfd70ee3c3748e597b32f416b0d15a4f6e37685
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "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-5/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr] warning: spurious network error (2 tries remaining): [28] Timeout was reached (download of `pistoncore-window v0.36.0` failed to transfer more than 10 bytes in 30s)
[INFO] [stderr] warning: spurious network error (2 tries remaining): [28] Timeout was reached (failed to download any data for `piston v0.41.0` within 30s)
[INFO] [stderr] warning: spurious network error (1 tries remaining): [28] Timeout was reached (download of `pistoncore-window v0.36.0` failed to transfer more than 10 bytes in 30s)
[INFO] [stderr] warning: spurious network error (2 tries remaining): [28] Timeout was reached (failed to download any data for `pistoncore-event_loop v0.41.0` within 30s)
[INFO] [stderr]   Downloaded piston v0.41.0
[INFO] [stderr]   Downloaded pistoncore-window v0.36.0
[INFO] [stderr]   Downloaded pistoncore-event_loop v0.41.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 9e106d3db782688bc8cd0d5dd6d850823dca009d1ea9047b17d600f3d4049745
[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" "9e106d3db782688bc8cd0d5dd6d850823dca009d1ea9047b17d600f3d4049745", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9e106d3db782688bc8cd0d5dd6d850823dca009d1ea9047b17d600f3d4049745", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9e106d3db782688bc8cd0d5dd6d850823dca009d1ea9047b17d600f3d4049745", kill_on_drop: false }`
[INFO] [stdout] 9e106d3db782688bc8cd0d5dd6d850823dca009d1ea9047b17d600f3d4049745
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "check" "--frozen" "--all" "--all-targets" "--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] 8bcd08f55a69c7b5ba42e24f1730f68021dae155f93c8b1d601501e643f6f38b
[INFO] running `Command { std: "docker" "start" "-a" "8bcd08f55a69c7b5ba42e24f1730f68021dae155f93c8b1d601501e643f6f38b", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.73
[INFO] [stderr]    Compiling serde_derive v1.0.126
[INFO] [stderr]     Checking serde v1.0.126
[INFO] [stderr]     Checking 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: 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`
[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] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "8bcd08f55a69c7b5ba42e24f1730f68021dae155f93c8b1d601501e643f6f38b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8bcd08f55a69c7b5ba42e24f1730f68021dae155f93c8b1d601501e643f6f38b", kill_on_drop: false }`
[INFO] [stdout] 8bcd08f55a69c7b5ba42e24f1730f68021dae155f93c8b1d601501e643f6f38b