[INFO] fetching crate prongs 0.0.5...
[INFO] checking prongs-0.0.5 against master#da897dfb6daa268a965d2d73620316ba56020a19 for pr-76219
[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 da897dfb6daa268a965d2d73620316ba56020a19
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+da897dfb6daa268a965d2d73620316ba56020a19" "read-manifest" "--manifest-path" "Cargo.toml", 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" "+da897dfb6daa268a965d2d73620316ba56020a19" "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" "+da897dfb6daa268a965d2d73620316ba56020a19" "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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+da897dfb6daa268a965d2d73620316ba56020a19" "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] a19365a8cfba8d2a632fffd34afaa99146678a4ca3205ac7bd6267d199f7f31c
[INFO] running `Command { std: "docker" "start" "-a" "a19365a8cfba8d2a632fffd34afaa99146678a4ca3205ac7bd6267d199f7f31c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a19365a8cfba8d2a632fffd34afaa99146678a4ca3205ac7bd6267d199f7f31c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a19365a8cfba8d2a632fffd34afaa99146678a4ca3205ac7bd6267d199f7f31c", kill_on_drop: false }`
[INFO] [stdout] a19365a8cfba8d2a632fffd34afaa99146678a4ca3205ac7bd6267d199f7f31c
[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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+da897dfb6daa268a965d2d73620316ba56020a19" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d3af5e932f0b8fea4dca545056fb4f31cc06c718beee89a3f36a8c80419285cd
[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" "d3af5e932f0b8fea4dca545056fb4f31cc06c718beee89a3f36a8c80419285cd", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.20
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling serde v1.0.115
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]    Compiling syn v1.0.40
[INFO] [stderr]    Compiling serde_derive v1.0.115
[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" "d3af5e932f0b8fea4dca545056fb4f31cc06c718beee89a3f36a8c80419285cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d3af5e932f0b8fea4dca545056fb4f31cc06c718beee89a3f36a8c80419285cd", kill_on_drop: false }`
[INFO] [stdout] d3af5e932f0b8fea4dca545056fb4f31cc06c718beee89a3f36a8c80419285cd