[INFO] fetching crate symbolics_calculus 0.1.5...
[INFO] checking symbolics_calculus-0.1.5 against master#b7ebc6b0c1ba3c27ebb17c0b496ece778ef11e18 for pr-79470
[INFO] extracting crate symbolics_calculus 0.1.5 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate symbolics_calculus 0.1.5 on toolchain b7ebc6b0c1ba3c27ebb17c0b496ece778ef11e18
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b7ebc6b0c1ba3c27ebb17c0b496ece778ef11e18" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate symbolics_calculus 0.1.5
[INFO] finished tweaking crates.io crate symbolics_calculus 0.1.5
[INFO] tweaked toml for crates.io crate symbolics_calculus 0.1.5 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b7ebc6b0c1ba3c27ebb17c0b496ece778ef11e18" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b7ebc6b0c1ba3c27ebb17c0b496ece778ef11e18" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+b7ebc6b0c1ba3c27ebb17c0b496ece778ef11e18" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0e15da0215b5ca31b8117d93c27a03f0dc290ce3e4a053587ed21334ff09766c
[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" "0e15da0215b5ca31b8117d93c27a03f0dc290ce3e4a053587ed21334ff09766c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0e15da0215b5ca31b8117d93c27a03f0dc290ce3e4a053587ed21334ff09766c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0e15da0215b5ca31b8117d93c27a03f0dc290ce3e4a053587ed21334ff09766c", kill_on_drop: false }`
[INFO] [stdout] 0e15da0215b5ca31b8117d93c27a03f0dc290ce3e4a053587ed21334ff09766c
[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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+b7ebc6b0c1ba3c27ebb17c0b496ece778ef11e18" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f386593458e0c420b4bf469f4ccf52cf88df0909d00880185467b074d6a383e9
[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" "f386593458e0c420b4bf469f4ccf52cf88df0909d00880185467b074d6a383e9", kill_on_drop: false }`
[INFO] [stderr]     Checking symbolics_core v0.1.5
[INFO] [stderr]     Checking symbolics_calculus v0.1.5 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `apply`, `s`
[INFO] [stdout]  --> src/lib.rs:3:22
[INFO] [stdout]   |
[INFO] [stdout] 3 | use symbolics_core::{s, apply};
[INFO] [stdout]   |                      ^  ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0283]: type annotations needed
[INFO] [stdout]   --> src/lib.rs:16:47
[INFO] [stdout]    |
[INFO] [stdout] 16 |             Add(a, b) => a.clone().deriv1(wrt.as_ref()) + b.clone().deriv1(wrt.as_ref()),
[INFO] [stdout]    |                                           ----^^^^^^--
[INFO] [stdout]    |                                           |   |
[INFO] [stdout]    |                                           |   cannot infer type for type parameter `T` declared on the trait `AsRef`
[INFO] [stdout]    |                                           this method call resolves to `&T`
[INFO] [stdout]    |
[INFO] [stdout]    = note: cannot satisfy `String: AsRef<_>`
[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 E0283`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `symbolics_calculus`
[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[E0283]: type annotations needed
[INFO] [stdout]   --> src/lib.rs:16:47
[INFO] [stdout]    |
[INFO] [stdout] 16 |             Add(a, b) => a.clone().deriv1(wrt.as_ref()) + b.clone().deriv1(wrt.as_ref()),
[INFO] [stdout]    |                                           ----^^^^^^--
[INFO] [stdout]    |                                           |   |
[INFO] [stdout]    |                                           |   cannot infer type for type parameter `T` declared on the trait `AsRef`
[INFO] [stdout]    |                                           this method call resolves to `&T`
[INFO] [stdout]    |
[INFO] [stdout]    = note: cannot satisfy `String: AsRef<_>`
[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 E0283`.
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "f386593458e0c420b4bf469f4ccf52cf88df0909d00880185467b074d6a383e9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f386593458e0c420b4bf469f4ccf52cf88df0909d00880185467b074d6a383e9", kill_on_drop: false }`
[INFO] [stdout] f386593458e0c420b4bf469f4ccf52cf88df0909d00880185467b074d6a383e9