[INFO] fetching crate symbolics_calculus 0.1.5...
[INFO] checking symbolics_calculus-0.1.5 against try#f6e2f78768c57172b99c3e85892f867894dc7e30 for pr-75502
[INFO] extracting crate symbolics_calculus 0.1.5 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate symbolics_calculus 0.1.5 on toolchain f6e2f78768c57172b99c3e85892f867894dc7e30
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "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-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded symbolics_core v0.1.5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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:e18d859f9e32a1da89bc7b2d7d51e13b57342044d1295d9fc0dd0068c58eb3d1" "/opt/rustwide/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b40809e525a64711923793664ed496e8ee88dd14205c0238d144a7e083ea4247
[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" "b40809e525a64711923793664ed496e8ee88dd14205c0238d144a7e083ea4247", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b40809e525a64711923793664ed496e8ee88dd14205c0238d144a7e083ea4247", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b40809e525a64711923793664ed496e8ee88dd14205c0238d144a7e083ea4247", kill_on_drop: false }`
[INFO] [stdout] b40809e525a64711923793664ed496e8ee88dd14205c0238d144a7e083ea4247
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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:e18d859f9e32a1da89bc7b2d7d51e13b57342044d1295d9fc0dd0068c58eb3d1" "/opt/rustwide/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 88d93b3d125dea9311cb6b2cd9b3f2c9b28ebfa0e82124f5119b7a7acc613336
[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" "88d93b3d125dea9311cb6b2cd9b3f2c9b28ebfa0e82124f5119b7a7acc613336", 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 struct `std::string::String`
[INFO] [stdout]    |                                           this method call resolves to `&T`
[INFO] [stdout]    |
[INFO] [stdout]    = note: cannot satisfy `std::string::String: std::convert::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 struct `std::string::String`
[INFO] [stdout]    |                                           this method call resolves to `&T`
[INFO] [stdout]    |
[INFO] [stdout]    = note: cannot satisfy `std::string::String: std::convert::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" "88d93b3d125dea9311cb6b2cd9b3f2c9b28ebfa0e82124f5119b7a7acc613336", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "88d93b3d125dea9311cb6b2cd9b3f2c9b28ebfa0e82124f5119b7a7acc613336", kill_on_drop: false }`
[INFO] [stdout] 88d93b3d125dea9311cb6b2cd9b3f2c9b28ebfa0e82124f5119b7a7acc613336