[INFO] crate sp-rpc 2.0.0-rc4 is already in cache
[INFO] checking sp-rpc-2.0.0-rc4 against master#1557fb031b272b4c5bfcc7de5df7eddc7b36a584 for pr-73166
[INFO] extracting crate sp-rpc 2.0.0-rc4 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate sp-rpc 2.0.0-rc4 on toolchain 1557fb031b272b4c5bfcc7de5df7eddc7b36a584
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1557fb031b272b4c5bfcc7de5df7eddc7b36a584" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate sp-rpc 2.0.0-rc4
[INFO] finished tweaking crates.io crate sp-rpc 2.0.0-rc4
[INFO] tweaked toml for crates.io crate sp-rpc 2.0.0-rc4 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1557fb031b272b4c5bfcc7de5df7eddc7b36a584" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1557fb031b272b4c5bfcc7de5df7eddc7b36a584" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+1557fb031b272b4c5bfcc7de5df7eddc7b36a584" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 000edb90b0c212b384a7e908fdf00259e395cd4565f66c46d9f4776b84d48646
[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" "000edb90b0c212b384a7e908fdf00259e395cd4565f66c46d9f4776b84d48646", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "000edb90b0c212b384a7e908fdf00259e395cd4565f66c46d9f4776b84d48646", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "000edb90b0c212b384a7e908fdf00259e395cd4565f66c46d9f4776b84d48646", kill_on_drop: false }`
[INFO] [stdout] 000edb90b0c212b384a7e908fdf00259e395cd4565f66c46d9f4776b84d48646
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+1557fb031b272b4c5bfcc7de5df7eddc7b36a584" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] bf2ee99aea0785328811f7fb5cb031cb76c2d274313aea51d41f2a40af454dd7
[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" "bf2ee99aea0785328811f7fb5cb031cb76c2d274313aea51d41f2a40af454dd7", kill_on_drop: false }`
[INFO] [stderr]     Checking either v1.5.3
[INFO] [stderr]    Compiling parity-util-mem v0.7.0
[INFO] [stderr]     Checking hash-db v0.15.2
[INFO] [stderr]     Checking libsecp256k1 v0.3.5
[INFO] [stderr]     Checking bitvec v0.17.4
[INFO] [stderr]     Checking parity-scale-codec v1.3.1
[INFO] [stderr]     Checking impl-codec v0.4.2
[INFO] [stderr]     Checking sp-wasm-interface v2.0.0-rc5
[INFO] [stderr]     Checking sp-externalities v0.8.0-rc5
[INFO] [stderr]     Checking primitive-types v0.7.2
[INFO] [stderr]     Checking sp-runtime-interface v2.0.0-rc5
[INFO] [stderr]     Checking sp-core v2.0.0-rc5
[INFO] [stderr]     Checking sp-rpc v2.0.0-rc4 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared type or module `serde_json`
[INFO] [stdout]   --> src/lib.rs:31:3
[INFO] [stdout]    |
[INFO] [stdout] 31 |         serde_json::from_str::<T>(s).unwrap(),
[INFO] [stdout]    |         ^^^^^^^^^^ use of undeclared type or module `serde_json`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared type or module `serde_json`
[INFO] [stdout]   --> src/lib.rs:35:3
[INFO] [stdout]    |
[INFO] [stdout] 35 |         serde_json::to_string(&expected).unwrap(),
[INFO] [stdout]    |         ^^^^^^^^^^ use of undeclared type or module `serde_json`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0433`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `sp-rpc`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "bf2ee99aea0785328811f7fb5cb031cb76c2d274313aea51d41f2a40af454dd7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bf2ee99aea0785328811f7fb5cb031cb76c2d274313aea51d41f2a40af454dd7", kill_on_drop: false }`
[INFO] [stdout] bf2ee99aea0785328811f7fb5cb031cb76c2d274313aea51d41f2a40af454dd7