[INFO] fetching crate sp-rpc 2.0.0-alpha.6...
[INFO] testing sp-rpc-2.0.0-alpha.6 against try#41997647ba6a77908f6ef64401414feb00bccf16 for pr-71274
[INFO] extracting crate sp-rpc 2.0.0-alpha.6 into /workspace/builds/worker-1/source
[INFO] validating manifest of crates.io crate sp-rpc 2.0.0-alpha.6 on toolchain 41997647ba6a77908f6ef64401414feb00bccf16
[INFO] running `"/workspace/cargo-home/bin/cargo" "+41997647ba6a77908f6ef64401414feb00bccf16" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate sp-rpc 2.0.0-alpha.6
[INFO] finished tweaking crates.io crate sp-rpc 2.0.0-alpha.6
[INFO] tweaked toml for crates.io crate sp-rpc 2.0.0-alpha.6 written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+41997647ba6a77908f6ef64401414feb00bccf16" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+41997647ba6a77908f6ef64401414feb00bccf16" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "/opt/rustwide/cargo-home/bin/cargo" "+41997647ba6a77908f6ef64401414feb00bccf16" "build" "--frozen"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 08906ed6b6c293428ccae65830dbf0018f015f4a91cd62632d6aeb1bbc400fc3
[INFO] running `"docker" "start" "-a" "08906ed6b6c293428ccae65830dbf0018f015f4a91cd62632d6aeb1bbc400fc3"`
[INFO] [stderr]    Compiling parity-util-mem v0.6.1
[INFO] [stderr]    Compiling hash-db v0.15.2
[INFO] [stderr]    Compiling parity-scale-codec v1.3.0
[INFO] [stderr]    Compiling impl-codec v0.4.2
[INFO] [stderr]    Compiling sp-wasm-interface v2.0.0-alpha.6
[INFO] [stderr]    Compiling primitive-types v0.7.0
[INFO] [stderr]    Compiling sp-runtime-interface v2.0.0-alpha.6
[INFO] [stderr]    Compiling sp-core v2.0.0-alpha.6
[INFO] [stderr]    Compiling sp-rpc v2.0.0-alpha.6 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 28.67s
[INFO] running `"docker" "inspect" "08906ed6b6c293428ccae65830dbf0018f015f4a91cd62632d6aeb1bbc400fc3"`
[INFO] running `"docker" "rm" "-f" "08906ed6b6c293428ccae65830dbf0018f015f4a91cd62632d6aeb1bbc400fc3"`
[INFO] [stdout] 08906ed6b6c293428ccae65830dbf0018f015f4a91cd62632d6aeb1bbc400fc3
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "/opt/rustwide/cargo-home/bin/cargo" "+41997647ba6a77908f6ef64401414feb00bccf16" "test" "--frozen" "--no-run"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] c97c6009e42d30aee3abafb32b25cfb36bf6b48df335d2d7728d46c844148aa9
[INFO] running `"docker" "start" "-a" "c97c6009e42d30aee3abafb32b25cfb36bf6b48df335d2d7728d46c844148aa9"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling sp-rpc v2.0.0-alpha.6 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0433]: failed to resolve: use of undeclared type or module `serde_json`
[INFO] [stderr]   --> src/lib.rs:30:3
[INFO] [stderr]    |
[INFO] [stderr] 30 |         serde_json::from_str::<T>(s).unwrap(),
[INFO] [stderr]    |         ^^^^^^^^^^ use of undeclared type or module `serde_json`
[INFO] [stderr] 
[INFO] [stderr] error[E0433]: failed to resolve: use of undeclared type or module `serde_json`
[INFO] [stderr]   --> src/lib.rs:34:3
[INFO] [stderr]    |
[INFO] [stderr] 34 |         serde_json::to_string(&expected).unwrap(),
[INFO] [stderr]    |         ^^^^^^^^^^ use of undeclared type or module `serde_json`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 2 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0433`.
[INFO] [stderr] error: could not compile `sp-rpc`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "c97c6009e42d30aee3abafb32b25cfb36bf6b48df335d2d7728d46c844148aa9"`
[INFO] running `"docker" "rm" "-f" "c97c6009e42d30aee3abafb32b25cfb36bf6b48df335d2d7728d46c844148aa9"`
[INFO] [stdout] c97c6009e42d30aee3abafb32b25cfb36bf6b48df335d2d7728d46c844148aa9