[INFO] cloning repository https://github.com/pLesur/serde_slim
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/pLesur/serde_slim" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FpLesur%2Fserde_slim", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FpLesur%2Fserde_slim'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 29d809a58494f4d9286112074392f77f50e3c7d3
[INFO] testing pLesur/serde_slim against beta-2021-09-08 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FpLesur%2Fserde_slim" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/pLesur/serde_slim on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/pLesur/serde_slim
[INFO] finished tweaking git repo https://github.com/pLesur/serde_slim
[INFO] tweaked toml for git repo https://github.com/pLesur/serde_slim written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/pLesur/serde_slim already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4ac1aab1b9cde3aa5fc8f8a2fb932d8e904eb70aee5b3763f5076ad8cbfe72a8
[INFO] running `Command { std: "docker" "start" "-a" "4ac1aab1b9cde3aa5fc8f8a2fb932d8e904eb70aee5b3763f5076ad8cbfe72a8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4ac1aab1b9cde3aa5fc8f8a2fb932d8e904eb70aee5b3763f5076ad8cbfe72a8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4ac1aab1b9cde3aa5fc8f8a2fb932d8e904eb70aee5b3763f5076ad8cbfe72a8", kill_on_drop: false }`
[INFO] [stdout] 4ac1aab1b9cde3aa5fc8f8a2fb932d8e904eb70aee5b3763f5076ad8cbfe72a8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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=warn" "-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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a070abbdc62ba47feb3f66fd13b64edd98b323c149b979ad0ecdfcf7a2a7ac39
[INFO] running `Command { std: "docker" "start" "-a" "a070abbdc62ba47feb3f66fd13b64edd98b323c149b979ad0ecdfcf7a2a7ac39", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v0.15.42
[INFO] [stderr]    Compiling serde_slim v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 11.61s
[INFO] running `Command { std: "docker" "inspect" "a070abbdc62ba47feb3f66fd13b64edd98b323c149b979ad0ecdfcf7a2a7ac39", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a070abbdc62ba47feb3f66fd13b64edd98b323c149b979ad0ecdfcf7a2a7ac39", kill_on_drop: false }`
[INFO] [stdout] a070abbdc62ba47feb3f66fd13b64edd98b323c149b979ad0ecdfcf7a2a7ac39
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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=warn" "-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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f538d6eb33228513ac77f55f66dcb836bdf064aedd74c30c739ff238371f6549
[INFO] running `Command { std: "docker" "start" "-a" "f538d6eb33228513ac77f55f66dcb836bdf064aedd74c30c739ff238371f6549", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde_slim v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> tests/basic.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(custom_attribute)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: removed in favor of `#![register_tool]` and `#![register_attr]`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot find attribute `serde` in this scope
[INFO] [stdout]  --> tests/basic.rs:9:11
[INFO] [stdout]   |
[INFO] [stdout] 9 |         #[serde(skip_serializing)]
[INFO] [stdout]   |           ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> tests/basic.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(custom_attribute)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0557.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `serde_slim` due to 4 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "f538d6eb33228513ac77f55f66dcb836bdf064aedd74c30c739ff238371f6549", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f538d6eb33228513ac77f55f66dcb836bdf064aedd74c30c739ff238371f6549", kill_on_drop: false }`
[INFO] [stdout] f538d6eb33228513ac77f55f66dcb836bdf064aedd74c30c739ff238371f6549