[INFO] cloning repository https://github.com/SE-691-Graphing-Calculator/esoteric_nonsense
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/SE-691-Graphing-Calculator/esoteric_nonsense" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSE-691-Graphing-Calculator%2Fesoteric_nonsense", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSE-691-Graphing-Calculator%2Fesoteric_nonsense'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 2baf86fbe7875e1dfb6cea74142ae1b32f47a1dd
[INFO] testing SE-691-Graphing-Calculator/esoteric_nonsense against 1.49.0 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSE-691-Graphing-Calculator%2Fesoteric_nonsense" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/SE-691-Graphing-Calculator/esoteric_nonsense on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/SE-691-Graphing-Calculator/esoteric_nonsense
[INFO] finished tweaking git repo https://github.com/SE-691-Graphing-Calculator/esoteric_nonsense
[INFO] tweaked toml for git repo https://github.com/SE-691-Graphing-Calculator/esoteric_nonsense written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: file found to be present in multiple build targets: /workspace/builds/worker-4/source/src/main.rs
[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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1e75f96ac26a8800e56c394003ce37f3d2ea5738b29abf814b276219f42d005d
[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" "1e75f96ac26a8800e56c394003ce37f3d2ea5738b29abf814b276219f42d005d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1e75f96ac26a8800e56c394003ce37f3d2ea5738b29abf814b276219f42d005d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1e75f96ac26a8800e56c394003ce37f3d2ea5738b29abf814b276219f42d005d", kill_on_drop: false }`
[INFO] [stdout] 1e75f96ac26a8800e56c394003ce37f3d2ea5738b29abf814b276219f42d005d
[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=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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c20ed9bba51c2c60f51c438ce219dce79ac9cd10aa127e0f8323cbebe56304c6
[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" "c20ed9bba51c2c60f51c438ce219dce79ac9cd10aa127e0f8323cbebe56304c6", kill_on_drop: false }`
[INFO] [stderr] warning: file found to be present in multiple build targets: /opt/rustwide/workdir/src/main.rs
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling pyo3 v0.11.1
[INFO] [stderr]    Compiling quote v1.0.8
[INFO] [stderr]    Compiling inline-python-macros v0.5.3
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/inline-python-macros-0.5.3/src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(proc_macro_span)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[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 E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `inline-python-macros`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "c20ed9bba51c2c60f51c438ce219dce79ac9cd10aa127e0f8323cbebe56304c6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c20ed9bba51c2c60f51c438ce219dce79ac9cd10aa127e0f8323cbebe56304c6", kill_on_drop: false }`
[INFO] [stdout] c20ed9bba51c2c60f51c438ce219dce79ac9cd10aa127e0f8323cbebe56304c6