[INFO] fetching crate compiler_builtins 0.1.39...
[INFO] checking compiler_builtins-0.1.39 against master#836c31742687ba4e2f857b5b698e1e9e6b67619c for pr-81789
[INFO] extracting crate compiler_builtins 0.1.39 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate compiler_builtins 0.1.39 on toolchain 836c31742687ba4e2f857b5b698e1e9e6b67619c
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+836c31742687ba4e2f857b5b698e1e9e6b67619c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate compiler_builtins 0.1.39
[INFO] removed 0 missing examples
[INFO] finished tweaking crates.io crate compiler_builtins 0.1.39
[INFO] tweaked toml for crates.io crate compiler_builtins 0.1.39 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] crate crates.io crate compiler_builtins 0.1.39 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+836c31742687ba4e2f857b5b698e1e9e6b67619c" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+836c31742687ba4e2f857b5b698e1e9e6b67619c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 34bb9247f07f1224203329fef0c491ee3df70c379139a4f79ceba192fb21eaee
[INFO] running `Command { std: "docker" "start" "-a" "34bb9247f07f1224203329fef0c491ee3df70c379139a4f79ceba192fb21eaee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "34bb9247f07f1224203329fef0c491ee3df70c379139a4f79ceba192fb21eaee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "34bb9247f07f1224203329fef0c491ee3df70c379139a4f79ceba192fb21eaee", kill_on_drop: false }`
[INFO] [stdout] 34bb9247f07f1224203329fef0c491ee3df70c379139a4f79ceba192fb21eaee
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+836c31742687ba4e2f857b5b698e1e9e6b67619c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 4c07eb062fb046365ac51d94085d91eaa7cc8b55a4ffc79d72895051c8fcbf35
[INFO] running `Command { std: "docker" "start" "-a" "4c07eb062fb046365ac51d94085d91eaa7cc8b55a4ffc79d72895051c8fcbf35", kill_on_drop: false }`
[INFO] [stderr]    Compiling compiler_builtins v0.1.39 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0259]: the name `core` is defined multiple times
[INFO] [stdout]   --> src/lib.rs:32:1
[INFO] [stdout]    |
[INFO] [stdout] 32 | extern crate core;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^ `core` reimported here
[INFO] [stdout]    |
[INFO] [stdout]    = note: `core` must be defined only once in the type namespace of this module
[INFO] [stdout] help: you can use `as` to change the binding name of the import
[INFO] [stdout]    |
[INFO] [stdout] 32 | extern crate core as other_core;
[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 E0259`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `compiler_builtins`
[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] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "4c07eb062fb046365ac51d94085d91eaa7cc8b55a4ffc79d72895051c8fcbf35", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4c07eb062fb046365ac51d94085d91eaa7cc8b55a4ffc79d72895051c8fcbf35", kill_on_drop: false }`
[INFO] [stdout] 4c07eb062fb046365ac51d94085d91eaa7cc8b55a4ffc79d72895051c8fcbf35