[INFO] fetching crate dm_x 0.2.3...
[INFO] checking dm_x-0.2.3 against 1.95.0 for pr-155915
[INFO] extracting crate dm_x 0.2.3 into /workspace/builds/worker-2-tc1/source
[INFO] started tweaking crates.io crate dm_x 0.2.3
[INFO] finished tweaking crates.io crate dm_x 0.2.3
[INFO] tweaked toml for crates.io crate dm_x 0.2.3 written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate dm_x 0.2.3 on toolchain 1.95.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.95.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate dm_x 0.2.3 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.95.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] fb67777eb20f9862bf06a2e5b7d00b2a3db340220fb15fd31965c712f6067fcb
[INFO] running `Command { std: "docker" "start" "-a" "fb67777eb20f9862bf06a2e5b7d00b2a3db340220fb15fd31965c712f6067fcb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "fb67777eb20f9862bf06a2e5b7d00b2a3db340220fb15fd31965c712f6067fcb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fb67777eb20f9862bf06a2e5b7d00b2a3db340220fb15fd31965c712f6067fcb", kill_on_drop: false }`
[INFO] [stdout] fb67777eb20f9862bf06a2e5b7d00b2a3db340220fb15fd31965c712f6067fcb
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/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" "RUSTDOCFLAGS=--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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9013d7f20d9081a88e56e02403116556d0c1c6b1e2fce8455e530c8d8de90751
[INFO] running `Command { std: "docker" "start" "-a" "9013d7f20d9081a88e56e02403116556d0c1c6b1e2fce8455e530c8d8de90751", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.39
[INFO] [stderr]    Compiling unicode-ident v1.0.0
[INFO] [stderr]    Compiling syn v1.0.96
[INFO] [stderr]    Compiling serde_derive v1.0.137
[INFO] [stderr]    Compiling serde v1.0.137
[INFO] [stderr]    Compiling serde_json v1.0.81
[INFO] [stderr]     Checking once_cell v1.12.0
[INFO] [stderr]     Checking dm_x v0.2.3 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:97:1
[INFO] [stdout]    |
[INFO] [stdout] 97 | #![feature(doc_cfg)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `dm_x` (lib) due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "9013d7f20d9081a88e56e02403116556d0c1c6b1e2fce8455e530c8d8de90751", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9013d7f20d9081a88e56e02403116556d0c1c6b1e2fce8455e530c8d8de90751", kill_on_drop: false }`
[INFO] [stdout] 9013d7f20d9081a88e56e02403116556d0c1c6b1e2fce8455e530c8d8de90751
