[INFO] fetching crate mcs 0.1.1...
[INFO] testing mcs-0.1.1 against 1.49.0 for beta-1.50-1
[INFO] extracting crate mcs 0.1.1 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate mcs 0.1.1 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 crates.io crate mcs 0.1.1
[INFO] finished tweaking crates.io crate mcs 0.1.1
[INFO] tweaked toml for crates.io crate mcs 0.1.1 written to /workspace/builds/worker-7/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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] b9579eca4757add8c6d10e11dd9a97ffedb09f7e957a1c11a5693d52a19423b8
[INFO] running `Command { std: "docker" "start" "-a" "b9579eca4757add8c6d10e11dd9a97ffedb09f7e957a1c11a5693d52a19423b8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b9579eca4757add8c6d10e11dd9a97ffedb09f7e957a1c11a5693d52a19423b8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b9579eca4757add8c6d10e11dd9a97ffedb09f7e957a1c11a5693d52a19423b8", kill_on_drop: false }`
[INFO] [stdout] b9579eca4757add8c6d10e11dd9a97ffedb09f7e957a1c11a5693d52a19423b8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] f6d6b936f2d2f7f87bdd5b764fda137950b60183a619fdb63ca347faa64619d9
[INFO] running `Command { std: "docker" "start" "-a" "f6d6b936f2d2f7f87bdd5b764fda137950b60183a619fdb63ca347faa64619d9", kill_on_drop: false }`
[INFO] [stderr]    Compiling mcs v0.1.1 (/opt/rustwide/workdir)
[INFO] [stdout] error: the legacy LLVM-style asm! syntax is no longer supported
[INFO] [stdout]  --> src/pause.rs:6:14
[INFO] [stdout]   |
[INFO] [stdout] 6 |     unsafe { asm!("pause" :::: "volatile"); }
[INFO] [stdout]   |              ----^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |              |
[INFO] [stdout]   |              help: replace with: `llvm_asm!`
[INFO] [stdout]   |
[INFO] [stdout]   = note: consider migrating to the new asm! syntax specified in RFC 2873
[INFO] [stdout]   = note: alternatively, switch to llvm_asm! to keep your code working as it is
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:35
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![cfg_attr(feature = "unstable", feature(asm, const_fn, generic_param_attrs, dropck_eyepatch))]
[INFO] [stdout]   |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `mcs`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "f6d6b936f2d2f7f87bdd5b764fda137950b60183a619fdb63ca347faa64619d9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f6d6b936f2d2f7f87bdd5b764fda137950b60183a619fdb63ca347faa64619d9", kill_on_drop: false }`
[INFO] [stdout] f6d6b936f2d2f7f87bdd5b764fda137950b60183a619fdb63ca347faa64619d9