[INFO] updating cached repository https://github.com/mknet/rust-mockall-playground
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune", kill_on_drop: false }`
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] bb88d9da5bf6b0fc293c06565fbe1c7891992071
[INFO] testing mknet/rust-mockall-playground against beta-2020-07-24 for beta-1.46-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmknet%2Frust-mockall-playground" "/workspace/builds/worker-3/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/mknet/rust-mockall-playground on toolchain beta-2020-07-24
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-07-24" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/mknet/rust-mockall-playground
[INFO] finished tweaking git repo https://github.com/mknet/rust-mockall-playground
[INFO] tweaked toml for git repo https://github.com/mknet/rust-mockall-playground written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/mknet/rust-mockall-playground already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-07-24" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-07-24" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 570307794bb52ad5a9f1fa53dd94d20c1a8942f034495c5269235a73ec0bd607
[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" "570307794bb52ad5a9f1fa53dd94d20c1a8942f034495c5269235a73ec0bd607", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "570307794bb52ad5a9f1fa53dd94d20c1a8942f034495c5269235a73ec0bd607", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "570307794bb52ad5a9f1fa53dd94d20c1a8942f034495c5269235a73ec0bd607", kill_on_drop: false }`
[INFO] [stdout] 570307794bb52ad5a9f1fa53dd94d20c1a8942f034495c5269235a73ec0bd607
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-07-24" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 94b04343d1c179ec4dbae7bf8457e246464c5d7f1c44133a5b2e3594c3a5b5e8
[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" "94b04343d1c179ec4dbae7bf8457e246464c5d7f1c44133a5b2e3594c3a5b5e8", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.33
[INFO] [stderr]    Compiling predicates-core v1.0.0
[INFO] [stderr]    Compiling difference v2.0.0
[INFO] [stderr]    Compiling normalize-line-endings v0.3.0
[INFO] [stderr]    Compiling treeline v0.1.0
[INFO] [stderr]    Compiling downcast v0.10.0
[INFO] [stderr]    Compiling fragile v1.0.0
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]    Compiling predicates-tree v1.0.0
[INFO] [stderr]    Compiling float-cmp v0.6.0
[INFO] [stderr]    Compiling predicates v1.0.4
[INFO] [stderr]    Compiling mockall_derive v0.7.1
[INFO] [stderr]    Compiling mockall v0.7.1
[INFO] [stderr]    Compiling mockall-playground v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 25.94s
[INFO] running `Command { std: "docker" "inspect" "94b04343d1c179ec4dbae7bf8457e246464c5d7f1c44133a5b2e3594c3a5b5e8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "94b04343d1c179ec4dbae7bf8457e246464c5d7f1c44133a5b2e3594c3a5b5e8", kill_on_drop: false }`
[INFO] [stdout] 94b04343d1c179ec4dbae7bf8457e246464c5d7f1c44133a5b2e3594c3a5b5e8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-07-24" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 96a20bd553fc2b64bab3d8e3c6051964d855da82477b4e62120fdbd41b6cf06e
[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" "96a20bd553fc2b64bab3d8e3c6051964d855da82477b4e62120fdbd41b6cf06e", kill_on_drop: false }`
[INFO] [stderr]    Compiling mockall-playground v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:1:19
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![cfg_attr(test, feature(proc_macro_hygiene))]
[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 `mockall-playground`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "96a20bd553fc2b64bab3d8e3c6051964d855da82477b4e62120fdbd41b6cf06e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "96a20bd553fc2b64bab3d8e3c6051964d855da82477b4e62120fdbd41b6cf06e", kill_on_drop: false }`
[INFO] [stdout] 96a20bd553fc2b64bab3d8e3c6051964d855da82477b4e62120fdbd41b6cf06e