[INFO] fetching crate ptah 0.1.0...
[INFO] testing ptah-0.1.0 against 1.49.0 for beta-1.50-1
[INFO] extracting crate ptah 0.1.0 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate ptah 0.1.0 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 ptah 0.1.0
[INFO] finished tweaking crates.io crate ptah 0.1.0
[INFO] tweaked toml for crates.io crate ptah 0.1.0 written to /workspace/builds/worker-5/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-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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] 3646d0d58dd6a140a00e10683dbe58095dedeaeea4833d9133c8fcb33a46f230
[INFO] running `Command { std: "docker" "start" "-a" "3646d0d58dd6a140a00e10683dbe58095dedeaeea4833d9133c8fcb33a46f230", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3646d0d58dd6a140a00e10683dbe58095dedeaeea4833d9133c8fcb33a46f230", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3646d0d58dd6a140a00e10683dbe58095dedeaeea4833d9133c8fcb33a46f230", kill_on_drop: false }`
[INFO] [stdout] 3646d0d58dd6a140a00e10683dbe58095dedeaeea4833d9133c8fcb33a46f230
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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] 4f40325d676a1c1fca294466bfa1c3ced3ba39dde7a32c42122357b40aa3c0c0
[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" "4f40325d676a1c1fca294466bfa1c3ced3ba39dde7a32c42122357b40aa3c0c0", kill_on_drop: false }`
[INFO] [stderr]    Compiling ptah_derive v0.1.0
[INFO] [stderr]    Compiling ptah v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | / #![feature(
[INFO] [stdout] 3 | |     const_generics,
[INFO] [stdout] 4 | |     assoc_char_funcs,
[INFO] [stdout] 5 | |     decl_macro,
[INFO] [stdout] ... |
[INFO] [stdout] 8 | |     never_type
[INFO] [stdout] 9 | | )]
[INFO] [stdout]   | |__^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `const_generics` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]  --> src/lib.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 |     const_generics,
[INFO] [stdout]   |     ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]   = note: see issue #44580 <https://github.com/rust-lang/rust/issues/44580> for more information
[INFO] [stdout]   = help: consider using `min_const_generics` instead, which is more stable and complete
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `#[macro_use]` import
[INFO] [stdout]   --> src/lib.rs:14:1
[INFO] [stdout]    |
[INFO] [stdout] 14 | #[macro_use]
[INFO] [stdout]    | ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `ptah`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "4f40325d676a1c1fca294466bfa1c3ced3ba39dde7a32c42122357b40aa3c0c0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4f40325d676a1c1fca294466bfa1c3ced3ba39dde7a32c42122357b40aa3c0c0", kill_on_drop: false }`
[INFO] [stdout] 4f40325d676a1c1fca294466bfa1c3ced3ba39dde7a32c42122357b40aa3c0c0