[INFO] cloning repository https://github.com/FUTingFei/programming_bitcoin_rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/FUTingFei/programming_bitcoin_rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FFUTingFei%2Fprogramming_bitcoin_rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FFUTingFei%2Fprogramming_bitcoin_rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] d6a9bdb48fc565e6491668f97899be7ae1e3bacb
[INFO] checking FUTingFei/programming_bitcoin_rust against try#9cfe725f0995b018340c519db1b2f3cf8a7e0631 for pr-81174
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FFUTingFei%2Fprogramming_bitcoin_rust" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/FUTingFei/programming_bitcoin_rust on toolchain 9cfe725f0995b018340c519db1b2f3cf8a7e0631
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9cfe725f0995b018340c519db1b2f3cf8a7e0631" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/FUTingFei/programming_bitcoin_rust
[INFO] finished tweaking git repo https://github.com/FUTingFei/programming_bitcoin_rust
[INFO] tweaked toml for git repo https://github.com/FUTingFei/programming_bitcoin_rust written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/FUTingFei/programming_bitcoin_rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9cfe725f0995b018340c519db1b2f3cf8a7e0631" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+9cfe725f0995b018340c519db1b2f3cf8a7e0631" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1766d14c5c2866db4bf46d82c40cb2d45042ac14808501f53dc528bf79a5da62
[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" "1766d14c5c2866db4bf46d82c40cb2d45042ac14808501f53dc528bf79a5da62", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1766d14c5c2866db4bf46d82c40cb2d45042ac14808501f53dc528bf79a5da62", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1766d14c5c2866db4bf46d82c40cb2d45042ac14808501f53dc528bf79a5da62", kill_on_drop: false }`
[INFO] [stdout] 1766d14c5c2866db4bf46d82c40cb2d45042ac14808501f53dc528bf79a5da62
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "rustops/crates-build-env@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+9cfe725f0995b018340c519db1b2f3cf8a7e0631" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 68290e1c7ee1c765e8b14569e26b69fd7fdfb08fb335b6211e75195a9cce7f23
[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" "68290e1c7ee1c765e8b14569e26b69fd7fdfb08fb335b6211e75195a9cce7f23", kill_on_drop: false }`
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]    Compiling num-bigint v0.3.0
[INFO] [stderr]     Checking num-integer v0.1.43
[INFO] [stderr]     Checking programming_bitcoin_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0635]: unknown feature `const_int_pow`
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(const_int_pow)]
[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 E0635`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `programming_bitcoin_rust`
[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] [stdout] error[E0635]: unknown feature `const_int_pow`
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(const_int_pow)]
[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 E0635`.
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "68290e1c7ee1c765e8b14569e26b69fd7fdfb08fb335b6211e75195a9cce7f23", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "68290e1c7ee1c765e8b14569e26b69fd7fdfb08fb335b6211e75195a9cce7f23", kill_on_drop: false }`
[INFO] [stdout] 68290e1c7ee1c765e8b14569e26b69fd7fdfb08fb335b6211e75195a9cce7f23