[INFO] cloning repository https://github.com/iyappan04/rust-blockchain
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/iyappan04/rust-blockchain" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fiyappan04%2Frust-blockchain", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fiyappan04%2Frust-blockchain'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a5e182b4b02c4ca72a194886244b164301827d61
[INFO] checking iyappan04/rust-blockchain against master#f00b02e6bbe63707503f058fb87cc3e2b25991ac for pr-125596
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fiyappan04%2Frust-blockchain" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/iyappan04/rust-blockchain on toolchain f00b02e6bbe63707503f058fb87cc3e2b25991ac
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+f00b02e6bbe63707503f058fb87cc3e2b25991ac" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/iyappan04/rust-blockchain
[INFO] finished tweaking git repo https://github.com/iyappan04/rust-blockchain
[INFO] tweaked toml for git repo https://github.com/iyappan04/rust-blockchain written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/iyappan04/rust-blockchain 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" "+f00b02e6bbe63707503f058fb87cc3e2b25991ac" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr] error: failed to select a version for `libp2p`.
[INFO] [stderr]     ... required by package `rust-blockchain v0.1.0 (/workspace/builds/worker-4-tc1/source)`
[INFO] [stderr] versions that meet the requirements `^0.53.2` are: 0.53.2
[INFO] [stderr] 
[INFO] [stderr] the package `rust-blockchain` depends on `libp2p`, with features: `tcp-tokio` but `libp2p` does not have these features.
[INFO] [stderr] 
[INFO] [stderr] 
[INFO] [stderr] failed to select a version for `libp2p` which could resolve this conflict
[ERROR] this task or one of its parent failed!
[ERROR] command failed: exit status: 101
[ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace.