[INFO] fetching crate nibbler 0.2.3...
[INFO] checking nibbler-0.2.3 against master#36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923 for pr-81863
[INFO] extracting crate nibbler 0.2.3 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate nibbler 0.2.3 on toolchain 36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate nibbler 0.2.3
[INFO] finished tweaking crates.io crate nibbler 0.2.3
[INFO] tweaked toml for crates.io crate nibbler 0.2.3 written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f4cfde073d1bad3cbf98f178be7a8a344453733772f7a1c931f4e41a7a94233e
[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" "f4cfde073d1bad3cbf98f178be7a8a344453733772f7a1c931f4e41a7a94233e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f4cfde073d1bad3cbf98f178be7a8a344453733772f7a1c931f4e41a7a94233e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f4cfde073d1bad3cbf98f178be7a8a344453733772f7a1c931f4e41a7a94233e", kill_on_drop: false }`
[INFO] [stdout] f4cfde073d1bad3cbf98f178be7a8a344453733772f7a1c931f4e41a7a94233e
[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=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" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 82197cd7167197e017b51fff631a02bd873105dbdb835ab3965045b54d348fe4
[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" "82197cd7167197e017b51fff631a02bd873105dbdb835ab3965045b54d348fe4", kill_on_drop: false }`
[INFO] [stderr]     Checking nibbler v0.2.3 (/opt/rustwide/workdir)
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]    --> src/nibble.rs:385:25
[INFO] [stdout]     |
[INFO] [stdout] 385 |             _ => panic!(format!("invalid hex-dec character: `{}`", c)),
[INFO] [stdout]     |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(non_fmt_panic)]` on by default
[INFO] [stdout]     = note: this is no longer accepted in Rust 2021
[INFO] [stdout]     = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]    --> src/nibbles.rs:171:38
[INFO] [stdout]     |
[INFO] [stdout] 171 |         assert!(s.starts_with("0x"), format!("Hex-dec string {} did not start with `0x`", s));
[INFO] [stdout]     |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this is no longer accepted in Rust 2021
[INFO] [stdout]     = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]    --> src/nibble.rs:385:25
[INFO] [stdout]     |
[INFO] [stdout] 385 |             _ => panic!(format!("invalid hex-dec character: `{}`", c)),
[INFO] [stdout]     |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(non_fmt_panic)]` on by default
[INFO] [stdout]     = note: this is no longer accepted in Rust 2021
[INFO] [stdout]     = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]    --> src/nibbles.rs:171:38
[INFO] [stdout]     |
[INFO] [stdout] 171 |         assert!(s.starts_with("0x"), format!("Hex-dec string {} did not start with `0x`", s));
[INFO] [stdout]     |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this is no longer accepted in Rust 2021
[INFO] [stdout]     = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.12s
[INFO] running `Command { std: "docker" "inspect" "82197cd7167197e017b51fff631a02bd873105dbdb835ab3965045b54d348fe4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "82197cd7167197e017b51fff631a02bd873105dbdb835ab3965045b54d348fe4", kill_on_drop: false }`
[INFO] [stdout] 82197cd7167197e017b51fff631a02bd873105dbdb835ab3965045b54d348fe4