[INFO] cloning repository https://github.com/murasakiwano/mandelbrot
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/murasakiwano/mandelbrot" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmurasakiwano%2Fmandelbrot", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmurasakiwano%2Fmandelbrot'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 02af0f5ea47d08c07534e9ad07a7e2fbc7b9dcb1
[INFO] checking murasakiwano/mandelbrot against master#d93f678fa55842cccd2f091deccd93e9494b3764 for pr-138844
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmurasakiwano%2Fmandelbrot" "/workspace/builds/worker-6-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/murasakiwano/mandelbrot on toolchain d93f678fa55842cccd2f091deccd93e9494b3764
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+d93f678fa55842cccd2f091deccd93e9494b3764" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/murasakiwano/mandelbrot
[INFO] finished tweaking git repo https://github.com/murasakiwano/mandelbrot
[INFO] tweaked toml for git repo https://github.com/murasakiwano/mandelbrot written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/murasakiwano/mandelbrot 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" "+d93f678fa55842cccd2f091deccd93e9494b3764" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:4b26683ee3c49f365255c425c23003cbf4366de097804722c29c5bbbee3624d2" "/opt/rustwide/cargo-home/bin/cargo" "+d93f678fa55842cccd2f091deccd93e9494b3764" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f9a27f834844d0fb1206dca5c81ccc4eecc15a27a802d5cb81d646c070a97d7a
[INFO] running `Command { std: "docker" "start" "-a" "f9a27f834844d0fb1206dca5c81ccc4eecc15a27a802d5cb81d646c070a97d7a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f9a27f834844d0fb1206dca5c81ccc4eecc15a27a802d5cb81d646c070a97d7a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f9a27f834844d0fb1206dca5c81ccc4eecc15a27a802d5cb81d646c070a97d7a", kill_on_drop: false }`
[INFO] [stdout] f9a27f834844d0fb1206dca5c81ccc4eecc15a27a802d5cb81d646c070a97d7a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/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" "RUSTDOCFLAGS=--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:4b26683ee3c49f365255c425c23003cbf4366de097804722c29c5bbbee3624d2" "/opt/rustwide/cargo-home/bin/cargo" "+d93f678fa55842cccd2f091deccd93e9494b3764" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] fc9ec32c40e77405356891e45b95ec2e271c1c7cd847922c4c82c7e5b85ac8aa
[INFO] running `Command { std: "docker" "start" "-a" "fc9ec32c40e77405356891e45b95ec2e271c1c7cd847922c4c82c7e5b85ac8aa", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]    Compiling crossbeam-utils v0.8.15
[INFO] [stderr]    Compiling libc v0.2.142
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]    Compiling proc-macro2 v1.0.56
[INFO] [stderr]    Compiling unicode-ident v1.0.8
[INFO] [stderr]    Compiling quote v1.0.26
[INFO] [stderr]     Checking adler v1.0.2
[INFO] [stderr]    Compiling rayon-core v1.11.0
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]     Checking simd-adler32 v0.3.5
[INFO] [stderr]    Compiling crc32fast v1.3.2
[INFO] [stderr]     Checking miniz_oxide v0.6.2
[INFO] [stderr]    Compiling futures-core v0.3.28
[INFO] [stderr]     Checking either v1.8.1
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/proc-macro2-1.0.56/src/lib.rs:92:30
[INFO] [stdout]    |
[INFO] [stdout] 92 |     feature(proc_macro_span, proc_macro_span_shrink)
[INFO] [stdout]    |                              ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling memoffset v0.8.0
[INFO] [stdout] For more information about this error, try `rustc --explain E0635`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `proc-macro2` (lib) due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "fc9ec32c40e77405356891e45b95ec2e271c1c7cd847922c4c82c7e5b85ac8aa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fc9ec32c40e77405356891e45b95ec2e271c1c7cd847922c4c82c7e5b85ac8aa", kill_on_drop: false }`
[INFO] [stdout] fc9ec32c40e77405356891e45b95ec2e271c1c7cd847922c4c82c7e5b85ac8aa