[INFO] cloning repository https://github.com/yarrow/ci-experiments-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/yarrow/ci-experiments-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fyarrow%2Fci-experiments-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fyarrow%2Fci-experiments-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ebfc983809ddcc182b7179158afecb50834cf9e6
[INFO] checking yarrow/ci-experiments-rust against master#385fa9d845dd326c6bbfd58c22244215e431948a for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fyarrow%2Fci-experiments-rust" "/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/yarrow/ci-experiments-rust on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/yarrow/ci-experiments-rust
[INFO] finished tweaking git repo https://github.com/yarrow/ci-experiments-rust
[INFO] tweaked toml for git repo https://github.com/yarrow/ci-experiments-rust written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/yarrow/ci-experiments-rust 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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]      Locking 1 package
[INFO] [stderr]     Updating ci-experiments-rust v0.1.0 (/workspace/builds/worker-4-tc1/source) -> v0.3.0
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded assert_fs v1.0.2
[INFO] [stderr]   Downloaded assert_cmd v1.0.5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d602a35f10f118de46ea39f40adfe60362f00286caccca179fbcd301c104cb09
[INFO] running `Command { std: "docker" "start" "-a" "d602a35f10f118de46ea39f40adfe60362f00286caccca179fbcd301c104cb09", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d602a35f10f118de46ea39f40adfe60362f00286caccca179fbcd301c104cb09", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d602a35f10f118de46ea39f40adfe60362f00286caccca179fbcd301c104cb09", kill_on_drop: false }`
[INFO] [stdout] d602a35f10f118de46ea39f40adfe60362f00286caccca179fbcd301c104cb09
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] abea41a3534a9d8f8039a0b4c27414c7df5cc320e0cb9066352892df80c32633
[INFO] running `Command { std: "docker" "start" "-a" "abea41a3534a9d8f8039a0b4c27414c7df5cc320e0cb9066352892df80c32633", kill_on_drop: false }`
[INFO] [stderr]    Compiling memchr v2.4.0
[INFO] [stderr]    Compiling libc v0.2.97
[INFO] [stderr]     Checking regex-syntax v0.6.25
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]     Checking regex-automata v0.1.10
[INFO] [stderr]    Compiling crossbeam-utils v0.8.5
[INFO] [stderr]    Compiling doc-comment v0.3.3
[INFO] [stderr]     Checking once_cell v1.8.0
[INFO] [stderr]     Checking predicates-core v1.0.2
[INFO] [stderr]     Checking normalize-line-endings v0.3.0
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]     Checking walkdir v2.3.2
[INFO] [stderr]     Checking difference v2.0.0
[INFO] [stderr]     Checking treeline v0.1.0
[INFO] [stderr]     Checking ci-experiments-rust v0.3.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking predicates-tree v1.0.2
[INFO] [stderr]     Checking thread_local v1.1.3
[INFO] [stderr]     Checking getrandom v0.2.3
[INFO] [stderr]     Checking wait-timeout v0.2.0
[INFO] [stderr]     Checking aho-corasick v0.7.18
[INFO] [stderr]     Checking bstr v0.2.16
[INFO] [stderr]     Checking rand_core v0.6.3
[INFO] [stderr]     Checking float-cmp v0.8.0
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking rand v0.8.4
[INFO] [stderr]     Checking regex v1.5.4
[INFO] [stderr]     Checking tempfile v3.2.0
[INFO] [stderr]     Checking globset v0.4.8
[INFO] [stderr]     Checking predicates v1.0.8
[INFO] [stderr]     Checking ignore v0.4.18
[INFO] [stderr]     Checking assert_cmd v1.0.5
[INFO] [stderr]     Checking globwalk v0.8.1
[INFO] [stderr]     Checking assert_fs v1.0.2
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.35s
[INFO] running `Command { std: "docker" "inspect" "abea41a3534a9d8f8039a0b4c27414c7df5cc320e0cb9066352892df80c32633", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "abea41a3534a9d8f8039a0b4c27414c7df5cc320e0cb9066352892df80c32633", kill_on_drop: false }`
[INFO] [stdout] abea41a3534a9d8f8039a0b4c27414c7df5cc320e0cb9066352892df80c32633
[INFO] checking yarrow/ci-experiments-rust against try#645bb72776a6a56a1a8f52631a44bd082b2ba509 for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fyarrow%2Fci-experiments-rust" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/yarrow/ci-experiments-rust on toolchain 645bb72776a6a56a1a8f52631a44bd082b2ba509
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/yarrow/ci-experiments-rust
[INFO] finished tweaking git repo https://github.com/yarrow/ci-experiments-rust
[INFO] tweaked toml for git repo https://github.com/yarrow/ci-experiments-rust written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/yarrow/ci-experiments-rust 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" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] aced5d505e3d531005f91a59bcd48cd633220a3eb2a1e66602d9a3552ece77d7
[INFO] running `Command { std: "docker" "start" "-a" "aced5d505e3d531005f91a59bcd48cd633220a3eb2a1e66602d9a3552ece77d7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "aced5d505e3d531005f91a59bcd48cd633220a3eb2a1e66602d9a3552ece77d7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "aced5d505e3d531005f91a59bcd48cd633220a3eb2a1e66602d9a3552ece77d7", kill_on_drop: false }`
[INFO] [stdout] aced5d505e3d531005f91a59bcd48cd633220a3eb2a1e66602d9a3552ece77d7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 82f33878ff46b4aa8c543c552a489781f6fa0fbab45352bcbd660b1cd4e71abb
[INFO] running `Command { std: "docker" "start" "-a" "82f33878ff46b4aa8c543c552a489781f6fa0fbab45352bcbd660b1cd4e71abb", kill_on_drop: false }`
[INFO] [stderr]    Compiling memchr v2.4.0
[INFO] [stderr]    Compiling libc v0.2.97
[INFO] [stderr]     Checking regex-syntax v0.6.25
[INFO] [stderr]     Checking regex-automata v0.1.10
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]    Compiling crossbeam-utils v0.8.5
[INFO] [stderr]     Checking predicates-core v1.0.2
[INFO] [stderr]     Checking once_cell v1.8.0
[INFO] [stderr]    Compiling doc-comment v0.3.3
[INFO] [stderr]     Checking difference v2.0.0
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]     Checking walkdir v2.3.2
[INFO] [stderr]     Checking normalize-line-endings v0.3.0
[INFO] [stderr]     Checking treeline v0.1.0
[INFO] [stderr]     Checking ci-experiments-rust v0.3.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking thread_local v1.1.3
[INFO] [stderr]     Checking predicates-tree v1.0.2
[INFO] [stderr]     Checking aho-corasick v0.7.18
[INFO] [stderr]     Checking bstr v0.2.16
[INFO] [stderr]     Checking getrandom v0.2.3
[INFO] [stderr]     Checking wait-timeout v0.2.0
[INFO] [stderr]     Checking rand_core v0.6.3
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking float-cmp v0.8.0
[INFO] [stderr]     Checking rand v0.8.4
[INFO] [stderr]     Checking regex v1.5.4
[INFO] [stderr]     Checking tempfile v3.2.0
[INFO] [stderr]     Checking globset v0.4.8
[INFO] [stderr]     Checking predicates v1.0.8
[INFO] [stderr]     Checking assert_cmd v1.0.5
[INFO] [stderr]     Checking ignore v0.4.18
[INFO] [stderr]     Checking globwalk v0.8.1
[INFO] [stderr]     Checking assert_fs v1.0.2
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 5.97s
[INFO] running `Command { std: "docker" "inspect" "82f33878ff46b4aa8c543c552a489781f6fa0fbab45352bcbd660b1cd4e71abb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "82f33878ff46b4aa8c543c552a489781f6fa0fbab45352bcbd660b1cd4e71abb", kill_on_drop: false }`
[INFO] [stdout] 82f33878ff46b4aa8c543c552a489781f6fa0fbab45352bcbd660b1cd4e71abb