[INFO] fetching crate combomatic 0.0.0...
[INFO] testing combomatic-0.0.0 against master#160e7623e8cbbf1feab2b6e2a24733a98c7bde9c for pr-145628
[INFO] extracting crate combomatic 0.0.0 into /workspace/builds/worker-6-tc1/source
[INFO] started tweaking crates.io crate combomatic 0.0.0
[INFO] finished tweaking crates.io crate combomatic 0.0.0
[INFO] tweaked toml for crates.io crate combomatic 0.0.0 written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate combomatic 0.0.0 on toolchain 160e7623e8cbbf1feab2b6e2a24733a98c7bde9c
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+160e7623e8cbbf1feab2b6e2a24733a98c7bde9c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+160e7623e8cbbf1feab2b6e2a24733a98c7bde9c" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 21 packages to latest compatible versions
[INFO] [stderr]       Adding structopt v0.2.18 (available: v0.3.26)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+160e7623e8cbbf1feab2b6e2a24733a98c7bde9c" "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@sha256:7ad1b28ee6f5f7f699f6cf7015098d6ccdd96d6f2d78dd06228f5b4c9faf309c" "/opt/rustwide/cargo-home/bin/cargo" "+160e7623e8cbbf1feab2b6e2a24733a98c7bde9c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] db5a990669c633014ea4a10082e9ab868565365240d88db912438cfc6c69f011
[INFO] running `Command { std: "docker" "start" "-a" "db5a990669c633014ea4a10082e9ab868565365240d88db912438cfc6c69f011", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "db5a990669c633014ea4a10082e9ab868565365240d88db912438cfc6c69f011", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "db5a990669c633014ea4a10082e9ab868565365240d88db912438cfc6c69f011", kill_on_drop: false }`
[INFO] [stdout] db5a990669c633014ea4a10082e9ab868565365240d88db912438cfc6c69f011
[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@sha256:7ad1b28ee6f5f7f699f6cf7015098d6ccdd96d6f2d78dd06228f5b4c9faf309c" "/opt/rustwide/cargo-home/bin/cargo" "+160e7623e8cbbf1feab2b6e2a24733a98c7bde9c" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e525acf3a43c33a2dc79f9a1a9e51a50f1cadc9c8f8f6e6f6243ac763916f1f8
[INFO] running `Command { std: "docker" "start" "-a" "e525acf3a43c33a2dc79f9a1a9e51a50f1cadc9c8f8f6e6f6243ac763916f1f8", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling libc v0.2.175
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling unicode-width v0.1.14
[INFO] [stderr]    Compiling unicode-segmentation v1.12.0
[INFO] [stderr]    Compiling strsim v0.8.0
[INFO] [stderr]    Compiling ansi_term v0.12.1
[INFO] [stderr]    Compiling bitflags v1.3.2
[INFO] [stderr]    Compiling textwrap v0.11.0
[INFO] [stderr]    Compiling vec_map v0.8.2
[INFO] [stderr]    Compiling heck v0.3.3
[INFO] [stderr] error: could not compile `heck` (lib)
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   could not execute process `/opt/rustwide/rustup-home/toolchains/160e7623e8cbbf1feab2b6e2a24733a98c7bde9c/bin/rustc --crate-name heck --edition=2018 /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/heck-0.3.3/src/lib.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --crate-type lib --emit=dep-info,metadata,link -C embed-bitcode=no --check-cfg 'cfg(docsrs,test)' --check-cfg 'cfg(feature, values())' -C metadata=ff4e1b25a8a80f2e -C extra-filename=-9b09c418ae50edbb --out-dir /opt/rustwide/target/debug/deps -L dependency=/opt/rustwide/target/debug/deps --extern unicode_segmentation=/opt/rustwide/target/debug/deps/libunicode_segmentation-dc98e5380af19de4.rmeta --cap-lints allow --cap-lints=forbid` (never executed)
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   No such file or directory (os error 2)
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "e525acf3a43c33a2dc79f9a1a9e51a50f1cadc9c8f8f6e6f6243ac763916f1f8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e525acf3a43c33a2dc79f9a1a9e51a50f1cadc9c8f8f6e6f6243ac763916f1f8", kill_on_drop: false }`
[INFO] [stdout] e525acf3a43c33a2dc79f9a1a9e51a50f1cadc9c8f8f6e6f6243ac763916f1f8