[INFO] fetching crate mdbook-tag 0.0.2...
[INFO] checking mdbook-tag-0.0.2 against master#936f2600b6c903b04387f74ed5cbce88bb06d243 for pr-91141
[INFO] extracting crate mdbook-tag 0.0.2 into /workspace/builds/worker-31/source
[INFO] validating manifest of crates.io crate mdbook-tag 0.0.2 on toolchain 936f2600b6c903b04387f74ed5cbce88bb06d243
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+936f2600b6c903b04387f74ed5cbce88bb06d243" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mdbook-tag 0.0.2
[INFO] finished tweaking crates.io crate mdbook-tag 0.0.2
[INFO] tweaked toml for crates.io crate mdbook-tag 0.0.2 written to /workspace/builds/worker-31/source/Cargo.toml
[INFO] crate crates.io crate mdbook-tag 0.0.2 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+936f2600b6c903b04387f74ed5cbce88bb06d243" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+936f2600b6c903b04387f74ed5cbce88bb06d243" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b5d8507dd5337fe1d4c102b18daa85f538d6b93168fa01200622efffee0d947a
[INFO] running `Command { std: "docker" "start" "-a" "b5d8507dd5337fe1d4c102b18daa85f538d6b93168fa01200622efffee0d947a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b5d8507dd5337fe1d4c102b18daa85f538d6b93168fa01200622efffee0d947a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b5d8507dd5337fe1d4c102b18daa85f538d6b93168fa01200622efffee0d947a", kill_on_drop: false }`
[INFO] [stdout] b5d8507dd5337fe1d4c102b18daa85f538d6b93168fa01200622efffee0d947a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+936f2600b6c903b04387f74ed5cbce88bb06d243" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3f9579d0c6b7e39a165e6cd90afb4d332deeab13e9776a5448cfe41dc47d02ef
[INFO] running `Command { std: "docker" "start" "-a" "3f9579d0c6b7e39a165e6cd90afb4d332deeab13e9776a5448cfe41dc47d02ef", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.66
[INFO] [stderr]    Compiling autocfg v0.1.7
[INFO] [stderr]    Compiling proc-macro2 v1.0.6
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]    Compiling syn v1.0.11
[INFO] [stderr]    Compiling serde v1.0.103
[INFO] [stderr]    Compiling ryu v1.0.2
[INFO] [stderr]     Checking matches v0.1.8
[INFO] [stderr]    Compiling byteorder v1.3.2
[INFO] [stderr]     Checking smallvec v1.0.0
[INFO] [stderr]     Checking siphasher v0.2.3
[INFO] [stderr]    Compiling string_cache_shared v0.3.0
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling memchr v2.2.1
[INFO] [stderr]    Compiling getrandom v0.1.13
[INFO] [stderr]    Compiling cc v1.0.47
[INFO] [stderr]     Checking traitobject v0.1.0
[INFO] [stderr]    Compiling typenum v1.11.2
[INFO] [stderr]    Compiling itoa v0.4.4
[INFO] [stderr]     Checking new_debug_unreachable v1.0.3
[INFO] [stderr]     Checking mac v0.1.1
[INFO] [stderr]     Checking ppv-lite86 v0.2.6
[INFO] [stderr]    Compiling ident_case v1.0.1
[INFO] [stderr]    Compiling fnv v1.0.6
[INFO] [stderr]     Checking unicode-width v0.1.6
[INFO] [stderr]    Compiling ucd-trie v0.1.2
[INFO] [stderr]     Checking byte-tools v0.3.1
[INFO] [stderr]     Checking rustc-demangle v0.1.16
[INFO] [stderr]    Compiling maplit v1.0.2
[INFO] [stderr]     Checking slab v0.4.2
[INFO] [stderr]     Checking precomputed-hash v0.1.1
[INFO] [stderr]     Checking regex-syntax v0.6.12
[INFO] [stderr]     Checking utf-8 v0.7.5
[INFO] [stderr]     Checking typeable v0.1.2
[INFO] [stderr]    Compiling failure_derive v0.1.6
[INFO] [stderr]     Checking lazycell v1.2.1
[INFO] [stderr]    Compiling pulldown-cmark v0.5.3
[INFO] [stderr]     Checking modifier v0.1.0
[INFO] [stderr]     Checking quick-error v1.2.2
[INFO] [stderr]    Compiling unicode-segmentation v1.6.0
[INFO] [stderr]     Checking same-file v1.0.5
[INFO] [stderr]     Checking opaque-debug v0.2.3
[INFO] [stderr]     Checking fake-simd v0.1.2
[INFO] [stderr]     Checking sequence_trie v0.3.6
[INFO] [stderr]     Checking remove_dir_all v0.5.2
[INFO] [stderr]     Checking is-match v0.1.0
[INFO] [stderr]     Checking strum v0.15.0
[INFO] [stderr]     Checking either v1.5.3
[INFO] [stderr]     Checking termcolor v1.0.5
[INFO] [stderr]     Checking open v1.3.2
[INFO] [stderr]     Checking shlex v0.1.1
[INFO] [stderr]    Compiling unicase v1.4.2
[INFO] [stderr]    Compiling error-chain v0.12.1
[INFO] [stderr]     Checking gitignore v1.0.6
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr] error: could not compile `serde`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustc --crate-name serde /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/serde-1.0.103/src/lib.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type lib --emit=dep-info,metadata -C embed-bitcode=no -C debuginfo=2 --cfg 'feature="default"' --cfg 'feature="std"' -C metadata=b9bce4a3199b6f92 -C extra-filename=-b9bce4a3199b6f92 --out-dir /opt/rustwide/target/debug/deps -L dependency=/opt/rustwide/target/debug/deps --cap-lints allow --cap-lints=forbid --cfg ops_bound --cfg core_reverse --cfg de_boxed_c_str --cfg de_boxed_path --cfg de_rc_dst --cfg core_duration --cfg integer128 --cfg range_inclusive --cfg num_nonzero --cfg core_try_from --cfg num_nonzero_signed --cfg std_atomic64 --cfg std_atomic` (signal: 9, SIGKILL: kill)
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "3f9579d0c6b7e39a165e6cd90afb4d332deeab13e9776a5448cfe41dc47d02ef", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3f9579d0c6b7e39a165e6cd90afb4d332deeab13e9776a5448cfe41dc47d02ef", kill_on_drop: false }`
[INFO] [stdout] 3f9579d0c6b7e39a165e6cd90afb4d332deeab13e9776a5448cfe41dc47d02ef