[INFO] fetching crate microtensor 0.1.5...
[INFO] checking microtensor-0.1.5 against try#a4980311fb7bb9e7893708e6bd3fbbfb2819fd3d for pr-145342-1
[INFO] extracting crate microtensor 0.1.5 into /workspace/builds/worker-6-tc2/source
[INFO] started tweaking crates.io crate microtensor 0.1.5
[INFO] finished tweaking crates.io crate microtensor 0.1.5
[INFO] tweaked toml for crates.io crate microtensor 0.1.5 written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate microtensor 0.1.5 on toolchain a4980311fb7bb9e7893708e6bd3fbbfb2819fd3d
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+a4980311fb7bb9e7893708e6bd3fbbfb2819fd3d" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate microtensor 0.1.5 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" "+a4980311fb7bb9e7893708e6bd3fbbfb2819fd3d" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:7ad1b28ee6f5f7f699f6cf7015098d6ccdd96d6f2d78dd06228f5b4c9faf309c" "/opt/rustwide/cargo-home/bin/cargo" "+a4980311fb7bb9e7893708e6bd3fbbfb2819fd3d" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 58c56411a32abf4283965ebd5044061c1b9c828329fda613afc1355ea2dcad39
[INFO] running `Command { std: "docker" "start" "-a" "58c56411a32abf4283965ebd5044061c1b9c828329fda613afc1355ea2dcad39", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "58c56411a32abf4283965ebd5044061c1b9c828329fda613afc1355ea2dcad39", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "58c56411a32abf4283965ebd5044061c1b9c828329fda613afc1355ea2dcad39", kill_on_drop: false }`
[INFO] [stdout] 58c56411a32abf4283965ebd5044061c1b9c828329fda613afc1355ea2dcad39
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:7ad1b28ee6f5f7f699f6cf7015098d6ccdd96d6f2d78dd06228f5b4c9faf309c" "/opt/rustwide/cargo-home/bin/cargo" "+a4980311fb7bb9e7893708e6bd3fbbfb2819fd3d" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 17db8b4b4794f5edc7f03e75f9313cdc6179787057aabbb8f4993f42bf93054f
[INFO] running `Command { std: "docker" "start" "-a" "17db8b4b4794f5edc7f03e75f9313cdc6179787057aabbb8f4993f42bf93054f", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.137
[INFO] [stderr]    Compiling proc-macro2 v1.0.47
[INFO] [stderr]    Compiling quote v1.0.21
[INFO] [stderr]    Compiling unicode-ident v1.0.5
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]    Compiling syn v1.0.103
[INFO] [stderr]    Compiling serde_derive v1.0.147
[INFO] [stderr]    Compiling serde v1.0.147
[INFO] [stderr]    Compiling typenum v1.15.0
[INFO] [stderr]     Checking byteorder v1.4.3
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling version_check v0.9.4
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]     Checking stable_deref_trait v1.2.0
[INFO] [stderr]    Compiling semver v1.0.14
[INFO] [stderr]    Compiling lock_api v0.4.9
[INFO] [stderr]    Compiling generic-array v0.14.6
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]    Compiling nix v0.15.0
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/proc-macro2-1.0.47/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 heapless v0.5.6
[INFO] [stderr]    Compiling build_id v0.2.1
[INFO] [stderr]     Checking bitflags v1.3.2
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]     Checking hash32 v0.1.1
[INFO] [stderr]    Compiling getrandom v0.1.16
[INFO] [stderr]     Checking nom v2.2.1
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]     Checking void v1.0.2
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]    Compiling crossbeam-utils v0.8.13
[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" "17db8b4b4794f5edc7f03e75f9313cdc6179787057aabbb8f4993f42bf93054f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "17db8b4b4794f5edc7f03e75f9313cdc6179787057aabbb8f4993f42bf93054f", kill_on_drop: false }`
[INFO] [stdout] 17db8b4b4794f5edc7f03e75f9313cdc6179787057aabbb8f4993f42bf93054f