[INFO] fetching crate fnntw 0.4.1...
[INFO] testing fnntw-0.4.1 against try#8de4c7234dd9b97c9d76b58671343fdbbc9a433e+target=x86_64-unknown-linux-musl for musl_upgrade_1_2_5_with_libc_patch_0
[INFO] extracting crate fnntw 0.4.1 into /workspace/builds/worker-4-tc1/source
[INFO] removed /workspace/builds/worker-4-tc1/source/rust-toolchain.toml
[INFO] started tweaking crates.io crate fnntw 0.4.1
[INFO] finished tweaking crates.io crate fnntw 0.4.1
[INFO] tweaked toml for crates.io crate fnntw 0.4.1 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate fnntw 0.4.1 on toolchain 8de4c7234dd9b97c9d76b58671343fdbbc9a433e
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+8de4c7234dd9b97c9d76b58671343fdbbc9a433e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate fnntw 0.4.1 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" "+8de4c7234dd9b97c9d76b58671343fdbbc9a433e" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded snmalloc-rs v0.3.3
[INFO] [stderr]   Downloaded sync-unsafe-cell v0.1.0
[INFO] [stderr]   Downloaded rpmalloc v0.2.2
[INFO] [stderr]   Downloaded tcmalloc v0.3.0
[INFO] [stderr]   Downloaded tcmalloc-sys v0.3.0
[INFO] [stderr]   Downloaded index-fixed v0.0.2
[INFO] [stderr]   Downloaded seq-macro v0.3.3
[INFO] [stderr]   Downloaded kth v0.1.0
[INFO] [stderr]   Downloaded mimalloc v0.1.34
[INFO] [stderr]   Downloaded pdqselect v0.1.1
[INFO] [stderr]   Downloaded ouroboros v0.15.6
[INFO] [stderr]   Downloaded likely_stable v0.1.2
[INFO] [stderr]   Downloaded concat-idents v1.1.4
[INFO] [stderr]   Downloaded jemallocator v0.5.0
[INFO] [stderr]   Downloaded rpmalloc-sys v0.2.3+b097fd0
[INFO] [stderr]   Downloaded floydrivest v0.2.4
[INFO] [stderr]   Downloaded serde_derive v1.0.156
[INFO] [stderr]   Downloaded ouroboros_macro v0.15.6
[INFO] [stderr]   Downloaded jemalloc-sys v0.5.3+5.3.0-patched
[INFO] [stderr]   Downloaded libmimalloc-sys v0.1.30
[INFO] [stderr]   Downloaded adqselect v0.1.3
[INFO] [stderr]   Downloaded snmalloc-sys v0.3.3
[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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+8de4c7234dd9b97c9d76b58671343fdbbc9a433e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e023610303b770147b2404fd57ac197a406fd5f82ea7a61514320cda8b7ce3c1
[INFO] running `Command { std: "docker" "start" "-a" "e023610303b770147b2404fd57ac197a406fd5f82ea7a61514320cda8b7ce3c1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e023610303b770147b2404fd57ac197a406fd5f82ea7a61514320cda8b7ce3c1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e023610303b770147b2404fd57ac197a406fd5f82ea7a61514320cda8b7ce3c1", kill_on_drop: false }`
[INFO] [stdout] e023610303b770147b2404fd57ac197a406fd5f82ea7a61514320cda8b7ce3c1
[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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+8de4c7234dd9b97c9d76b58671343fdbbc9a433e" "build" "--frozen" "--message-format=json" "--target" "x86_64-unknown-linux-musl", kill_on_drop: false }`
[INFO] [stdout] 862715c0e5c3ab096336448357e5802e78de3115ac2ce9044fa9573251eaae41
[INFO] running `Command { std: "docker" "start" "-a" "862715c0e5c3ab096336448357e5802e78de3115ac2ce9044fa9573251eaae41", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.51
[INFO] [stderr]    Compiling quote v1.0.23
[INFO] [stderr]    Compiling unicode-ident v1.0.8
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]    Compiling thiserror v1.0.39
[INFO] [stderr]    Compiling ucd-trie v0.1.5
[INFO] [stderr]    Compiling crossbeam-utils v0.8.15
[INFO] [stderr]    Compiling libc v0.2.139
[INFO] [stderr]    Compiling scopeguard v1.1.0
[INFO] [stderr]    Compiling rayon-core v1.11.0
[INFO] [stderr]    Compiling const_fn v0.4.9
[INFO] [stderr]    Compiling Inflector v0.11.4
[INFO] [stderr]    Compiling itoa v1.0.6
[INFO] [stderr]    Compiling memoffset v0.8.0
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.14
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling num-traits v0.2.15
[INFO] [stderr]    Compiling either v1.8.1
[INFO] [stderr]    Compiling aliasable v0.1.3
[INFO] [stderr]    Compiling arrayvec v0.7.2
[INFO] [stderr]    Compiling permutation v0.4.1
[INFO] [stderr]    Compiling sync-unsafe-cell v0.1.0
[INFO] [stderr]    Compiling num-format v0.4.4
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/proc-macro2-1.0.51/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 crossbeam-channel v0.5.7
[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" "862715c0e5c3ab096336448357e5802e78de3115ac2ce9044fa9573251eaae41", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "862715c0e5c3ab096336448357e5802e78de3115ac2ce9044fa9573251eaae41", kill_on_drop: false }`
[INFO] [stdout] 862715c0e5c3ab096336448357e5802e78de3115ac2ce9044fa9573251eaae41