[INFO] fetching crate varnamer 0.1.0...
[INFO] testing varnamer-0.1.0 against master#caccb4d0368bd918ef6668af8e13834d07040417 for pr-146098-1
[INFO] extracting crate varnamer 0.1.0 into /workspace/builds/worker-5-tc1/source
[INFO] started tweaking crates.io crate varnamer 0.1.0
[INFO] finished tweaking crates.io crate varnamer 0.1.0
[INFO] tweaked toml for crates.io crate varnamer 0.1.0 written to /workspace/builds/worker-5-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate varnamer 0.1.0 on toolchain caccb4d0368bd918ef6668af8e13834d07040417
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+caccb4d0368bd918ef6668af8e13834d07040417" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate varnamer 0.1.0 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" "+caccb4d0368bd918ef6668af8e13834d07040417" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded thiserror v1.0.39
[INFO] [stderr]   Downloaded proc-macro2 v1.0.51
[INFO] [stderr]   Downloaded rustls v0.20.8
[INFO] [stderr]   Downloaded windows_aarch64_msvc v0.42.1
[INFO] [stderr]   Downloaded serde v1.0.154
[INFO] [stderr]   Downloaded thiserror-impl v1.0.39
[INFO] [stderr]   Downloaded serde_derive v1.0.154
[INFO] [stderr]   Downloaded windows_i686_gnu v0.42.1
[INFO] [stderr]   Downloaded windows-targets v0.42.1
[INFO] [stderr]   Downloaded windows_aarch64_gnullvm v0.42.1
[INFO] [stderr]   Downloaded windows_x86_64_gnu v0.42.1
[INFO] [stderr]   Downloaded windows_x86_64_msvc v0.42.1
[INFO] [stderr]   Downloaded confy v0.5.1
[INFO] [stderr]   Downloaded unicode-bidi v0.3.11
[INFO] [stderr]   Downloaded ureq v2.6.2
[INFO] [stderr]   Downloaded windows_i686_msvc v0.42.1
[INFO] [stderr]   Downloaded windows_x86_64_gnullvm v0.42.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+caccb4d0368bd918ef6668af8e13834d07040417" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d25f00d286a8225ed4fb8062afca5a13c888f9df3419cfb3e73556aabfffcc34
[INFO] running `Command { std: "docker" "start" "-a" "d25f00d286a8225ed4fb8062afca5a13c888f9df3419cfb3e73556aabfffcc34", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d25f00d286a8225ed4fb8062afca5a13c888f9df3419cfb3e73556aabfffcc34", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d25f00d286a8225ed4fb8062afca5a13c888f9df3419cfb3e73556aabfffcc34", kill_on_drop: false }`
[INFO] [stdout] d25f00d286a8225ed4fb8062afca5a13c888f9df3419cfb3e73556aabfffcc34
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+caccb4d0368bd918ef6668af8e13834d07040417" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 462b793ef69f98cc623a950c06a8dba6df2a37b94fd2ffecf4c7f6869d2abf0e
[INFO] running `Command { std: "docker" "start" "-a" "462b793ef69f98cc623a950c06a8dba6df2a37b94fd2ffecf4c7f6869d2abf0e", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.51
[INFO] [stderr]    Compiling quote v1.0.23
[INFO] [stderr]    Compiling libc v0.2.139
[INFO] [stderr]    Compiling cc v1.0.79
[INFO] [stderr]    Compiling serde_derive v1.0.154
[INFO] [stderr]    Compiling serde v1.0.154
[INFO] [stderr]    Compiling thiserror v1.0.39
[INFO] [stderr]    Compiling unicode-normalization v0.1.22
[INFO] [stderr]    Compiling unicode-bidi v0.3.11
[INFO] [stderr]    Compiling rustls v0.20.8
[INFO] [stderr]    Compiling serde_json v1.0.94
[INFO] [stderr]    Compiling miniz_oxide v0.6.2
[INFO] [stderr]    Compiling ryu v1.0.13
[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 flate2 v1.0.25
[INFO] [stderr]    Compiling idna v0.3.0
[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" "462b793ef69f98cc623a950c06a8dba6df2a37b94fd2ffecf4c7f6869d2abf0e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "462b793ef69f98cc623a950c06a8dba6df2a37b94fd2ffecf4c7f6869d2abf0e", kill_on_drop: false }`
[INFO] [stdout] 462b793ef69f98cc623a950c06a8dba6df2a37b94fd2ffecf4c7f6869d2abf0e