[INFO] fetching crate mamba 0.3.6...
[INFO] testing mamba-0.3.6 against master#c90bcb9571b7aab0d8beaa2ce8a998ffaf079d38 for pr-146098-8
[INFO] extracting crate mamba 0.3.6 into /workspace/builds/worker-0-tc1/source
[INFO] started tweaking crates.io crate mamba 0.3.6
[INFO] finished tweaking crates.io crate mamba 0.3.6
[INFO] tweaked toml for crates.io crate mamba 0.3.6 written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate mamba 0.3.6 on toolchain c90bcb9571b7aab0d8beaa2ce8a998ffaf079d38
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+c90bcb9571b7aab0d8beaa2ce8a998ffaf079d38" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate mamba 0.3.6 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" "+c90bcb9571b7aab0d8beaa2ce8a998ffaf079d38" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded remove_dir_all v0.5.3
[INFO] [stderr]   Downloaded nom_locate v0.3.1
[INFO] [stderr]   Downloaded tempfile v3.3.0
[INFO] [stderr]   Downloaded predicates-core v1.0.5
[INFO] [stderr]   Downloaded pathdiff v0.1.0
[INFO] [stderr]   Downloaded itoa v1.0.4
[INFO] [stderr]   Downloaded unicode-ident v1.0.5
[INFO] [stderr]   Downloaded ryu v1.0.11
[INFO] [stderr]   Downloaded proc-macro2 v1.0.47
[INFO] [stderr]   Downloaded quote v1.0.21
[INFO] [stderr]   Downloaded itertools v0.8.2
[INFO] [stderr]   Downloaded serde_derive v1.0.151
[INFO] [stderr]   Downloaded nom v4.2.3
[INFO] [stderr]   Downloaded serde_json v1.0.89
[INFO] [stderr]   Downloaded serde v1.0.151
[INFO] [stderr]   Downloaded bytecount v0.3.2
[INFO] [stderr]   Downloaded python-parser v0.1.0
[INFO] [stderr]   Downloaded syn v1.0.105
[INFO] [stderr]   Downloaded predicates v1.0.8
[INFO] [stderr]   Downloaded assert_cmd v0.10.2
[INFO] [stderr]   Downloaded either v1.8.0
[INFO] [stderr]   Downloaded permutate v0.3.2
[INFO] [stderr]   Downloaded escargot v0.3.1
[INFO] [stderr]   Downloaded unicode_names2 v0.2.2
[INFO] [stderr]   Downloaded loggerv v0.7.2
[INFO] [stderr]   Downloaded num-traits v0.2.15
[INFO] [stderr]   Downloaded termtree v0.4.0
[INFO] [stderr]   Downloaded predicates-tree v1.0.7
[INFO] [stderr]   Downloaded wtf8 v0.0.3
[INFO] [stderr]   Downloaded fastrand v1.8.0
[INFO] [stderr]   Downloaded libc v0.2.138
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+c90bcb9571b7aab0d8beaa2ce8a998ffaf079d38" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4b40b3199cae55b59eb56838228864382cc766ad28dfa9f96bdb7f132d954d48
[INFO] running `Command { std: "docker" "start" "-a" "4b40b3199cae55b59eb56838228864382cc766ad28dfa9f96bdb7f132d954d48", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4b40b3199cae55b59eb56838228864382cc766ad28dfa9f96bdb7f132d954d48", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4b40b3199cae55b59eb56838228864382cc766ad28dfa9f96bdb7f132d954d48", kill_on_drop: false }`
[INFO] [stdout] 4b40b3199cae55b59eb56838228864382cc766ad28dfa9f96bdb7f132d954d48
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+c90bcb9571b7aab0d8beaa2ce8a998ffaf079d38" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] de61a4e74f8e798aeeeef9287d5ac362d1eac6753d63772b7c2b36ffdb61134d
[INFO] running `Command { std: "docker" "start" "-a" "de61a4e74f8e798aeeeef9287d5ac362d1eac6753d63772b7c2b36ffdb61134d", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.1.0
[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]    Compiling syn v1.0.105
[INFO] [stderr]    Compiling serde_derive v1.0.151
[INFO] [stderr]    Compiling libc v0.2.138
[INFO] [stderr]    Compiling memchr v2.5.0
[INFO] [stderr]    Compiling serde v1.0.151
[INFO] [stderr]    Compiling version_check v0.1.5
[INFO] [stderr]    Compiling serde_json v1.0.89
[INFO] [stderr]    Compiling itoa v1.0.4
[INFO] [stderr]    Compiling predicates-core v1.0.5
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]    Compiling escargot v0.3.1
[INFO] [stderr]    Compiling ryu v1.0.11
[INFO] [stderr]    Compiling unicode-width v0.1.10
[INFO] [stderr]    Compiling ansi_term v0.12.1
[INFO] [stderr]    Compiling bytecount v0.3.2
[INFO] [stderr]    Compiling difference v2.0.0
[INFO] [stderr]    Compiling termtree v0.4.0
[INFO] [stderr]    Compiling textwrap v0.11.0
[INFO] [stderr]    Compiling wtf8 v0.0.3
[INFO] [stderr]    Compiling predicates v1.0.8
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling predicates-tree v1.0.7
[INFO] [stderr]    Compiling unicode_names2 v0.2.2
[INFO] [stderr]    Compiling either v1.8.0
[INFO] [stderr]    Compiling yaml-rust v0.3.5
[INFO] [stderr]    Compiling strsim v0.8.0
[INFO] [stderr]    Compiling vec_map v0.8.2
[INFO] [stderr]    Compiling fastrand v1.8.0
[INFO] [stderr]    Compiling remove_dir_all v0.5.3
[INFO] [stderr]    Compiling permutate v0.3.2
[INFO] [stderr]    Compiling nom v4.2.3
[INFO] [stderr]    Compiling glob v0.3.0
[INFO] [stderr]    Compiling pathdiff v0.1.0
[INFO] [stderr]    Compiling num-traits v0.2.15
[INFO] [stderr]    Compiling num-integer v0.1.45
[INFO] [stderr]    Compiling num-bigint v0.2.6
[INFO] [stderr]    Compiling itertools v0.8.2
[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] [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" "de61a4e74f8e798aeeeef9287d5ac362d1eac6753d63772b7c2b36ffdb61134d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "de61a4e74f8e798aeeeef9287d5ac362d1eac6753d63772b7c2b36ffdb61134d", kill_on_drop: false }`
[INFO] [stdout] de61a4e74f8e798aeeeef9287d5ac362d1eac6753d63772b7c2b36ffdb61134d
