[INFO] fetching crate exist 0.1.2...
[INFO] checking exist-0.1.2 against try#6f8a6450478f69b8510c8976ab6c2a70b3b0e47c for pr-84920
[INFO] extracting crate exist 0.1.2 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate exist 0.1.2 on toolchain 6f8a6450478f69b8510c8976ab6c2a70b3b0e47c
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6f8a6450478f69b8510c8976ab6c2a70b3b0e47c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate exist 0.1.2
[INFO] finished tweaking crates.io crate exist 0.1.2
[INFO] tweaked toml for crates.io crate exist 0.1.2 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6f8a6450478f69b8510c8976ab6c2a70b3b0e47c" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6f8a6450478f69b8510c8976ab6c2a70b3b0e47c" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+6f8a6450478f69b8510c8976ab6c2a70b3b0e47c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 962dea23930ad01a365fa6229b18b423693dbce6cbdf2eb7cd604f8a34c7f8ef
[INFO] running `Command { std: "docker" "start" "-a" "962dea23930ad01a365fa6229b18b423693dbce6cbdf2eb7cd604f8a34c7f8ef", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "962dea23930ad01a365fa6229b18b423693dbce6cbdf2eb7cd604f8a34c7f8ef", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "962dea23930ad01a365fa6229b18b423693dbce6cbdf2eb7cd604f8a34c7f8ef", kill_on_drop: false }`
[INFO] [stdout] 962dea23930ad01a365fa6229b18b423693dbce6cbdf2eb7cd604f8a34c7f8ef
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+6f8a6450478f69b8510c8976ab6c2a70b3b0e47c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] ea4d416523f17f58ce0d6cf48a56ece1166dbebdddb9c3ce9da474299b5749bd
[INFO] running `Command { std: "docker" "start" "-a" "ea4d416523f17f58ce0d6cf48a56ece1166dbebdddb9c3ce9da474299b5749bd", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde_json v1.0.64
[INFO] [stderr]     Checking half v1.7.1
[INFO] [stderr]     Checking crypto-mac v0.7.0
[INFO] [stderr]     Checking bincode v1.3.3
[INFO] [stderr]     Checking blake2 v0.8.1
[INFO] [stderr]     Checking serde_cbor v0.9.0
[INFO] [stderr]     Checking exist v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] error: ambiguous associated item
[INFO] [stdout]   --> src/data_models/leaf_tree.rs:34:37
[INFO] [stdout]    |
[INFO] [stdout] 34 |         fn visit<V: Visitor<Value = Self::Value>>(&self, v: &mut V) {
[INFO] [stdout]    |                                     ^^^^^^^^^^^ help: use fully-qualified syntax: `<leaf_tree::concrete::Concrete<Value> as View>::Value`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[deny(ambiguous_associated_items)]` on by default
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #57644 <https://github.com/rust-lang/rust/issues/57644>
[INFO] [stdout] note: `Value` could refer to the variant defined here
[INFO] [stdout]   --> src/data_models/leaf_tree.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 26 |         Value(V),
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout] note: `Value` could also refer to the associated type defined here
[INFO] [stdout]   --> src/data_models/mod.rs:14:15
[INFO] [stdout]    |
[INFO] [stdout] 14 |             $(type $Items;)*
[INFO] [stdout]    |               ^^^^^^^^^^^^
[INFO] [stdout]    | 
[INFO] [stdout]   ::: src/data_models/leaf_tree.rs:7:1
[INFO] [stdout]    |
[INFO] [stdout] 7  | Visitable!(View, Visitor, Value);
[INFO] [stdout]    | --------------------------------- in this macro invocation
[INFO] [stdout]    = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: ambiguous associated item
[INFO] [stdout]   --> src/data_models/leaf_tree.rs:34:37
[INFO] [stdout]    |
[INFO] [stdout] 34 |         fn visit<V: Visitor<Value = Self::Value>>(&self, v: &mut V) {
[INFO] [stdout]    |                                     ^^^^^^^^^^^ help: use fully-qualified syntax: `<leaf_tree::concrete::Concrete<Value> as View>::Value`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[deny(ambiguous_associated_items)]` on by default
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #57644 <https://github.com/rust-lang/rust/issues/57644>
[INFO] [stdout] note: `Value` could refer to the variant defined here
[INFO] [stdout]   --> src/data_models/leaf_tree.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 26 |         Value(V),
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout] note: `Value` could also refer to the associated type defined here
[INFO] [stdout]   --> src/data_models/mod.rs:14:15
[INFO] [stdout]    |
[INFO] [stdout] 14 |             $(type $Items;)*
[INFO] [stdout]    |               ^^^^^^^^^^^^
[INFO] [stdout]    | 
[INFO] [stdout]   ::: src/data_models/leaf_tree.rs:7:1
[INFO] [stdout]    |
[INFO] [stdout] 7  | Visitable!(View, Visitor, Value);
[INFO] [stdout]    | --------------------------------- in this macro invocation
[INFO] [stdout]    = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `exist`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "ea4d416523f17f58ce0d6cf48a56ece1166dbebdddb9c3ce9da474299b5749bd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ea4d416523f17f58ce0d6cf48a56ece1166dbebdddb9c3ce9da474299b5749bd", kill_on_drop: false }`
[INFO] [stdout] ea4d416523f17f58ce0d6cf48a56ece1166dbebdddb9c3ce9da474299b5749bd