[INFO] updating cached repository https://github.com/matterinc/plasma_winter
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 923297a9ac6bae1a2923b36354686ed5b824949e
[INFO] checking matterinc/plasma_winter against master#bf1f2eedda4fa02b7c9347dd849ed73ddd43dedc for pr-70917
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmatterinc%2Fplasma_winter" "/workspace/builds/worker-5/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/matterinc/plasma_winter on toolchain bf1f2eedda4fa02b7c9347dd849ed73ddd43dedc
[INFO] running `"/workspace/cargo-home/bin/cargo" "+bf1f2eedda4fa02b7c9347dd849ed73ddd43dedc" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/matterinc/plasma_winter
[INFO] finished tweaking git repo https://github.com/matterinc/plasma_winter
[INFO] tweaked toml for git repo https://github.com/matterinc/plasma_winter written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] crate git repo https://github.com/matterinc/plasma_winter already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+bf1f2eedda4fa02b7c9347dd849ed73ddd43dedc" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+bf1f2eedda4fa02b7c9347dd849ed73ddd43dedc" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] a3756b2bd6b5ede3a8b47732d6881bb91d47995f82960c0b0cbffc7ddfd21192
[INFO] running `"docker" "start" "-a" "a3756b2bd6b5ede3a8b47732d6881bb91d47995f82960c0b0cbffc7ddfd21192"`
[INFO] [stderr]    Compiling serde v1.0.81
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[INFO] [stderr] warning: unnecessary braces around assigned value
[INFO] [stderr]    --> src/sparse_merkle_tree/parallel_smt.rs:135:23
[INFO] [stderr]     |
[INFO] [stderr] 135 |             let cur = { self.nodes[cur_ref].clone() };
[INFO] [stderr]     |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these braces
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_braces)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/server/baby_prover.rs:92:35
[INFO] [stderr]    |
[INFO] [stderr] 92 |     pub fn create(initial_state: &State<Bn256>) ->
[INFO] [stderr]    |                                   ^^^^^^^^^^^^ help: use `dyn`: `dyn State<Bn256>`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/server/account_manager/rest_api.rs:24:19
[INFO] [stderr]    |
[INFO] [stderr] 24 | type BoxFut = Box<Future<Item = Response<Body>, Error = hyper::Error> + Send>;
[INFO] [stderr]    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Future<Item = Response<Body>, Error = hyper::Error> + Send`
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/server/eth/mod.rs:22:45
[INFO] [stderr]    |
[INFO] [stderr] 22 | type Result<T> = std::result::Result<T, Box<std::error::Error>>;
[INFO] [stderr]    |                                             ^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn std::error::Error`
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/server/demo_server/rest_api.rs:74:57
[INFO] [stderr]    |
[INFO] [stderr] 74 | fn send_transaction(req: &HttpRequest<AppState>) -> Box<Future<Item = HttpResponse, Error = Error>> {
[INFO] [stderr]    |                                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Future<Item = HttpResponse, Error = Error>`
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary braces around assigned value
[INFO] [stderr]    --> src/sparse_merkle_tree/parallel_smt.rs:135:23
[INFO] [stderr]     |
[INFO] [stderr] 135 |             let cur = { self.nodes[cur_ref].clone() };
[INFO] [stderr]     |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these braces
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_braces)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/server/baby_prover.rs:92:35
[INFO] [stderr]    |
[INFO] [stderr] 92 |     pub fn create(initial_state: &State<Bn256>) ->
[INFO] [stderr]    |                                   ^^^^^^^^^^^^ help: use `dyn`: `dyn State<Bn256>`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/server/account_manager/rest_api.rs:24:19
[INFO] [stderr]    |
[INFO] [stderr] 24 | type BoxFut = Box<Future<Item = Response<Body>, Error = hyper::Error> + Send>;
[INFO] [stderr]    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Future<Item = Response<Body>, Error = hyper::Error> + Send`
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/server/eth/mod.rs:22:45
[INFO] [stderr]    |
[INFO] [stderr] 22 | type Result<T> = std::result::Result<T, Box<std::error::Error>>;
[INFO] [stderr]    |                                             ^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn std::error::Error`
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/server/demo_server/rest_api.rs:74:57
[INFO] [stderr]    |
[INFO] [stderr] 74 | fn send_transaction(req: &HttpRequest<AppState>) -> Box<Future<Item = HttpResponse, Error = Error>> {
[INFO] [stderr]    |                                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Future<Item = HttpResponse, Error = Error>`
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'std::error::Error::description': use the Display impl or to_string()
[INFO] [stderr]   --> src/server/baby_prover.rs:55:34
[INFO] [stderr]    |
[INFO] [stderr] 55 |             write!(f, "{}", self.description())
[INFO] [stderr]    |                                  ^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(deprecated)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'std::error::Error::description': use the Display impl or to_string()
[INFO] [stderr]   --> src/server/baby_prover.rs:55:34
[INFO] [stderr]    |
[INFO] [stderr] 55 |             write!(f, "{}", self.description())
[INFO] [stderr]    |                                  ^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(deprecated)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/server/baby_prover.rs:245:17
[INFO] [stderr]     |
[INFO] [stderr] 245 |             let mut tree = & mut self.accounts_tree;
[INFO] [stderr]     |                 ----^^^^
[INFO] [stderr]     |                 |
[INFO] [stderr]     |                 help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/server/baby_prover.rs:246:17
[INFO] [stderr]     |
[INFO] [stderr] 246 |             let mut items = tree.items.clone();
[INFO] [stderr]     |                 ----^^^^^
[INFO] [stderr]     |                 |
[INFO] [stderr]     |                 help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/server/baby_prover.rs:290:17
[INFO] [stderr]     |
[INFO] [stderr] 290 |             let mut transaction : Transaction<Bn256> = Transaction {
[INFO] [stderr]     |                 ----^^^^^^^^^^^
[INFO] [stderr]     |                 |
[INFO] [stderr]     |                 help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: this method call currently resolves to `<&[T; N] as IntoIterator>::into_iter` (due to autoref coercions), but that might change in the future when `IntoIterator` impls for arrays are added.
[INFO] [stderr]   --> src/server/eth/signer.rs:73:22
[INFO] [stderr]    |
[INFO] [stderr] 73 |     keccak256(bytes).into_iter().cloned().collect()
[INFO] [stderr]    |                      ^^^^^^^^^ help: use `.iter()` instead of `.into_iter()` to avoid ambiguity: `iter`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(array_into_iter)]` on by default
[INFO] [stderr]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stderr]    = note: for more information, see issue #66145 <https://github.com/rust-lang/rust/issues/66145>
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/server/baby_prover.rs:245:17
[INFO] [stderr]     |
[INFO] [stderr] 245 |             let mut tree = & mut self.accounts_tree;
[INFO] [stderr]     |                 ----^^^^
[INFO] [stderr]     |                 |
[INFO] [stderr]     |                 help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/server/baby_prover.rs:246:17
[INFO] [stderr]     |
[INFO] [stderr] 246 |             let mut items = tree.items.clone();
[INFO] [stderr]     |                 ----^^^^^
[INFO] [stderr]     |                 |
[INFO] [stderr]     |                 help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/server/baby_prover.rs:290:17
[INFO] [stderr]     |
[INFO] [stderr] 290 |             let mut transaction : Transaction<Bn256> = Transaction {
[INFO] [stderr]     |                 ----^^^^^^^^^^^
[INFO] [stderr]     |                 |
[INFO] [stderr]     |                 help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] error[E0596]: cannot borrow `client` as mutable, as it is not declared as mutable
[INFO] [stderr]    --> src/server/eth/mod.rs:213:13
[INFO] [stderr]     |
[INFO] [stderr] 203 |     let client = ETHClient::new(TEST_PLASMA_ALWAYS_VERIFY);
[INFO] [stderr]     |         ------ help: consider changing this to be mutable: `mut client`
[INFO] [stderr] ...
[INFO] [stderr] 213 |     let r = client.commit_block(block_num, total_fees, tx_data_packed, new_root);
[INFO] [stderr]     |             ^^^^^^ cannot borrow as mutable
[INFO] [stderr] 
[INFO] [stderr] error[E0596]: cannot borrow `client` as mutable, as it is not declared as mutable
[INFO] [stderr]    --> src/server/eth/mod.rs:220:13
[INFO] [stderr]     |
[INFO] [stderr] 203 |     let client = ETHClient::new(TEST_PLASMA_ALWAYS_VERIFY);
[INFO] [stderr]     |         ------ help: consider changing this to be mutable: `mut client`
[INFO] [stderr] ...
[INFO] [stderr] 220 |     let r = client.verify_block(block_num, proof);
[INFO] [stderr]     |             ^^^^^^ cannot borrow as mutable
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 2 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0596`.
[INFO] [stderr] error: could not compile `plasma`.
[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] warning: unused import: `Engine`
[INFO] [stderr]   --> src/bin/test_prepared_prover.rs:15:15
[INFO] [stderr]    |
[INFO] [stderr] 15 | use pairing::{Engine};
[INFO] [stderr]    |               ^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/bin/read_write_keys.rs:148:13
[INFO] [stderr]     |
[INFO] [stderr] 148 |         let mut items = tree.items.clone();
[INFO] [stderr]     |             ----^^^^^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/bin/test_prepared_prover.rs:146:13
[INFO] [stderr]     |
[INFO] [stderr] 146 |         let mut items = tree.items.clone();
[INFO] [stderr]     |             ----^^^^^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/bin/prove_128_txes.rs:140:13
[INFO] [stderr]     |
[INFO] [stderr] 140 |         let mut items = tree.items.clone();
[INFO] [stderr]     |             ----^^^^^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `Engine`
[INFO] [stderr]   --> src/bin/test_prepared_prover.rs:15:15
[INFO] [stderr]    |
[INFO] [stderr] 15 | use pairing::{Engine};
[INFO] [stderr]    |               ^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/bin/test_prepared_prover.rs:146:13
[INFO] [stderr]     |
[INFO] [stderr] 146 |         let mut items = tree.items.clone();
[INFO] [stderr]     |             ----^^^^^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/bin/prove_128_txes.rs:140:13
[INFO] [stderr]     |
[INFO] [stderr] 140 |         let mut items = tree.items.clone();
[INFO] [stderr]     |             ----^^^^^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/bin/read_write_keys.rs:148:13
[INFO] [stderr]     |
[INFO] [stderr] 148 |         let mut items = tree.items.clone();
[INFO] [stderr]     |             ----^^^^^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "a3756b2bd6b5ede3a8b47732d6881bb91d47995f82960c0b0cbffc7ddfd21192"`
[INFO] running `"docker" "rm" "-f" "a3756b2bd6b5ede3a8b47732d6881bb91d47995f82960c0b0cbffc7ddfd21192"`
[INFO] [stdout] a3756b2bd6b5ede3a8b47732d6881bb91d47995f82960c0b0cbffc7ddfd21192
