[INFO] fetching crate fastvarint 0.22.0...
[INFO] checking fastvarint-0.22.0 against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] extracting crate fastvarint 0.22.0 into /workspace/builds/worker-2-tc2/source
[INFO] started tweaking crates.io crate fastvarint 0.22.0
[INFO] finished tweaking crates.io crate fastvarint 0.22.0
[INFO] tweaked toml for crates.io crate fastvarint 0.22.0 written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate fastvarint 0.22.0 on toolchain 4f260f0f20b3133d20cfb50353c0221943af5796
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]      Locking 13 packages to latest compatible versions
[INFO] [stderr]       Adding derive_more v1.0.0 (available: v2.0.1)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/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" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4207a0bdac70775a10f76a92fc9218131b9e4d5affd7d9f65692ae04b88908cb
[INFO] running `Command { std: "docker" "start" "-a" "4207a0bdac70775a10f76a92fc9218131b9e4d5affd7d9f65692ae04b88908cb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4207a0bdac70775a10f76a92fc9218131b9e4d5affd7d9f65692ae04b88908cb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4207a0bdac70775a10f76a92fc9218131b9e4d5affd7d9f65692ae04b88908cb", kill_on_drop: false }`
[INFO] [stdout] 4207a0bdac70775a10f76a92fc9218131b9e4d5affd7d9f65692ae04b88908cb
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/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 -Dunmustuse_in_always_ok" "-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" "+4f260f0f20b3133d20cfb50353c0221943af5796" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2702db7316c862fb41ffa96b03219bee61a5418db7f83dca7ef71ba747079617
[INFO] running `Command { std: "docker" "start" "-a" "2702db7316c862fb41ffa96b03219bee61a5418db7f83dca7ef71ba747079617", kill_on_drop: false }`
[INFO] [stderr]    Compiling derive_more-impl v1.0.0
[INFO] [stderr]     Checking nonmax v0.5.5
[INFO] [stderr]     Checking derive_more v1.0.0
[INFO] [stderr]     Checking fastvarint v0.22.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `convert::Infallible`, `marker::PhantomData`, and `usize`
[INFO] [stdout]  --> src/serde.rs:1:11
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{convert::Infallible, marker::PhantomData, usize};
[INFO] [stdout]   |           ^^^^^^^^^^^^^^^^^^^  ^^^^^^^^^^^^^^^^^^^  ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Unexpected` and `Visitor`
[INFO] [stdout]  --> src/serde.rs:3:17
[INFO] [stdout]   |
[INFO] [stdout] 3 | use serde::de::{Unexpected, Visitor};
[INFO] [stdout]   |                 ^^^^^^^^^^  ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `DecodeVarIntError` and `DecodeVarInt`
[INFO] [stdout]  --> src/serde.rs:5:13
[INFO] [stdout]   |
[INFO] [stdout] 5 | use crate::{DecodeVarInt, DecodeVarIntError, EncodeVarInt};
[INFO] [stdout]   |             ^^^^^^^^^^^^  ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `convert::Infallible`, `marker::PhantomData`, and `usize`
[INFO] [stdout]  --> src/serde.rs:1:11
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{convert::Infallible, marker::PhantomData, usize};
[INFO] [stdout]   |           ^^^^^^^^^^^^^^^^^^^  ^^^^^^^^^^^^^^^^^^^  ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Unexpected` and `Visitor`
[INFO] [stdout]  --> src/serde.rs:3:17
[INFO] [stdout]   |
[INFO] [stdout] 3 | use serde::de::{Unexpected, Visitor};
[INFO] [stdout]   |                 ^^^^^^^^^^  ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `DecodeVarIntError` and `DecodeVarInt`
[INFO] [stdout]  --> src/serde.rs:5:13
[INFO] [stdout]   |
[INFO] [stdout] 5 | use crate::{DecodeVarInt, DecodeVarIntError, EncodeVarInt};
[INFO] [stdout]   |             ^^^^^^^^^^^^  ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<std::option::Option<u8>, Infallible>
[INFO] [stdout]   --> src/tests.rs:17:91
[INFO] [stdout]    |
[INFO] [stdout] 17 |       let result: Result<(T, usize), DecodeVarIntError<Infallible>> = T::decode_var_int(|_| {
[INFO] [stdout]    |  ___________________________________________________________________________________________^
[INFO] [stdout] 18 | |         if i < bytes.len() {
[INFO] [stdout] 19 | |             let byte = bytes[i];
[INFO] [stdout] 20 | |             i += 1;
[INFO] [stdout] ...  |
[INFO] [stdout] 25 | |     });
[INFO] [stdout]    | |_____^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<std::option::Option<u8>, Infallible>
[INFO] [stdout]   --> src/tests.rs:18:9
[INFO] [stdout]    |
[INFO] [stdout] 18 | /         if i < bytes.len() {
[INFO] [stdout] 19 | |             let byte = bytes[i];
[INFO] [stdout] 20 | |             i += 1;
[INFO] [stdout] 21 | |             Ok(Some(byte))
[INFO] [stdout] 22 | |         } else {
[INFO] [stdout] 23 | |             Ok(None)
[INFO] [stdout] 24 | |         }
[INFO] [stdout]    | |_________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<std::option::Option<u8>, Infallible>
[INFO] [stdout]   --> src/tests.rs:18:28
[INFO] [stdout]    |
[INFO] [stdout] 18 |           if i < bytes.len() {
[INFO] [stdout]    |  ____________________________^
[INFO] [stdout] 19 | |             let byte = bytes[i];
[INFO] [stdout] 20 | |             i += 1;
[INFO] [stdout] 21 | |             Ok(Some(byte))
[INFO] [stdout] 22 | |         } else {
[INFO] [stdout]    | |_________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<std::option::Option<u8>, Infallible>
[INFO] [stdout]   --> src/tests.rs:21:13
[INFO] [stdout]    |
[INFO] [stdout] 21 |             Ok(Some(byte))
[INFO] [stdout]    |             ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<std::option::Option<u8>, Infallible>
[INFO] [stdout]   --> src/tests.rs:22:16
[INFO] [stdout]    |
[INFO] [stdout] 22 |           } else {
[INFO] [stdout]    |  ________________^
[INFO] [stdout] 23 | |             Ok(None)
[INFO] [stdout] 24 | |         }
[INFO] [stdout]    | |_________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<std::option::Option<u8>, Infallible>
[INFO] [stdout]   --> src/tests.rs:23:13
[INFO] [stdout]    |
[INFO] [stdout] 23 |             Ok(None)
[INFO] [stdout]    |             ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `fastvarint` (lib test) due to 6 previous errors; 3 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "2702db7316c862fb41ffa96b03219bee61a5418db7f83dca7ef71ba747079617", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2702db7316c862fb41ffa96b03219bee61a5418db7f83dca7ef71ba747079617", kill_on_drop: false }`
[INFO] [stdout] 2702db7316c862fb41ffa96b03219bee61a5418db7f83dca7ef71ba747079617