these 4 derivations will be built:
  /nix/store/xm2ma0kbyxia4ykl0pk2c2aw145ihdc7-Cargo.toml.drv
  /nix/store/g2fg4ypncb6airipfqiwny553p9sv1h4-source.drv
  /nix/store/zz75xp5mjh5siy49pchjb893phxhk88i-tincd-deps-0.1.0.drv
  /nix/store/6q0gavqw7ji0k1lbasf3jmsnkiil74fz-tincd-clippy-0.1.0.drv
error: Cannot build '/nix/store/6q0gavqw7ji0k1lbasf3jmsnkiil74fz-tincd-clippy-0.1.0.drv'.
       Reason: builder failed with exit code 101.
       Output paths:
         /nix/store/gz64gvgl3w75sxcmvy25krwi37r1cw9f-tincd-clippy-0.1.0
       Last 25 log lines:
       >    Compiling getrandom v0.3.4
       >     Checking wait-timeout v0.2.1
       >     Checking quick-error v1.2.3
       >     Checking fnv v1.0.7
       >     Checking bit-vec v0.8.0
       >     Checking regex-syntax v0.8.11
       >     Checking unarray v0.1.4
       >     Checking arbitrary v1.5.0
       >     Checking inout v0.2.2
       >     Checking hex v0.4.3
       >     Checking bit-set v0.8.0
       >     Checking cipher v0.5.2
       > error: variable does not need to be mutable
       >    --> crates/tinc-device/tests/utun_batch.rs:163:13
       >     |
       > 163 |         let mut f = ip4_udp_frame([10, 98, 2, 2], [10, 98, 2, 1], 50000, port, 24 + i);
       >     |             ----^
       >     |             |
       >     |             help: remove this `mut`
       >     |
       >     = note: `-D unused-mut` implied by `-D warnings`
       >     = help: to override `-D warnings` add `#[allow(unused_mut)]`
       >
       > error: could not compile `tinc-device` (test "utun_batch") due to 1 previous error
       > warning: build failed, waiting for other jobs to finish...
       For full logs, run:
         nix log /nix/store/6q0gavqw7ji0k1lbasf3jmsnkiil74fz-tincd-clippy-0.1.0.drv