cargo clean && cargo check --lib && git apply add-dyn.patch && cargo check --lib ; git apply -R add-dyn.patch # ICE on the second cargo check

add-dyn.patch

diff --git a/config.rs b/config.rs
index 8b1a9599656d..8ca857920353 100644
--- a/config.rs
+++ b/config.rs
@@ -5,7 +5,7 @@ use std::io::Write;
 #[derive(Deserialize)]
 pub struct Configuration {
     #[serde(deserialize_with = "find_instrument")]
-    pub instrument: Box<Write>,
+    pub instrument: Box<dyn Write>,
 }
 
 fn find_instrument<'de, D>(_de: D) -> Result<Box<dyn Write>, D::Error>

Cargo.toml

[package]
authors = []
name = "incremental-ice"
version = "0.0.0"

[dependencies]
serde = "1.0.0"
serde_derive = "1.0.0"

[lib]
path = "lib.rs"

config.rs

use serde::de::{Deserializer};

use std::io::Write;

#[derive(Deserialize)]
pub struct Configuration {
    #[serde(deserialize_with = "find_instrument")]
    pub instrument: Box<Write>,
}

fn find_instrument<'de, D>(_de: D) -> Result<Box<dyn Write>, D::Error>
where
    D: Deserializer<'de>,
{
    Ok(Box::new(vec![]))
}

lib.rs

extern crate serde;
#[macro_use]
extern crate serde_derive;

pub mod config;