hreq fails to build on stable rust 1.46.0

[algesten]

error: reached the type-length limit while instantiating `<std::boxed::Box<std::future::fr..., ()}]>>, ()}]>, ()}]>>>>>::into`
   --> /Users/martin/.rustup/toolchains/stable-x86_64-apple-darwin/lib/rustlib/src/rust/src/libcore/convert/mod.rs:559:5
    |
559 | /     fn into(self) -> U {
560 | |         U::from(self)
561 | |     }
    | |_____^
    |
    = note: consider adding a `#![type_length_limit="1527629"]` attribute to your crate

The problem seems to be due to using tracing::instrument of async blocks.

Related:

rust-lang/rust#75992
rust-lang/rust#54540 (comment)
tokio-rs/tracing#616

[algesten]

---

Regression in 0a49057dd35d9bd2fcc9760a054809c30eee2a58

---

searched nightlies: from nightly-2020-08-12 to nightly-2020-08-15
regressed nightly: nightly-2020-08-14
searched commits: from rust-lang/rust@576d27c to rust-lang/rust@81dc88f
regressed commit: rust-lang/rust@0a49057

bisected with cargo-bisect-rustc v0.5.2

Host triple: x86_64-apple-darwin
Reproduce with:

cargo bisect-rustc --start=2020-08-12 --end=2020-08-15