https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/enum.ReifyReason.html
ReifyReason in rustc_middle::ty - Rust
Describes why a `ReifyShim` was created. This is needed to distinguish a ReifyShim created to adjust for things like `#[track_caller]` in a vtable from a...
rustcmiddlety