rust-lang / rust-lang/rust

Incorrect rustdoc rendering of const generic default

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#133,848 1 comment 0 reactions 1 assignee View on GitHub

@lms0806 is already working on this.

Since May 29, 2026.

A-const-generics A-cross-crate-reexports C-bug T-rustdoc
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Description

I tried this code:

https://doc.rust-lang.org/nightly/std/mem/trait.TransmuteFrom.html

pub unsafe trait TransmuteFrom<Src, const ASSUME: Assume = { Assume::NOTHING }> where Src: ?Sized {}

I expected to see this happen: Renders identically to the above in the rustdoc output.

Instead, this happened: Renders as

pub unsafe trait TransmuteFrom<Src, const ASSUME: Assume = core::::mem::transmutability::TransmuteFrom::{constant#0}> where Src: ?Sized {}
Meta

rustc --version:

1.85.0-nightly (c44b3d50f 2024-12-03)

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