← Tuesday, October 20, 2026Languages & toolsDeep dive

Rust proposal adds checked cross-crate forward declarations

lwn.net by daroc Editor score 7/10

The proposed Rust feature offers a checked alternative to C weak-symbol linking for registering functions used by standard-library code, with a possible kernel use for integer-overflow handling. It illustrates how language design can support safer systems code.

What

A Rust proposal introduces checked cross-crate forward declarations, a general mechanism for standard-library code to call user-provided functions.

How

The feature is described as a safer, checked analogue of C’s weak symbol linking.

Why it matters

The proposal includes using it to clean up how the kernel handles integer overflows in Rust code.

Read on lwn.net →

Headline, summary, brief and diagram are written by a model from the source's own text; the link, byline and numbers come from the source. Read the original before relying on a claim.