SATURDAY, JANUARY 17, 2026
gccrs
gccrs: Optionally pull in inherited arguments when required
GCC's Rust compiler can now optionally include inherited arguments during type substitution.
This change in gccrs allows for the optional inclusion of inherited arguments during type substitution. This capability is useful for correctly handling certain type-related operations, and a new test case rust/compile/gat2.rs has been added to verify its functionality.
In Details
The gccrs type substitution logic in rust-tyty-subst.cc has been updated to optionally apply inherited arguments. This refinement improves the accuracy of type substitution, particularly in scenarios involving generic associated types (GATs) or complex trait bounds, ensuring correct type resolution.
For Context
- type substitution
- The process of replacing generic type parameters with specific types or other type expressions within a type definition or in related code.
- inherited arguments
- In the context of generics and traits, these are likely type parameters passed down from an outer scope or trait definition that are needed to resolve types in an inner scope or associated type.
- generic associated types (GATs)
- A Rust feature allowing associated types within traits to themselves be generic, enabling more complex trait definitions and implementations. They are a powerful tool for abstracting over types and implementations.