Linkercoset

Linkercoset is a term used in software engineering to describe a conceptual model for organizing linker tasks into equivalence classes called cosets. The model draws on the mathematical notion of a coset to group relocation entries, symbols, and sections that share relocation and binding constraints, enabling unified manipulation during the link stage.

In this model, a linker maintains a set of cosets, each containing related entities. Operations include creating cosets, assigning symbols and relocations to cosets, merging cosets when constraints allow, and selecting a final layout that minimizes size and improves startup time. The aim is to improve determinism, modularity, and cross-target compatibility in large or multi-component builds.

Usage and workflow: developers or toolchains define initial cosets based on modules or libraries, label relocations to cosets, run a layout pass that solves a constrained optimization problem, and then apply the resulting layout to produce the final binary. It can be implemented as an abstraction layer within existing linkers (for example, as an extension to GNU ld or LLVM's LLD) or as a standalone linking engine.

Benefits and limitations: advantages include improved predictability of symbol addresses, easier incremental linking, and potential for cross-architecture portability. Limitations include added complexity to the linker implementation and the need for toolchain support to fully exploit the coset-based model.

See also: linker, relocation, code layout optimization, coset (group theory), binary optimization.