Per-Library Whole-Archive Support via CMake Link Features

[MatthiasHertel80]

Summary

Add support in csolution / cbuild to mark individual static libraries in a cproject as requiring whole-archive semantics, and propagate this to the generated CMake using CMake link features (generator expressions).

Problem

When static libraries are linked normally, the linker only pulls object files that satisfy unresolved symbols. Libraries that rely on static initialization or self-registration (e.g. kernel registries, plugin-style components) break when packaged as .a files, even though they work when linked as source.

Proposed Solution

Allow a per-library attribute in cproject that requests whole-archive behavior, mapped by cbuild to CMake link features.

Example:

- group: ExecuTorch Libraries
  files:
    - file: ./engine/lib/libexecutorch_core.a
    - file: ./engine/lib/libportable_kernels.a
      attributes: [whole-archive]
    - file: ./engine/lib/libcortex_m_kernels.a
      attributes: [whole-archive]

cbuild generates CMake that applies whole-archive semantics only to the annotated libraries (equivalent to --whole-archive / --no-whole-archive).

Reference

CMake link features / generator expressions:
https://cmake.org/cmake/help/latest/manual/cmake-generator-expressions.7.html#link-features

[ReinhardKeil]

I suggest to use instead of attribute: the keyword link: to indicate that this is a linkage directive. It would then read:

  - file: my_library.a
    link: whole-archive