How do I regenerate CMake component file lists?

Table of Contents

Every component's src/CMakeLists.txt=/=tests/CMakeLists.txt include()=s a generated =component_files.cmake instead of using file(GLOB_RECURSE ...) — see Replace GLOB_RECURSE with explicit source lists across the build. A generated file is a snapshot, not a live glob: a rebase or merge that lands new source files on components you didn't personally touch leaves your checked-out component_files.cmake stale, and the build fails with undefined-reference linker errors for the files it doesn't know about yet — indistinguishable from a real bug unless you know to check this first.

Question

How do I regenerate CMake component file lists?

Answer

  1. After any rebase or merge onto a branch that may have added or removed source files (not just your own branch's changes) — before your next build: 

    python3 projects/ores.codegen/scripts/regenerate_cmake_component_files.py --all

  2. Check what changed — if git status shows any component_files.cmake touched, that component gained/lost files upstream of your branch; commit the regenerated file(s) alongside your own changes: 

    git status --short -- '**/component_files.cmake'

  3. To check for drift without writing (e.g. as a pre-build sanity check, or to confirm nothing is stale before opening a PR) — exits non-zero if anything would change: 

    python3 projects/ores.codegen/scripts/regenerate_cmake_component_files.py --all --check
  4. Symptom if you skip this after a rebase: a linker error naming a symbol that's clearly defined somewhere in the tree (e.g. undefined reference to `ores::nats::parse_wire_format(...)`) — the .cpp defining it exists on disk, but the stale component_files.cmake from before the rebase never listed it. Re-run step 1 and rebuild.

Script

projects/ores.codegen/scripts/regenerate_cmake_component_files.py — see How do I add a new source file to a component? for how it's implemented (the ores.cmake.component.files_src=/ =files_tests codegen archetypes).

Tested by

Manually: this exact failure mode (a rebase landing ores.nats/domain/wire_codec.cpp from a concurrently-merged PR, producing undefined-reference linker errors until --all was re-run) was hit and fixed while closing Replace GLOB_RECURSE with explicit source lists across the build.

See also

Emacs 29.3 (Org mode 9.6.15)