Files
ConformalLabpp/doc/reviewer
Tarik Moussa 5d26e5ebca ci: re-enable CGAL tests with LOW_MEMORY_BUILD for Raspberry Pi runner
Finding-I from doc/reviewer/external-audit-2026-05-30.md.

Root cause: CGAL+Eigen at -O3 drives cc1plus peak RAM to ~700 MB per
Unity compilation unit (batch size 4) on ARM64.  With the 1600 MB
container limit the 2nd or 3rd TU reliably triggered OOM-kill, so
test-cgal was gated off via `if: false` since 2026-05-26.

Fix: new CMake option CONFORMALLAB_LOW_MEMORY_BUILD=ON applies four
orthogonal memory-saving measures to conformallab_cgal_tests:

  1. -O0 (no debug info): optimizer passes entirely skipped → cc1plus
     peak drops from ~700 MB to ~150-200 MB per TU on ARM64.
     Omitting -g avoids the additional object-file / linker RAM cost.

  2. CONFORMALLAB_USE_PCH=OFF: saves the one-time ~200 MB PCH
     compilation cost; each TU re-parses CGAL headers (fast at -O0).

  3. UNITY_BUILD_BATCH_SIZE=1: one source file per cc1plus invocation,
     removing the "4-file template-explosion" per-unit multiplier.

  4. -Wl,--no-keep-memory (GNU ld): linker releases symbol tables after
     each input file → ~15-25 % less linker RSS.

Verified locally with cmake -DCONFORMALLAB_LOW_MEMORY_BUILD=ON:
  277/277 CGAL tests pass, 31 s runtime (vs 2 s at -O3 — expected;
  tests run 15× slower without optimizer but all correct).

CI workflow changes (cpp-tests.yml):
  - test-cgal re-enabled: `if: github.event_name == 'pull_request'`
  - Configure step adds -DCONFORMALLAB_LOW_MEMORY_BUILD=ON
  - Container memory: 1600m → 2000m (--memory-swap=3000m for 1 GB swap
    headroom), using ~half of the Pi's 3-4 GB while leaving OS margin.

CLAUDE.md updated: new flag added to compile-time options table; CI
status row corrected from DISABLED to active.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-05-31 00:57:28 +02:00
..

Reviewer meeting materials

A single landing page for the three documents associated with an external-reviewer meeting. The materials are written for a peer who actively publishes in discrete differential geometry — specifically the decorated-DCE / Penner-coordinates / hyperideal-polyhedra / canonical-tessellations research line — and who would potentially use conformallab++ as numerical infrastructure for their own future experiments.

Document Audience Purpose
briefing.md the reviewer one-page orientation: what the project is, where to look first, what we want from them
questions.md the reviewer the 5 concrete decisions we want their opinion on (skim before the meeting)
agenda.md me my own meeting playbook: timing, order, the "no" question, post-meeting memo template

After the meeting, a fourth file 2026-XX-XX-meeting-notes.md should land here too — the memo template at the bottom of agenda.md is the suggested structure.

When to send to the reviewer

  • briefing.md + questions.md: as part of the meeting-confirmation email, ~5 business days before the meeting. Subject line: "Pre-read for our conformallab++ chat (~15 min)".
  • agenda.md: never send. This is internal scaffolding.

Hub-Page durability

The reviewer hub HTML at https://tmoussa.codeberg.page/ConformalLabpp/ is published from doc/reviewer/hub.html in the repo (not from a detached preview branch). This means:

  • Merging any of the open PRs into main triggers .gitea/workflows/doxygen-pages.yml which republishes the hub alongside fresh Doxygen HTML — the reviewer URL stays live across merges with no manual intervention.
  • The hub is source-controlled, so changes are reviewable via PR like any other doc, and old versions live in git history.
  • The original Doxygen index moves to /doxygen.html whenever the hub override is active; both are reachable from the hub itself.