---
id: "bug-1806"
status: "wontfix"
status_updated: "2026-09-24"
status_note: "accepted Meson limitation (user decision 2026-09-14)"
component: "harness"
severity: "unknown"
timestamp: "2026-09-14T09:20:27.103747+00:00"
last_seen: "2026-09-19T09:00:00Z"
occurrences: 1
files: ["src/harness/meson.build", "src/tools/xce-build.sh"]
tags: ["meson", "test-runner", "build-dependency", "xce-harness-component", "accepted-limitation"]
related: ["bug-1805"]
legacy: true
---

# bug-1806: xce-harness-component task 4.3: /xce-build controller alone still rebuilds harness/xce_test on…

## Description
xce-harness-component task 4.3: /xce-build controller alone still rebuilds harness/xce_test on disk under the default asan profile, apparently violating requirement 2.2 (controller-only build shall not produce xce_test as a side effect)

## Environment
_Not recorded (migrated from buglog.json)._

## Reproduction
_Not recorded (migrated from buglog.json)._

## Root cause
Deterministic, not a flake -- confirmed via build-log line analysis. meson test (run by /xce-build controller's default RUN_TESTS=1 asan profile via meson test --suite controller) rebuilds every registered test()'s build-order dependencies PROJECT-WIDE before filtering which tests actually RUN by --suite. harness_unit_test's test() registration (src/harness/meson.build) has depends: [xce_test] (added task 2.1, verified load-bearing in task 4.2), so any meson test invocation -- even one scoped to --suite controller -- transitively relinks xce_test. The explicit  step is clean (never references xce_test); only the SUBSEQUENT meson test step touches it. Task 3.1's own validation missed this because it checked for the OLD path (controller/xce_test, correctly absent) rather than the NEW path (harness/xce_test, which does get rebuilt).

## Fix
NOT FIXED -- accepted as a documented Meson platform limitation (user decision 2026-09-14). Requirement 2.2 narrowed to scope the build system's guarantee to what it directly controls: the explicit compile-target list never names xce_test (still true and verified). Rejected alternatives: (a) add --no-rebuild to xce-build.sh's meson test calls -- non-trivial, since controller's OWN test suite already has 4 small standalone test binaries (sched_push_unit_test, sched_worker_change_unit_test, apiserver_push_unit_test, host_runusage_unit_test) not in its explicit compile target list, relying on this same auto-rebuild; fixing this properly means auditing and completing every component's explicit target list, with real regression risk; (b) restructure harness_unit_test's pty-spawning tests to drop the depends: edge and locate xce_test at runtime instead -- directly reverses the build-order guarantee task 4.2 just verified is real and load-bearing, reintroducing the stale/missing-binary risk it was added to prevent. requirements.md/design.md/tasks.md updated to reflect the narrowed, accurate guarantee.

## Verification
_Not recorded (migrated from buglog.json)._

## References
- Related: bug-1805