ci: coverage check failing on main since 2026-05-11 sweep (AgentCoreTest.BackpressureConcurrentTrigger)

[mvillmow]

Summary

The coverage required CI check is failing on main HEAD as of 2026-05-11. This was discovered during the ecosystem-wide easy-issue sweep when PR #552 could not auto-merge due to this failing required check.

This failure is pre-existing on main — it was NOT introduced by PR #552 — and was verified via gh api repos/HomericIntelligence/ProjectKeystone/commits/<main-sha>/check-runs.

PR #552 was merged via admin override to unblock the sweep.

Failing job

• Job ID: 75491792540
• Workflow: coverage
• Failing test: AgentCoreTest.BackpressureConcurrentTrigger (Subprocess aborted)

Excerpt from job log

The following tests FAILED:
	 76 - AgentCoreTest.BackpressureConcurrentTrigger (Subprocess aborted)
Errors while running CTest
make[3]: *** [Makefile:108: test] Error 8
make[2]: *** [Makefile:356: test.debug] Error 2
make[1]: *** [Makefile:347: test.debug.coverage] Error 2
make: *** [Makefile:364: test.debug.coverage.native] Error 2
##[error]Process completed with exit code 2.

Likely cause

The Subprocess aborted signal on a Backpressure*Concurrent* test strongly suggests a race condition / TSAN or sanitizer abort under the coverage build (which compiles with -O0 -g -DENABLE_COVERAGE=ON). May be flaky, may be a real concurrency bug exposed by the unoptimized build.

Action required

• Reproduce locally with make test.debug.coverage.native
• Determine if the failure is flaky vs. deterministic
• If flaky: stabilize or quarantine the test
• If deterministic: fix the underlying concurrency bug
• Restore coverage to a green state on main so future PRs can auto-merge