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…s path tdd_worker_subpass_fn saves four session flags and restores them through TDD_WORKER_RETURN() at its early exits after the save, but its fall-through exit restored only tdd_subpass_active, tdd_outbound_only_active and diff_operators_active. A worker that took the seeding branch (force_diff, outbound_only and eff_iter > 0) and completed normally left delta_seeded set on its clone, which survives into the next sub-pass. The setter's condition does not change between sub-passes today, so the stale value was immediately set again, but letting force_diff or outbound_only vary per sub-pass would make the stale flag select a delta where the full relation was meant, which can under-derive. End the function with TDD_WORKER_RETURN() so the fall-through takes the same restore as those early exits. The test wraps every TDD sub-pass submitted through the test submission hook and fails if a seeding sub-pass that returned successfully changed delta_seeded on its worker, or if no seeding sub-pass ran. Its program, a transitive closure that joins reach on both columns, puts the stratum in global-read mode, the mode that sets both force_diff and outbound_only. Before the fix it observed 800 seeding sub-passes and 8 leaks, one per worker. Fixes #1977
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Summary
tdd_worker_subpass_fn's success fall-through restored three of the four saved session flags and skippeddelta_seeded. A worker that took the seeding branch (force_diff && outbound_only && eff_iter > 0) and completed normally kept the flag set on its clone into the next sub-pass. The function now ends withTDD_WORKER_RETURN(), the same restore its early exits after the save use.This is latent today. Worker clones are rebuilt at every stratum init, and the setter's condition does not change between sub-passes, so the stale value was always set again. The fix keeps it from becoming under-derivation if
force_difforoutbound_onlyever vary per sub-pass.Tests
run_delta_seeded_restore_probeintests/test_tdd_inline_workers.cwraps every TDD sub-pass submitted through the test submission hook. It fails if a successful seeding sub-pass changeddelta_seeded, or if no seeding sub-pass ran, so it cannot pass vacuously. Its program joinsreachon both columns, which puts the stratum in global-read mode, the only mode that sets bothforce_diffandoutbound_only. Before the fix it observed 800 seeding sub-passes and 8 leaks (one per worker); after the fix, none.Validation
meson test: 416 OK, 0 failed, 14 skipped.--suite tidy: 4/4 OK. uncrustify is clean on both touched files.Fixes #1977