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diag(D-W6.7): pinpoint root cause of metaclass refCount underflow #611

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fglock wants to merge 9 commits into from
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diag(D-W6.7): pinpoint root cause of metaclass refCount underflow #611

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516fef9
diag(D-W6.7): pinpoint root cause of metaclass refCount underflow
fglock Apr 29, 2026
130ebf6
test(D-W6.7): add unit tests for our %METAS storage refCount discipline
fglock Apr 29, 2026
7e1bd77
diag(D-W6.10): targeted refCount tracer + accounting confirms underflow
fglock Apr 29, 2026
3f5d10c
diag(D-W6.11/12): per-scalar ownership tracker isolates 2 unpaired incs
fglock Apr 29, 2026
bbad63d
diag(D-W6.13): activeOwners infrastructure + audit of direct --refCount
fglock Apr 29, 2026
5f2c0e8
diag(D-W6.14/15): isScalarReachable + reachableOwnerCount infrastructure
fglock Apr 29, 2026
65cadf7
diag(D-W6.16): isScalarReachable improvements + key insight on JVM GC
fglock Apr 29, 2026
c5c5417
diag(D-W6.17): plan revision — FREETMPS-style flush is necessary but …
fglock Apr 29, 2026
ee0df92
fix(D-W6.18): replace class-name heuristic with property-based walker…
fglock Apr 29, 2026
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102 changes: 102 additions & 0 deletions dev/diagnostic-traces/cmop-metaclass-refcount-underflow.txt
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Original file line number Diff line number Diff line change
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[REFCOUNT] *** ARMED *** base=573487274 (RuntimeHash) bless='Class::MOP::Class' refCount=0
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 1 -> 2 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 2 -> 1 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 1 -> 2 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 2 -> 3 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 4 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 3 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 2 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 2 -> 3 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 4 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 6 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 6 -> 7 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 7 -> 6 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 6 -> 5 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 3 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 2 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 2 -> 3 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 2 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 2 -> 3 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 4 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 6 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 6 -> 5 WeakRefRegistry.weaken (decrement on weakening)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 6 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 6 -> 5 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 3 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 4 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 6 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 3 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 4 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 7 -> 6 WeakRefRegistry.weaken (decrement on weakening)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 6 -> 5 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 6 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 6 -> 7 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 7 -> 6 WeakRefRegistry.weaken (decrement on weakening)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 6 -> 5 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 6 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 6 -> 5 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 6 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 6 -> 7 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 7 -> 6 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 6 -> 5 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 3 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 2 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 2 -> 1 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 1 -> 2 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 2 -> 3 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 4 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 WeakRefRegistry.weaken (decrement on weakening)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 3 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 2 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 2 -> 3 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 4 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 3 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 2 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 2 -> 3 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 4 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 6 -> 5 WeakRefRegistry.weaken (decrement on weakening)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 3 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 4 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 6 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 6 -> 5 WeakRefRegistry.weaken (decrement on weakening)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 5 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 6 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 6 -> 5 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 5 -> 4 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 4 -> 3 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 3 -> 2 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 2 -> 1 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 1 -> 0 MortalList.flush (deferred decrement)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 1 -> 2 RuntimeScalar.setLargeRefCounted (increment on store)
[REFCOUNT] base=573487274 (RuntimeHash) blessId=2 2 -> 3 RuntimeScalar.setLargeRefCounted (increment on store)
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