Bug: ALP DOUBLE exception chunk can reach invalid state and crash during checkpoint

[ericyuanhui]

Ladybug version

main release version

What operating system are you using?

ubuntu24.04

What happened?

Problem

A separate crash was observed in:

InMemoryExceptionChunk<double>::finalizeAndFlushToDisk

The core showed an invalid ALP exception chunk / invalid internal ColumnChunkData state during checkpoint finalization.

Relevant path:

COPY / COMMIT
  -> StorageManager::checkpoint
  -> Column::checkpointSegment
  -> InMemoryExceptionChunk<double>::finalizeAndFlushToDisk
  -> SIGSEGV

The ALP exception code uses several debug-only checks:

DASSERT(exceptionCount < exceptionCapacity);
DASSERT(exceptionIdx < exceptionCount);
DASSERT(exceptionPageOffset == (page_idx_t)exceptionPageOffset);

These checks are removed in Release and RelWithDebInfo builds. If ALP metadata is inconsistent, an exception index is invalid, or the exception buffer is full, the engine may read or write outside valid memory. This can corrupt memory before the final checkpoint crash becomes visible.

Are there known steps to reproduce?

No response