Guard msg_id() against UninitializedMemory + add cross-process grow test - #256
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griffinmilsap merged 1 commit intoAug 10, 2026
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On top of #254: the two MessageMarshal.msg_id() call sites in the resize path (repopulate loop and the buffer-id check) can hit a slot that is uninitialized after a mid-stream resize. msg_id() calls _assert_initialized() and raises UninitializedMemory there, which would escape the receive loop and kill the channel task -- the exact failure #254 is closing. Guard both sites: treat uninitialized as skip/mismatch (drop + release backpressure). Add tests/test_shm_grow.py: a parametrized real cross-process pub/sub with small buf_size and mid-stream oversized messages (single grow, two successive grows, grow-on-first-message), asserting every message is delivered. Complements the existing shm_resize_race_runner repro. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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On top of #254: the two MessageMarshal.msg_id() call sites in the resize path (repopulate loop and the buffer-id check) can hit a slot that is uninitialized after a mid-stream resize. msg_id() calls _assert_initialized() and raises UninitializedMemory there, which would escape the receive loop and kill the channel task -- the exact failure #254 is closing. Guard both sites: treat uninitialized as skip/mismatch (drop + release backpressure).
Add tests/test_shm_grow.py: a parametrized real cross-process pub/sub with small buf_size and mid-stream oversized messages (single grow, two successive grows, grow-on-first-message), asserting every message is delivered. Complements the existing shm_resize_race_runner repro.