- Magnitude overflow for -32 in cn_min_sum (clamp to 31) - Converged flag cleared prematurely in IDLE (move to INIT) - msg_cn2vn zeroing race in first iteration (bypass old_msg read) All 20 test vectors now pass bit-exact against Python model. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>