The SP3 close-out v2 commit 1bcc70392 added the slot-48 "iqn_weight_max"
name to the halt_nan path's name table at training_loop.rs:2057 but missed
the symmetric halt_grad_collapse path's table at line 2143. With
nan_flags_buf now sized 49, the halt_grad_collapse formatter would
out-of-bounds index when slot 48 fires under that path.
One-line additive fix: append the same `"iqn_weight_max"` entry (with the
same SP3 close-out v2 comment) so both name tables match the buffer size.
Wire-up audit updated to document the symmetry requirement.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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