Two bump arenas. arena_reset_trans() runs between top-level forms;
top-level define / set! deep-copy the bound value graph into perm
via Cheney-style forwarding (pin = -1 + stashed fwd pointer in
.car/.val) so no perm cell ever points into trans. Args slice in
eval's apply path also gets explicit os.free per dispatch — without
that the rt_ensure page-per-call leak dominated and masked the
reset. test_huge peaks at ~2.6 MB under massif --pages-as-heap=yes,
down from ~525 MB pre-arena (~200x).
Hojun-Cho
1c184ee6aa