GCSTEPSIZE
lu_mem debt = cast(lu_mem, data) * 1024 - GCSTEPSIZE;
} while (debt > -GCSTEPSIZE && g->gcstate != GCSpause);
else luaE_setdebt(g, -GCSTEPSIZE); /* avoid being called too often */
#define GCSWEEPMAX (cast_int((GCSTEPSIZE / GCSWEEPCOST) / 4))
#if !defined(GCSTEPSIZE)