parse.y:5541
static int
local_append(id)
    ID id;
{
    if (lvtbl->tbl == 0) {
	lvtbl->tbl = ALLOC_N(ID, 4);
	lvtbl->tbl[0] = 0;
	lvtbl->tbl[1] = '_';
	lvtbl->tbl[2] = '~';
	lvtbl->cnt = 2;
	if (id == '_') return 0;
	if (id == '~') return 1;
    }
    else {
	REALLOC_N(lvtbl->tbl, ID, lvtbl->cnt+2);
    }

    lvtbl->tbl[lvtbl->cnt+1] = id;
    return lvtbl->cnt++;
}
