tested with nothing checked out on cyclone-bootstrap
used the case:

  (force (delay (+ 1 2)))

eval.c:23791 lambda 19 - self_731184[1][0][2]

eval lambda 20 - k_73700
p ((closureN)((closureN)((closureN)k_73700 )->elts[0]))->elts[2]


(define (foldr func end lst)
lst is bad in debugger:

(gdb) p *((list)lst_73538 )
$56 = {hdr = {mark = 3221189204, grayed = 0 '\000'}, tag = -1073779712, cons_car = 0x8,
  cons_cdr = 0xbffdf7f0}

  this is lambda_706 in base.c
  so... wtf?

  (cdr exp) in wrapc seems corrupt - WTF?

  (gdb) p *((list)((list)((closureN)self_731181)->elts[0])->cons_cdr)
  $67 = {hdr = {mark = 3221189204, grayed = 0 '\000'}, tag = -1073779712, cons_car = 0x8,
    cons_cdr = 0xbffdf7f0}

    presumably the cdr is corrupt in eval-from-c as well? need to check that next