[Chicken-users] crashes during return-from-callbacks

[Daniel B. Faken]

Hi,

  I've been working on this for a few days, but can't seem to make any 
progress...
  I'm making callbacks via C_callback() into a closure created by eval'd 
code.  SOMETIMES when I return the value back to C, I get a crash in some 
subroutine called by C_do_apply() when the eval'd fn is returning...

  Its been very hard to track down what is causing this; all I can say is 
that it is affected by calls to (print) in the called-back scheme 
function.  Specifically, if I print some of the parameters I'm passing via 
C_callback().  But the function doesn't crash during the printing -- only 
after it reaches the second-to-last statement (which generates output, so 
I know it is called).  The last statement just returns the value.
  (This is after calling CHICKEN_run(C_toplevel) and after saving the 
input params via C_save()).

Any ideas?  I looked at the code in eval.scm, to no avail.. One thing I 
don't understand is which functions C_do_apply() call -- where are these 
4/5/6/7/8/../126 -parameter functions defined for functions created in 
eval'd code?  (I presume there are generic versions that just make a 
list of the N parameters and pass these lists to (apply) or something).
  I compile with debugging, with the debug-module turned on, and have also 
tried tracing, also to no avail.
  I've been using both yesterday's darcs head and the 2.106 release.

any help appreciated... I suspect its related to GC, but have no proof 
of this. :)

  Are there any secret options for debugging the compiler/evaluator? :)
  The next thing I can think of is just compiling the whole enchilada with 
-g... yikes.

thanks,
Daniel