Issues using statprof (no samples taken)

[Boris Zbarsky <bzbarsky@MIT.EDU>]

I'm having a bit of a problem with using statprof.  I checked it out 
from CVS (:pserver:anonymous@cvs.savannah.gnu.org:/sources/guile 
CVSROOT, guile/guile-statprof module).  I left it in the checkout tree, 
and am using GUILE_LOAD_PATH to point to the files.

I am using guile 1.6.8 on Mac OS X, installed via Macports.

A simple test program that looks like this:

  (use-modules (ice-9 statprof))
  (debug-enable 'debug)
  (trap-enable 'traps)
  (statprof-reset 0 500)
  (statprof-start)
  (something-to-profile)
  (statprof-stop)
  (statprof-display)

works just fine when run as:

   env GUILE_LOAD_PATH=/path/to/statprof guile16 -s ~/test.scm

and outputs profiling information.

However, what I really want to profile is a gnucash report.  If I add 
the relevant lines to the gnucash report (use-modules, debug-enable, 
trap-enable at toplevel, the rest around the part I actually want to 
profile), and run gnucash with the GUILE_LOAD_PATH set, then 
statprof-display errors out.  It does this because statprof-sample-count 
is 0 (so it ends up with a divide-by-0 error).

The operation I'm trying to profile in gnucash takes about 40 seconds, 
so sampling at 0.5ms as above should certainly be producing samples. 
Statprof is certainly being found, since the statprof-start calls don't 
error out.

Any ideas as to where I should look for what's going on here and why no 
samples are being taken?  Could it have something to do with the way 
guile is loaded by the gnucash binary?  Or with something the binary 
itself is doing?

Thank you in advance for any help,
Boris