profiling crashes my code

Simon Peyton-Jones
Thu, 2 May 2002 00:47:04 -0700

| Okay, I've only just toyed with profiling myself, but one=20
| observation I've made is that it's not a good idea to mix=20
| modules compiled with profiling and modules compiled without.=20
| That is, always 'make clean' (i.e. 'rm -f *.o *.hi') before=20
| you build with a new set of options.

Absolutely.  GHC should complain if you mix profiled and
non-profiled code but it currently doesn't.  You'll certainly
get disaster if you mix them.  (The format of heap objects

I bet that's your problem.