Invalid object in isRetainer() or Segfault

When compiling with -rtsopts -threaded -prof -fprof-auto -caf-all

and running with -N4 -hr

I get a "Segmentation fault" every time.

If I run with -N4 -qg1 -hr, I either get a segfault or internal error: Invalid object in isRetainer(): 40

When the segfault happens, it happens quickly. If the segfault doesn't happen, the program runs for about 5 seconds and I get "invalid object" error (always 40).

Without -hr, I have never gotten a segfault.

Edit (1/2015): This is still occurring under multiple threads in ghc 7.8.3. GHC options: -Wall -prof -fprof-auto -threaded -rtsopts Runtime Options: -N4 -hr -L1000