I've been getting a segfault whenever I try to run my program with +RTS -hc (having compiled with profiling enabled). Any idea what might cause this, or how I might track it down? I am using ghc 6.0.1, and see this problem on both linux (debian testing) and macos X. On macos X the crash log looks like it's crashing in heapCensusChain. My program uses ForeignPtrs quite a bit, so my only (rather weak) theory is that perhaps the profiler is trying to look at the contents of my ForeignPtrs? In a sort of related question, is there any way I can make the heap size decrease? In my test case, the memory usage peaks pretty early, and then it keeps running for another few hours. It would be nice if it could shrink the heap again to release swap. And actually, even though according to +RTS -Sstderr my live memory usage drops, the heap size (as seen by top) keeps going up (a megabyte every second or so) until the process gets killed because it's eaten up all the swap and memory. :( I suspect the problem may be in the allocation I'm doing via ForeignPtrs, but I'm not sure how to track anything down without profiling working. Any suggestions would be appreciated. -- David Roundy http://www.abridgegame.org