My project is split in two packages, A and B, where B uses A. All together, there are about 100 haskell modules. Currently, there seems to be a loop somewere, that only seems to occur when working with rather large datastructures. I use trace (from Debug.Trace) to see what exactly is going on. As long as I trace functions from B, trace works as expected. However, at some point I need to trace into functions supplied by package A. In package A I have a function like this: (I have simplified the function) fA :: SomeInput -> SomeResult fA a = let x = f a in trace ("Entering fA") x (The function f is defined in package A) In package B, I have a function like this: fB :: SomeInput -> SomeResult fB a = let x = fA a in trace ( "Entering fB") x At runtime, I get the message Entering fB and then nothing more. a lot of cpu is used, but no more output. I have made some wrappers like the ones above. As long as they are in the same package, trace works fine. However, when entering a function from the other package, there is no more debug output. This is very anoying. Anyone some suggestions? Is this a bug? I use the haskell platform 12.4.0.0 on a windows 7 machine. -- View this message in context: http://haskell.1045720.n5.nabble.com/Trouble-with-Debug-Trace-when-using-a-l... Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com.