addForeignPtrFinalizer - finalizers run in FIFO or LIFO order?

The doc of base-4.5:Foreign.ForeignPtr.addForeignPtrFinalizer states: "This function adds a finalizer to the given foreign object. The finalizer will run before all other finalizers for the same object which have already been registered." I do addForeignPtrFinalizer finalize1 fp addForeignPtrFinalizer finalize2 fp and let the finalizers print something when they are started. I get the output: finalizer1 finalizer2 This indicates that the newly added finalizer is run _after_ the finalizers that are already registered. Is this a documentation bug or a bug in the base library?