[Haskell-beginners] implicit deletion of ghci history

This may sound like a strange question, but are there any commands or activities in ghc / ghci / cabal that implicitly delete your ghci history? A few times in the last few days I've started ghci, to find I only had about five or ten commands in my history, even though I execute dozens of commands each day. However, if I quickly close and reopen ghci, the commands that I just entered are still there. I can't think of anything unique to my system that would cause this, unless maybe Emacs is doing something weird with it in Haskell mode. I'm running Gentoo Linux (amd64) with GHC 7.4.1 and cabal-install 1.16.0.2. -- frigidcode.com