I tried to write a program using Text.Regex.PCRE to search through a UTF8-encoded document. It appears that the presence of non-breaking-space characters (code point 160) triggers some weird behavior in my program. This is using the Debian stable(Jessie) packages of ghc 7.6.3 and libraries. Now I find myself at a fork in the road, not sure which direction to head in. Do I: 1) Continue looking (or get help with looking) for bugs in my code? (I have this reduced to a pretty small test case) 2) Assemble a bug-report against debian? 3) Assemble a bug-report against Text.Regex.PCRE (or Text.Regex.Base) for "upstream" 4) Uninstall Text.Regex.PCRE (and/or some other packages) and switch to something that works with Unicode/UTF8? Any ideas?