BugFix: we have two list now, so checking the links for NULL is not enough ...
BugFix: we have two list now, so checking the links for NULL is not enough ...

[r8020]

jonashaag/libfirm,MatzeB/libfirm,MatzeB/libfirm,jonashaag/libfirm,killbug2004/libfirm,davidgiven/libfirm,jonashaag/libfirm,8l/libfirm,8l/libfirm,8l/libfirm,8l/libfirm,davidgiven/libfirm,libfirm/libfirm,killbug2004/libfirm,MatzeB/libfirm,killbug2004/libfirm,MatzeB/libfirm,killbug2004/libfirm,jonashaag/libfirm,killbug2004/libfirm,8l/libfirm,jonashaag/libfirm,libfirm/libfirm,davidgiven/libfirm,libfirm/libfirm,MatzeB/libfirm,jonashaag/libfirm,davidgiven/libfirm,killbug2004/libfirm,8l/libfirm,8l/libfirm,davidgiven/libfirm,MatzeB/libfirm,davidgiven/libfirm,davidgiven/libfirm,MatzeB/libfirm,killbug2004/libfirm,libfirm/libfirm,jonashaag/libfirm,libfirm/libfirm