I hope you all not gonna kick me out, when u see this, but I have acctually no real clue about makefiles. The program is huge and Im getting lost to do the makefile, since I dont understand a few things about it..since the main file uses a class, which uses other classes and the other classes use again other or common classes. I got a lot of suggestions to add NDEBUD/DNDEBUD etc on the command line when compiling. As I said, I work with Eclipse and usually just press play. But I saw, that its possible to do something like a makefile there..and so I did that. I guess, I cant include NDEBUG etc without a makefile, right? And my makefile has only this line.. g++ -DNDEBUG *.cpp Its running. But not much faster. Is this totally wrong? And about the bindings.. I acctually need just to solve a linear system, with a triangle matrix: Hy = s, so is this fine just to do y = solve(subrange(H, 0,m, 0,m), subrange(s, 0, m),upper_tag()); or should I rather use the bindings. Then I use prod yet. So I do no crazy stuff, I guess the bindings arent necessary here. Am I right? Thanks a lot _________________________________________________________________ Invite your mail contacts to join your friends list with Windows Live Spaces. It's easy! http://spaces.live.com/spacesapi.aspx?wx_action=create&wx_url=/friends.aspx&mkt=en-us