If I understand you right, then I compiled ode (as well as other major apps) with the following flags: export CFLAGS="-O2 -march=pentium4 -mmmx -msse -msse2 -s -pipe -Wall" export CXXFLAGS="-O2 -march=pentium4 -mmmx -msse -msse2 -s -pipe -Wall" All works fine.