On 9 May 2018 at 13:02, Warlich, Christof wrote: >> Oh wait, no .. x86-64 is the right value > > Why is that? I need the right host triplet to build the glibcs for each of the cpus being supported by my multilib-enabled (cross-)compiler. So I need to pass --host=x86_64-linux-gnu, and not --host=x86-64-linux-gnu. Where is x86-64 needed? The correct -march option is -march=x86-64 not -march=x86_64 Since the command I showed you gives you the default value of the -march flag, it shows x86-64 not x86_64.