depends on your goals man
when i was an endurance athlete i would do my running first
when i was a competitive weight lifter i would do my weights first
you want your body fresh for what your main goal is
also packing in too much of each in the same workout is overtraining and counter productive. destroying your legs with 20 sets of squats and then doing a 10 mile run is not only stupid, but completely unnecessary and a great way to end up with leg injuries