Ubuntu 14, Ubuntu 16, MacOS 10.11.6 with different graphic cards
Broken: 2.77 and 2.78 RC 2
Worked: not tested
Short description of error
Freestyle omits and breaks lines for geometries with dimensions larger than ~100 blender units.
Exact steps for others to reproduce the error
.blend file attached - scale the geometry so that it's dimension exceeds ~100 blender units, freestyle lines _may_ be missing. When the geometry is scaled larger than ~100 blender units, some visible lines are not drawn or are interrupted. The effect does not always occur at the same point in the geometry, as far as I could determine, there is no rule while lines are omitted/broken.
The point were the visible lines are interrupted always corresponds to where a hidden line crosses it as seen from the camera (shown for emphasis in blue in the blend file, bug exists whether hidden lines are drawn or not). Multiple crossings with hidden lines cause a succession of drawing/not-drawing (not shown in the attached file).
To see the effect scale the geometry in the attached blend file to somewhere between 110 and 170 units then render. You may have to try different scales.
When the dimension of the geometry is below 100 blender units, freestyle lines are always drawn as expected.
The problem occurs in architecture and landscape renders where it can be important to use exact dimensions (e.g. georeferenced blend files with large structures).
Attached a simple blend file and some sample renders only differing in the dimension of the geometry (camera was not moved). While the geometry is joined in the attached blend file (to make the scaling easier) the effect also occurs with multiple independent objects.