I have encountered a weird drawing artifact on Amlogic S905x. I am drawing a line strip (GL_LINE_STRIP) with the following point coordinates (x, y):
-0.5, 0.0 0.0, 0.5 0.5, 0.0 0.0, -0.5-0.5, 0.0
We've definitely had bug reports related to line rendering rasterization precision on the Mali-400 series products in the past, so I suspect this will be a known issue. There have been many improvements to this part of the GPU in more recent Mali hardware designs.
In terms of a workaround, triangle rasterization is much more reliable so the recommended approach to avoid this is to covert each line segment into two triangles.
Kind regards, Pete