I could reproduce the crash described in #1284 only with 32bits versions of godot.
The test scene contains a Plane collision shape, and a kinematicsbody with a Sphere collision shape.
The crash occurs into `CollisionSolverSW::solve_distance_plane()` on line 299 when `p_shape_A` is a `PlaneShapeSW` object and when `p_shape_B` is a `MotionShapeSW` object, because `int support_count;` is not initialized by default, and because `MotionShapeSW::get_supports()` does not change `support_count` once passed as referenced parameter, and if the default value of `support_count` is greater than the length of `supports[16]`.
I don't know if it is the good way to fix it because i'm not skilled ennough with the physics server inner working, but this fix prevents the crash and the test-scene seems to work correctly.
69cf996ce6