fix(build): Point3->Point conversion for wipe-loop angle detection in GCode.cpp

src/libslic3r/GCode.cpp

@@ -10554,8 +10554,8 @@ std::string GCode::extrude_loop(ExtrusionLoop loop, std::string description, dou
         // the side depends on the original winding order of the polygon (inwards for contours, outwards for holes)
         //FIXME improve the algorithm in case the loop is tiny.
         //FIXME improve the algorithm in case the loop is split into segments with a low number of points (see the Point b query).
-        Point a = paths.front().polyline.points[1];  // second point
-        Point b = *(paths.back().polyline.points.end()-3);       // second to last point
+        Point a = paths.front().polyline.points[1].to_point();  // second point
+        Point b = (paths.back().polyline.points.end()-3)->to_point();       // second to last point
         if (is_hole == loop.is_counter_clockwise()) {
             // swap points
             Point c = a; a = b; b = c;