error[E0499]: cannot borrow `scan` as mutable more than once at a time
  --> tests/ui/dca_ltdc_double_paint.rs:23:19
   |
20 |     let pixels1 = scan.paint_full();
   |                   ---- first mutable borrow occurs here
...
23 |     let pixels2 = scan.paint_full();
   |                   ^^^^ second mutable borrow occurs here
24 |     let _ = pixels1[0];
   |             ---------- first borrow later used here
