[radarhere]

Compiling locally, I found that #10122 introduced

  src/libImaging/Geometry.c:670:13: warning: 5 enumeration values not handled in switch: 'IMAGING_TRANSFORM_LANCZOS', 'IMAGING_TRANSFORM_BOX', 'IMAGING_TRANSFORM_HAMMING'... [-Wswitch]
    670 |     switch (filterid) {
        |             ^~~~~~~~
...
  src/libImaging/Geometry.c:670:13: note: add missing switch cases
    670 |     switch (filterid) {
        |             ^
    671 |         case IMAGING_TRANSFORM_NEAREST:
    672 |             if (im->image8) {
    673 |                 switch (im->type) {
    674 |                     case IMAGING_TYPE_UINT8:
    675 |                         return nearest_filter8;
    676 |                     case IMAGING_TYPE_I16:
    677 |                         return nearest_filter16;
    678 |                 }
    679 |             } else {
    680 |                 return nearest_filter32;
    681 |             }
    682 |             break;
    683 |         case IMAGING_TRANSFORM_BILINEAR:

This PR adds a default case to the switch.