[3d596659] Forward incompatibility:
File "filter_old.atd", line 6, characters 2-20:
Required field 'deleted_field' disappeared.
The following types are affected:
  a
  b

[099be5a3] Incompatibility in both directions:
File "filter_old.atd", line 7, characters 16-20
File "filter_new.atd", line 7, characters 16-23:
Type names 'int' and 'string' are not the same and may not be compatible.
The following types are affected:
  a
  b

