The `ABC_INLINE` macro has been in the Alembic code since it was introduced to Blender in rB61050f75b13e. It basically does the same a `BLI_INLINE`, though, so there is no need to keep it around.
The `ABC_INLINE` macro has been in the Alembic code since it was introduced to Blender in rB61050f75b13e. It basically does the same a `BLI_INLINE`, though, so there is no need to keep it around.