VipsImage *image = vips_image_new_from_file("something.jpg", "autorotate", TRUE, NULL);
and it'll flip it upright for you and remove any EXIF orientation tag. It isn't the default since it has (obviously) a large memory and cpu cost.
For simple resize and crop it's much better to use the exif tag to adjust the resize and crop parameters (the vipsthumbnail command does this).