This one looks unique and seems to be related to an anonymous union as a parameter. I'm not sure how that can happen.

With the latest trunk:

$ fedabipkgdiff --self-compare -a --from fc37 

Comparing the ABI of binaries between nodejs-libs-18.12.1-1.fc37.ppc64le.rpm and nodejs-libs-18.12.1-1.fc37.ppc64le.rpm:

======== comparing'libnode.so.108' to itself wrongly yielded result: ===========
  Functions changes summary: 0 Removed, 1 Changed (12 filtered out), 0 Added functions
  Variables changes summary: 0 Removed, 0 Changed, 0 Added variable

  1 function with some indirect sub-type change:

    [C] 'function void nghttp2_session_callbacks_set_send_data_callback(nghttp2_session_callbacks*, int (nghttp2_session*, __anonymous_union__2*, const uint8_t*, size_t, __anonymous_union__2*, void*)*)' at nghttp2_callbacks.c:143:1 has some indirect sub-type changes:
      parameter 2 of type 'int (nghttp2_session*, __anonymous_union__2*, const uint8_t*, size_t, __anonymous_union__2*, void*)*' has sub-type changes:
        in pointed to type 'function type int (nghttp2_session*, __anonymous_union__2*, const uint8_t*, size_t, __anonymous_union__2*, void*)':

===SELF CHECK FAILED for 'libnode.so.108'