Comment 7 for bug 1740892

@afreiberger, thank you for the extra info!

Reading the upstream patch referred to in Bug 1739033, I see this change:

struct main_cp_cb_data {
- enum main_cp_cb_data_state state;
-
  int ringnumber;
  char *bindnetaddr;
  char *mcastaddr;

Now, that is a struct size change, which seems like it could easily be an exported symbol / API / ABI.

afaict, there would be no harm in leaving this struct member in place, but now unused, in the backported patch. The replacement, in the code, is to pass this struct member in the callers themselves, but this in turn changed the callback layout, which again might be part of the exported interface of the library.

How easy is this to reproduce? Do you have a testcase handy that I might be able to run?