I have seen a crash when using the UPA API in the rsslFlush function, full details are below. This happened in debug with the gdb debugger.
I was using the RMDSTestClient as the client program.
I believe this is normal -- SIGPIPE is triggered when a write operation discovers that the connection is closed. RSSL disables this signal at initialization, but GDB will still stop and print it. You should be able to continue from this point (i.e. progress via the continue command), at which point the flush should report the disconnection.
If you wish to stop GDB from doing this, I believe you can disable it like so:
(gdb) handle SIGPIPE noprint
To see what GDB is doing with certain signals, call:
(gdb) info signals