The second and third links are to crash logs with only +seh and +tid set. The output from +relay was making it incredibly difficult to move around--let alone be able to record the crash--and +relay,+seh,+tid together was enough to create enough slowdown to _time out_ the server connection after one minute of logging. +seh,+tid didn't affect performance rate at all and the crashes are similar enough where cross-referencing them with the two earlier logs should grant a result.
I regret not being able to actually get the relevant function call directly in the stack trace; it seems that on Gentoo, even with FEATURES=nostrip and debugging CFLAGS/CXXFLAGS set, the positions in hex are as much as I can get for some reason. It'll have to be up to someone else to get that information. Sorry.