https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68859
--- Comment #1 from Ryan Johnson <scovich at gmail dot com> --- (I would be happy to do some legwork on this if somebody is willing to send a few pointers by PM. I know the code in gcc/cp/init.c, particularly functions `perform_member_init` and `sort_mem_initializers` are relevant, but would need some help figuring out how to traverse trees and pick out uses of member variables from other members' initializers)
