https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61659
--- Comment #14 from Jason Merrill <jason at gcc dot gnu.org> --- Right. My patch causes us to synthesize ~I so that it's available for devirtualization, which we weren't doing before. This is allowed by the C++ standard: 3.2p3 says "A virtual member function is odr-used if it is not pure." so the compiler is free to instantiate/synthesize any virtual function. Avoiding this while still getting the devirtualization benefit would require some mechanism for devirtualization to call back into the front end to trigger the instantiation/synthesis directly. This might be workable for an individual translation unit, but not for LTO.
