https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65782
--- Comment #8 from Kai Tietz <ktietz at gcc dot gnu.org> --- Hmm, that behavior of gcc seems to be indeed pretty bad. The SEH commands for registers above index 15 (0..15) for xmm? are indeed undefined, and even worse, can't be coded proper into the seh table correctly. Anything above 16-byte size of ?mm registers, and anything above register index 15 has to be treated as call clobbered. But in anycase, the unwind information has not to contain that information
