https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68507
Bug ID: 68507 Summary: attribute ms_abi (on Linux) bloats by pushing/popping xmm6-15 needlessly Product: gcc Version: 4.9.3 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: daniel.santos at pobox dot com Target Milestone: --- Created attachment 36814 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36814&action=edit simple test case When a function declared ms_abi calls a function not (and thus, implicitly sysv_abi on Linux) then the ms_abi function saves & restores xmm6-16 needlessly causing quite a lot of bloat in wine. I'm still on 4.9.3, so building (gentoo) 5.2.0 now to see if the bug is still there. When debian released the wine 1.8-rc1 today, all of the code was bloated like this too.