https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64379
--- Comment #13 from Donn Seeley <donn.seeley at windriver dot com> --- BTW, this issue cropped up in Wind River Linux testing, not VxWorks. I have no idea whether the VxWorks folks are using -mapcs-frame. WR Linux will remove the -mapcs-frame flag from future builds; it was originally added to support patches to oprofile that we have since dropped.
