------- Comment #2 from steven at gcc dot gnu dot org 2010-04-12 16:15 ------- For the Mach-O file format, follow this link: http://developer.apple.com/mac/library/documentation/DeveloperTools/Conceptual/MachORuntime/Reference/reference.html
First step for Mach-O support would be figuring out where to store the LTO data. AFAIU, Mach-O has segments, which are bundles of sections. I don't know if GCC LTO should write a segment, or a section. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43729
