On Fri, Sep 11, 2020 at 2:46 AM 'Nick Desaulniers' via Clang Built Linux <[email protected]> wrote: > > Hey Ian, > It was nice to meet you at Linux plumbers. You might want to take a > look at this series. It implements builds of the Linux kernel with > LTO. It would be good to get eyes on it and help review it from folks > working on this from the GCC angle. The series has some configs that > split where Clang specific changes need to be made; it might be of > interest to think about what would the similar changes be needed for > GCC. Also, congrats on your LWN article! > https://lwn.net/Articles/830300/
FYI. Some people may remember GCC LTO was posted in 2014 (and rejected by Linus). https://lore.kernel.org/linux-kbuild/[email protected]/ In my understanding, GCC LTO does not work for relocatable objects because GNU linker is agnostic about LTO. GCC LTO was implemented in the final link stage (i.e. vmlinux) by using $(CC) as a linker driver. On the other hand, Clang LTO, in this series implementation, works in the pre-mospost stage (i.e. vmlinux.o). -- Best Regards Masahiro Yamada
