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Any comments on this patch? > >>>> The addition LTO .notes information emitted by kernel is used by pahole >>>> in the following patch: >>>> https://lore.kernel.org/bpf/20210401025825.2254746-1-yhs@fb.com/ >>>> (dwarf_loader: check .notes section for lto build info) > >>> the above pahole patch has this define and comment: > >>> -static bool cus__merging_cu(Dwarf *dw) >>> +/* Match the define in linux:include/linux/elfnote.h */ >>> +#define LINUX_ELFNOTE_BUILD_LTO 0x101 > >>> ...and does not fit with the define and comment in this kernel patch: > >>> +#include >>> + >>> +#define LINUX_ELFNOTE_LTO_INFO 0x101 > >> Thanks, Sedat. I am aware of this. I think we can wait in pahole >> to make a change until the kernel patch is finalized and merged. >> The kernel patch may still change as we haven't get >> maintainer's comment. This will avoid unnecessary churn's >> in pahole side. > > So, I tested with clang 12 on fedora rawhide as well on fedora 33, and > I'm satisfied with the current state to release v1.21, Masahiro, have > you had the time to look at this? > > Yonghong, as we have a fallback in case the ELF note isn't available, I > think we're safe even if the notes patch merge gets delayed, right? Right. That is why I separated the notes patch from other patches. We can revisit it once the kernel patch is settled. > > - Arnaldo >