Messages in this thread | | | Date | Mon, 22 May 2023 17:52:32 +0100 | From | Greg KH <> | Subject | Re: [PATCH v4] Makefile.compiler: replace cc-ifversion with compiler-specific macros |
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On Mon, May 22, 2023 at 12:09:34PM +0200, Ricardo Cañuelo wrote: > On vie, may 19 2023 at 08:57:24, Nick Desaulniers <ndesaulniers@google.com> wrote: > > It could be; if the link order was changed, it's possible that this > > target may be hitting something along the lines of: > > https://isocpp.org/wiki/faq/ctors#static-init-order i.e. the "static > > initialization order fiasco" > > > > I'm struggling to think of how this appears in C codebases, but I > > swear years ago I had a discussion with GKH (maybe?) about this. I > > think I was playing with converting Kbuild to use Ninja rather than > > Make; the resulting kernel image wouldn't boot because I had modified > > the order the object files were linked in. If you were to randomly > > shuffle the object files in the kernel, I recall some hazard that may > > prevent boot. > > I thought that was specifically a C++ problem? But then again, the > kernel docs explicitly say that the ordering of obj-y goals in kbuild is > significant in some instances [1]:
Yes, it matters, you can not change it. If you do, systems will break. It is the only way we have of properly ordering our init calls within the same "level".
thanks,
greg k-h
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