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charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <22D3CE6E-945B-43C4-A3A2-C57588B12BD0@fb.com> On Wed 2024-08-07 19:46:31, Song Liu wrote: > > > > On Aug 7, 2024, at 7:58 AM, zhang warden wrote: > > > > > >> In my GCC built, we have suffixes like ".constprop.0", ".part.0", ".isra.0", > >> and ".isra.0.cold". > > > > A fresher's eye, I met sometime when try to build a livepatch module and found some mistake caused by ".constprop.0" ".part.0" which is generated by GCC. > > > > These section with such suffixes is special and sometime the symbol st_value is quite different. What is these kind of section (or symbol) use for? > > > IIUC, constprop means const propagation. For example, function > "foo(int a, int b)" that is called as "foo(a, 10)" will be come > "foo(int a)" with a hard-coded b = 10 inside. > > .part.0 is part of the function, as the other part is inlined in > the caller. Hmm, we should not remove the suffixes like .constprop*, .part*, .isra*. They implement a special optimized variant of the function. It is not longer the original full-featured one. This is a difference against adding a suffix for a static function. Such a symbol implements the original full-featured function. Best Regards, Petr