Messages in this thread | | | Date | Fri, 22 Mar 2019 09:31:06 -0700 | From | Andi Kleen <> | Subject | Re: [PATCH 01/17] kbuild: Disable -Waddress-of-packed-member for gcc 9 |
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On Fri, Mar 22, 2019 at 02:58:51PM +0100, Arnd Bergmann wrote: > On Thu, Mar 21, 2019 at 11:00 PM Andi Kleen <andi@firstfloor.org> wrote: > > > > From: Andi Kleen <ak@linux.intel.com> > > > > This warning is very noisy in a default build with gcc 9. > > Move it into W=2 only. > > > > Cc: arnd@arndb.de > > Cc: Masahiro Yamada <yamada.masahiro@socionext.com> > > Signed-off-by: Andi Kleen <ak@linux.intel.com> > > I think W=2 is too aggressive. On many architectures, this finds > real bugs and the false positives tend to be trivial to fix > (by removing the bogus __packed annotation), which improves > the generated code in the process.
It might waste more memory or make the data structure incompatible with something external.
> > Moving it to W=1 for the moment is probably fine, but ideally > I think we should fix the kernel to behave according to the > C standard.
Okay, so is there anybody working on this?
AFAIK it's not an issue on x86 at all.
-Andi
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