On Tue, Mar 19, 2019 at 3:56 AM Jakub Jelinek <ja...@redhat.com> wrote:
>
> On Mon, Mar 18, 2019 at 06:35:12PM -0600, James Hilliard wrote:
> > On Mon, Mar 18, 2019 at 5:46 PM Jeff Law <l...@redhat.com> wrote:
> > >
> > > On 3/18/19 5:07 PM, James Hilliard wrote:
> > > > On Mon, Mar 18, 2019 at 4:51 PM Jakub Jelinek <ja...@redhat.com> wrote:
> > > >>
> > > >> On Mon, Mar 18, 2019 at 04:41:05PM -0600, James Hilliard wrote:
> > > >>>> Thanks, but I'm saying that if you look at the code you can see that
> > > >>>> st is clearly initialized, by the call to lstat. I would like to see
> > > >>>> an explanation for why you are seeing that warning before changing
> > > >>>> the
> > > >>>> code to disable it. Initializing st should not be necessary here.
> > > >>>> For example, perhaps lstat is a macro when compiling libsanitizer; if
> > > >>>> that is the underlying problem, then we should fix the macro, not
> > > >>>> this
> > > >>>> code.
> > > >>> Yeah, I'm not sure why the compiler thinks lstat isn't initializing
> > > >>> st.
> > > >>> What should I do to debug this further?
> > > >>
> > > >> Guess you should start by telling us which OS it is on (I can't
> > > >> reproduce
> > > >> this warning on x86_64-linux nor i686-linux with glibc 2.28), looking
> > > >> at
> > > >> preprocessed source to see what exactly lstat does (e.g. if it is some
> > > >> macro
> > > >> or inline function and what exactly it is doing).
> > > > I am cross compiling with buildroot master branch using ubuntu 18.10.
> > > > I am building gcc 8.3.0 and glibc 2.29 for the cross toolchain.
> > > > The build and target systems are both x86_64.
> > > Add "-save-temps" to the command line. That will create a .i file, send
> > > the .i file along with the command line.
> > I added --save-temps to the cflags for the gcc package build.
> > Here's the command line log:
> > https://gist.githubusercontent.com/jameshilliard/015d972c26d1ec7bbbd1ad2d57d5dd3b/raw/7c848cdfba0967a681401de24ed6f4c86315d2d9/cli.log
> > Here's the elf.i fille:
> > https://gist.githubusercontent.com/jameshilliard/2a391d7292f3ba7412fe80e166c0f0e3/raw/63eb16ba9eff0b3ee668b16257b0948b2ca894a0/elf.i
>
> I still can't reproduce it, even with gcc 8.3.0:
> /d/gcc-8.3.0/objdir/gcc/xgcc -B /d/gcc-8.3.0/objdir/gcc/ -S -g3 -Og elf.i -W
> -Wall -Wwrite-strings -Wmissing-format-attribute -Wcast-qual -Werror
> -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition -fPIC
> -Wno-implicit-fallthrough
> doesn't print anything.
Try downloading buildroot(git commit
0af24710da70b04947229333c9450c86499b3108) and use this defconfig which
should reproduce the problem:
https://gist.github.com/jameshilliard/80e61f58e05e1325e0dbc6e30a11c851/raw/8e7d67cd1cc48f94b50e21f1ec407f29fe1dfe37/defconfig
>
> Jakub
