Re: [PATCH 1/2] selftests: cgroup: build error multiple outpt files

[Shuah Khan]

On 11/23/21 7:26 AM, Christian Brauner wrote:
> On Fri, Nov 19, 2021 at 05:22:20PM -0700, Shuah Khan wrote:
> > On 11/5/21 10:25 AM, Anders Roxell wrote:
> > > When building selftests/cgroup: with clang the following error are seen:
> > >
> > > clang -Wall -pthread    test_memcontrol.c cgroup_util.c ../clone3/clone3_selftests.h  -o /home/anders/.cache/tuxmake/builds/current/kselftest/cgroup/test_memcontrol
> > > clang: error: cannot specify -o when generating multiple output files
> > > make[3]: *** [../lib.mk:146: /home/anders/.cache/tuxmake/builds/current/kselftest/cgroup/test_memcontrol] Error 1
> > >
> > > Rework to add the header files to LOCAL_HDRS before including ../lib.mk,
> > > since the dependency is evaluated in '$(OUTPUT)/%:%.c $(LOCAL_HDRS)' in
> > > file lib.mk.
> > >
> > > Suggested-by: Arnd Bergmann <arnd@xxxxxxxx>
> > > Signed-off-by: Anders Roxell <anders.roxell@xxxxxxxxxx>
> > > ---
> > >    tools/testing/selftests/cgroup/Makefile | 12 +++++++-----
> > >    tools/testing/selftests/lib.mk          |  2 +-
> > >    2 files changed, 8 insertions(+), 6 deletions(-)
> > >
> > > diff --git a/tools/testing/selftests/cgroup/Makefile b/tools/testing/selftests/cgroup/Makefile
> > > index 59e222460581..745fe25fa0b9 100644
> > > --- a/tools/testing/selftests/cgroup/Makefile
> > > +++ b/tools/testing/selftests/cgroup/Makefile
> > > @@ -11,10 +11,12 @@ TEST_GEN_PROGS += test_core
> > >    TEST_GEN_PROGS += test_freezer
> > >    TEST_GEN_PROGS += test_kill
> > > +LOCAL_HDRS += $(selfdir)/clone3/clone3_selftests.h $(selfdir)/pidfd/pidfd.h
> > > +
> >
> > This looks odd to me. Why are we introducing dependencies between tests?
> > clone3 includes in cgroup? Looks odd to me.
>
> The cgroup tests need access to clone3() functionality in order to test
> CLONE_INTO_CGROUP which is more suited to be placed alongside the cgroup
> tests. There are a few other tests that include the clone3 header.

If other tests are also including this header, we could move it up under
selftests level. Might have to add include directory.

thanks,
-- Shuah