Re: [Linux-6.11-rc4] perf BROKEN with LLVM/Clang 19.1.0-rc3

[Arnaldo Carvalho de Melo]

On Wed, Aug 21, 2024 at 01:37:25PM -0700, Namhyung Kim wrote:
> Hello,
> 
> On Wed, Aug 21, 2024 at 12:37 PM Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote:
> >
> > As a workaround:
> >
> > dileks@iniza:~/src/linux/git$ git diff
> > diff --git a/tools/perf/util/setup.py b/tools/perf/util/setup.py
> > index 142e9d447ce7..db45e6fe7a21 100644
> > --- a/tools/perf/util/setup.py
> > +++ b/tools/perf/util/setup.py
> > @@ -63,6 +63,8 @@ cflags = getenv('CFLAGS', '').split()
> > cflags += ['-fno-strict-aliasing', '-Wno-write-strings',
> > '-Wno-unused-parameter', '-Wno-redundant-decls' ]
> > if cc_is_clang:
> >     cflags += ["-Wno-unused-command-line-argument" ]
> > +    cflags += ["-Wno-cast-function-type-mismatch" ]
> > +
> > else:
> >     cflags += ['-Wno-cast-function-type' ]
> >
> 
> Thanks for the fix.  I wasn't aware of the issue and the fix
> looks good to me.  I'll add it to perf-tools if nobody objects.

It doesn't work, please see the alternative patch I sent, if you try
that in a clang that doesn't have that warning option, it will fail,
i.e. clang 18 fails with the above patch.

- Arnaldo
 
> Thanks,
> Namhyung
> 
> 
> > dileks@iniza:~/src/linux/git$ ~/bin/perf -vv
> > perf version 6.11.0-rc4
> >                 dwarf: [ on  ]  # HAVE_DWARF_SUPPORT
> >    dwarf_getlocations: [ on  ]  # HAVE_DWARF_GETLOCATIONS_SUPPORT
> >         syscall_table: [ on  ]  # HAVE_SYSCALL_TABLE_SUPPORT
> >                libbfd: [ OFF ]  # HAVE_LIBBFD_SUPPORT
> >            debuginfod: [ on  ]  # HAVE_DEBUGINFOD_SUPPORT
> >                libelf: [ on  ]  # HAVE_LIBELF_SUPPORT
> >               libnuma: [ on  ]  # HAVE_LIBNUMA_SUPPORT
> > numa_num_possible_cpus: [ on  ]  # HAVE_LIBNUMA_SUPPORT
> >               libperl: [ on  ]  # HAVE_LIBPERL_SUPPORT
> >             libpython: [ on  ]  # HAVE_LIBPYTHON_SUPPORT
> >              libslang: [ on  ]  # HAVE_SLANG_SUPPORT
> >             libcrypto: [ on  ]  # HAVE_LIBCRYPTO_SUPPORT
> >             libunwind: [ on  ]  # HAVE_LIBUNWIND_SUPPORT
> >    libdw-dwarf-unwind: [ on  ]  # HAVE_DWARF_SUPPORT
> >           libcapstone: [ on  ]  # HAVE_LIBCAPSTONE_SUPPORT
> >                  zlib: [ on  ]  # HAVE_ZLIB_SUPPORT
> >                  lzma: [ on  ]  # HAVE_LZMA_SUPPORT
> >             get_cpuid: [ on  ]  # HAVE_AUXTRACE_SUPPORT
> >                   bpf: [ on  ]  # HAVE_LIBBPF_SUPPORT
> >                   aio: [ on  ]  # HAVE_AIO_SUPPORT
> >                  zstd: [ on  ]  # HAVE_ZSTD_SUPPORT
> >               libpfm4: [ on  ]  # HAVE_LIBPFM
> >         libtraceevent: [ on  ]  # HAVE_LIBTRACEEVENT
> >         bpf_skeletons: [ on  ]  # HAVE_BPF_SKEL
> >  dwarf-unwind-support: [ on  ]  # HAVE_DWARF_UNWIND_SUPPORT
> >            libopencsd: [ OFF ]  # HAVE_CSTRACE_SUPPORT
> >
> > -Sedat-