Re: [PATCH v3 0/8] tools: fix compilation failure caused by init_disassemble_info API changes

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Sun, Jul 31, 2022 at 06:38:26PM -0700, Andres Freund escreveu:
> binutils changed the signature of init_disassemble_info(), which now causes
> compilation failures for tools/{perf,bpf} on e.g. debian unstable. Relevant
> binutils commit:
> https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=60a3da00bd5407f07
> 
> I first fixed this without introducing the compat header, as suggested by
> Quentin, but I thought the amount of repeated boilerplate was a bit too
> much. So instead I introduced a compat header to wrap the API changes. Even
> tools/bpf/bpftool/jit_disasm.c, which needs its own callbacks for json, imo
> looks nicer this way.
> 
> I'm not regular contributor, so it very well might be my procedures are a
> bit off...
> 
> I am not sure I added the right [number of] people to CC?

I think its ok
 
> WRT the feature test: Not sure what the point of the -DPACKAGE='"perf"' is,

I think its related to libbfd, and it comes from a long time ago, trying
to find the cset adding that...

> nor why tools/perf/Makefile.config sets some LDFLAGS/CFLAGS that are also
> in feature/Makefile and why -ldl isn't needed in the other places. But...
> 
> V2:
> - split patches further, so that tools/bpf and tools/perf part are entirely
>   separate

Cool, thanks, I'll process the first 4 patches, then at some point the
bpftool bits can be merged, alternatively I can process those as well if
the bpftool maintainers are ok with it.

I'll just wait a bit to see if Jiri and others have something to say.

- Arnaldo

> - included a bit more information about tests I did in commit messages
> - add a maybe_unused to fprintf_json_styled's style argument
> 
> V3:
> - don't include dis-asm-compat.h when building without libbfd
>   (Ben Hutchings)
> - don't include compiler.h in dis-asm-compat.h, use (void) casts instead,
>   to avoid compiler.h include due to potential licensing conflict
> - dual-license dis-asm-compat.h, for better compatibility with the rest of
>   bpftool's code (suggested by Quentin Monnet)
> - don't display feature-disassembler-init-styled test
>   (suggested by Jiri Olsa)
> - don't display feature-disassembler-four-args test, I split this for the
>   different subsystems, but maybe that's overkill? (suggested by Jiri Olsa)
> 
> Cc: Alexei Starovoitov <ast@kernel.org>
> Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
> Cc: Jiri Olsa <jolsa@kernel.org>
> Cc: Sedat Dilek <sedat.dilek@gmail.com>
> Cc: Quentin Monnet <quentin@isovalent.com>
> CC: Ben Hutchings <benh@debian.org>
> Cc: bpf@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Link: https://lore.kernel.org/lkml/20220622181918.ykrs5rsnmx3og4sv@alap3.anarazel.de
> Link: https://lore.kernel.org/lkml/CA+icZUVpr8ZeOKCj4zMMqbFT013KJz2T1csvXg+VSkdvJH1Ubw@mail.gmail.com
> 
> Andres Freund (8):
>   tools build: Add feature test for init_disassemble_info API changes
>   tools build: Don't display disassembler-four-args feature test
>   tools include: add dis-asm-compat.h to handle version differences
>   tools perf: Fix compilation error with new binutils
>   tools bpf_jit_disasm: Fix compilation error with new binutils
>   tools bpf_jit_disasm: Don't display disassembler-four-args feature
>     test
>   tools bpftool: Fix compilation error with new binutils
>   tools bpftool: Don't display disassembler-four-args feature test
> 
>  tools/bpf/Makefile                            |  7 ++-
>  tools/bpf/bpf_jit_disasm.c                    |  5 +-
>  tools/bpf/bpftool/Makefile                    |  8 ++-
>  tools/bpf/bpftool/jit_disasm.c                | 42 +++++++++++---
>  tools/build/Makefile.feature                  |  4 +-
>  tools/build/feature/Makefile                  |  4 ++
>  tools/build/feature/test-all.c                |  4 ++
>  .../feature/test-disassembler-init-styled.c   | 13 +++++
>  tools/include/tools/dis-asm-compat.h          | 55 +++++++++++++++++++
>  tools/perf/Makefile.config                    |  8 +++
>  tools/perf/util/annotate.c                    |  7 ++-
>  11 files changed, 138 insertions(+), 19 deletions(-)
>  create mode 100644 tools/build/feature/test-disassembler-init-styled.c
>  create mode 100644 tools/include/tools/dis-asm-compat.h
> 
> -- 
> 2.37.0.3.g30cc8d0f14

-- 

- Arnaldo