Re: [PATCH v2 0/5] tools: fix compilation failure caused by init_disassemble_info API changes

[Jiri Olsa <olsajiri@gmail.com>]

On Sun, Jul 03, 2022 at 02:25:46PM -0700, Andres Freund wrote:
> 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?
> 
> WRT the feature test: Not sure what the point of the -DPACKAGE='"perf"' is,
> 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
> - included a bit more information about tests I did in commit messages
> - add a maybe_unused to fprintf_json_styled's style argument
> 
> 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>
> To: bpf@vger.kernel.org
> To: 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 (5):
>   tools build: add feature test for init_disassemble_info API changes
>   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 bpftool: Fix compilation error with new binutils

I think the disassembler checks should not be displayed by default,
with your change I can see all the time:

...        disassembler-four-args: [ on  ]
...      disassembler-init-styled: [ OFF ]


could you please squash something like below in? moving disassembler
checks out of sight and do manual detection

thanks,
jirka


---
diff --git a/tools/build/Makefile.feature b/tools/build/Makefile.feature
index 339686b99a6e..bce9a9b52b2c 100644
--- a/tools/build/Makefile.feature
+++ b/tools/build/Makefile.feature
@@ -69,8 +69,6 @@ FEATURE_TESTS_BASIC :=                  \
         setns				\
         libaio				\
         libzstd				\
-        disassembler-four-args		\
-        disassembler-init-styled	\
         file-handle
 
 # FEATURE_TESTS_BASIC + FEATURE_TESTS_EXTRA is the complete list
@@ -106,7 +104,9 @@ FEATURE_TESTS_EXTRA :=                  \
          libbpf-bpf_create_map		\
          libpfm4                        \
          libdebuginfod			\
-         clang-bpf-co-re
+         clang-bpf-co-re		\
+         disassembler-four-args		\
+         disassembler-init-styled
 
 
 FEATURE_TESTS ?= $(FEATURE_TESTS_BASIC)
@@ -135,9 +135,7 @@ FEATURE_DISPLAY ?=              \
          get_cpuid              \
          bpf			\
          libaio			\
-         libzstd		\
-         disassembler-four-args	\
-         disassembler-init-styled
+         libzstd
 
 # Set FEATURE_CHECK_(C|LD)FLAGS-all for all FEATURE_TESTS features.
 # If in the future we need per-feature checks/flags for features not
diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index ee417c321adb..2aa0bad11f05 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -914,8 +914,6 @@ ifndef NO_LIBBFD
         FEATURE_CHECK_LDFLAGS-disassembler-init-styled += -liberty -lz -ldl
       endif
     endif
-    $(call feature_check,disassembler-four-args)
-    $(call feature_check,disassembler-init-styled)
   endif
 
   ifeq ($(feature-libbfd-buildid), 1)
@@ -1025,6 +1023,9 @@ ifdef HAVE_KVM_STAT_SUPPORT
     CFLAGS += -DHAVE_KVM_STAT_SUPPORT
 endif
 
+$(call feature_check,disassembler-four-args)
+$(call feature_check,disassembler-init-styled)
+
 ifeq ($(feature-disassembler-four-args), 1)
     CFLAGS += -DDISASM_FOUR_ARGS_SIGNATURE
 endif