Re: [PATCH v5 2/3] tracing: Add a tracepoint verification check at build time

From: kernel test robot
Date: Sat Jul 26 2025 - 06:37:52 EST


Hi Steven,

kernel test robot noticed the following build warnings:

[auto build test WARNING on masahiroy-kbuild/for-next]
[also build test WARNING on masahiroy-kbuild/fixes trace/for-next arnd-asm-generic/master linus/master v6.16-rc7 next-20250725]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Steven-Rostedt/sorttable-Move-ELF-parsing-into-scripts-elf-parse-ch/20250725-105526
base: https://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git for-next
patch link: https://lore.kernel.org/r/20250725025213.342188378%40kernel.org
patch subject: [PATCH v5 2/3] tracing: Add a tracepoint verification check at build time
config: x86_64-allyesconfig (https://download.01.org/0day-ci/archive/20250726/202507261823.mtwUpXNM-lkp@xxxxxxxxx/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250726/202507261823.mtwUpXNM-lkp@xxxxxxxxx/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202507261823.mtwUpXNM-lkp@xxxxxxxxx/

All warnings (new ones prefixed by >>):

>> scripts/tracepoint-update.c:106:6: warning: variable 'count' set but not used [-Wunused-but-set-variable]
106 | int count = 0;
| ^
1 warning generated.
--
>> scripts/tracepoint-update.c:106:6: warning: variable 'count' set but not used [-Wunused-but-set-variable]
106 | int count = 0;
| ^
1 warning generated.


vim +/count +106 scripts/tracepoint-update.c

102
103 static void check_tracepoints(struct elf_tracepoint *etrace)
104 {
105 Elf_Ehdr *ehdr = etrace->ehdr;
> 106 int count = 0;
107 int len;
108
109 if (!etrace->array)
110 return;
111
112 for_each_shdr_str(len, ehdr, tracepoint_data_sec) {
113 if (!len)
114 continue;
115 if (!find_event(str, etrace->array, etrace->count)) {
116 fprintf(stderr, "warning: tracepoint '%s' is unused.\n", str);
117 }
118 count++;
119 }
120
121 free(etrace->array);
122 }
123

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki