Re: [PATCH v1] perf: Fix libjvmti.c sign compare error

From: Ian Rogers
Date: Fri Jun 06 2025 - 13:42:19 EST


On Wed, Jun 4, 2025 at 10:36 AM Yuzhuo Jing <yuzhuo@xxxxxxxxxx> wrote:
>
> Fix the compile errors when compiling with -Werror=sign-compare.
>
> This is a follow-up patch to a previous patch series for a separate
> issue. Link: https://lore.kernel.org/lkml/aC9lXhPFcs5fkHWH@x1/
>
> Signed-off-by: Yuzhuo Jing <yuzhuo@xxxxxxxxxx>

Reviewed-by: Ian Rogers <irogers@xxxxxxxxxx>

Thanks,
Ian
> ---
> tools/perf/jvmti/libjvmti.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/jvmti/libjvmti.c b/tools/perf/jvmti/libjvmti.c
> index fcca275e5bf9..82514e6532b8 100644
> --- a/tools/perf/jvmti/libjvmti.c
> +++ b/tools/perf/jvmti/libjvmti.c
> @@ -141,11 +141,11 @@ copy_class_filename(const char * class_sign, const char * file_name, char * resu
> * Assume path name is class hierarchy, this is a common practice with Java programs
> */
> if (*class_sign == 'L') {
> - int j, i = 0;
> + size_t j, i = 0;
> char *p = strrchr(class_sign, '/');
> if (p) {
> /* drop the 'L' prefix and copy up to the final '/' */
> - for (i = 0; i < (p - class_sign); i++)
> + for (i = 0; i < (size_t)(p - class_sign); i++)
> result[i] = class_sign[i+1];
> }
> /*
> --
> 2.50.0.rc1.591.g9c95f17f64-goog
>