Re: [PATCH] util: constant -1 with expression of type char and allocation failure handling

[Yunseong Kim]

Hi Namhyung,

On 6/25/24 2:00 오후, Namhyung Kim wrote:
> Hello,
> 
> On Thu, Jun 20, 2024 at 04:10:53AM +0900, Yunseong Kim wrote:
>> Hi Ian,
>>
>> On 6/20/24 4:03 오전, Ian Rogers wrote:
>>>
>>>
>>> On Wed, Jun 19, 2024, 11:39 AM <yskelg@xxxxxxxxx
>>> <mailto:yskelg@xxxxxxxxx>> wrote:
>>>
>>>     From: Yunseong Kim <yskelg@xxxxxxxxx <mailto:yskelg@xxxxxxxxx>>
>>>
>>>     This patch resolve this warning.
>>>
>>>     tools/perf/util/evsel.c:1620:9: error: result of comparison of constant
>>>     -1 with expression of type 'char' is always false
>>>      -Werror,-Wtautological-constant-out-of-range-compare
>>>      1620 |                 if (c == -1)
>>>           |                     ~ ^  ~~
>>>
>>>     Add handling on unread_unwind_spec_debug_frame().
>>>     This make caller find_proc_info() works well when the allocation
>>>     failure.
>>>
>>>     Signed-off-by: Yunseong Kim <yskelg@xxxxxxxxx <mailto:yskelg@xxxxxxxxx>>
>>>
>>>
>>>
>>> Both changes look good. Could you make them 2 commits? If so add my: 
>>
>> No problem! I'll send it right away.
>>
>> Thank you for the code review.
>>
>>> Reviewed-by: Ian Rogers <irogers@xxxxxxxxxx <mailto:irogers@xxxxxxxxxx>>
> 
> You forgot to add Ian's Reviewed-by in the next patches.
> I can add it to them this time, but please do so next time.
> 
> Thanks,
> Namhyung

Thank you Namhyung for the code review. Oops, I completely forgot about
that, I'm so sorry.

>>> Thanks, 
>>> Ian
>>>
>>>     ---
>>>      tools/perf/util/evsel.c                  | 2 +-
>>>      tools/perf/util/unwind-libunwind-local.c | 5 +++++
>>>      2 files changed, 6 insertions(+), 1 deletion(-)
>>>
>>>     diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
>>>     index 25857894c047..bc603193c477 100644
>>>     --- a/tools/perf/util/evsel.c
>>>     +++ b/tools/perf/util/evsel.c
>>>     @@ -1620,7 +1620,7 @@ static int evsel__read_group(struct evsel
>>>     *leader, int cpu_map_idx, int thread)
>>>
>>>      static bool read_until_char(struct io *io, char e)
>>>      {
>>>     -       char c;
>>>     +       int c;
>>>
>>>             do {
>>>                     c = io__get_char(io);
>>>     diff --git a/tools/perf/util/unwind-libunwind-local.c
>>>     b/tools/perf/util/unwind-libunwind-local.c
>>>     index cde267ea3e99..a424eae6d308 100644
>>>     --- a/tools/perf/util/unwind-libunwind-local.c
>>>     +++ b/tools/perf/util/unwind-libunwind-local.c
>>>     @@ -390,6 +390,11 @@ static int read_unwind_spec_debug_frame(struct
>>>     dso *dso,
>>>                             char *debuglink = malloc(PATH_MAX);
>>>                             int ret = 0;
>>>
>>>     +                       if (debuglink == NULL) {
>>>     +                               pr_err("unwind: Can't read unwind
>>>     spec debug frame.\n");
>>>     +                               return -ENOMEM;
>>>     +                       }
>>>     +
>>>                             ret = dso__read_binary_type_filename(
>>>                                     dso, DSO_BINARY_TYPE__DEBUGLINK,
>>>                                     machine->root_dir, debuglink, PATH_MAX);
>>>     -- 
>>>     2.44.0
>>>
>>
>> Warm Regards,
>> Yunseong Kim

Thank you for your hard working and for always being.

Best regards,

Yunseong Kim