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Date: Wed, 20 Mar 2024 12:20:17 -0300
From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: Ian Rogers <irogers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@redhat.com>,
	Namhyung Kim <namhyung@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Jiri Olsa <jolsa@kernel.org>,
	Adrian Hunter <adrian.hunter@intel.com>,
	linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] perf: Suggest inbuilt commands for unknown command
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On Wed, Mar 20, 2024 at 08:12:56AM -0700, Ian Rogers wrote:
> Ah, the change:
> 
> -               static int done_help;
> +               int done_help;
> 
> created an uninitialized use. Compiler warning/sanitizers? Anyway,
> done_help needs hoisting out of the loop and initializing to zero, or
> being made static again (ugh).

⬢[acme@toolbox perf-tools-next]$ git diff
diff --git a/tools/perf/perf.c b/tools/perf/perf.c
index c719e6ccd9e27778..f9532b20e87cbf05 100644
--- a/tools/perf/perf.c
+++ b/tools/perf/perf.c
@@ -459,7 +459,7 @@ static int libperf_print(enum libperf_print_level level,
 
 int main(int argc, const char **argv)
 {
-       int err;
+       int err, done_help = 0;
        const char *cmd;
        char sbuf[STRERR_BUFSIZE];
 
@@ -558,8 +558,6 @@ int main(int argc, const char **argv)
        pthread__block_sigwinch();
 
        while (1) {
-               int done_help;
-
                run_argv(&argc, &argv);
 
                if (errno != ENOENT)
⬢[acme@toolbox perf-tools-next]$ perf raccord
  Fatal: Out of memory, realloc failed
⬢[acme@toolbox perf-tools-next]$

Then:

diff --git a/tools/perf/perf.c b/tools/perf/perf.c
index c719e6ccd9e27778..54f62aa6612bc290 100644
--- a/tools/perf/perf.c
+++ b/tools/perf/perf.c
@@ -558,7 +558,7 @@ int main(int argc, const char **argv)
        pthread__block_sigwinch();
 
        while (1) {
-               int done_help;
+               static int done_help;
 
                run_argv(&argc, &argv);
 
⬢[acme@toolbox perf-tools-next]$ perf raccord
  Fatal: Out of memory, realloc failed
⬢[acme@toolbox perf-tools-next]$

- Arnaldo