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From:   Thomas Richter <tmricht@linux.ibm.com>
To:     linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org,
        acme@kernel.org
Cc:     svens@linux.ibm.com, gor@linux.ibm.com, sumanthk@linux.ibm.com,
        hca@linux.ibm.com, Thomas Richter <tmricht@linux.ibm.com>
Subject: [PATCH] perf/s390: Compiler error on s390 for bench/numa.c
Date:   Thu, 19 May 2022 10:55:30 +0200
Message-Id: <20220519085530.999726-1-tmricht@linux.ibm.com>
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The compilation on s390 results in this error:

 # make DEBUG=y bench/numa.o
 ...
 bench/numa.c: In function ‘__bench_numa’:
 bench/numa.c:1749:81: error: ‘%d’ directive output may be truncated
             writing between 1 and 11 bytes into a region of size between
             10 and 20 [-Werror=format-truncation=]
 1749 |        snprintf(tname, sizeof(tname), "process%d:thread%d", p, t);
                                                               ^~
 ...
 bench/numa.c:1749:64: note: directive argument in the range
                [-2147483647, 2147483646]
 ...
 #

The maximum length of the %d replacement is 11 characters because
of the negative sign.  Therefore use %u as format conversion.

Output after:
 # make  DEBUG=y bench/numa.o > /dev/null 2>&1; ll bench/numa.o
 -rw-r--r-- 1 root root 418320 May 19 09:11 bench/numa.o
 #

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
---
 tools/perf/bench/numa.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/bench/numa.c b/tools/perf/bench/numa.c
index d5289fa58a4f..ff0bfd87afbb 100644
--- a/tools/perf/bench/numa.c
+++ b/tools/perf/bench/numa.c
@@ -1746,7 +1746,7 @@ static int __bench_numa(const char *name)
 			for (t = 0; t < g->p.nr_threads; t++) {
 				memset(tname, 0, sizeof(tname));
 				td = g->threads + p*g->p.nr_threads + t;
-				snprintf(tname, sizeof(tname), "process%d:thread%d", p, t);
+				snprintf(tname, sizeof(tname), "process%u:thread%u", p, t);
 				print_res(tname, td->speed_gbs,
 					"GB/sec",	"thread-speed", "GB/sec/thread speed");
 				print_res(tname, td->system_time_ns / NSEC_PER_SEC,
-- 
2.36.1