clang-18.1.3 on Ubuntu 24.04.2 reports warning:

  memcpy_thread.c:30:1: warning: non-void function does not return a value in all control paths [-Wreturn-type]
     30 | }
        | ^

Dismiss the warning with returning NULL from the thread function.

Signed-off-by: Leo Yan <leo.yan@arm.com>
---
 tools/perf/tests/shell/coresight/memcpy_thread/memcpy_thread.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tools/perf/tests/shell/coresight/memcpy_thread/memcpy_thread.c b/tools/perf/tests/shell/coresight/memcpy_thread/memcpy_thread.c
index 5f886cd09e6b3a62b5690dade94f1f8cae3279d2..7e879217be30a86431989dbf1f36d2134ef259cc 100644
--- a/tools/perf/tests/shell/coresight/memcpy_thread/memcpy_thread.c
+++ b/tools/perf/tests/shell/coresight/memcpy_thread/memcpy_thread.c
@@ -27,6 +27,8 @@ static void *thrfn(void *arg)
 	}
 	for (i = 0; i < len; i++)
 		memcpy(dst, src, a->size * 1024);
+
+	return NULL;
 }
 
 static pthread_t new_thr(void *(*fn) (void *arg), void *arg)

-- 
2.34.1