--- a/demo/perfo/perfo.cpp
+++ b/demo/perfo/perfo.cpp
@@ -15,7 +15,7 @@ int maxCnt;	//global variable: count of communication tries
 
 void statKatRecv(const char strTitle[], long i, long j, clock_t t, long l) {
 	printf("-------------------------------------------\n");
-	printf(strTitle); printf("\tAverage: %.3f [ms]\n", (double)t/(double)l);
+	printf("%s", strTitle); printf("\tAverage: %.3f [ms]\n", (double)t/(double)l);
 	printf("-------------------------------------------\n");
 	printf("RECV_NO_ERR		: %.3f %ld\n", (double)i/(double)l, i);
 	printf("RECV_READING_ERR	: %.3f %ld\n", (double)j/(double)l, j);