diff --git a/testing/ostest/barrier.c b/testing/ostest/barrier.c
index 6f4172c65..4078a69db 100644
--- a/testing/ostest/barrier.c
+++ b/testing/ostest/barrier.c
@@ -155,7 +155,7 @@ void barrier_test(void)
                               (pthread_addr_t)((uintptr_t)i));
       if (status != 0)
         {
-          printf("barrier_test: Error in thread %d create, status=%d\n",
+          printf("barrier_test: ERROR thread %d create, status=%d\n",
                  i, status);
           printf("barrier_test: Test aborted with waiting threads\n");
           goto abort_test;
@@ -174,7 +174,7 @@ void barrier_test(void)
       status = pthread_join(barrier_thread[i], &result);
       if (status != 0)
         {
-          printf("barrier_test: Error in thread %d join, status=%d\n",
+          printf("barrier_test: ERROR thread %d join, status=%d\n",
                  i, status);
         }
       else
diff --git a/testing/ostest/mutex.c b/testing/ostest/mutex.c
index 7820848cc..92ca372e2 100644
--- a/testing/ostest/mutex.c
+++ b/testing/ostest/mutex.c
@@ -137,7 +137,7 @@ void mutex_test(void)
 #endif
   if (status != 0)
     {
-      printf("Error in thread#1 creation\n");
+      printf("ERROR in thread#1 creation\n");
     }
 
   printf("Starting thread 2\n");
@@ -148,7 +148,7 @@ void mutex_test(void)
 #endif
   if (status != 0)
     {
-      printf("Error in thread#2 creation\n");
+      printf("ERROR in thread#2 creation\n");
     }
 
 #ifdef SDCC
diff --git a/testing/ostest/ostest_main.c b/testing/ostest/ostest_main.c
index 36770525f..ecf57433c 100644
--- a/testing/ostest/ostest_main.c
+++ b/testing/ostest/ostest_main.c
@@ -225,7 +225,7 @@ static int user_main(int argc, char *argv[])
 
   if (argc != NARGS + 1)
     {
-      printf("user_main: Error expected argc=%d got argc=%d\n",
+      printf("user_main: ERROR expected argc=%d got argc=%d\n",
              NARGS + 1, argc);
     }
 
diff --git a/testing/ostest/timedmutex.c b/testing/ostest/timedmutex.c
index 41088487d..cd1c6ed53 100644
--- a/testing/ostest/timedmutex.c
+++ b/testing/ostest/timedmutex.c
@@ -164,7 +164,7 @@ void timedmutex_test(void)
 #endif
   if (status != 0)
     {
-      fprintf(stderr, "mutex_test: Error in thread creation: %d\n", status);
+      fprintf(stderr, "mutex_test: ERROR in thread creation: %d\n", status);
       goto errout_with_lock;
     }