diff -Nuar bareos-Release-18.2.6.org/core/src/tests/lib_tests.cc bareos-Release-18.2.6/core/src/tests/lib_tests.cc
--- bareos-Release-18.2.6.org/core/src/tests/lib_tests.cc	2019-07-13 11:14:57.946726453 +0200
+++ bareos-Release-18.2.6/core/src/tests/lib_tests.cc	2019-07-13 11:27:00.945847448 +0200
@@ -165,7 +165,7 @@
                                         const BareosVersionNumber &version_test)
 {
   char bashed_client_name[20];
-  sprintf(bashed_client_name, client_name);
+  sprintf(bashed_client_name, "%s", client_name);
   BashSpaces(bashed_client_name);
 
   char output_text[64];