diff --git a/tests/basic/cxx_c_link.c b/tests/basic/cxx_c_link.c
index b5cefa21509f2a31a5b93f9227e3cd0e271069f5..c8b3cfa87270cad892814abc92ceb9099a58aa3d 100644
--- a/tests/basic/cxx_c_link.c
+++ b/tests/basic/cxx_c_link.c
@@ -3,3 +3,4 @@ DONTRUN: main test file is in cxx_c_link.cpp
 */
 
 #include "__fc_alloc_axiomatic.h"
+#include "stdlib.h"
diff --git a/tests/basic/cxx_c_link.cpp b/tests/basic/cxx_c_link.cpp
index 9ab7f38b6b48c8d3a23325c67d9d2e04106747e9..1ffb0ac936bfaa12e34946602bc8a4f4cab47d82 100644
--- a/tests/basic/cxx_c_link.cpp
+++ b/tests/basic/cxx_c_link.cpp
@@ -3,3 +3,4 @@ OPT: %{dep:@PTEST_DIR@/@PTEST_NAME@.c} -print
 */
 
 #include "__fc_alloc_axiomatic.h"
+#include "stdlib.h"