diff --git a/offload/test/offloading/shared_lib_fp_mapping.c b/offload/test/offloading/shared_lib_fp_mapping.c
index c6203443eee18..e0af9b70a75c5 100644
--- a/offload/test/offloading/shared_lib_fp_mapping.c
+++ b/offload/test/offloading/shared_lib_fp_mapping.c
@@ -7,8 +7,8 @@
 
 #include <stdio.h>
 
-extern int func(); // Provided in liba.so, returns 42
-typedef int (*fp_t)();
+extern int func(void); // Provided in liba.so, returns 42
+typedef int (*fp_t)(void);
 
 int main() {
   int x = 0;
diff --git a/offload/test/offloading/static_linking.c b/offload/test/offloading/static_linking.c
index 7be95a10ffcd6..273109e10c09e 100644
--- a/offload/test/offloading/static_linking.c
+++ b/offload/test/offloading/static_linking.c
@@ -14,7 +14,7 @@ int foo() {
 }
 #else
 #include <stdio.h>
-int foo();
+int foo(void);
 
 int main() {
   int x = foo();