Lets try defining the functions.

Author: besser82

test/getrandom-fallbacks.c

@@ -29,6 +29,23 @@
    test will not work.  */
 #if defined HAVE_ARC4RANDOM_BUF || !defined HAVE_LD_WRAP
 
+extern int __wrap_open (const char *path, int flags, mode_t mode);
+extern int __wrap_close (int fd);
+
+int
+__wrap_open (ARG_UNUSED (const char *path),
+             ARG_UNUSED (int flags),
+             ARG_UNUSED (mode_t mode))
+{
+  return -1;
+}
+
+int
+__wrap_close (ARG_UNUSED (int fd))
+{
+  return -1;
+}
+
 int
 main (void)
 {