shared/c-list: reimport

git subtree pull --prefix shared/c-list git@github.com:c-util/c-list.git master --squash

shared/c-list/src/test-api.c

@@ -4,6 +4,7 @@
  * shared library. Its sole purpose is to test for symbol availability.
  */
 
+#undef NDEBUG
 #include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>