in src/library.c (main branch), I find:
const char* Parrot_get_runtime_prefix(Interp *interpreter, STRING **prefix_str) { static STRING *s; static int init_done; static const char *prefix; int free_env; char *env;
if (!*runtime_prefix) return NULL; if (!init_done) { /* stat()ing the top level directory doesn't work reliably as often
...
init_done is never initialized here. What's up?