Tweaked `Process::Status.wait`

* revert `rb_last_status_set`
* renamed the new function as `rb_process_status_new`
* `rb_process_status_new` always freezes the return value
* marked `Process::Status.wait` as EXPERIMENTAL, as it has not
  been discussed totally yet.

1 files changed, 1 insertions, 1 deletions

diff --git a/io.c b/io.c
index b5553b5783..15032d72c2 100644
--- a/io.c
+++ b/io.c
@@ -6437,7 +6437,7 @@ pipe_finalize(rb_io_t *fptr, int noraise)
     }
     fptr->fd = -1;
     fptr->stdio_file = 0;
-    rb_last_status_set(fptr->pid, status, 0);
+    rb_last_status_set(status, fptr->pid);
 #else
     fptr_finalize(fptr, noraise);
 #endif