p4raw-id: //depot/perl@16819
avoid incrementing the object refcount.
Note we cannot do this to avoid self-tie loops as intervening RV must
have its REFCNT incremented to keep it in existence - instead special
- case them in sv_free().
+ case them in mg_free().
*/
if (!obj || obj == sv ||
how == PERL_MAGIC_arylen ||