[perl #92254, #92256] Fix SAVE_DEFSV to do refcounting

The current definition of SAVE_DEFSV doesn’t take reference count-
ing into account.  Every instance of it in the perl core is buggy
as a result.

Most are also followed by DEFSV_set, which is likewise buggy.

This commit implements SAVE_DEFSV in terms of save_gp and
SAVEGENERICSV if PERL_CORE is defined.  save_gp and SAVEGENERICSV are
what local(*_) = \$foo uses.  Changing the definition for XS code is
probably too risky this close to 5.16.  It should probably be changed
later, though.

DEFSV_set is now changed to do reference counting too.

1 files changed, 1 insertions, 4 deletions

diff --git a/pp_ctl.c b/pp_ctl.c
index 8ee4d793b0..ce349bd2fe 100644
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -5477,14 +5477,11 @@ S_run_user_filter(pTHX_ int idx, SV *buf_sv, int maxlen)
 	int count;
 
 	ENTER_with_name("call_filter_sub");
-	save_gp(PL_defgv, 0);
-	GvINTRO_off(PL_defgv);
-	SAVEGENERICSV(GvSV(PL_defgv));
+	SAVE_DEFSV;
 	SAVETMPS;
 	EXTEND(SP, 2);
 
 	DEFSV_set(upstream);
-	SvREFCNT_inc_simple_void_NN(upstream);
 	PUSHMARK(SP);
 	mPUSHi(0);
 	if (filter_state) {