doio.c: Use SvREFCNT_dec_NN

The sole use of SvREFCNT_dec in doio.c is on a variable than is
never null (setdefout would fail an assertion otherwise), so
no need to check whether it is.

diff --git a/doio.c b/doio.c
index 08ed433..1cc0e41 100644 (file)
--- a/doio.c
+++ b/doio.c
@@ -908,7 +908,7 @@ Perl_nextargv(pTHX_ GV *gv)
        {
            GV * const oldout = MUTABLE_GV(av_pop(PL_argvout_stack));
            setdefout(oldout);
-           SvREFCNT_dec(oldout);
+           SvREFCNT_dec_NN(oldout);
            return NULL;
        }
        setdefout(gv_fetchpvs("STDOUT", GV_ADD|GV_NOTQUAL, SVt_PVIO));