sv.h - add SvREFCNT_dec_set_NULL()

and also SvREFCNT_dec_ret_NULL() which is used to implement
SvREFCNT_dec_set_NULL(). The set_NULL() macro is intended to
be used to replace code like this:

    if (sv) {
        SvREFCNT_dec_NN(sv);
        sv = NULL;
    }

The function form just facilitates it, and can be used in situations
where returning NULL after decrementing a refcount would be reduce
code complexity.

1 files changed, 8 insertions, 0 deletions

diff --git a/proto.h b/proto.h
index 5df8193a97..eedd5e36a2 100644
--- a/proto.h
+++ b/proto.h
@@ -76,6 +76,10 @@ Perl_Slab_Free(pTHX_ void *op);
 #define PERL_ARGS_ASSERT_SLAB_FREE              \
         assert(op)
 
+/* PERL_CALLCONV void
+SvREFCNT_dec_set_NULL(pTHX_ SV *sv); */
+#define PERL_ARGS_ASSERT_SVREFCNT_DEC_SET_NULL
+
 PERL_CALLCONV char *
 Perl__byte_dump_string(pTHX_ const U8 * const start, const STRLEN len, const bool format);
 #define PERL_ARGS_ASSERT__BYTE_DUMP_STRING      \
@@ -9643,6 +9647,10 @@ Perl_SvREFCNT_dec_NN(pTHX_ SV *sv);
         assert(sv)
 
 PERL_STATIC_INLINE SV *
+Perl_SvREFCNT_dec_ret_NULL(pTHX_ SV *sv);
+# define PERL_ARGS_ASSERT_SVREFCNT_DEC_RET_NULL
+
+PERL_STATIC_INLINE SV *
 Perl_SvREFCNT_inc(SV *sv);
 # define PERL_ARGS_ASSERT_SVREFCNT_INC