Fix bug #15893 by creating shared scalars with a refcount of 1

instead of 2 and make push and pop increase the refcount.

p4raw-id: //depot/perl@19200

diff --git a/ext/threads/shared/shared.xs b/ext/threads/shared/shared.xs
index a3f27e7..3e7916f 100644 (file)
--- a/ext/threads/shared/shared.xs
+++ b/ext/threads/shared/shared.xs
@@ -275,8 +275,10 @@ Perl_sharedsv_associate(pTHX_ SV **psv, SV *ssv, shared_sv *data)
     /* If neither of those then create a new one */
     if (!data) {
            SHARED_CONTEXT;
-           if (!ssv)
+           if (!ssv) {
                ssv = newSV(0);
+               SvREFCNT(ssv) = 0;
+           }
            data = PerlMemShared_malloc(sizeof(shared_sv));
            Zero(data,1,shared_sv);
            SHAREDSvPTR(data) = ssv;
@@ -503,7 +505,6 @@ sharedsv_elem_mg_FETCH(pTHX_ SV *sv, MAGIC *mg)
     assert ( SHAREDSvPTR(shared) );
 
     ENTER_LOCK;
-
     if (SvTYPE(SHAREDSvPTR(shared)) == SVt_PVAV) {
        assert ( mg->mg_ptr == 0 );
        SHARED_CONTEXT;
@@ -782,6 +783,7 @@ CODE:
            sharedsv_scalar_store(aTHX_ tmp, target);
            SHARED_CONTEXT;
            av_push((AV*) SHAREDSvPTR(shared), SHAREDSvPTR(target));
+           SvREFCNT_inc(SHAREDSvPTR(target));
            SHARED_RELEASE;
            SvREFCNT_dec(tmp);
        }
@@ -801,6 +803,7 @@ CODE:
            sharedsv_scalar_store(aTHX_ tmp, target);
            SHARED_CONTEXT;
            av_store((AV*) SHAREDSvPTR(shared), i - 1, SHAREDSvPTR(target));
+           SvREFCNT_inc(SHAREDSvPTR(target));
            CALLER_CONTEXT;
            SvREFCNT_dec(tmp);
        }