SV *sv_name = newSVpv("Carp", 0);
    warn("refbefore %d",SvREFCNT(sv_name));
    load_module(PERL_LOADMOD_NOIMPORT, sv_name, Nullsv);
    warn("refafter %d",SvREFCNT(sv_name));

##</code><code>##

refbefore 1 at ....
refafter 0 at  ....