if ( !sv_derived_from(_sv, "version") ) \
_sv = new_version(_sv); \
if ( vcmp(_sv,xssv) ) \
- Perl_croak(aTHX_ "%s object version %_ does not match %s%s%s%s %_",\
+ Perl_croak(aTHX_ "%s object version %"SVf" does not match %s%s%s%s %"SVf,\
module, vstringify(xssv), \
vn ? "$" : "", vn ? module : "", vn ? "::" : "", \
vn ? vn : "bootstrap parameter", vstringify(_sv));\