=implementation
#if { VERSION >= 5.004 } && !defined(vnewSVpvf)
-#if defined(__GNUC__) && !defined(PERL_GCC_BRACE_GROUPS_FORBIDDEN)
+#if defined(PERL_USE_GCC_BRACE_GROUPS)
# define vnewSVpvf(pat, args) ({ SV *_sv = newSV(0); sv_vsetpvfn(_sv, (pat), strlen((pat)), (args), Null(SV**), 0, Null(bool*)); _sv; })
#else
# define vnewSVpvf(pat, args) ((PL_Sv = newSV(0)), sv_vsetpvfn(PL_Sv, (pat), strlen((pat)), (args), Null(SV**), 0, Null(bool*)), PL_Sv)