PerlIO_funcs *tab = INT2PTR(PerlIO_funcs *, SvIV(SvRV(layer)));
if (tab)
{
+ if (as && (ae == Nullch)) {
+ ae = e;
+ Perl_warn(aTHX_ "perlio: argument list not closed for layer \"%.*s\"",(int)(e - s),s);
+ }
len = (as) ? (ae-(as++)-1) : 0;
if (!PerlIO_push(f,tab,mode,as,len))
return -1;