Make &xsub and goto &xsub work with tied @_

This is the only place where tied @_ does not work, and there appears
to be no reason why it shouldn’t, apart from the fact that it hasn’t
been implemented.

Commit 67955e0c was what made &xsub work to begin with.  93965878572
introduced tied arrays and added the comment to pp_entersub saying
that @_ is not tiable.

goto &xsub has worked since perl 5.000, but 93965878572 did not make
it work with tied arrays.

diff --git a/pp_ctl.c b/pp_ctl.c
index 243bcac..bab301e 100644 (file)
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -2895,7 +2895,8 @@ PP(pp_goto) /* also pp_dump */
                OP* const retop = cx->blk_sub.retop;
                SV **newsp;
                I32 gimme;
-               const SSize_t items = arg ? AvFILLp(arg) + 1 : 0;
+               const SSize_t items = arg ? AvFILL(arg) + 1 : 0;
+               const bool m = arg ? SvRMAGICAL(arg) : 0;
                SV** mark;
 
                 PERL_UNUSED_VAR(newsp);
@@ -2904,20 +2905,25 @@ PP(pp_goto) /* also pp_dump */
                /* put GvAV(defgv) back onto stack */
                if (items) {
                    EXTEND(SP, items+1); /* @_ could have been extended. */
-                   Copy(AvARRAY(arg), SP + 1, items, SV*);
                }
                mark = SP;
-               SP += items;
-               if (items && AvREAL(arg)) {
+               if (items) {
                    SSize_t index;
+                   bool r = cBOOL(AvREAL(arg));
                    for (index=0; index<items; index++)
-                       if (SP[-index])
-                           SvREFCNT_inc_void_NN(sv_2mortal(SP[-index]));
-                       else {
-                           SP[-index] = sv_2mortal(newSVavdefelem(arg,
-                                                AvFILLp(arg) - index, 1));
+                   {
+                       SV *sv;
+                       if (m) {
+                           SV ** const svp = av_fetch(arg, index, 0);
+                           sv = svp ? *svp : NULL;
                        }
+                       else sv = AvARRAY(arg)[index];
+                       SP[index+1] = sv
+                           ? r ? SvREFCNT_inc_NN(sv_2mortal(sv)) : sv
+                           : sv_2mortal(newSVavdefelem(arg, index, 1));
+                   }
                }
+               SP += items;
                SvREFCNT_dec(arg);
                if (CxTYPE(cx) == CXt_SUB && CxHASARGS(cx)) {
                    /* Restore old @_ */

diff --git a/pp_hot.c b/pp_hot.c
index 9641b19..1155328 100644 (file)
--- a/pp_hot.c
+++ b/pp_hot.c
@@ -2715,17 +2715,26 @@ try_autoload:
             * switch stack to @_, and copy return values
             * back. This would allow popping @_ in XSUB, e.g.. XXXX */
            AV * const av = GvAV(PL_defgv);
-           const SSize_t items = AvFILLp(av) + 1;  /* @_ is not tieable */
+           const SSize_t items = AvFILL(av) + 1;
 
            if (items) {
                SSize_t i = 0;
+               const bool m = cBOOL(SvRMAGICAL(av));
                /* Mark is at the end of the stack. */
                EXTEND(SP, items);
                for (; i < items; ++i)
-                   if (AvARRAY(av)[i]) SP[i+1] = AvARRAY(av)[i];
+               {
+                   SV *sv;
+                   if (m) {
+                       SV ** const svp = av_fetch(av, i, 0);
+                       sv = svp ? *svp : NULL;
+                   }
+                   else sv = AvARRAY(av)[i];
+                   if (sv) SP[i+1] = sv;
                    else {
                        SP[i+1] = newSVavdefelem(av, i, 1);
                    }
+               }
                SP += items;
                PUTBACK ;               
            }

diff --git a/t/op/tie.t b/t/op/tie.t
index eb53030..06a39c4 100644 (file)
--- a/t/op/tie.t
+++ b/t/op/tie.t
@@ -1404,3 +1404,21 @@ print "ok\n" if (eval{ $h{foo} = 1 }||$@) eq (eval{ $h{bar} = 1 }||$@);
 EXPECT
 main
 ok
+########
+
+# &xsub and goto &xsub with tied @_
+use Tie::Array;
+tie @_, Tie::StdArray;
+@_ = "\xff";
+&utf8::encode;
+printf "%x\n", $_ for map ord, split //, $_[0];
+print "--\n";
+@_ = "\xff";
+& {sub { goto &utf8::encode }};
+printf "%x\n", $_ for map ord, split //, $_[0];
+EXPECT
+c3
+bf
+--
+c3
+bf