Fix skip logic in pad_tidy and cv_clone

Commit 325e1816dc changed the logic for determining whether a pad
entry is to be treated like a constant; i.e., shared between recursion
levels and sub clones.

According the old logic, a pad entry must be shared if it is marked
READONLY or is a shared hash key scalar.  According to the new logic,
the entry must be shared if the pad name has a zero-length PV (i.e.,
&PL_sv_no).

Two pieces of code were still following the old logic.  Changing them
fixes this old bug:

my $close_over_me;
sub  {
    () = $close_over_me;
    open my $fh, "/dev/null";
    print "$$fh\n"
}->();
__END__

Output:
*main::

The name attached to the implicit rv2gv op in open() was not being
copied by sub clones.

The previous commit is also part of the fix.

In the tests, I tested the combination of sub cloning and recursion,
since it seemed like a good idea (and also as a result of copying and
pasting :-).

S_pmtrans was still relying on the old logic, so it gets changed, too.

1 files changed, 1 insertions, 1 deletions

diff --git a/op.c b/op.c
index 44d2f203fb..c5964eb88f 100644
--- a/op.c
+++ b/op.c
@@ -4268,7 +4268,7 @@ S_pmtrans(pTHX_ OP *o, OP *expr, OP *repl)
 
 	swash = MUTABLE_SV(swash_init("utf8", "", listsv, bits, none));
 #ifdef USE_ITHREADS
-	cPADOPo->op_padix = pad_alloc(OP_TRANS, SVs_PADTMP);
+	cPADOPo->op_padix = pad_alloc(OP_TRANS, SVf_READONLY);
 	SvREFCNT_dec(PAD_SVl(cPADOPo->op_padix));
 	PAD_SETSV(cPADOPo->op_padix, swash);
 	SvPADTMP_on(swash);