Prevent double frees with lexical constants

my sub foo() { 2 }

This produces a double free, because SAVEPADSVANDMORTALIZE causes the
reference count to go down on scope exit, and nothing was increment-
ing it to compensate.

1 files changed, 1 insertions, 1 deletions

diff --git a/pp.c b/pp.c
index 8e4c4a6589..e1c9d7580a 100644
--- a/pp.c
+++ b/pp.c
@@ -174,7 +174,7 @@ PP(pp_clonecv)
 	/* If this changes to use SAVECLEARSV, we can move the SAVECLEARSV
 	   to introcv and remove the SvPADSTALE_off. */
 	SAVEPADSVANDMORTALIZE(ARGTARG);
-	PAD_SVl(ARGTARG) = mg->mg_obj;
+	PAD_SVl(ARGTARG) = SvREFCNT_inc_simple_NN(mg->mg_obj);
     }
     else {
 	if (CvROOT(mg->mg_obj)) {