From 316518b545904d368d703005f1622fde03349567 Mon Sep 17 00:00:00 2001
From: Father Chrysostomos <sprout@cpan.org>
Date: Fri, 21 Sep 2012 22:01:19 -0700
Subject: [PATCH] Free iterator when freeing tied hash

The current iterator was leaking when a tied hash was freed or
undefined.

Since we already have a mechanism, namely HvLAZYDEL, for freeing
HvEITER when not referenced elsewhere, we can use that.

Petr Pisar: Ported to 5.16.3.
---
 hv.c          |  3 +++
 t/op/svleak.t | 15 ++++++++++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/hv.c b/hv.c
index a031703..3c35341 100644
--- a/hv.c
+++ b/hv.c
@@ -2346,6 +2346,7 @@ Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
             if (entry) {
                 sv_setsv(key, HeSVKEY_force(entry));
                 SvREFCNT_dec(HeSVKEY(entry));       /* get rid of previous key */
+		HeSVKEY_set(entry, NULL);
             }
             else {
                 char *k;
@@ -2353,6 +2354,7 @@ Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
 
                 /* one HE per MAGICAL hash */
                 iter->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
+		HvLAZYDEL_on(hv); /* make sure entry gets freed */
                 Zero(entry, 1, HE);
                 Newxz(k, HEK_BASESIZE + sizeof(const SV *), char);
                 hek = (HEK*)k;
@@ -2369,6 +2371,7 @@ Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
             Safefree(HeKEY_hek(entry));
             del_HE(entry);
             iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
+	    HvLAZYDEL_off(hv);
             return NULL;
         }
     }
diff --git a/t/op/svleak.t b/t/op/svleak.t
index 6cfee2e..2f09af3 100644
--- a/t/op/svleak.t
+++ b/t/op/svleak.t
@@ -13,7 +13,7 @@ BEGIN {
 	or skip_all("XS::APItest not available");
 }
 
-plan tests => 22;
+plan tests => 23;
 
 # run some code N times. If the number of SVs at the end of loop N is
 # greater than (N-1)*delta at the end of loop 1, we've got a leak
@@ -163,3 +163,16 @@ leak(2,0,sub { !$^V }, '[perl #109762] version object in boolean context');
 
 # [perl #114764] Attributes leak scalars
 leak(2, 0, sub { eval 'my $x : shared' }, 'my $x :shared used to leak');
+
+# Tied hash iteration was leaking if the hash was freed before itera-
+# tion was over.
+package t {
+    sub TIEHASH { bless [] }
+    sub FIRSTKEY { 0 }
+}
+leak(2, 0, sub {
+    my $h = {};
+    tie %$h, t;
+    each %$h;
+    undef $h;
+}, 'tied hash iteration does not leak');
-- 
1.8.1.4