From fdee5b4a06f183a26f897e1ea8825da3577b74fd Mon Sep 17 00:00:00 2001
From: David Mitchell <davem@iabyn.com>
Date: Mon, 5 Dec 2016 14:54:44 +0000
Subject: [PATCH] assertion failure in ... or ((0) x 0))
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Petr Pisar: Ported to 5.22.2:

commit 5aa240eab7dbaa91f98c2fee1f04b6c0b5a9b9e3
Author: David Mitchell <davem@iabyn.com>
Date:   Mon Dec 5 14:54:44 2016 +0000

    assertion failure in ... or ((0) x 0))

    [perl #130247] Perl_rpeep(OP *): Assertion `oldop' failed

    the 'x 0' optimising code in rpeep didn't expect the repeat expression
    to occur on the op_other side of an op_next chain.

Signed-off-by: Petr Písař <ppisar@redhat.com>
---
 op.c          |  4 ++--
 t/op/repeat.t | 11 ++++++++++-
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/op.c b/op.c
index e92de57..48b1130 100644
--- a/op.c
+++ b/op.c
@@ -13297,10 +13297,10 @@ Perl_rpeep(pTHX_ OP *o)
                  && kid->op_next->op_type == OP_REPEAT
                  && kid->op_next->op_private & OPpREPEAT_DOLIST
                  && (kid->op_next->op_flags & OPf_WANT) == OPf_WANT_LIST
-                 && SvIOK(kSVOP_sv) && SvIVX(kSVOP_sv) == 0)
+                 && SvIOK(kSVOP_sv) && SvIVX(kSVOP_sv) == 0
+                 && oldop)
                 {
                     o = kid->op_next; /* repeat */
-                    assert(oldop);
                     oldop->op_next = o;
                     op_free(cBINOPo->op_first);
                     op_free(cBINOPo->op_last );
diff --git a/t/op/repeat.t b/t/op/repeat.t
index 8df5241..2bd3c62 100644
--- a/t/op/repeat.t
+++ b/t/op/repeat.t
@@ -6,7 +6,7 @@ BEGIN {
 }
 
 require './test.pl';
-plan(tests => 47);
+plan(tests => 48);
 
 # compile time
 
@@ -173,3 +173,12 @@ for(($#that_array)x2) {
     $_ *= 2;
 }
 is($#that_array, 28, 'list repetition propagates lvalue cx to its lhs');
+
+# [perl #130247] Perl_rpeep(OP *): Assertion `oldop' failed
+# 
+# the 'x 0' optimising code in rpeep didn't expect the repeat expression
+# to occur on the op_other side of an op_next chain.
+# This used to give an assertion failure
+
+eval q{() = (() or ((0) x 0)); 1};
+is($@, "", "RT #130247");
-- 
2.7.4