From 701460ba84865be03df81265a6c6d76f40dd6b00 Mon Sep 17 00:00:00 2001
From: Nikita Popov <nikita.ppv@gmail.com>
Date: Sun, 24 Jun 2018 22:26:45 +0200
Subject: [PATCH] Fixed bug #76502

---
 NEWS                     |  4 ++++
 Zend/tests/bug76502.phpt | 36 ++++++++++++++++++++++++++++++++++++
 Zend/zend_exceptions.c   |  2 +-
 3 files changed, 41 insertions(+), 1 deletion(-)
 create mode 100644 Zend/tests/bug76502.phpt

diff --git a/NEWS b/NEWS
index a9218df451d..1dab097ba91 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,10 @@ PHP                                                                        NEWS
 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 ?? ??? ????, PHP 7.1.20
 
+- Core:
+  . Fixed bug #76502 (Chain of mixed exceptions and errors does not serialize
+    properly). (Nikita)
+
 - Date:
   . Fixed bug #76462 (Undefined property: DateInterval::$f). (Anatol)
 
diff --git a/Zend/tests/bug76502.phpt b/Zend/tests/bug76502.phpt
new file mode 100644
index 00000000000..caacc99f709
--- /dev/null
+++ b/Zend/tests/bug76502.phpt
@@ -0,0 +1,36 @@
+--TEST--
+Bug #76502: Chain of mixed exceptions and errors does not serialize properly
+--FILE--
+<?php
+
+$examples = [
+    "Exception(Exception())" => new Exception("outer", 0,  new Exception("inner")),
+    "Error(Error())"         => new Error("outer", 0, new Error("inner")),
+    "Error(Exception())"     => new Error("outer", 0, new Exception("inner")),
+    "Exception(Error())"     => new Exception("outer", 0, new Error("inner"))
+];
+
+foreach ($examples as $name => $example) {
+    $processed = unserialize(serialize($example));
+    $processedPrev = $processed->getPrevious();
+    echo "---- $name ----\n";
+    echo "before: ", get_class($example), ".previous == ",
+        get_class($example->getPrevious()), "\n";
+    echo "after : ", get_class($processed), ".previous == ",
+        $processedPrev ? get_class($processedPrev) : "null", "\n";
+}
+
+?>
+--EXPECT--
+---- Exception(Exception()) ----
+before: Exception.previous == Exception
+after : Exception.previous == Exception
+---- Error(Error()) ----
+before: Error.previous == Error
+after : Error.previous == Error
+---- Error(Exception()) ----
+before: Error.previous == Exception
+after : Error.previous == Exception
+---- Exception(Error()) ----
+before: Exception.previous == Error
+after : Exception.previous == Error
diff --git a/Zend/zend_exceptions.c b/Zend/zend_exceptions.c
index caa0d713725..a1d5312dbae 100644
--- a/Zend/zend_exceptions.c
+++ b/Zend/zend_exceptions.c
@@ -323,7 +323,7 @@ ZEND_METHOD(exception, __wakeup)
 	CHECK_EXC_TYPE(ZEND_STR_TRACE,    IS_ARRAY);
 	pvalue = zend_read_property(i_get_exception_base(object), object, "previous", sizeof("previous")-1, 1, &value);
 	if (pvalue && Z_TYPE_P(pvalue) != IS_NULL && (Z_TYPE_P(pvalue) != IS_OBJECT ||
-			!instanceof_function(Z_OBJCE_P(pvalue), i_get_exception_base(object)) ||
+			!instanceof_function(Z_OBJCE_P(pvalue), zend_ce_throwable) ||
 			pvalue == object)) {
 		zend_unset_property(i_get_exception_base(object), object, "previous", sizeof("previous")-1);
 	}