From 242d924e599d2c92a5d12873ad1564f7d44f7126 Mon Sep 17 00:00:00 2001
From: Nikita Popov <nikic@php.net>
Date: Sat, 31 Dec 2016 13:33:21 +0100
Subject: [PATCH] Fix bug #73847

---
 NEWS                             |  1 +
 ext/opcache/Optimizer/dfa_pass.c |  6 +++++
 ext/opcache/tests/bug73847.phpt  | 44 ++++++++++++++++++++++++++++++++
 3 files changed, 51 insertions(+)
 create mode 100644 ext/opcache/tests/bug73847.phpt

diff --git a/NEWS b/NEWS
index 9d1a2c5bc9..d06b6c4ae3 100644
--- a/NEWS
+++ b/NEWS
@@ -37,6 +37,7 @@ PHP                                                                        NEWS
   . Fixed bug #73654 (Segmentation fault in zend_call_function). (Nikita)
   . Fixed bug #73668 ("SIGFPE Arithmetic exception" in opcache when divide by
     minus 1). (Nikita)
+  . Fixed bug #73847 (Recursion when a variable is redefined as array). (Nikita)
 
 - PDO_Firebird:
   . Fixed bug #72931 (PDO_FIREBIRD with Firebird 3.0 not work on returning
diff --git a/ext/opcache/Optimizer/dfa_pass.c b/ext/opcache/Optimizer/dfa_pass.c
index 2780a4cc54..f01e2ecc65 100644
--- a/ext/opcache/Optimizer/dfa_pass.c
+++ b/ext/opcache/Optimizer/dfa_pass.c
@@ -356,6 +356,12 @@ static zend_bool opline_supports_assign_contraction(
 		return opline->op1_type != IS_CV || opline->op1.var != cv_var;
 	}
 
+	if (opline->opcode == ZEND_INIT_ARRAY) {
+		/* INIT_ARRAY initializes the result array before reading key/value. */
+		return (opline->op1_type != IS_CV || opline->op1.var != cv_var)
+			&& (opline->op2_type != IS_CV || opline->op2.var != cv_var);
+	}
+
 	return 1;
 }
 
diff --git a/ext/opcache/tests/bug73847.phpt b/ext/opcache/tests/bug73847.phpt
new file mode 100644
index 0000000000..7010dfbfb7
--- /dev/null
+++ b/ext/opcache/tests/bug73847.phpt
@@ -0,0 +1,44 @@
+--TEST--
+Bug #73847: Recursion when a variable is redefined as array
+--FILE--
+<?php
+function test() {
+    $a = 42;
+    $a = array($a);
+    var_dump($a);
+
+    $a = 42;
+    $a = array($a => 24);
+    var_dump($a);
+
+    $a = 42;
+    $a = array($a, 24);
+    var_dump($a);
+
+    $a = 42;
+    $a = array(24, $a);
+    var_dump($a);
+}
+test();
+?>
+--EXPECT--
+array(1) {
+  [0]=>
+  int(42)
+}
+array(1) {
+  [42]=>
+  int(24)
+}
+array(2) {
+  [0]=>
+  int(42)
+  [1]=>
+  int(24)
+}
+array(2) {
+  [0]=>
+  int(24)
+  [1]=>
+  int(42)
+}
-- 
2.40.0