From f70b552326e5242655d6ac2c55ca220e89afef34 Mon Sep 17 00:00:00 2001
From: Nikita Popov <nikita.ppv@gmail.com>
Date: Thu, 30 Jan 2020 14:55:58 +0100
Subject: [PATCH] Fixed bug #79193

---
 NEWS                                   |  2 ++
 ext/opcache/Optimizer/zend_inference.c |  7 +++++++
 ext/opcache/tests/bug79193.phpt        | 18 ++++++++++++++++++
 3 files changed, 27 insertions(+)
 create mode 100644 ext/opcache/tests/bug79193.phpt

diff --git a/NEWS b/NEWS
index 2dcfdf9db3..a4ef1ef469 100644
--- a/NEWS
+++ b/NEWS
@@ -39,6 +39,8 @@ PHP                                                                        NEWS
   . Fixed bug #79114 (Eval class during preload causes class to be only half
     available). (Laruence)
   . Fixed bug #79128 (Preloading segfaults if preload_user is used). (Nikita)
+  . Fixed bug #79193 (Incorrect type inference for self::$field =& $field).
+    (Nikita)
 
 - OpenSSL:
   . Fixed bug #79145 (openssl memory leak). (cmb, Nikita)
diff --git a/ext/opcache/Optimizer/zend_inference.c b/ext/opcache/Optimizer/zend_inference.c
index f89b133b92..7accf73a5d 100644
--- a/ext/opcache/Optimizer/zend_inference.c
+++ b/ext/opcache/Optimizer/zend_inference.c
@@ -2999,6 +2999,13 @@ static int zend_update_type_info(const zend_op_array *op_array,
 				UPDATE_SSA_TYPE(tmp, ssa_ops[i].op1_def);
 			}
 			break;
+		case ZEND_ASSIGN_STATIC_PROP_REF:
+			if ((opline+1)->op1_type == IS_CV) {
+				opline++;
+				i++;
+				UPDATE_SSA_TYPE(MAY_BE_REF, ssa_ops[i].op1_def);
+			}
+			break;
 		case ZEND_BIND_GLOBAL:
 			tmp = MAY_BE_REF | MAY_BE_ANY
 				| MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
diff --git a/ext/opcache/tests/bug79193.phpt b/ext/opcache/tests/bug79193.phpt
new file mode 100644
index 0000000000..c500400363
--- /dev/null
+++ b/ext/opcache/tests/bug79193.phpt
@@ -0,0 +1,18 @@
+--TEST--
+Bug #79193: Incorrect type inference for self::$field =& $field
+--FILE--
+<?php
+
+class Test {
+    public static $foo;
+    public static function method($bar) {
+        Test::$foo =& $bar;
+        var_dump(is_int($bar));
+    }
+}
+
+Test::method(1);
+
+?>
+--EXPECT--
+bool(true)
-- 
2.40.0