Merge branch 'PHP-7.4'

* PHP-7.4:
  Fixed bug #79193

Author: nikic

ext/opcache/Optimizer/zend_inference.c

@@ -2957,6 +2957,13 @@ 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;

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)