Fixed incorrect type inference

Author: dstogov

Zend/Optimizer/zend_inference.c

@@ -3415,7 +3415,9 @@ static zend_always_inline int _zend_update_type_info(
 			UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
 			break;
 		case ZEND_FETCH_THIS:
-			UPDATE_SSA_OBJ_TYPE(op_array->scope, 1, ssa_op->result_def);
+			if (!(op_array->fn_flags & ZEND_ACC_TRAIT_CLONE)) {
+				UPDATE_SSA_OBJ_TYPE(op_array->scope, 1, ssa_op->result_def);
+			}
 			UPDATE_SSA_TYPE(MAY_BE_RCN|MAY_BE_OBJECT, ssa_op->result_def);
 			break;
 		case ZEND_FETCH_OBJ_R:

ext/opcache/tests/jit/gh12482.phpt

@@ -0,0 +1,57 @@
+--TEST--
+GH-12482: Invalid type inference
+--INI--
+opcache.enable=1
+opcache.enable_cli=1
+opcache.jit_hot_func=2
+--FILE--
+<?php
+trait T {
+	function foo() {
+		$cloned = clone $this;
+		$cloned->x = 42;
+		return $cloned;
+	}
+}
+class A {
+	use T;
+	public $a = 1;
+	public $b = 2;
+	public $c = 3;
+	public $x = 4;
+}
+class B {
+	use T;
+	public $x = 5;
+}
+$a = new A;
+var_dump($a->foo());
+var_dump($a->foo());
+$b = new B;
+var_dump($b->foo());
+?>
+--EXPECT--
+object(A)#2 (4) {
+  ["a"]=>
+  int(1)
+  ["b"]=>
+  int(2)
+  ["c"]=>
+  int(3)
+  ["x"]=>
+  int(42)
+}
+object(A)#2 (4) {
+  ["a"]=>
+  int(1)
+  ["b"]=>
+  int(2)
+  ["c"]=>
+  int(3)
+  ["x"]=>
+  int(42)
+}
+object(B)#3 (1) {
+  ["x"]=>
+  int(42)
+}