Fixed regression introduced by php#9601

Author: dstogov

ext/ffi/ffi.c

@@ -4290,7 +4290,8 @@ ZEND_METHOD(FFI, addr) /* {{{ */
 	cdata = (zend_ffi_cdata*)Z_OBJ_P(zv);
 	type = ZEND_FFI_TYPE(cdata->type);
 
-	if (GC_REFCOUNT(&cdata->std) == 1 && Z_REFCOUNT_P(arg) == 1 && type->kind == ZEND_FFI_TYPE_POINTER) {
+	if (GC_REFCOUNT(&cdata->std) == 1 && Z_REFCOUNT_P(arg) == 1 && type->kind == ZEND_FFI_TYPE_POINTER
+	 && cdata->ptr == &cdata->ptr_holder) {
 		zend_throw_error(zend_ffi_exception_ce, "FFI::addr() cannot create a reference to a temporary pointer");
 		RETURN_THROWS();
 	}

ext/ffi/tests/addr_in_lval.phpt

@@ -0,0 +1,31 @@
+--TEST--
+Assignment to CDATA though FFI::addr() trick
+--EXTENSIONS--
+ffi
+--INI--
+ffi.enable=1
+--FILE--
+<?php
+$f = FFI::cdef("typedef struct { char *bar; } other;");
+class Container {
+    public $data;
+    function __construct($f) { $this->data = $f->new("other"); }
+    function &getBar() { return $this->data->bar; } // return by ref to get CData instead of null
+}
+$container = new Container($f);
+$data = $f->new("char[2]");
+$data[0] = "1";
+FFI::addr($container->getBar())[0] = $f->cast("char*", $data); // directly write it
+var_dump($container);
+?>
+--EXPECT--
+object(Container)#2 (1) {
+  ["data"]=>
+  object(FFI\CData:struct <anonymous>)#3 (1) {
+    ["bar"]=>
+    object(FFI\CData:char*)#6 (1) {
+      [0]=>
+      string(1) "1"
+    }
+  }
+}