Fix GH-12208: SimpleXML infinite loop when a cast is used inside a foreach

Closes GH-12229.

Author: nielsdos

NEWS

@@ -15,6 +15,8 @@ PHP                                                                        NEWS
     within foreach). (nielsdos)
   . Fixed bug GH-12223 (Entity reference produces infinite loop in
     var_dump/print_r). (nielsdos)
+  . Fixed bug GH-12208 (SimpleXML infinite loop when a cast is used inside a
+    foreach). (nielsdos)
 
 28 Sep 2023, PHP 8.1.24
 

ext/simplexml/simplexml.c

@@ -1860,7 +1860,7 @@ static int sxe_object_cast_ex(zend_object *readobj, zval *writeobj, int type)
 	sxe = php_sxe_fetch_object(readobj);
 
 	if (type == _IS_BOOL) {
-		node = php_sxe_get_first_node(sxe, NULL);
+		node = php_sxe_get_first_node_non_destructive(sxe, NULL);
 		if (node) {
 			ZVAL_TRUE(writeobj);
 		} else {
@@ -1870,7 +1870,7 @@ static int sxe_object_cast_ex(zend_object *readobj, zval *writeobj, int type)
 	}
 
 	if (sxe->iter.type != SXE_ITER_NONE) {
-		node = php_sxe_get_first_node(sxe, NULL);
+		node = php_sxe_get_first_node_non_destructive(sxe, NULL);
 		if (node) {
 			contents = xmlNodeListGetString((xmlDocPtr) sxe->document->ptr, node->children, 1);
 		}

ext/simplexml/tests/gh12208.phpt

@@ -0,0 +1,26 @@
+--TEST--
+GH-12208 (SimpleXML infinite loop when a cast is used inside a foreach)
+--EXTENSIONS--
+simplexml
+--FILE--
+<?php
+
+$xml = "<root><a>1</a><a>2</a></root>";
+$xml = simplexml_load_string($xml);
+
+$a = $xml->a;
+
+foreach ($a as $test) {
+    var_dump((string) $a->current());
+    var_dump((string) $a);
+    var_dump((bool) $a);
+}
+
+?>
+--EXPECT--
+string(1) "1"
+string(1) "1"
+bool(true)
+string(1) "2"
+string(1) "1"
+bool(true)