Merge branch 'PHP-8.3' into PHP-8.4

* PHP-8.3:
  Fix not thread safe RelaxNG invocations in ZTS builds
  Fix not thread safe xmlSchemaParse calls in ZTS builds

NEWS

@@ -21,6 +21,9 @@ PHP                                                                        NEWS
   . Fixed bug GH-20070 (Return type violation in imagefilter when an invalid
     filter is provided). (Girgias)
 
+- LibXML:
+  . Fix not thread safe schema/relaxng calls. (SpencerMalone, nielsdos)
+
 - Opcache:
   . Fixed bug GH-20081 (access to uninitialized vars in preload_load()).
     (Arnaud)

ext/libxml/libxml.c

@@ -40,6 +40,7 @@
 #ifdef LIBXML_SCHEMAS_ENABLED
 #include <libxml/relaxng.h>
 #include <libxml/xmlschemas.h>
+#include <libxml/xmlschemastypes.h>
 #endif
 
 #include "php_libxml.h"
@@ -929,7 +930,14 @@ PHP_LIBXML_API void php_libxml_initialize(void)
 	if (!_php_libxml_initialized) {
 		/* we should be the only one's to ever init!! */
 		ZEND_IGNORE_LEAKS_BEGIN();
+
 		xmlInitParser();
+#ifdef LIBXML_SCHEMAS_ENABLED
+		xmlSchemaInitTypes();
+#endif
+#ifdef LIBXML_RELAXNG_ENABLED
+		xmlRelaxNGInitTypes();
+#endif
 		ZEND_IGNORE_LEAKS_END();
 
 		_php_libxml_default_entity_loader = xmlGetExternalEntityLoader();