Make stub file compatible with php 8.4+ parser

ext/compatibility.h

@@ -311,6 +311,11 @@ static inline zend_string *zend_ini_get_value(zend_string *name) {
     }
 }
 
+static inline void zend_string_release_ex(zend_string *str, int persistent) {
+    UNUSED(persistent);
+    zend_string_release(str);
+}
+
 #define ZVAL_DEINDIRECT(z) do { \
         if (Z_TYPE_P(z) == IS_INDIRECT) { \
             (z) = Z_INDIRECT_P(z); \

ext/ddtrace.c

@@ -934,6 +934,7 @@ static zend_object *dd_init_span_data_object(zend_class_entry *class_type, ddtra
     zend_object_std_init(&span->std, class_type);
     span->std.handlers = handlers;
     object_properties_init(&span->std, class_type);
+    ZVAL_NULL(&span->property_parent); // readonly prop cannot be initialized in stub
 #if PHP_VERSION_ID < 80000
     // Not handled in arginfo on these old versions
     array_init(&span->property_meta);
@@ -984,6 +985,7 @@ static zend_object *ddtrace_span_stack_create(zend_class_entry *class_type) {
     stack->root_stack = stack;
     stack->std.handlers = &ddtrace_span_stack_handlers;
     object_properties_init(&stack->std, class_type);
+    ZVAL_NULL(&stack->property_parent); // readonly prop cannot be initialized in stub
     // Explicitly assign property-mapped NULLs
     stack->active = NULL;
     stack->parent_stack = NULL;

ext/ddtrace.stub.php

@@ -205,7 +205,7 @@ class SpanData {
         /**
          * @var SpanData|null The parent span, or 'null' if there is none
          */
-        public readonly SpanData|null $parent = null;
+        public readonly SpanData|null $parent;
 
         /**
          * @var SpanStack The span's stack trace
@@ -321,7 +321,7 @@ class SpanStack {
         /**
          * @var SpanStack|null The parent stack, or 'null' if there is none
          */
-        public readonly SpanStack|null $parent = null;
+        public readonly SpanStack|null $parent;
 
         /**
          * @var SpanData|null The active span