Merge branch 'PHP-8.0' into PHP-8.1

* PHP-8.0:
  Fix #81380 observer may not be initialized properly

Author: krakjoe

NEWS

@@ -5,6 +5,7 @@ PHP                                                                        NEWS
 - Core:
   . Fixed bug #75941 (Fix compile failure on Solaris with clang). (Jaromír
     Doleček)
+  . Fixed bug #81380 (Observer may not be initialized properly). (krakjoe)
 
 30 Sep 2021, PHP 8.1.0RC3
 

Zend/zend_observer.c

@@ -44,11 +44,11 @@ zend_llist zend_observer_fiber_init;
 zend_llist zend_observer_fiber_switch;
 zend_llist zend_observer_fiber_destroy;
 
-int zend_observer_fcall_op_array_extension = -1;
+int zend_observer_fcall_op_array_extension;
 
-ZEND_TLS zend_arena *fcall_handlers_arena = NULL;
-ZEND_TLS zend_execute_data *first_observed_frame = NULL;
-ZEND_TLS zend_execute_data *current_observed_frame = NULL;
+ZEND_TLS zend_arena *fcall_handlers_arena;
+ZEND_TLS zend_execute_data *first_observed_frame;
+ZEND_TLS zend_execute_data *current_observed_frame;
 
 // Call during minit/startup ONLY
 ZEND_API void zend_observer_fcall_register(zend_observer_fcall_init init) {
@@ -78,12 +78,18 @@ ZEND_API void zend_observer_startup(void) {
 	zend_llist_init(&zend_observer_fiber_init, sizeof(zend_observer_fiber_init_handler), NULL, 1);
 	zend_llist_init(&zend_observer_fiber_switch, sizeof(zend_observer_fiber_switch_handler), NULL, 1);
 	zend_llist_init(&zend_observer_fiber_destroy, sizeof(zend_observer_fiber_destroy_handler), NULL, 1);
+
+	zend_observer_fcall_op_array_extension = -1;
 }
 
 ZEND_API void zend_observer_activate(void) {
 	if (ZEND_OBSERVER_ENABLED) {
 		fcall_handlers_arena = zend_arena_create(4096);
+	} else {
+		fcall_handlers_arena = NULL;
 	}
+	first_observed_frame = NULL;
+	current_observed_frame = NULL;
 }
 
 ZEND_API void zend_observer_deactivate(void) {