Add support for class_alias to preloading

Related to bug #78918.

Author: nikic

ext/opcache/tests/preload_class_alias.inc

@@ -0,0 +1,3 @@
+<?php
+class A {}
+class_alias(A::class, 'B');

ext/opcache/tests/preload_class_alias.phpt

@@ -0,0 +1,17 @@
+--TEST--
+Bug #78918: Class alias during preloading causes assertion failure
+--INI--
+opcache.enable=1
+opcache.enable_cli=1
+opcache.optimization_level=-1
+opcache.preload={PWD}/preload_class_alias.inc
+--SKIPIF--
+<?php require_once('skipif.inc'); ?>
+--FILE--
+<?php
+var_dump(class_exists('A'));
+var_dump(class_exists('B'));
+?>
+--EXPECT--
+bool(true)
+bool(true)

ext/opcache/zend_persist.c

@@ -700,6 +700,12 @@ static void zend_persist_class_entry(zval *zv)
 	zend_class_entry *ce = Z_PTR_P(zv);
 
 	if (ce->type == ZEND_USER_CLASS) {
+		/* The same zend_class_entry may be reused by class_alias */
+		zend_class_entry *new_ce = zend_shared_alloc_get_xlat_entry(ce);
+		if (new_ce) {
+			Z_PTR_P(zv) = new_ce;
+			return;
+		}
 		if ((ce->ce_flags & ZEND_ACC_LINKED)
 		 && (ce->ce_flags & ZEND_ACC_CONSTANTS_UPDATED)
 		 && (ce->ce_flags & ZEND_ACC_PROPERTY_TYPES_RESOLVED)

ext/opcache/zend_persist_calc.c

@@ -352,6 +352,12 @@ static void zend_persist_class_entry_calc(zval *zv)
 	Bucket *p;
 
 	if (ce->type == ZEND_USER_CLASS) {
+		/* The same zend_class_entry may be reused by class_alias */
+		if (zend_shared_alloc_get_xlat_entry(ce)) {
+			return;
+		}
+		zend_shared_alloc_register_xlat_entry(ce, ce);
+
 		check_property_type_resolution(ce);
 
 		ZCG(is_immutable_class) =