Fixed bug #42798 (__autoload() not triggered for classes used in method signature).

NEWS

@@ -32,6 +32,8 @@ PHP                                                                        NEWS
 - Improved and cleaned CGI code. FastCGI is now always enabled and can not be
   disabled. See sapi/cgi/CHANGES for more details. (Dmitry)
 
+- Fixed bug #42798 (__autoload() not triggered for classes used in method
+  signature). (Dmitry)
 - Fixed bug #42657 (ini_get() returns incorrect value when default is NULL).
   (Jani)
 - Fixed bug #42069 (parse_ini_file() allows using some non-alpha numeric

Zend/tests/bug42798.phpt

@@ -0,0 +1,15 @@
+--TEST--
+Bug #42798 (_autoload() not triggered for classes used in method signature)
+--FILE--
+<?php
+function __autoload($className) {
+    print "$className\n";
+    exit();
+}
+
+function foo($c = ok::constant) {
+}
+
+foo();
+--EXPECT--
+ok

Zend/zend_constants.c

@@ -355,8 +355,10 @@ ZEND_API int zend_get_constant_ex(char *name, uint name_len, zval *result, zend_
 			}
 			efree(lcname);
 
-			/* Check for class */
-			ce = zend_fetch_class(class_name, class_name_len, flags TSRMLS_CC);
+			if ((flags & IS_CONSTANT_RT_NS_CHECK) == 0) {
+				/* Check for class */
+				ce = zend_fetch_class(class_name, class_name_len, flags TSRMLS_CC);
+			}
 		}
 
 		if (retval && ce) {

Zend/zend_execute_API.c

@@ -451,6 +451,7 @@ ZEND_API int zend_is_true(zval *op)
 
 #define IS_VISITED_CONSTANT       IS_CONSTANT_INDEX
 #define IS_CONSTANT_VISITED(p)    (Z_TYPE_P(p) & IS_VISITED_CONSTANT)
+#define Z_REAL_TYPE_P(p)          (Z_TYPE_P(p) & ~IS_VISITED_CONSTANT)
 #define MARK_CONSTANT_VISITED(p)  Z_TYPE_P(p) |= IS_VISITED_CONSTANT
 
 ZEND_API int zval_update_constant_ex(zval **pp, void *arg, zend_class_entry *scope TSRMLS_DC)
@@ -474,7 +475,7 @@ ZEND_API int zval_update_constant_ex(zval **pp, void *arg, zend_class_entry *sco
 		refcount = p->refcount;
 		is_ref = p->is_ref;
 
-		if (!zend_get_constant_ex(p->value.str.val, p->value.str.len, &const_value, scope, Z_TYPE_P(p) TSRMLS_CC)) {
+		if (!zend_get_constant_ex(p->value.str.val, p->value.str.len, &const_value, scope, Z_REAL_TYPE_P(p) TSRMLS_CC)) {
 			if ((colon = memchr(Z_STRVAL_P(p), ':', Z_STRLEN_P(p))) && colon[1] == ':') {
 				zend_error(E_ERROR, "Undefined class constant '%s'", Z_STRVAL_P(p));
 			}