Fix usage of casted string in ReflectionParameter ctor

Fixes oss-fuzz #27755.

Author: nikic

ext/reflection/php_reflection.c

@@ -2306,10 +2306,10 @@ ZEND_METHOD(reflection_parameter, __construct)
 					/* nothing to do. don't set is_closure since is the invoke handler,
 					   not the closure itself */
 				} else if ((fptr = zend_hash_find_ptr(&ce->function_table, lcname)) == NULL) {
+					zend_throw_exception_ex(reflection_exception_ptr, 0,
+						"Method %s::%s() does not exist", ZSTR_VAL(ce->name), ZSTR_VAL(name));
 					zend_string_release(name);
 					zend_string_release(lcname);
-					zend_throw_exception_ex(reflection_exception_ptr, 0,
-						"Method %s::%s() does not exist", ZSTR_VAL(ce->name), Z_STRVAL_P(method));
 					return;
 				}
 				zend_string_release(name);

ext/reflection/tests/ReflectionParameter_ctor_cast.phpt

@@ -0,0 +1,18 @@
+--TEST--
+Test method name string cast in ReflectionParameter ctor
+--FILE--
+<?php
+
+class A {}
+try {
+    new ReflectionParameter([
+        A::class,
+        new class { public function __toString() { return 'method'; } }
+    ], 'param');
+} catch (ReflectionException $e) {
+    echo $e->getMessage(), "\n";
+}
+
+?>
+--EXPECT--
+Method A::method() does not exist