simplify code
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 915d30d..cda8135 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -6632,10 +6632,8 @@
 	Py_BEGIN_ALLOW_THREADS
 	res = ftruncate(fd, length);
 	Py_END_ALLOW_THREADS
-	if (res < 0) {
-		posix_error();
-		return NULL;
-	}
+	if (res < 0)
+		return posix_error();
 	Py_INCREF(Py_None);
 	return Py_None;
 }