diff --git a/repos/libports/src/lib/libc/kernel.cc b/repos/libports/src/lib/libc/kernel.cc
index dc8d4b9e9b..a5f3e53ee5 100644
--- a/repos/libports/src/lib/libc/kernel.cc
+++ b/repos/libports/src/lib/libc/kernel.cc
@@ -46,11 +46,9 @@ inline void Libc::Main_blockade::wakeup()
 size_t Libc::Kernel::_user_stack_size()
 {
 	size_t size = Component::stack_size();
-	if (!_cloned)
-		return size;
 
 	_libc_env.libc_config().with_sub_node("stack", [&] (Xml_node stack) {
-		size = stack.attribute_value("size", 0UL); });
+		size = stack.attribute_value("size", Number_of_bytes(0)); });
 
 	return size;
 }