diff --git a/src/config.cpp b/src/config.cpp
index 78b650c5390e..fbe82097c9cc 100644
--- a/src/config.cpp
+++ b/src/config.cpp
@@ -761,7 +761,6 @@ config& config::add_child(const std::string& key, const config& val)
 	return *v.back();
 }
 
-#ifdef HAVE_CXX11
 config &config::add_child(const std::string &key, config &&val)
 {
 	check_valid(val);
@@ -771,7 +770,6 @@ config &config::add_child(const std::string &key, config &&val)
 	ordered_children.push_back(child_pos(children.find(key), v.size() - 1));
 	return *v.back();
 }
-#endif
 
 config &config::add_child_at(const std::string &key, const config &val, unsigned index)
 {
diff --git a/src/config.hpp b/src/config.hpp
index 2806b1222ac8..113f4b35f80a 100644
--- a/src/config.hpp
+++ b/src/config.hpp
@@ -488,9 +488,7 @@ class config
 	config& add_child(const std::string& key, const config& val);
 	config& add_child_at(const std::string &key, const config &val, unsigned index);
 
-#ifdef HAVE_CXX11
 	config &add_child(const std::string &key, config &&val);
-#endif
 
 	/**
 	 * Returns a reference to the attribute with the given @a key.