diff --git a/devel/libxsd-frontend/files/patch-libxsd-frontend_types.hxx b/devel/libxsd-frontend/files/patch-libxsd-frontend_types.hxx
new file mode 100644
index 000000000000..6162dbf7fe56
--- /dev/null
+++ b/devel/libxsd-frontend/files/patch-libxsd-frontend_types.hxx
@@ -0,0 +1,62 @@
+--- libxsd-frontend/types.hxx.orig	2022-08-19 06:30:48 UTC
++++ libxsd-frontend/types.hxx
+@@ -13,38 +13,13 @@ namespace XSDFrontend
+ {
+   using std::size_t;
+ 
+-  namespace Bits
+-  {
+-    struct None {};
+-
+-    template <typename C>
+-    struct NarrowerChar
+-    {
+-      typedef None Type;
+-    };
+-
+-    template <>
+-    struct NarrowerChar<wchar_t>
+-    {
+-      typedef char Type;
+-    };
+-  }
+-
+   struct LIBXSD_FRONTEND_SYMEXPORT NonRepresentable: std::exception
+   {
+     virtual char const*
+     what () const throw ();
+   };
+ 
+-  template <typename C, typename NC = typename Bits::NarrowerChar<C>::Type>
+-  class StringTemplate;
+-
+-  template <>
+-  class StringTemplate<Bits::None, Bits::None>
+-  {
+-  };
+-
+-  template <typename C, typename NC>
++  template <typename C, typename NC = char>
+   class StringTemplate : public std::basic_string<C>
+   {
+     typedef std::basic_string<C> Base;
+@@ -114,16 +89,19 @@ namespace XSDFrontend
+ 
+     // Conversion from the Narrower type. Experimental.
+     //
++    template<typename WC = C, typename = std::enable_if_t<std::is_same_v<WC, wchar_t>>>
+     StringTemplate (NC const* s)
+     {
+       from_narrow (s);
+     }
+ 
++    template<typename WC = C, typename = std::enable_if_t<std::is_same_v<WC, wchar_t>>>
+     StringTemplate (StringTemplate<NC> const& other)
+     {
+       from_narrow (other.c_str ());
+     }
+ 
++    template<typename WC = C, typename = std::enable_if_t<std::is_same_v<WC, wchar_t>>>
+     StringTemplate (NarrowerBase const& other)
+     {
+       from_narrow (other.c_str ());