https://github.com/canonical/lightdm/pull/261

# Fix LC_IDENTIFICATION undeclared on musl or other libc that doesn't have it defined
# Patch is taken from Alpine linux [1]
# [1]: https://git.alpinelinux.org/aports/tree/community/lightdm/musl-language.patch
# Closes: https://bugs.gentoo.org/766866
diff --git a/liblightdm-gobject/language.c b/liblightdm-gobject/language.c
index 3d4fa96..e38f5ce 100644
--- a/liblightdm-gobject/language.c
+++ b/liblightdm-gobject/language.c
@@ -210,6 +210,7 @@ lightdm_language_get_name (LightDMLanguage *language)

     if (!priv->name)
     {
+#if HAVE_LC_IDENTIFICATION
         g_autofree gchar *locale = get_locale_name (priv->code);
         if (locale)
         {
@@ -223,6 +224,7 @@ lightdm_language_get_name (LightDMLanguage *language)

             setlocale (LC_ALL, current);
         }
+#endif
         if (!priv->name)
         {
             g_auto(GStrv) tokens = g_strsplit_set (priv->code, "_.@", 2);
@@ -250,6 +252,7 @@ lightdm_language_get_territory (LightDMLanguage *language)

     if (!priv->territory && strchr (priv->code, '_'))
     {
+#if HAVE_LC_IDENTIFICATION
         g_autofree gchar *locale = get_locale_name (priv->code);
         if (locale)
         {
@@ -263,6 +266,7 @@ lightdm_language_get_territory (LightDMLanguage *language)

             setlocale (LC_ALL, current);
         }
+#endif
         if (!priv->territory)
         {
             g_auto(GStrv) tokens = g_strsplit_set (priv->code, "_.@", 3);