[gspell] language: add some missing g_return checks

[Sébastien Wilmet <swilmet src gnome org>]

commit e08046a82e85a050cd669d4ba7d1aa93f3300988
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Thu Dec 10 19:27:15 2015 +0100

    language: add some missing g_return checks

 gspell/gspell-language.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)
---
diff --git a/gspell/gspell-language.c b/gspell/gspell-language.c
index dba23f0..524075d 100644
--- a/gspell/gspell-language.c
+++ b/gspell/gspell-language.c
@@ -464,6 +464,8 @@ gspell_language_lookup (const gchar *language_code)
 {
        const GspellLanguage *language = NULL;
 
+       g_return_val_if_fail (language_code != NULL, NULL);
+
        language = spell_language_lookup (language_code);
 
        if (language == NULL)
@@ -500,7 +502,10 @@ gint
 gspell_language_compare (const GspellLanguage *language_a,
                          const GspellLanguage *language_b)
 {
-       return strcmp (language_a->ckey, language_b->ckey);
+       g_return_val_if_fail (language_a != NULL, 0);
+       g_return_val_if_fail (language_b != NULL, 0);
+
+       return g_strcmp0 (language_a->ckey, language_b->ckey);
 }
 
 /**