[evolution] I#2048 - e_rss_preferences_maybe_copy_icon() suggests call of strrchr(NULL, '.')

[Milan Crha <mcrha src gnome org>]

commit f06538db4c5913c53779af6d1294edb9d6cf4cd5
Author: Milan Crha <mcrha redhat com>
Date:   Tue Sep 27 13:58:05 2022 +0200

    I#2048 - e_rss_preferences_maybe_copy_icon() suggests call of strrchr(NULL, '.')
    
    Closes https://gitlab.gnome.org/GNOME/evolution/-/issues/2048

 src/modules/rss/evolution/e-rss-preferences.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/modules/rss/evolution/e-rss-preferences.c b/src/modules/rss/evolution/e-rss-preferences.c
index 8543b0756c..179a483519 100644
--- a/src/modules/rss/evolution/e-rss-preferences.c
+++ b/src/modules/rss/evolution/e-rss-preferences.c
@@ -605,7 +605,7 @@ e_rss_preferences_maybe_copy_icon (const gchar *feed_id,
                return NULL;
        }
 
-       ext = strrchr (basename, '.');
+       ext = basename ? strrchr (basename, '.') : NULL;
        if (!ext || !ext[1])
                ext = ".png";