diff --git a/zathura/completion.c b/zathura/completion.c
index 002266b..d073a5b 100644
--- a/zathura/completion.c
+++ b/zathura/completion.c
@@ -294,11 +294,11 @@ cc_bookmarks(girara_session_t* session, const char* input)
 
 error_free:
 
-  if (completion) {
+  if (completion != NULL) {
     girara_completion_free(completion);
   }
 
-  if (group) {
+  if (group != NULL) {
     girara_completion_group_free(group);
   }
 
diff --git a/zathura/marks.c b/zathura/marks.c
index 5ec6bf2..5658a07 100644
--- a/zathura/marks.c
+++ b/zathura/marks.c
@@ -160,6 +160,7 @@ cmd_marks_delete(girara_session_t* session, girara_list_t* argument_list)
 
   GIRARA_LIST_FOREACH(argument_list, char*, iter, key_string)
   if (key_string == NULL) {
+    girara_list_iterator_next(iter);
     continue;
   }