Don't hash headers we won't end up using.

Just saving a little work here.

1 files changed, 1 insertions, 1 deletions

diff --git a/message.c b/message.c
index 646403fb..97df4b27 100644
--- a/message.c
+++ b/message.c
@@ -241,7 +241,7 @@ notmuch_message_get_header (notmuch_message_t *message,
     contains = g_hash_table_lookup_extended (message->headers,
 					     header_desired, NULL,
 					     (gpointer *) &value);
-    if (contains)
+    if (contains && value)
 	return value;
 
     if (message->parsing_finished)