patch 7.4.1723
Problem:    When using try/catch in 'tabline' it is still considered an
            error and the tabline will be disabled.
Solution:   Check did_emsg instead of called_emsg. (haya14busa, closes #746)
diff --git a/src/screen.c b/src/screen.c
index dc5d175..8044079 100644
--- a/src/screen.c
+++ b/src/screen.c
@@ -10266,16 +10266,16 @@
     /* Use the 'tabline' option if it's set. */
     if (*p_tal != NUL)
     {
-	int	save_called_emsg = called_emsg;
+	int	saved_did_emsg = did_emsg;
 
 	/* Check for an error.  If there is one we would loop in redrawing the
 	 * screen.  Avoid that by making 'tabline' empty. */
-	called_emsg = FALSE;
+	did_emsg = FALSE;
 	win_redr_custom(NULL, FALSE);
-	if (called_emsg)
+	if (did_emsg)
 	    set_string_option_direct((char_u *)"tabline", -1,
 					   (char_u *)"", OPT_FREE, SID_ERROR);
-	called_emsg |= save_called_emsg;
+	did_emsg |= saved_did_emsg;
     }
     else
 #endif