From 4d3718bab996ec5693bf7a9b0affe18c80f9d273 Mon Sep 17 00:00:00 2001
From: Enno Rehling <enno.rehling@gmail.com>
Date: Sun, 6 May 2018 18:05:35 +0200
Subject: [PATCH] find out why t<=0 assert happens sometimes

---
 src/kernel/calendar.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/kernel/calendar.c b/src/kernel/calendar.c
index df9f6c204..93722b5bc 100644
--- a/src/kernel/calendar.c
+++ b/src/kernel/calendar.c
@@ -4,7 +4,8 @@
 #include "calendar.h"
 #include "move.h" /* storms */
 
-#include <kernel/config.h>
+#include "kernel/config.h"
+#include "util/log.h"
 
 #include <assert.h>
 #include <stdlib.h>
@@ -45,6 +46,10 @@ const gamedate *get_gamedate(int turn_now, gamedate * gd)
     int t = turn_now - first_turn();
 
     assert(gd);
+    if (t<0) {
+        log_fatal("current turn %d is before first %d",
+                turn_now, first_turn());
+    }
     assert(t>=0);
 
     gd->turn = turn_now;