Index: src/http.c
--- src/http.c.orig
+++ src/http.c
@@ -322,7 +322,7 @@ log_duration (char *buf, size_t size, struct timespec 
   struct timespec end, diff;
   clock_gettime (CLOCK_REALTIME, &end);
   diff = timespec_sub (&end, start);
-  snprintf (buf, size, "%ld.%03ld", diff.tv_sec, diff.tv_nsec / 1000000);
+  snprintf (buf, size, "%lld.%03ld", (long long)diff.tv_sec, diff.tv_nsec / 1000000);
   return buf;
 }
 
