From 94ec79079d8cfc12da9670a9b7af7dfdb75e63a0 Mon Sep 17 00:00:00 2001
From: Nathan Phillips <nathan.phillips@diffblue.com>
Date: Thu, 31 Aug 2017 16:46:51 +0100
Subject: [PATCH] Clarified INVARIANT message in get_message_handler

---
 src/util/message.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/util/message.h b/src/util/message.h
index 9da886b0404..758fdd06879 100644
--- a/src/util/message.h
+++ b/src/util/message.h
@@ -137,7 +137,9 @@ class messaget
 
   message_handlert &get_message_handler()
   {
-    INVARIANT(message_handler!=nullptr, "message handler is set");
+    INVARIANT(
+      message_handler!=nullptr,
+      "message handler should be set before calling get_message_handler");
     return *message_handler;
   }