From d398e9959386b5b986551b83c5952a7141ea550d Mon Sep 17 00:00:00 2001
From: Christian Stimming <stimming@tuhh.de>
Date: Sat, 12 Feb 2011 15:53:51 +0000
Subject: [PATCH] Another error message somewhat more verbose.

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@20282 57a11ea4-9604-0410-9ed3-97b8803252fd
---
 src/engine/Query.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/engine/Query.c b/src/engine/Query.c
index 46f9d2cbd6..5c0fa13012 100644
--- a/src/engine/Query.c
+++ b/src/engine/Query.c
@@ -273,6 +273,12 @@ xaccQueryAddAccountGUIDMatch(QofQuery *q, AccountGUIDList *guid_list,
 
     if (!q) return;
 
+    if (!guid_list && how != QOF_GUID_MATCH_NULL)
+    {
+        g_warning("Got a NULL guid_list but the QofGuidMatch is not MATCH_NULL (but instead %d). In other words, the list of GUID matches is empty but it must contain something non-empty.", how);
+        /* qof_query_guid_predicate() would trigger a g_warning as well */
+        return;
+    }
     pred_data = qof_query_guid_predicate (how, guid_list);
     if (!pred_data)
         return;