From dc301231cfd5b34824a8eae2bef192c311177074 Mon Sep 17 00:00:00 2001
From: Ichthyostega <prg@ichthyostega.de>
Date: Sat, 22 Jun 2019 15:15:56 +0200
Subject: [PATCH] Boost-1.65: resolve ambiguity in timevalue comparison

seemingly, the newer boost libraries added an internal type rational<I>::bool_type
together with an overload for the equality comparison operator.

Unfortunately this now renders a comparison ambiguous with the constant zero (i.e. int{0})
because in our use case we employ rational<uint>.

Workaround is to compare explicitly to a zero of the underlying integer type.
---
 src/lib/time/timevalue.hpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/lib/time/timevalue.hpp b/src/lib/time/timevalue.hpp
index a93691ad0..277aa553c 100644
--- a/src/lib/time/timevalue.hpp
+++ b/src/lib/time/timevalue.hpp
@@ -583,7 +583,7 @@ namespace time {
     inline NUM
     __ensure_nonzero (NUM n)
     {
-      if (n == 0)
+      if (n == NUM{0})
         throw error::Logic ("Degenerated frame grid not allowed"
                            , error::LERR_(BOTTOM_VALUE));
       return n;